WorldWideScience

Sample records for controls regulatory tolerance

  1. Regulatory focus affects physician risk tolerance.

    Science.gov (United States)

    Veazie, Peter J; McIntosh, Scott; Chapman, Benjamin P; Dolan, James G

    2014-01-01

    Risk tolerance is a source of variation in physician decision-making. This variation, if independent of clinical concerns, can result in mistaken utilization of health services. To address such problems, it will be helpful to identify nonclinical factors of risk tolerance, particularly those amendable to intervention-regulatory focus theory suggests such a factor. This study tested whether regulatory focus affects risk tolerance among primary care physicians. Twenty-seven primary care physicians were assigned to promotion-focused or prevention-focused manipulations and compared on the Risk Taking Attitudes in Medical Decision Making scale using a randomization test. Results provide evidence that physicians assigned to the promotion-focus manipulation adopted an attitude of greater risk tolerance than the physicians assigned to the prevention-focused manipulation (p = 0.01). The Cohen's d statistic was conventionally large at 0.92. Results imply that situational regulatory focus in primary care physicians affects risk tolerance and may thereby be a nonclinical source of practice variation. Results also provide marginal evidence that chronic regulatory focus is associated with risk tolerance (p = 0.05), but the mechanism remains unclear. Research and intervention targeting physician risk tolerance may benefit by considering situational regulatory focus as an explanatory factor.

  2. Fault Tolerant Feedback Control

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2001-01-01

    An architecture for fault tolerant feedback controllers based on the Youla parameterization is suggested. It is shown that the Youla parameterization will give a residual vector directly in connection with the fault diagnosis part of the fault tolerant feedback controller. It turns out...... that there is a separation be-tween the feedback controller and the fault tolerant part. The closed loop feedback properties are handled by the nominal feedback controller and the fault tolerant part is handled by the design of the Youla parameter. The design of the fault tolerant part will not affect the design...... of the nominal feedback con-troller....

  3. Fault Tolerant Control Systems

    DEFF Research Database (Denmark)

    Bøgh, S. A.

    This thesis considered the development of fault tolerant control systems. The focus was on the category of automated processes that do not necessarily comprise a high number of identical sensors and actuators to maintain safe operation, but still have a potential for improving immunity to component...

  4. What is Fault Tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Frei, C. W.; Kraus, K.

    2000-01-01

    Faults in automated processes will often cause undesired reactions and shut-down of a controlled plant, and the consequences could be damage to the plant, to personnel or the environment. Fault-tolerant control is the synonym for a set of recent techniques that were developed to increase plant...... availability and reduce the risk of safety hazards. Its aim is to prevent that simple faults develop into serious failure. Fault-tolerant control merges several disciplines to achieve this goal, including on-line fault diagnosis, automatic condition assessment and calculation of remedial actions when a fault...... is detected. The envelope of the possible remedial actions is wide. This paper introduces tools to analyze and explore structure and other fundamental properties of an automated system such that any redundancy in the process can be fully utilized to enhance safety and a availability....

  5. Fault Tolerant Wind Farm Control

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2013-01-01

    In the recent years the wind turbine industry has focused on optimizing the cost of energy. One of the important factors in this is to increase reliability of the wind turbines. Advanced fault detection, isolation and accommodation are important tools in this process. Clearly most faults are deal...... scenarios. This benchmark model is used in an international competition dealing with Wind Farm fault detection and isolation and fault tolerant control....

  6. Radiation practices and regulatory control

    International Nuclear Information System (INIS)

    1997-01-01

    The general principles to be observed in the regulatory control of ionizing radiation use and practices are specified in the guide. It also takes into account of additions and alterations needed for for compliance with the European Union (EU) directives that have not been mentioned in other STUK/ST-guides. (6 refs.)

  7. Radiation practices and regulatory control

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    The general principles to be observed in the regulatory control of ionizing radiation use and practices are specified in the guide. It also takes into account of additions and alterations needed for for compliance with the European Union (EU) directives that have not been mentioned in other STUK/ST-guides. (6 refs.).

  8. The plant cytoskeleton controls regulatory volume increase.

    Science.gov (United States)

    Liu, Qiong; Qiao, Fei; Ismail, Ahmed; Chang, Xiaoli; Nick, Peter

    2013-09-01

    The ability to adjust cell volume is required for the adaptation to osmotic stress. Plant protoplasts can swell within seconds in response to hypoosmotic shock suggesting that membrane material is released from internal stores. Since the stability of plant membranes depends on submembraneous actin, we asked, whether this regulatory volume control depends on the cytoskeleton. As system we used two cell lines from grapevine which differ in their osmotic tolerance and observed that the cytoskeleton responded differently in these two cell lines. To quantify the ability for regulatory volume control, we used hydraulic conductivity (Lp) as readout and demonstrated a role of the cytoskeleton in protoplast swelling. Chelation of calcium, inhibition of calcium channels, or manipulation of membrane fluidity, did not significantly alter Lp, whereas direct manipulation of the cytoskeleton via specific chemical reagents, or indirectly, through the bacterial elicitor Harpin or activation of phospholipase D, was effective. By optochemical engineering of actin using a caged form of the phytohormone auxin we can break the symmetry of actin organisation resulting in a localised deformation of cell shape indicative of a locally increased Lp. We interpret our findings in terms of a model, where the submembraneous cytoskeleton controls the release of intracellular membrane stores during regulatory volume change. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Accident-tolerant control rod

    International Nuclear Information System (INIS)

    Ohta, Hirokazu; Sawabe, Takashi; Ogata, Takanari

    2013-01-01

    Boron carbide (B 4 C) and hafnium (Hf) metal are used for the neutron absorber materials of control rods in BWRs, and silver-indium-cadmium (Ag-In-Cd) alloy is used in PWRs. These materials are clad with stainless steel. The eutectic point of B 4 C and iron (Fe) is about 1150 deg. C and the melting point of Ag-In-Cd alloy is about 800 deg. C, which are lower than the temperature of zircaloy - steam reaction increases rapidly (∼1200 deg. C). Accordingly, it is possible that the control rods melt and collapse before the reactor core is significantly damaged in the case of severe accidents. Since the neutron absorber would be separated from the fuels, there is a risk of re-criticality, when pure water or seawater is injected for emergency cooling. In order to ensure sub-criticality and extend options of emergency cooling in the course of severe accidents, a concept of accident-tolerant control rod (ACT) has been derived. ACT utilises a new absorber material having the following properties: - higher neutron absorption than current control rod; - higher melting or eutectic temperature than 1200 deg. C where rapid zircaloy oxidation occurs; - high miscibility with molten fuel materials. The candidate of a new absorber material for ATC includes gadolinia (Gd 2 O 3 ), samaria (Sm 2 O 3 ), europia (Eu 2 O 3 ), dysprosia (Dy 2 O 3 ), hafnia (HfO 2 ). The melting point of these materials and the liquefaction temperature with Fe are higher than the rapid zircaloy oxidation temperature. ACT will not collapse before the core melt-down. After the core melt-down, the absorber material will be mixed with molten fuel material. The current absorber materials, such as B 4 C, Hf and Ag-In-Cd, are charged at the tip of ATC in which the neutron flux is high, and a new absorber material is charged in the low-flux region. This design could minimise the degradation of a new absorber material by the neutron absorption and the influence of ATC deployment on reactor control procedure. As a

  10. Regulatory control of fuel design and manufacturing

    International Nuclear Information System (INIS)

    1994-01-01

    The regulatory control of the design and manufacturing of the nuclear fuel and of the control rods aims to ensure conformance to set requirements during normal operating conditions, anticipated operational transients and postulated accident conditions. The regulatory control of design, manufacturing, receiving inspections and the start of operation of the nuclear fuel are specified in the guide. The regulatory control procedure also applies to the control rods and the shield elements

  11. Fault tolerant control design for hybrid systems

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hao; Jiang, Bin [Nanjing University of Aeronautics and Astronautics, Nanjing (China); Cocquempot, Vincent [Universite des Sciences et Technologies de Lille, Villeneuve d' Ascq (France)

    2010-07-01

    This book intends to provide the readers a good understanding on how to achieve Fault Tolerant Control goal of Hybrid Systems. The book can be used as a reference for the academic research on Fault Tolerant Control and Hybrid Systems or used in Ph.D. study of control theory and engineering. The knowledge background for this monograph would be some undergraduate and graduate courses on Fault Diagnosis and Fault Tolerant Control theory, linear system theory, nonlinear system theory, Hybrid Systems theory and Discrete Event System theory. (orig.)

  12. Regulatory Control of Radiation Sources. Safety Guide

    International Nuclear Information System (INIS)

    2009-01-01

    This Safety Guide is intended to assist States in implementing the requirements established in Safety Standards Series No. GS-R-1, Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety, for a national regulatory infrastructure to regulate any practice involving radiation sources in medicine, industry, research, agriculture and education. The Safety Guide provides advice on the legislative basis for establishing regulatory bodies, including the effective independence of the regulatory body. It also provides guidance on implementing the functions and activities of regulatory bodies: the development of regulations and guides on radiation safety; implementation of a system for notification and authorization; carrying out regulatory inspections; taking necessary enforcement actions; and investigating accidents and circumstances potentially giving rise to accidents. The various aspects relating to the regulatory control of consumer products are explained, including justification, optimization of exposure, safety assessment and authorization. Guidance is also provided on the organization and staffing of regulatory bodies. Contents: 1. Introduction; 2. Legal framework for a regulatory infrastructure; 3. Principal functions and activities of the regulatory body; 4. Regulatory control of the supply of consumer products; 5. Functions of the regulatory body shared with other governmental agencies; 6. Organization and staffing of the regulatory body; 7. Documentation of the functions and activities of the regulatory body; 8. Support services; 9. Quality management for the regulatory system.

  13. Diagnosis and fault-tolerant control

    CERN Document Server

    Blanke, Mogens; Lunze, Jan; Staroswiecki, Marcel

    2016-01-01

    Fault-tolerant control aims at a gradual shutdown response in automated systems when faults occur. It satisfies the industrial demand for enhanced availability and safety, in contrast to traditional reactions to faults, which bring about sudden shutdowns and loss of availability. The book presents effective model-based analysis and design methods for fault diagnosis and fault-tolerant control. Architectural and structural models are used to analyse the propagation of the fault through the process, to test the fault detectability and to find the redundancies in the process that can be used to ensure fault tolerance. It also introduces design methods suitable for diagnostic systems and fault-tolerant controllers for continuous processes that are described by analytical models of discrete-event systems represented by automata. The book is suitable for engineering students, engineers in industry and researchers who wish to get an overview of the variety of approaches to process diagnosis and fault-tolerant contro...

  14. An architecture for fault tolerant controllers

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob

    2005-01-01

    degradation in the sense of guaranteed degraded performance. A number of fault diagnosis problems, fault tolerant control problems, and feedback control with fault rejection problems are formulated/considered, mainly from a fault modeling point of view. The method is illustrated on a servo example including......A general architecture for fault tolerant control is proposed. The architecture is based on the (primary) YJBK parameterization of all stabilizing compensators and uses the dual YJBK parameterization to quantify the performance of the fault tolerant system. The approach suggested can be applied...

  15. Control switching in high performance and fault tolerant control

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2010-01-01

    The problem of reliability in high performance control and in fault tolerant control is considered in this paper. A feedback controller architecture for high performance and fault tolerance is considered. The architecture is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization. By usi...

  16. Fault tolerancy in cooperative adaptive cruise control

    NARCIS (Netherlands)

    Nunen, E. van; Ploeg, J.; Medina, A.M.; Nijmeijer, H.

    2013-01-01

    Future mobility requires sound solutions in the field of fault tolerance in real-time applications amongst which Cooperative Adaptive Cruise Control (CACC). This control system cannot rely on the driver as a backup and is constantly active and therefore more prominent to the occurrences of faults

  17. Transitional-2 B cells acquire regulatory function during tolerance induction and contribute to allograft survival.

    Science.gov (United States)

    Moreau, Aurélie; Blair, Paul A; Chai, Jian-Guo; Ratnasothy, Kulachelvy; Stolarczyk, Emilie; Alhabbab, Rowa; Rackham, Chloe L; Jones, Peter M; Smyth, Lesley; Elgueta, Raul; Howard, Jane K; Lechler, Robert I; Lombardi, Giovanna

    2015-03-01

    In humans, tolerance to renal transplants has been associated with alterations in B-cell gene transcription and maintenance of the numbers of circulating transitional B cells. Here, we use a mouse model of transplantation tolerance to investigate the contribution of B cells to allograft survival. We demonstrate that transfer of B cells from mice rendered tolerant to MHC class I mismatched skin grafts can prolong graft survival in a dose-dependent and antigen-specific manner to a degree similar to that afforded by graft-specific regulatory T (Treg) cells. Tolerance in this model was associated with an increase in transitional-2 (T2) B cells. Only T2 B cells from tolerized mice, not naïve T2 nor alloantigen experienced T2, were capable of prolonging skin allograft survival, and suppressing T-cell activation. Tolerized T2 B cells expressed lower levels of CD86, increased TIM-1, and demonstrated a preferential survival in vivo. Furthermore, we demonstrate a synergistic effect between tolerized B cells and graft-specific Treg cells. IL-10 production by T2 B cells did not contribute to tolerance, as shown by transfer of B cells from IL-10(-/-) mice. These results suggest that T2 B cells in tolerant patients may include a population of regulatory B cells that directly inhibit graft rejection. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Radiation tolerant power converter controls

    CERN Document Server

    Todd, B; King, Q; Uznanski, S

    2012-01-01

    The Large Hadron Collider (LHC) at the European Organisation for Nuclear Research (CERN) is the world's most powerful particle collider. The LHC has several thousand magnets, both warm and super-conducting, which are supplied with current by power converters. Each converter is controlled by a purpose-built electronic module called a Function Generator Controller (FGC). The FGC allows remote control of the power converter and forms the central part of a closed-loop control system where the power converter voltage is set, based on the converter output current and magnet-circuit characteristics. Some power converters and FGCs are located in areas which are exposed to beam-induced radiation. There are numerous radiation induced effects, some of which lead to a loss of control of the power converter, having a direct impact upon the accelerator's availability. Following the first long shut down (LS1), the LHC will be able to run with higher intensity beams and higher beam energy. This is expected to lead to signifi...

  19. Fault tolerant control of systems with saturations

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2013-01-01

    This paper presents framework for fault tolerant controllers (FTC) that includes input saturation. The controller architecture known from FTC is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization is extended to handle input saturation. Applying this controller architecture in connec......This paper presents framework for fault tolerant controllers (FTC) that includes input saturation. The controller architecture known from FTC is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization is extended to handle input saturation. Applying this controller architecture...... in connection with faulty systems including input saturation gives an additional YJBK transfer function related to the input saturation. In the fault free case, this additional YJBK transfer function can be applied directly for optimizing the feedback loop around the input saturation. In the faulty case......, the design problem is a mixed design problem involved both parametric faults and input saturation....

  20. Regulatory control of nuclear power plants

    International Nuclear Information System (INIS)

    2002-01-01

    The purpose of this book is to support IAEA training courses and workshops in the field of regulatory control of nuclear power plants as well as to support the regulatory bodies of Member States in their own training activities. The target group is the professional staff members of nuclear safety regulatory bodies supervising nuclear power plants and having duties and responsibilities in the following regulatory fields: regulatory framework; regulatory organization; regulatory guidance; licensing and licensing documents; assessment of safety; and regulatory inspection and enforcement. Important topics such as regulatory competence and quality of regulatory work as well as emergency preparedness and public communication are also covered. The book also presents the key issues of nuclear safety such as 'defence-in-depth' and safety culture and explains how these should be taken into account in regulatory work, e.g. during safety assessment and regulatory inspection. The book also reflects how nuclear safety has been developed during the years on the basis of operating experience feedback and results of safety research by giving topical examples. The examples cover development of operating procedures and accident management to cope with complicated incidents and severe accidents to stress the importance of regulatory role in nuclear safety research. The main target group is new staff members of regulatory bodies, but the book also offers good examples for more experienced inspectors to be used as comparison and discussion basis in internal workshops organized by the regulatory bodies for refreshing and continuing training. The book was originally compiled on the basis of presentations provided during the two regulatory control training courses in 1997 and 1998. The textbook was reviewed at the beginning of the years 2000 and 2002 by IAEA staff members and consistency with the latest revisions of safety standards have been ensured. The textbook was completed in the

  1. Regulatory control, legislation and framework

    International Nuclear Information System (INIS)

    Parthasarathy, K.S.

    1998-01-01

    The legislation and regulations, a regulatory authority to authorise and inspect the regulated activities and to enforce the legislation and regulations, sufficient financial and man-power resources are the essential parts of a national infrastructure to implement the Basic Safety Standards. The legal framework consists of legislation (Act passed by Parliament) and the regulations (framed by the government and endorsed by the Parliament). This paper is primarily deals with the the legal framework set up in India for atomic energy activities

  2. Furfural and hydroxymethylfurfural tolerance in Escherichia coli ΔacrR regulatory mutants.

    Science.gov (United States)

    Luhe, Annette Lin; Lim, Chan Yuen; Gerken, Henri; Wu, Jinchuan; Zhao, Hua

    2015-01-01

    The presence of the highly toxic furfural and hydroxymethylfurfural (HMF) in the hydrolysate of lignocellulosic biomass prompted the investigation of the Escherichia coli ΔacrR regulatory mutant for higher tolerance to these compounds, to facilitate the production of biofuels and biochemicals, and further biocatalytic conversions. In comparison with the parental strain, the regulatory mutant with the upregulated efflux pump AcrAB-TolC produced moderately better growth and higher tolerance to concentrations of furfural and HMF between 1 and 2 g L(-1) . © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  3. Hematopoietic chimerism and transplantation tolerance: a role for regulatory T cells

    Directory of Open Access Journals (Sweden)

    Lise ePasquet

    2011-12-01

    Full Text Available The major obstacle in transplantation medicine is rejection of donor tissues by the host’s immune system. Immunosuppressive drugs can delay but not prevent loss of transplants, and their efficiency is strongly impacted by inter-individual pharmacokinetic differences. Moreover, due to the global immunosuppression induced and to the broad distribution of their targets amongst human tissues, these drugs have severe side effects. Induction of donor-specific non-responsiveness (i.e. immunological tolerance to transplants would solve these problems and would substantially ameliorate patients’ quality of life. It is widely believed that bone marrow or hematopoietic stem cell transplantation, and resulting (mixed hematopoietic chimerism, invariably leads to immunological tolerance to organs of the same donor. A careful analysis of the literature, reviewed here, indeed shows that chimerism consistently prolongs allograft survival. However, in absence of additional conditioning leading to the development of active regulatory mechanisms, it does not prevent chronic rejection. A central role for active tolerance in transplantation-tolerance is also supported by recent data showing that genuine immunological tolerance to organ allografts can be achieved by combining induction of hematopoietic chimerism with infusion of regulatory T lymphocytes. Therefore, conditioning regimens that lead to the establishment of hematopoietic chimerism plus active regulatory mechanisms appear required for induction of genuine tolerance to allogeneic grafts.

  4. 21 CFR 109.4 - Establishment of tolerances, regulatory limits, and action levels.

    Science.gov (United States)

    2010-04-01

    ... a food additive, may be established to define a level of contamination at which a food may be... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Establishment of tolerances, regulatory limits, and action levels. 109.4 Section 109.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

  5. 21 CFR 509.4 - Establishment of tolerances, regulatory limits, and action levels.

    Science.gov (United States)

    2010-04-01

    ... a food additive, may be established to define a level of contamination at which a food may be... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Establishment of tolerances, regulatory limits, and action levels. 509.4 Section 509.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

  6. Regulatory T-cells and immune tolerance in pregnancy : a new target for infertility treatment?

    NARCIS (Netherlands)

    Guerin, Leigh R.; Prins, Jelmer R.; Robertson, Sarah A.

    2009-01-01

    Adaptation of the maternal immune response to accommodate the semi-allogeneic fetus is necessary for pregnancy success, and disturbances in maternal tolerance are implicated in infertility and reproductive pathologies. T regulatory (Treg) cells are a recently discovered subset of T-lymphocytes with

  7. A Concept for fault tolerant controllers

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2009-01-01

    This paper describe a concept for fault tolerant controllers (FTC) based on the YJBK (after Youla, Jabr, Bongiorno and Kucera) parameterization. This controller architecture will allow to change the controller on-line in the case of faults in the system. In the described FTC concept, a safe mode...... controller is applied as the basic feedback controller. A controller for normal operation with high performance is obtained by including certain YJBK parameters (transfer functions) in the controller. This will allow a fast switch from normal operation to safe mode operation in case of critical faults...... in the system. The described FTC architecture allow the different feedback controllers to apply different sets of sensors and actuators....

  8. Fault Tolerant Control Using Gaussian Processes and Model Predictive Control

    Directory of Open Access Journals (Sweden)

    Yang Xiaoke

    2015-03-01

    Full Text Available Essential ingredients for fault-tolerant control are the ability to represent system behaviour following the occurrence of a fault, and the ability to exploit this representation for deciding control actions. Gaussian processes seem to be very promising candidates for the first of these, and model predictive control has a proven capability for the second. We therefore propose to use the two together to obtain fault-tolerant control functionality. Our proposal is illustrated by several reasonably realistic examples drawn from flight control.

  9. Regulatory control of radiation sources in Slovakia

    International Nuclear Information System (INIS)

    Auxtova, L.

    2001-01-01

    In Slovakia, there are two regulatory authorities. Regulatory control of the utilization of nuclear energy, based on the Slovak National Council's law No. 130/1998 on the peaceful uses of nuclear energy, is exercised by the Nuclear Regulatory Authority of the Slovak Republic. The second regulatory authority - the Ministry of Health - is empowered by law No. 72/1994 on the protection of human health to license radiation sources and is responsible for radiation protection supervision (there are nearly 3000 establishments with sealed sources, radiation generators and unsealed sources in Slovakia). Pursuant to a new radiation protection regulation based on international standards, radiation sources are to be categorized in six classes according to the associated exposure and contamination hazards. A national strategy for improving the safety of radiation sources over their life-cycle and for the management of disused and orphan sources is being prepared for governmental approval. (author)

  10. Regulatory Control of Radioactive Sources in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, M.; Martin, J.L., E-mail: mrm@csn.es [Nuclear Safety Council, Madrid (Spain)

    2011-07-15

    The arrangements for the regulatory control of the safety and security of sealed radioactive sources in Spain are described. Emphasis is given to the situations which are most likely to result in the loss of control of sources and on the procedures introduced to reduce the likelihood of losses in these cases. Finally, the strategy for locating sources which have been lost from control (orphan sources) is described. (author)

  11. Regulatory BC1 RNA in Cognitive Control

    Science.gov (United States)

    Iacoangeli, Anna; Dosunmu, Aderemi; Eom, Taesun; Stefanov, Dimitre G.; Tiedge, Henri

    2017-01-01

    Dendritic regulatory BC1 RNA is a non-protein-coding (npc) RNA that operates in the translational control of gene expression. The absence of BC1 RNA in BC1 knockout (KO) animals causes translational dysregulation that entails neuronal phenotypic alterations including prolonged epileptiform discharges, audiogenic seizure activity in vivo, and…

  12. Adaptive Control Allocation for Fault Tolerant Overactuated Autonomous Vehicles

    Science.gov (United States)

    2007-11-01

    Tolerant Overactuated Autonomous Vehicles Casavola, A.; Garone, E. (2007) Adaptive Control Allocation for Fault Tolerant Overactuated Autonomous ...Adaptive Control Allocation for Fault Tolerant Overactuated Autonomous Vehicles 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...Tolerant Overactuated Autonomous Vehicles 3.2 - 2 RTO-MP-AVT-145 UNCLASSIFIED/UNLIMITED Control allocation problem (CAP) - Given a virtual input v(t

  13. Diagnosis and Fault-tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Kinnaert, Michel; Lunze, Jan

    the applicability of the presented methods. The theoretical results are illustrated by two running examples which are used throughout the book. The book addresses engineering students, engineers in industry and researchers who wish to get a survey over the variety of approaches to process diagnosis and fault......The book presents effective model-based analysis and design methods for fault diagnosis and fault-tolerant control. Architectural and structural models are used to analyse the propagation of the fault through the process, to test the fault detectability and to find the redundancies in the process...

  14. Regulatory aspects of criticality control in Australia

    International Nuclear Information System (INIS)

    Zimin, Sergei

    2003-01-01

    With the creation of Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) the Australian approach to criticality safety was revisited. Consistency with international best practices is required by the Act that created ARPANSA and this was applied to practices in criticality safety adopted in other countries. This required extensive regulatory efforts both in auditing the major Australian Nuclear Operator, Australian Nuclear Science and Technology Organisation (ANSTO), and assessing the existing in Australia criticality safety practices and implementing the required changes using the new legislative power of ARPANSA. The adopted regulatory approach is formulated through both the issued by ARPANSA licenses for nuclear installations (including reactors, fuel stores and radioactive waste stores) and the string of new regulatory documents, including the Regulatory Assessment Principles and the Regulatory Assessment Guidelines for criticality safety. The main features of the adopted regulation include the requirements of independent peer-review, ongoing refresher training coupled with annual accreditation and the reliance on the safe design rather than on an administrative control. (author)

  15. Regulatory control of radiation sources in Germany

    International Nuclear Information System (INIS)

    Coy, K.

    1998-01-01

    The regulatory programme governing the safe use of radioisotopes in Germany is based on the federal legislation enacted as Atomic Energy Control Act (Atomgesetz) and Radiation Protection Ordinance (Strahlen-schutzverordnung) and its implementation by the competent authorities of the individual states. Despite this highly decentralized infrastructure of enforcement the basic principles of regulations described in this paper such as authorization criteria, conditions imposed as well as depth and intensity of inspection balanced according to the individual radiation hazard involved are harmonized to the greatest possible extent by regular coordination among the competent authorities as well as a series of technical regulations such as standards and guidelines. (author)

  16. Naturally occurring tolerance acquisition to foods in previously allergic children is characterized by antigen specificity and associated with increased subsets of regulatory T cells.

    Science.gov (United States)

    Qamar, N; Fishbein, A B; Erickson, K A; Cai, M; Szychlinski, C; Bryce, P J; Schleimer, R P; Fuleihan, R L; Singh, A M

    2015-11-01

    Food allergy affects approximately 6-8% of children, and increasing in prevalence. Some children naturally outgrow their food allergy without intervention, but the mechanisms by which this occurs remain poorly understood. We sought to investigate the role of regulatory T cells in the development of naturally acquired tolerance. Fifty-eight children (1-18 years) with either egg or peanut allergy, recent acquisition of natural tolerance to egg or peanut, or no food allergy were studied. Peripheral blood mononuclear cells (PBMC) from these groups were stimulated with relevant antigen for 48 h and flow cytometry performed to characterize both surface (CD3, CD4, CD25, CD14, CD19, and CD127) and intracellular markers (IL-10, Foxp3, and IL-5). Resting PBMC from naturally tolerant patients had significantly increased CD3+CD4+CD25+CD127loFoxp3+ cells, when compared to allergic or control patients (mean 6.36 vs. 2.37 vs. 2.62%, respectively, P naturally tolerant patients also had increased IL-10-expressing CD25+CD127lo cells (6.33 vs. 1.65 vs. 0.7, P naturally tolerant patients suggests an important role for regulatory T cell subsets in the acquisition of natural tolerance. © 2015 John Wiley & Sons Ltd.

  17. Recent advances in the dissection of drought-stress regulatory networks and strategies for development of drought-tolerant transgenic rice plants.

    Science.gov (United States)

    Todaka, Daisuke; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2015-01-01

    Advances have been made in the development of drought-tolerant transgenic plants, including cereals. Rice, one of the most important cereals, is considered to be a critical target for improving drought tolerance, as present-day rice cultivation requires large quantities of water and as drought-tolerant rice plants should be able to grow in small amounts of water. Numerous transgenic rice plants showing enhanced drought tolerance have been developed to date. Such genetically engineered plants have generally been developed using genes encoding proteins that control drought regulatory networks. These proteins include transcription factors, protein kinases, receptor-like kinases, enzymes related to osmoprotectant or plant hormone synthesis, and other regulatory or functional proteins. Of the drought-tolerant transgenic rice plants described in this review, approximately one-third show decreased plant height under non-stressed conditions or in response to abscisic acid treatment. In cereal crops, plant height is a very important agronomic trait directly affecting yield, although the improvement of lodging resistance should also be taken into consideration. Understanding the regulatory mechanisms of plant growth reduction under drought stress conditions holds promise for developing transgenic plants that produce high yields under drought stress conditions. Plant growth rates are reduced more rapidly than photosynthetic activity under drought conditions, implying that plants actively reduce growth in response to drought stress. In this review, we summarize studies on molecular regulatory networks involved in response to drought stress. In a separate section, we highlight progress in the development of transgenic drought-tolerant rice plants, with special attention paid to field trial investigations.

  18. Pavlovian control of cross-tolerance between pentobarbital and ethanol.

    Science.gov (United States)

    Cappell, H; Roach, C; Poulos, C X

    1981-01-01

    Tolerance to several effects of a number of drugs has been shown to depend on Pavlovian conditioning processes. Experiment I extended the compensatory conditioning model (Siegel 1975) to tolerance to the hypothermic effect of pentobarbital (30 mg/kg). In Experiment I, rats that acquired hypothermic tolerance in one environment did not display tolerance when tested in an environment not previously associated with drug administration. In Experiment II, rats were made tolerant to the hypothermic effect of pentobarbital (30 mg/kg) and tested for cross-tolerance to ethanol (2.5 g/kg). Cross-tolerance was observed, but it was significantly reduced if the test was in an environment different from the one in which tolerance to pentobarbital was originally acquired. Thus, the compensatory conditioning model accounts for at least part of the tolerance and cross-tolerance to the thermic effects of alcohol and pentobarbital. The physiological processes in the CNS underlying tolerance and cross-tolerance for these drugs, therefore, are controlled by associative processes.

  19. Fault Tolerant Control: A Simultaneous Stabilization Result

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Blondel, V.D.

    2004-01-01

    This paper discusses the problem of designing fault tolerant compensators that stabilize a given system both in the nominal situation, as well as in the situation where one of the sensors or one of the actuators has failed. It is shown that such compensators always exist, provided that the system...... is detectable from each output and that it is stabilizable. The proof of this result is constructive, and a worked example shows how to design a fault tolerant compensator for a simple, yet challeging system. A family of second order systems is described that requires fault tolerant compensators of arbitrarily...

  20. Regulatory T cells: serious contenders in the promise for immunological tolerance in transplantation

    Directory of Open Access Journals (Sweden)

    Niloufar eSafinia

    2015-08-01

    Full Text Available Regulatory T cells (Tregs play an important role in immunoregulation and have been shown in animal models to promote transplantation tolerance and curb autoimmunity following their adoptive transfer. The safety and potential therapeutic efficacy of these cells has already been reported in Phase I trials of bone marrow transplantation and type I diabetes, the success of which has motivated the broadened application of these cells in solid organ transplantation. Despite major advances in the clinical translation of these cells, there are still key questions to be addressed to ensure that Tregs attest their reputation as ideal candidates for tolerance induction. In this review, we will discuss the unique traits of Tregs that have attracted such fame in the arena of tolerance induction. We will outline the protocols used for their ex vivo expansion and discuss the future directions of Treg cell therapy. In this regard, we will review the concept of Treg heterogeneity, the desire to isolate and expand a functionally superior Treg population and report on the effect of differing culture conditions. The relevance of Treg migratory capacity will also be discussed together with methods of in vivo visualization of the infused cells. Moreover, we will highlight key advances in the identification and expansion of antigen specific Tregs and discuss their significance for cell therapy application. We will also summarize the clinical parameters that are of importance, alongside cell manufacture, from the choice of immunosuppression regimens to the number of injections in order to direct the success of future efficacy trials of Treg cell therapy.Years of research in the field of tolerance have seen an accumulation of knowledge and expertise in the field of Treg biology. This perpetual progression has been the driving force behind the many successes to date and has put us now within touching distance of our ultimate success, immunological tolerance.

  1. Fault tolerant controllers for sampled-data systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob

    2004-01-01

    A general compensator architecture for fault tolerant control (FTC) for sampled-data systems is proposed. The architecture is based on the YJBK parameterization of all stabilizing controllers, and uses the dual YJBK parameterization to quantify the performance of the fault tolerant system. The FTC...

  2. Fault tolerant control for uncertain systems with parametric faults

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2006-01-01

    A fault tolerant control (FTC) architecture based on active fault diagnosis (AFD) and the YJBK (Youla, Jarb, Bongiorno and Kucera)parameterization is applied in this paper. Based on the FTC architecture, fault tolerant control of uncertain systems with slowly varying parametric faults...... is investigated. Conditions are given for closed-loop stability in case of false alarms or missing fault detection/isolation....

  3. Regulatory Control of Radiation Sources. Safety Guide (Arabic Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    This Safety Guide is intended to assist States in implementing the requirements established in Safety Standards Series No. GS-R-1, Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety, for a national regulatory infrastructure to regulate any practice involving radiation sources in medicine, industry, research, agriculture and education. The Safety Guide provides advice on the legislative basis for establishing regulatory bodies, including the effective independence of the regulatory body. It also provides guidance on implementing the functions and activities of regulatory bodies: the development of regulations and guides on radiation safety; implementation of a system for notification and authorization; carrying out regulatory inspections; taking necessary enforcement actions; and investigating accidents and circumstances potentially giving rise to accidents. The various aspects relating to the regulatory control of consumer products are explained, including justification, optimization of exposure, safety assessment and authorization. Guidance is also provided on the organization and staffing of regulatory bodies. Contents: 1. Introduction; 2. Legal framework for a regulatory infrastructure; 3. Principal functions and activities of the regulatory body; 4. Regulatory control of the supply of consumer products; 5. Functions of the regulatory body shared with other governmental agencies; 6. Organization and staffing of the regulatory body; 7. Documentation of the functions and activities of the regulatory body; 8. Support services; 9. Quality management for the regulatory system.

  4. Fault tolerant control schemes using integral sliding modes

    CERN Document Server

    Hamayun, Mirza Tariq; Alwi, Halim

    2016-01-01

    The key attribute of a Fault Tolerant Control (FTC) system is its ability to maintain overall system stability and acceptable performance in the face of faults and failures within the feedback system. In this book Integral Sliding Mode (ISM) Control Allocation (CA) schemes for FTC are described, which have the potential to maintain close to nominal fault-free performance (for the entire system response), in the face of actuator faults and even complete failures of certain actuators. Broadly an ISM controller based around a model of the plant with the aim of creating a nonlinear fault tolerant feedback controller whose closed-loop performance is established during the design process. The second approach involves retro-fitting an ISM scheme to an existing feedback controller to introduce fault tolerance. This may be advantageous from an industrial perspective, because fault tolerance can be introduced without changing the existing control loops. A high fidelity benchmark model of a large transport aircraft is u...

  5. Fault tolerant digital control systems for boiling water reactors

    International Nuclear Information System (INIS)

    Chakraborty, S.; Cash, N.R.

    1986-01-01

    In a Boiling Water Reactor nuclear power plant, the power generation control function is divided into several systems, each system controlling only a part of the total plant. Presently, each system is controlled by conventional analog or digital logic circuits with little interaction for coordinated control. The advent of microprocessors has allowed the development of distributed fault-tolerant digital controls. The objective is to replace these conventional controls with fault-tolerant digital controls connected together with digital communication links to form a fully integrated nuclear power plant control system

  6. Regulatory T cells, maternal-foetal immune tolerance and recurrent miscarriage: new therapeutic challenging opportunities.

    Science.gov (United States)

    Alijotas-Reig, Jaume; Melnychuk, Taisiia; Gris, Josep Maria

    2015-03-15

    Because maternal alloreactive lymphocytes are not depleted during pregnancy, local and/or systemic mechanisms have to play a key role in altering the maternal immune response. Peripheral T regulatory cells (pTregs) at the maternal-foetal interface are necessary in situ to prevent early abortion, but only those pTregs that have been previously exposed to paternal alloantigens. It has been showed that pregnancy selectively stimulates the accumulation of maternal Foxp3(+)CD4(+)CD25(+) (Foxp3Tregs) cells with foetal specificity. Interestingly, after delivery, foetal-specific pTregs persist at elevated levels, maintain tolerance to pre-existing foetal antigen, and rapidly re-accumulate during subsequent pregnancy. pTreg up-regulation could be hypothesized as a possible future therapeutic strategy in humans. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  7. Differential sensitivity of regulatory and effector T cells to cell death: a prerequisite for transplant tolerance

    Directory of Open Access Journals (Sweden)

    Sylvaine eYou

    2015-05-01

    Full Text Available Despite significant progress achieved in transplantation, immunosuppressive therapies currently used to prevent graft rejection are still endowed with severe side effects impairing their efficiency over the long term. Thus, the development of graft-specific, non toxic innovative therapeutic strategies has become a major challenge, the goal being to selectively target alloreactive effector T cells while sparing CD4+Foxp3+ regulatory T cells (Tregs to promote operational tolerance. Various approaches, notably the one based on monoclonal antibodies or fusion proteins directed against the TCR/CD3 complex, TCR coreceptors, or costimulatory molecules, have been proposed to reduce the alloreactive T cell pool which is an essential prerequisite to create a therapeutic window allowing Tregs to induce and maintain allograft tolerance. In this minireview, we focus on the differential sensitivity of Tregs and effector T cells to the depleting and inhibitory effect of these immunotherapies, with a particular emphasis on CD3-specific antibodies that beyond their immunosuppressive effect, also express potent tolerogenic capacities.

  8. Regulatory issues of digital instrumentation and control system in Lungmen project

    International Nuclear Information System (INIS)

    Chuang, C.F.; Chou, H.P.

    2004-01-01

    The Lungmen Nuclear Power Station (LNPS) is currently under construction in Taiwan, which consists of 2 advanced boiling water reactor (ABWR) units. The instrumentation and control (IC) systems of the LNPS are based on the state-of-the-art modernized fully integrated digital design. These IC systems possess many advantages and distinguished features comparing to traditional analog IC systems, they enjoy set-point stability, self-diagnostic and automatic testing ability, fault tolerance and avoidance, low power requirements, data handling and storage capability, as well as enhanced human-machine interfaces. This paper presents regulatory overviews, regulatory requirements, current major regulatory issues, as well as the areas of regulatory concerns and the lessons learned on the digital IC systems in the Lungmen Project

  9. Increased degradation of ATP is driven by memory regulatory T cells in kidney transplantation tolerance.

    Science.gov (United States)

    Durand, Maxim; Dubois, Florian; Dejou, Cécile; Durand, Eugénie; Danger, Richard; Chesneau, Mélanie; Brosseau, Carole; Guerif, Pierrick; Soulillou, Jean-Paul; Degauque, Nicolas; Eliaou, Jean-François; Giral, Magali; Bonnefoy, Nathalie; Brouard, Sophie

    2018-05-01

    Regulatory T cells were recently proposed as the central actor in operational tolerance after renal transplantation. Tolerant patients harbor increased FoxP3hi memory Treg frequency and increased demethylation in the Foxp3 Treg-specific demethylated region when compared to stable kidney recipients and exhibit greater memory Treg suppressive capacities and higher expression of the ectonucleotidase CD39. However, in this particular and unique situation the mechanisms of action of Tregs were not identified. Thus, we analyzed the ability of memory Tregs to degrade extracellular ATP in tolerant patients, healthy volunteers, and patients with stable graft function under immunosuppression and determined the role of immunosuppressive drugs on this process. The conserved proportion of memory Tregs leads to the establishment of a pro-tolerogenic balance in operationally tolerant patients. Memory Tregs in tolerant patients display normal capacity to degrade extracellular ATP/ADP. In contrast, memory Tregs from patients with stable graft function do not have this ability. Finally, in vitro, immunosuppressive drugs may favor the lower proportion of memory Tregs in stable patients, but they have no effect on CD39-dependent ATP degradation and do not explain memory Treg lack of extracellular ATP/ADP degradation ability. Thus, intrinsic active regulatory mechanisms may act long after immunosuppressive drug arrest in operationally tolerant patients and may contribute to kidney allograft tolerance via the maintenance of CD39 Treg function. Copyright © 2018 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  10. Fault tolerance and reliability in integrated ship control

    DEFF Research Database (Denmark)

    Nielsen, Jens Frederik Dalsgaard; Izadi-Zamanabadi, Roozbeh; Schiøler, Henrik

    2002-01-01

    Various strategies for achieving fault tolerance in large scale control systems are discussed. The positive and negative impacts of distribution through network communication are presented. The ATOMOS framework for standardized reliable marine automation is presented along with the corresponding...

  11. Passive Fault tolerant Control of an Inverted Double Pendulum

    DEFF Research Database (Denmark)

    Niemann, H.; Stoustrup, Jakob

    2003-01-01

    A passive fault tolerant control scheme is suggested, in which a nominal controller is augmented with an additional block, which guarantees stability and performance after the occurrence of a fault. The method is based on the Youla parameterization, which requires the nominal controller to be imp......A passive fault tolerant control scheme is suggested, in which a nominal controller is augmented with an additional block, which guarantees stability and performance after the occurrence of a fault. The method is based on the Youla parameterization, which requires the nominal controller...

  12. Safety culture as a matter of regulatory control and regulatory effectiveness

    International Nuclear Information System (INIS)

    Camargo, C.T.M.; Furieri, E.B.; Arrieta, L.A.I.; Almeida, C.U.C.

    2002-01-01

    More than 15 years have passed since the term 'safety culture' was introduced by the International Nuclear Safety Advisory Group (INSAG), and although the concept now is widely accepted, practical applications and characteristics have been disseminated mainly for nuclear power plant operating organizations. There is still a lack of international guidance on the use of safety culture as a regulatory matter and on the application of the concept within regulatory organizations. This work explores the meaning of safety culture in two different fields: as an element of safety management systems it shall be a matter of regulatory control; as a complementary tool for quality management it should be used to enhance regulatory effectiveness. Brazilian recent experience on regulating nuclear power reactors provide some examples on how the concept of safety culture may influence regulatory strategies and regulatory management. (author)

  13. Removal of regulatory controls for materials and sites

    International Nuclear Information System (INIS)

    2004-01-01

    Issues with the removal of regulatory controls are very important on the agenda of the regulatory authorities dealing with radioactive waste management (RWM). These issues arise prominently in decommissioning and in site remediation, and decisions can be very wide ranging having potentially important economic impacts and reaching outside the RWM area. The RWMC Regulators Forum started to address these issues by holding a topical discussion at its meeting in March 2003. Ths present document collates the national regulatory positions in the area of removal of regulatory controls. A summary of the national positions is also provided. The document is up to date to April 2004. (authors)

  14. Concepts and Methods in Fault-tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Staroswiecly, M.; Wu, N.E.

    2001-01-01

    Faults in automated processes will often cause undesired reactions and shut-down of a controlled plant, and the consequences could be damage to technical parts of the plant, to personnel or the environment. Fault-tolerant control combines diagnosis with control methods to handle faults...

  15. Regulatory controls for NORM contamination: Emerging issues and strategies

    International Nuclear Information System (INIS)

    Wennerberg, Linda

    1992-01-01

    Naturally occurring and accelerator-produced radioactive material (NORM) faces the increasing likelihood of federal or state regulatory control. Public concern and limited preliminary survey data fuel the debate over the necessity, approach, and jurisdiction of a NORM regulatory strategy. This debate requires the resolution of technical controversies and potentially competing state and federal agency interests. An additional facet of the debate is the impact of regulation upon traditionally non-nuclear industries, such as oil and gas production. Regulatory response has been initiated in several states, such as Louisiana's controls on equipment used in oil and gas production, to control specific industrial activities which generate NORM. A more comprehensive, generic federal strategy to control NORM contamination is also under review by the Environmental Protection Agency. This paper will detail the emerging technical issues, federal and state regulatory strategies under consideration, and evaluate the efficacy of selected regulatory approaches. (author)

  16. Real-time fault diagnosis and fault-tolerant control

    OpenAIRE

    Gao, Zhiwei; Ding, Steven X.; Cecati, Carlo

    2015-01-01

    This "Special Section on Real-Time Fault Diagnosis and Fault-Tolerant Control" of the IEEE Transactions on Industrial Electronics is motivated to provide a forum for academic and industrial communities to report recent theoretic/application results in real-time monitoring, diagnosis, and fault-tolerant design, and exchange the ideas about the emerging research direction in this field. Twenty-three papers were eventually selected through a strict peer-reviewed procedure, which represent the mo...

  17. The role of Foxp3+ regulatory T cells in liver transplant tolerance.

    Science.gov (United States)

    Li, W; Carper, K; Zheng, X X; Kuhr, C S; Reyes, J D; Liang, Y; Perkins, D L; Thomson, A W; Perkins, J D

    2006-12-01

    The liver has long been considered a tolerogenic organ that favors the induction of peripheral tolerance. The mechanisms underlying liver tolerogenicity remain largely undefined. In this study, we characterized Foxp3-expressing CD4+ CD25+ regulatory T cells (Treg) in liver allograft recipients and examined the role of Treg in inherent liver tolerogenicity by employing the mouse spontaneous liver transplant tolerance model. Orthotopic liver transplantation was performed from C57BL/10 (H2b) to C3H/HeJ (H2k) mice. The percentage of CD4+ CD25+ Treg was expanded in the liver grafts and recipient spleens from day 5 up to day 100 posttransplantation, associated with high intracellular Foxp3 and CTLA4 expression. Immunohistochemistry further demonstrated significant numbers of Foxp3+ cells in the liver grafts and recipient spleens and increased transforming growth factor beta expression in the recipient spleens throughout the time courses. Adoptive transfer of spleen cells from the long-term liver allograft survivors significantly prolonged donor heart graft survival. Depletion of recipient CD4+ CD25+ Treg using anti-CD25 monoclonal antibody (250 microg/d) induced acute liver allograft rejection, associated with elevated anti-donor T-cell proliferative responses, CTL and natural killer activities, enhanced interleukin (IL)-2, interferon-gamma, IL-10, and decreased IL-4 production, and decreased T-cell apoptotic activity in anti-CD25-treated recipients. Moreover, CTLA4 blockade by anti-CTLA4 monoclonal antibody administration exacerbated liver graft rejection when combined with anti-CD25 monoclonal antibody. Thus, Foxp3+ CD4+ CD25+ Treg appear to underpin spontaneous acceptance of major histocompatability complex- mismatched liver allografts in mice. CTLA4, IL-4, and apoptosis of alloreactive T cells appear to contribute to the function of Treg and regulation of graft outcome.

  18. Moving through the stressed genome: Emerging regulatory roles for transposons in plant stress tolerance

    Directory of Open Access Journals (Sweden)

    Negi Pooja

    2016-10-01

    Full Text Available The recognition of a positive correlation between organism genome size with its transposable element (TE content, represents a key discovery of the field of genome biology. Considerable evidence accumulated since then suggests the involvement of TEs in genome structure, evolution and function. The global genome reorganization brought about by transposon activity might play an adaptive/regulatory role in the host response to environmental challenges, reminiscent of McClintock’s original ’Controlling Element’ hypothesis. This regulatory aspect of TEs is also garnering support in light of the recent evidences which project TEs as distributed genomic control modules. According to this view, TEs are capable of actively reprogramming host genes circuits and ultimately fine-tuning the host response to specific environmental stimuli. Moreover, the stress-induced changes in epigenetic status of TE activity may allow TEs to propagate their stress responsive elements to host genes; the resulting genome fluidity can permit phenotypic plasticity and adaptation to stress. Given their predominating presence in the plant genomes, nested organization in the genic regions and potential regulatory role in stress response, TEs hold unexplored potential for crop improvement programs. This review intends to present the current information about the roles played by TEs in plant genome organization, evolution and function, and highlight the regulatory mechanisms in plant stress responses. We will also briefly discuss the connection between TE activity, host epigenetic response and phenotypic plasticity as a critical link for traversing the translational bridge from a purely basic study of TEs, to the applied field of stress adaptation and crop improvement.

  19. Classical dendritic cells are required for dietary antigen-mediated peripheral regulatory T cell and tolerance induction

    Science.gov (United States)

    Esterházy, Daria; Loschko, Jakob; London, Mariya; Jove, Veronica; Oliveira, Thiago Y.; Mucida, Daniel

    2016-01-01

    Oral tolerance prevents pathological inflammatory responses towards innocuous foreign antigens via peripheral regulatory T cells (pTreg cells). However, whether a particular subset of antigen-presenting cells (APCs) is required during dietary antigen exposure to instruct naïve CD4+ T cells to differentiate into pTreg cells has not been defined. Using myeloid lineage-specific APC depletion in mice, we found that monocyte-derived APCs are dispensable, while classical dendritic cells (cDCs) are critical for pTreg cell induction and oral tolerance. CD11b− cDCs from the gut-draining lymph nodes efficiently induced pTreg cells, and conversely, loss of IRF8-dependent CD11b− cDCs impaired their polarization, although oral tolerance remained intact. These data reveal the hierarchy of cDC subsets in pTreg cell induction and their redundancy during oral tolerance development. PMID:27019226

  20. Regulatory accessibility and social influences on state self-control.

    Science.gov (United States)

    vanDellen, Michelle R; Hoyle, Rick H

    2010-02-01

    The current work examined how social factors influence self-control. Current conceptions of state self-control treat it largely as a function of regulatory capacity. The authors propose that state self-control might also be influenced by social factors because of regulatory accessibility. Studies 1 through 4 provide evidence that individuals' state self-control is influenced by the trait and state self-control of salient others such that thinking of others with good trait or state self-control leads to increases in state self-control and thinking of others with bad trait or state self-control leads to decreases in state self-control. Study 5 provides evidence that the salience of significant others influences both regulatory accessibility and state self-control. Combined, these studies suggest that the effects of social influences on state self-control occur through multiple mechanisms.

  1. Regulatory control of physical protection systems

    International Nuclear Information System (INIS)

    Rajdeep; Mayya, Y.S.

    2017-01-01

    The safety of facilities in BARC is under the regulatory oversight of BSC. The security architecture for these facilities incorporates multiple layers of Physical Protection Systems. The demands of safety may sometimes conflict with the needs of security. Realizing the need to identify these interfaces and extend the regulatory coverage to Physical Protection Systems, a Standing Committee named Physical Protection System Review Committee (PPSRC) has been constituted as a 2"n"d tier entity of BSC. PPSRC includes experts from various domains concerned with nuclear security, viz. physical protection systems, cyber security, radiation safety, security operations, technical services and security administration

  2. Autonomous Congestion Control in Delay-Tolerant Networks

    Science.gov (United States)

    Burleigh, Scott; Jennings, Esther; Schoolcraft, Joshua

    2006-01-01

    This presentation highlights communication congestion control in delay-tolerant networks (DTNs). Large-scale future space exploration will offer complex communication challenges that may be best addressed by establishing a network infrastructure. However, current internet techniques for congestion control are not well suited for operation of a network over interplanetary distances. An alternative, delay-tolerant technique for congestion control in a delay-tolerant network is presented. A simple DTN was constructed and an experimental congestion control mechanism was applied. The mechanism appeared to be effective and each router was able to make its bundle acceptance decisions autonomously. Future research will examine more complex topologies and alternative bundle acceptance rules that might enhance performance.

  3. Active Fault Tolerant Control of Livestock Stable Ventilation System

    DEFF Research Database (Denmark)

    Gholami, Mehdi

    2011-01-01

    Modern stables and greenhouses are equipped with different components for providing a comfortable climate for animals and plant. A component malfunction may result in loss of production. Therefore, it is desirable to design a control system, which is stable, and is able to provide an acceptable d...... are not included, while due to the physical limitation, the input signal can not have any value. In continuing, a passive fault tolerant controller (PFTC) based on state feedback is proposed to track a reference signal while the control inputs are bounded....... of fault. Designing a fault tolerant control scheme for the climate control system. In the first step, a conceptual multi-zone model for climate control of a live-stock building is derived. The model is a nonlinear hybrid model. Hybrid systems contain both discrete and continuous components. The parameters...... affine (PWA) components such as dead-zones, saturation, etc or contain piecewise nonlinear models which is the case for the climate control systems of the stables. Fault tolerant controller (FTC) is based on a switching scheme between a set of predefined passive fault tolerant controller (PFTC...

  4. Regulatory control, nuclear safety regulation and waste management in Spain

    International Nuclear Information System (INIS)

    Martin, A.

    2000-01-01

    This article presents the challenges that faces the spanish regulatory authority. The deregulation of electricity industry imposes severe changes in nuclear power economics and forces nuclear power to compete with other sources of electricity. A pressure is perceived for regulatory effectiveness primarily since the cost of regulation is a component of the cost of the product. This effectiveness gain in regulatory control will be reached through systematic strategic analysis, formulation and implementation. The regulatory aspects of plant life extension and of waste management are examined

  5. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    is linked to a different set of circumstances than the ones suggested by existing models in contemporary democratic theory. Reorienting the discussion of tolerance, the book raises the question of how to disclose new possibilities within our given context of affect and perception. Once we move away from......Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated...... by the desire to experiment and to become otherwise. The objective is to discuss what gets lost, conceptually as well as politically, when we neglect the subsistence of active tolerance within other practices of tolerance, and to develop a theory of active tolerance in which tolerance's mobilizing character...

  6. Design of fault tolerant control system for steam generator using

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Ki; Seo, Mi Ro [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    A controller and sensor fault tolerant system for a steam generator is designed with fuzzy logic. A structure of the proposed fault tolerant redundant system is composed of a supervisor and two fuzzy weighting modulators. A supervisor alternatively checks a controller and a sensor induced performances to identify which part, a controller or a sensor, is faulty. In order to analyze controller induced performance both an error and a change in error of the system output are chosen as fuzzy variables. The fuzzy logic for a sensor induced performance uses two variables : a deviation between two sensor outputs and its frequency. Fuzzy weighting modulator generates an output signal compensated for faulty input signal. Simulations show that the proposed fault tolerant control scheme for a steam generator regulates well water level by suppressing fault effect of either controllers or sensors. Therefore through duplicating sensors and controllers with the proposed fault tolerant scheme, both a reliability of a steam generator control and sensor system and that of a power plant increase even more. 2 refs., 9 figs., 1 tab. (Author)

  7. A Ship Propulsion System Model for Fault-tolerant Control

    DEFF Research Database (Denmark)

    Izadi-Zamanabadi, Roozbeh; Blanke, M.

    This report presents a propulsion system model for a low speed marine vehicle, which can be used as a test benchmark for Fault-Tolerant Control purposes. The benchmark serves the purpose of offering realistic and challenging problems relevant in both FDI and (autonomous) supervisory control area...

  8. Fault Tolerant Control of Wind Turbines

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Kinnaert, Michel

    2013-01-01

    This paper presents a test benchmark model for the evaluation of fault detection and accommodation schemes. This benchmark model deals with the wind turbine on a system level, and it includes sensor, actuator, and system faults, namely faults in the pitch system, the drive train, the generator......, and the converter system. Since it is a system-level model, converter and pitch system models are simplified because these are controlled by internal controllers working at higher frequencies than the system model. The model represents a three-bladed pitch-controlled variable-speed wind turbine with a nominal power...

  9. Fault Tolerant Autonomous Lateral Control for Heavy Vehicles

    OpenAIRE

    Talbot, Craig Matthew; Papadimitriou, Iakovos; Tomizuka, Masayoshi

    2004-01-01

    This report summarizes the research results of TO4233, "Fault Tolerant Autonomous Lateral Control for Heavy Vehicles". This project represents a continuing effort of PATH's research on Automated Highway Systems (AHS) and more specifically in the area of heavy vehicles. Research on the lateral control of heavy vehicles for AHS has been going on at PATH since 1993. MOU129, "Steering and Braking Control of Heavy Duty Vehicles" was the first project and it was followed by MOU242, "Lateral Control...

  10. Mine-hoist active fault tolerant control system and strategy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.; Wang, Y.; Meng, J.; Zhao, P.; Chang, Y. [China University of Mining and Technology, Xuzhou (China)] wzjsdstu@163.com

    2005-06-01

    Based on fault diagnosis and fault tolerant technologies, the mine-hoist active fault-tolerant control system (MAFCS) is presented with corresponding strategies, which includes the fault diagnosis module (FDM), the dynamic library (DL) and the fault-tolerant control model (FCM). When a fault is judged from some sensor by the FDM, FCM reconfigures the state of the MAFCS by calling the parameters from all sub libraries in DL, in order to ensure the reliability and safety of the mine hoist. The simulating result shows that MAFCS is of certain intelligence, which can adopt the corresponding control strategies according to different fault modes, even when there is quite a difference between the real data and the prior fault modes. 7 refs., 5 figs., 1 tab.

  11. The regulatory control of radioactive sources in Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Rojkind, Roberto Hector [Autoridade Regulatoria Nuclear, Buenos Aires (Argentina)

    1997-12-31

    Argentina has been conducting nuclear activities for more than forty years, and as early as in 1956 established a Regulatory Authority. Procedures for compliance monitoring and enforcement have been in use in the regulatory control of radioactive sources, and regulatory standards and regulations had been set in Argentina, before the accident in Goiania. The conclusions drawn from that accident encouraged in Argentina the improvement of some regulatory procedures and helped to enhance the quality of the regulatory process. Therefore, the effectiveness of the control of spent radioactive sources has gradually increased, and enforcement actions to prevent radioactive sources ending up in the public domain improved. Some lessons learned in Argentina from the accident in Goiania and the main characteristics of an effective enforcement program helpful to prevent radiological accidents in industrial, medical, research and teaching uses of radioactive sources are presented. (author) 9 refs; e-mail: rrojkind at sede.arn.gov.br

  12. The regulatory control of radioactive sources in Argentina

    International Nuclear Information System (INIS)

    Rojkind, R.H.

    1998-01-01

    Argentina has been conducting nuclear activities for more than forty years, and had established a Regulatory Authority as early as in 1956. Procedures for compliance monitoring and enforcement have been in use in the regulatory control of radioactive sources, and regulatory standards and regulations were in force in Argentina before the accident in Goiania. The conclusions drawn from the Goiania accident encouraged the Argentine authorities to improve some regulatory procedures and helped to enhance the quality of the regulatory process. As a result, the effectiveness of the control of spent radioactive sources has gradually increased, and enforcement actions to prevent radioactive sources ending up in the public domain have improved. Lessons learned in Argentina from the accident in Goiania are presented as well as the main characteristics of an effective enforcement programme to prevent radiological accidents when radioactive sources are used for industrial, medical, research and teaching purposes. (author)

  13. The regulatory control of radioactive sources in Argentina

    International Nuclear Information System (INIS)

    Rojkind, Roberto Hector

    1997-01-01

    Argentina has been conducting nuclear activities for more than forty years, and as early as in 1956 established a Regulatory Authority. Procedures for compliance monitoring and enforcement have been in use in the regulatory control of radioactive sources, and regulatory standards and regulations had been set in Argentina, before the accident in Goiania. The conclusions drawn from that accident encouraged in Argentina the improvement of some regulatory procedures and helped to enhance the quality of the regulatory process. Therefore, the effectiveness of the control of spent radioactive sources has gradually increased, and enforcement actions to prevent radioactive sources ending up in the public domain improved. Some lessons learned in Argentina from the accident in Goiania and the main characteristics of an effective enforcement program helpful to prevent radiological accidents in industrial, medical, research and teaching uses of radioactive sources are presented. (author)

  14. Fault-tolerant Control of a Cyber-physical System

    Science.gov (United States)

    Roxana, Rusu-Both; Eva-Henrietta, Dulf

    2017-10-01

    Cyber-physical systems represent a new emerging field in automatic control. The fault system is a key component, because modern, large scale processes must meet high standards of performance, reliability and safety. Fault propagation in large scale chemical processes can lead to loss of production, energy, raw materials and even environmental hazard. The present paper develops a multi-agent fault-tolerant control architecture using robust fractional order controllers for a (13C) cryogenic separation column cascade. The JADE (Java Agent DEvelopment Framework) platform was used to implement the multi-agent fault tolerant control system while the operational model of the process was implemented in Matlab/SIMULINK environment. MACSimJX (Multiagent Control Using Simulink with Jade Extension) toolbox was used to link the control system and the process model. In order to verify the performance and to prove the feasibility of the proposed control architecture several fault simulation scenarios were performed.

  15. Fault diagnosis and fault-tolerant control based on adaptive control approach

    CERN Document Server

    Shen, Qikun; Shi, Peng

    2017-01-01

    This book provides recent theoretical developments in and practical applications of fault diagnosis and fault tolerant control for complex dynamical systems, including uncertain systems, linear and nonlinear systems. Combining adaptive control technique with other control methodologies, it investigates the problems of fault diagnosis and fault tolerant control for uncertain dynamic systems with or without time delay. As such, the book provides readers a solid understanding of fault diagnosis and fault tolerant control based on adaptive control technology. Given its depth and breadth, it is well suited for undergraduate and graduate courses on linear system theory, nonlinear system theory, fault diagnosis and fault tolerant control techniques. Further, it can be used as a reference source for academic research on fault diagnosis and fault tolerant control, and for postgraduates in the field of control theory and engineering. .

  16. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated by the d...... these alternatives by returning to the notion of tolerance as the endurance of pain, linking this notion to exemplars and theories relevant to the politics of multiculturalism, religious freedom, and free speech....

  17. Active Fault Tolerant Control for Ultrasonic Piezoelectric Motor

    Science.gov (United States)

    Boukhnifer, Moussa

    2012-07-01

    Ultrasonic piezoelectric motor technology is an important system component in integrated mechatronics devices working on extreme operating conditions. Due to these constraints, robustness and performance of the control interfaces should be taken into account in the motor design. In this paper, we apply a new architecture for a fault tolerant control using Youla parameterization for an ultrasonic piezoelectric motor. The distinguished feature of proposed controller architecture is that it shows structurally how the controller design for performance and robustness may be done separately which has the potential to overcome the conflict between performance and robustness in the traditional feedback framework. A fault tolerant control architecture includes two parts: one part for performance and the other part for robustness. The controller design works in such a way that the feedback control system will be solely controlled by the proportional plus double-integral PI2 performance controller for a nominal model without disturbances and H∞ robustification controller will only be activated in the presence of the uncertainties or an external disturbances. The simulation results demonstrate the effectiveness of the proposed fault tolerant control architecture.

  18. Regulatory control of maintenance activities in Argentine nuclear power plants

    International Nuclear Information System (INIS)

    Calvo, J.C.; Caruso, G.

    2000-01-01

    The main maintenance objective is to assure that the safety features of structures, components and systems of nuclear power plants are kept as designed. Therefore, there is a direct relationship between safety and maintenance. Owing to the above mentioned, maintenance activities are considered a relevant regulatory issue for the Argentine Nuclear Regulatory Authority (ARN). This paper describes the regulatory control to maintenance activities of Argentine nuclear power plants. It also addresses essential elements for maintenance control, routine inspections, special inspections during planned outages, audits and license conditions and requirements. (author)

  19. Flatness-based fault tolerant control

    Directory of Open Access Journals (Sweden)

    César Martínez-Torres

    2014-01-01

    Full Text Available Este artículo presenta un método de control tolerante a fallas para sistemas no lineales planos. Las propiedades intrínsecas d e los sistemas planos generan redundancia analítica y permiten calcular todos los estados y las entradas de control del sistema. Los residuo s son calculados comparando las medidas reales provenientes de los se nsores y las señales obtenidas gracias al conjunto de ecuacione s del sistema plano. Fallas multiplicativas y aditivas se pueden man ejar de manera indistinta. Las señales redundantes obtenidas co n las ecuaciones del sistema plano son usadas para reconfigurar el si stema con falla. La factibilidad del método propuesto es verifi cada para fallas aditivas en un sistema de tres tanques.

  20. Regulatory Accessibility and Social Influences on State Self-Control

    OpenAIRE

    vanDellen, Michelle R.; Hoyle, Rick H.

    2009-01-01

    The current work examined how social factors influence self-control. Current conceptions of state self-control treat it largely as a function of regulatory capacity. The authors propose that state self-control might also be influenced by social factors because of regulatory accessibility. Studies 1 through 4 provide evidence that individuals’ state self-control is influenced by the trait and state self-control of salient others such that thinking of others with good trait or state self-contro...

  1. Fault Tolerant Control System Design Using Automated Methods from Risk Analysis

    DEFF Research Database (Denmark)

    Blanke, M.

    Fault tolerant controls have the ability to be resilient to simple faults in control loop components.......Fault tolerant controls have the ability to be resilient to simple faults in control loop components....

  2. Regulatory control of radiation sources. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    The basic requirements for the protection of persons against exposure to ionizing radiation and for the safety of radiation sources were established in the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (the Basic Safety Standards), jointly sponsored by the Food and Agriculture Organization of the United Nations (FAO), the International Atomic Energy Agency (IAEA), the International Labour Organization (ILO), the OECD Nuclear Energy Agency (OECD/ NEA), the Pan American Health Organization (PAHO) and the World Health Organization (WHO) (the Sponsoring Organizations). The application of the Basic Safety Standards is based on the presumption that national infrastructures are in place to enable governments to discharge their responsibilities for radiation protection and safety. Requirements relating to the legal and governmental infrastructure for the safety of nuclear facilities and sources of ionizing radiation, radiation protection, the safe management of radioactive waste and the safe transport of radioactive material are established in the Safety Requirements on Legal and Governmental Infrastructure for Nuclear, Radiation, Radioactive Waste and Transport Safety, Safety Standards Series No. GS-R-1. This Safety Guide, which is jointly sponsored by the FAO, the IAEA, the International Labour Office, the PAHO and the WHO, gives detailed guidance on the key elements for the organization and operation of a national regulatory infrastructure for radiation safety, with particular reference to the functions of the national regulatory body that are necessary to ensure the implementation of the Basic Safety Standards. The Safety Guide is based technically on material first published in IAEA-TECDOC-10671, which was jointly sponsored by the FAO, the IAEA, the OECD/NEA, the PAHO and the WHO. The requirements established in GS-R-1 have been taken into account. The Safety Guide is oriented towards national

  3. Wind turbine fault detection and fault tolerant control

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Johnson, Kathryn

    2013-01-01

    In this updated edition of a previous wind turbine fault detection and fault tolerant control challenge, we present a more sophisticated wind turbine model and updated fault scenarios to enhance the realism of the challenge and therefore the value of the solutions. This paper describes...

  4. Data Driven Fault Tolerant Control : A Subspace Approach

    NARCIS (Netherlands)

    Dong, J.

    2009-01-01

    The main stream research on fault detection and fault tolerant control has been focused on model based methods. As far as a model is concerned, changes therein due to faults have to be extracted from measured data. Generally speaking, existing approaches process measured inputs and outputs either by

  5. Fault tolerant homopolar magnetic bearings with flux invariant control

    International Nuclear Information System (INIS)

    Na, Uhn Joo

    2006-01-01

    The theory for a novel fault-tolerant 4-active-pole homopolar magnetic bearing is developed. If any one coil of the four coils in the bearing actuator fail, the remaining three coil currents change via an optimal distribution matrix such that the same opposing pole, C-core type, control fluxes as those of the un-failed bearing are produced. The homopolar magnetic bearing thus provides unaltered magnetic forces without any loss of the bearing load capacity even if any one coil suddenly fails. Numerical examples are provided to illustrate the novel fault-tolerant, 4-active pole homopolar magnetic bearings

  6. Regulatory controls and slurry fracture injection

    International Nuclear Information System (INIS)

    Dusseault, M. B.; Bilak, R. A.

    1997-01-01

    The technological and regulatory framework necessary for the safe operation of solid waste disposal using slurry fracture injection (SFI) in Saskatchewan and Alberta was studied. Seven current SFI sites were used as the source of experience. Regular audits of volumes, continuous pressure recording, careful deformation monitoring and analysis, and repeated evaluation of reservoir properties were considered to be the essential features. In the case of toxic wastes, microseismic monitoring and regular well interference or tracer tests might be additional measures used to increase confidence in the containment method. Given the recent introduction of SFI technology, guarding against over-regulation was recommended to allow SFI to operate under the most effective operating conditions, and to preserve its attractiveness as an environmentally attractive and safe waste disposal alternative. 5 refs., 3 tabs., 4 figs

  7. Controlling the frontier: regulatory T-cells and intestinal homeostasis.

    Science.gov (United States)

    Bollrath, Julia; Powrie, Fiona M

    2013-11-30

    The intestine represents one of the most challenging sites for the immune system as immune cells must be able to mount an efficient response to invading pathogens while tolerating the large number and diverse array of resident commensal bacteria. Foxp3(+) regulatory T-cells (Tregs) play a non-redundant role at maintaining this balance. At the same time Treg cell differentiation and function can be modulated by the intestinal microbiota. In this review, we will discuss effector mechanisms of Treg cells in the intestine and how these cells can be influenced by the intestinal microbiota. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Licensing and regulatory control of nuclear power plants in Canada

    International Nuclear Information System (INIS)

    Atchison, R.J.

    1975-01-01

    The paper discusses the safety philosophy adopted in Canada, the safety criteria and regulatory requirements necessary for the application of this philosophy to reactor design and operation, and finally the means by which compliance with Board requirements is effected. It is emphasized that the effectiveness of regulatory control depends not only on the underlying philosophy but also on the detailed way in which it is applied. (orig./HP) [de

  9. Expression of cold and drought regulatory protein (CcCDR) of pigeonpea imparts enhanced tolerance to major abiotic stresses in transgenic rice plants.

    Science.gov (United States)

    Sunitha, Mellacheruvu; Srinath, Tamirisa; Reddy, Vudem Dashavantha; Rao, Khareedu Venkateswara

    2017-06-01

    Transgenic rice expressing pigeonpea Cc CDR conferred high-level tolerance to different abiotic stresses. The multiple stress tolerance observed in CcCDR -transgenic lines is attributed to the modulation of ABA-dependent and-independent signalling-pathway genes. Stable transgenic plants expressing Cajanus cajan cold and drought regulatory protein encoding gene (CcCDR), under the control of CaMV35S and rd29A promoters, have been generated in indica rice. Different transgenic lines of CcCDR, when subjected to drought, salt, and cold stresses, exhibited higher seed germination, seedling survival rates, shoot length, root length, and enhanced plant biomass when compared with the untransformed control plants. Furthermore, transgenic plants disclosed higher leaf chlorophyll content, proline, reducing sugars, SOD, and catalase activities, besides lower levels of MDA. Localization studies revealed that the CcCDR-GFP fusion protein was mainly present in the nucleus of transformed cells of rice. The CcCDR transgenics were found hypersensitive to abscisic acid (ABA) and showed reduced seed germination rates as compared to that of control plants. When the transgenic plants were exposed to drought and salt stresses at vegetative and reproductive stages, they revealed larger panicles and higher number of filled grains compared to the untransformed control plants. Under similar stress conditions, the expression levels of P5CS, bZIP, DREB, OsLEA3, and CIPK genes, involved in ABA-dependent and-independent signal transduction pathways, were found higher in the transgenic plants than the control plants. The overall results amply demonstrate that the transgenic rice expressing CcCDR bestows high-level tolerance to drought, salt, and cold stress conditions. Accordingly, the CcCDR might be deployed as a promising candidate gene for improving the multiple stress tolerance of diverse crop plants.

  10. Monitoring control program as a tool for regulatory control

    International Nuclear Information System (INIS)

    Silva Peres, Sueli da; Lauria, Dejanaira C.; Martins, Nadia S.F.; Rio, Monica A.P.

    2008-01-01

    Full text: The Institute of Radiation Protection and Dosimetry (IRD) of the Brazilian Commission of Nuclear Energy (CNEN) is responsible for developing, establishing and carrying out an independent assessment to verify the adequacy, effectiveness and accuracy of environmental radiological control carried out by licensed and controlled facilities. This independent assessment is performed by Environmental Monitoring Control Program (MCP). The MCP is a regulatory control and its main goal is to provide public and environment with an appropriate protection level against harmful effects of ionising radiation. The main purpose of the MCP is to verify whether applicable requirements prescribed by legislation are met, the environmental radiological control of the facilities are adequate and effective and the facilities are able to generate valid measuring results. The MCP is carried out in order to evaluate the quality of environmental radiation monitoring programs (EMP) and the effectiveness of their implementation, sampling conditions in the field, changes of environmental aspects in the impact area, adequacy of and adherence to procedures established and other applicable documents, technical competence of the staff and the necessary resources to ensure the required quality of the EMP. The MCP has been performed by activities should include inspecting and auditing of several types of nuclear and radioactive facilities. The inspection programme include the joint sampling program (CCP). The aim of the CCP is to check data of environmental monitoring of operator. The MCP was implemented in 1994. Ever since several problems related to the environmental control performed by operator was identified. The most important of them include problems related to the preparation and analysis of environmental samples, training of personnel, necessary resources, adherence of procedures to the purpose of the monitoring, fulfillment of procedures established, adequacy of the EMP and EMP

  11. Regulatory control of ionizing radiations in Ecuador

    International Nuclear Information System (INIS)

    Benitez, Manuel

    1996-03-01

    This document deals with legal aspects for controlling ionizing radiations, radiological safety regulations and objectives, scopes and features of the national radioprotection planning in Ecuador. (The author)

  12. Plant-based oral tolerance to hemophilia therapy employs a complex immune regulatory response including LAP+CD4+ T cells

    OpenAIRE

    Wang, Xiaomei; Su, Jin; Sherman, Alexandra; Rogers, Geoffrey L.; Liao, Gongxian; Hoffman, Brad E.; Leong, Kam W.; Terhorst, Cox; Daniell, Henry; Herzog, Roland W.

    2015-01-01

    Coadministering FIX orally and systemically induces tolerance via complex immune regulation, involving tolerogenic dendritic and T-cell subsets.Induced CD4+CD25−LAP+ regulatory T cells with increased IL-10 and TGF-β expression and CD4+CD25+ regulatory T cells suppress antibody formation against FIX.

  13. Regulatory control of the use of contractors by operating organizations. Peer discussions on regulatory practices

    International Nuclear Information System (INIS)

    2000-09-01

    This report arises from the eighth series of peer discussions on regulatory practices entitled 'Regulatory control of the use of contractors by operating organizations'. Senior regulators from 19 Member States participated in two peer group discussions in March 2000 and May 2000. This report gives an account of the outcomes of these meetings and of practical suggestions put forward by senior regulators. These suggestions do not necessarily reflect the views of the governments of the nominating Member States, the organizations they belong to, or the International Atomic Energy Agency. The objective of this document is to share experience between regulatory bodies and provide practical suggestions for controlling the use of contractors and subcontractors by the operating organizations during all stages, especially operation, of a nuclear power plant, so as to ensure that the quality of work and services delivered is commensurate with the safety importance of the activities and that these are carried out in a manner that will not adversely affect the safe or reliable operation of the facility. These documented practical suggestions and experiences are the result of a series of peer discussions at the IAEA in 2000. It is considered that the manner in which control is exercised, and the various challenges connected to this control, are highly dependent upon the legislative framework, maturity of the nuclear programme, the size of the national nuclear industry and the culture in each country. The report is structured so that it covers the subject matter under the following main headings: Legal Provisions, Regulatory Strategy and Requirements; Regulatory Approaches for Controlling the Use of Contractors; Types of Contracts; Practical Suggestions

  14. Reliable, fault tolerant control systems for nuclear generating stations

    International Nuclear Information System (INIS)

    McNeil, T.O.; Olmstead, R.A.; Schafer, S.

    1990-01-01

    Two operational features of CANDU Nuclear Power Stations provide for high plant availability. First, the plant re-fuels on-line, thereby eliminating the need for periodic and lengthy refuelling 'outages'. Second, the all plants are controlled by real-time computer systems. Later plants are also protected using real-time computer systems. In the past twenty years, the control systems now operating in 21 plants have achieved an availability of 99.8%, making significant contributions to high CANDU plant capacity factors. This paper describes some of the features that ensure the high degree of system fault tolerance and hence high plant availability. The emphasis will be placed on the fault tolerant features of the computer systems included in the latest reactor design - the CANDU 3 (450MWe). (author)

  15. Development and Evaluation of Fault-Tolerant Flight Control Systems

    Science.gov (United States)

    Song, Yong D.; Gupta, Kajal (Technical Monitor)

    2004-01-01

    The research is concerned with developing a new approach to enhancing fault tolerance of flight control systems. The original motivation for fault-tolerant control comes from the need for safe operation of control elements (e.g. actuators) in the event of hardware failures in high reliability systems. One such example is modem space vehicle subjected to actuator/sensor impairments. A major task in flight control is to revise the control policy to balance impairment detectability and to achieve sufficient robustness. This involves careful selection of types and parameters of the controllers and the impairment detecting filters used. It also involves a decision, upon the identification of some failures, on whether and how a control reconfiguration should take place in order to maintain a certain system performance level. In this project new flight dynamic model under uncertain flight conditions is considered, in which the effects of both ramp and jump faults are reflected. Stabilization algorithms based on neural network and adaptive method are derived. The control algorithms are shown to be effective in dealing with uncertain dynamics due to external disturbances and unpredictable faults. The overall strategy is easy to set up and the computation involved is much less as compared with other strategies. Computer simulation software is developed. A serious of simulation studies have been conducted with varying flight conditions.

  16. Fault tolerant control for steam generators in nuclear power plant

    International Nuclear Information System (INIS)

    Deng Zhihong; Shi Xiaocheng; Xia Guoqing; Fu Mingyu

    2010-01-01

    Based on the nonlinear system with stochastic noise, a bank of extended Kalman filters is used to estimate the state of sensors. It can real-time detect and isolate the single sensor fault, and reconstruct the sensor output to keep steam generator water level stable. The simulation results show that the methodology of employing a bank of extended Kalman filters for steam generator fault tolerant control design is feasible. (authors)

  17. Cold plasma: Quality control and regulatory considerations

    Science.gov (United States)

    In recent years, cold plasma has emerged as a promising antimicrobial treatment for fresh and fresh-cut produce, nuts, spices, seeds, and other foods. Research has demonstrated effective control of human pathogens such as Salmonella, Listeria monocytogenes, Escherichia coli O157:H7, norovirus, and o...

  18. The regulatory maze of quality control

    International Nuclear Information System (INIS)

    Stone, T.I.

    1987-01-01

    The appropriateness of specific procedures within a quality control program becomes difficult to assess when an attempt is made to collate all of the available information. This task is discussed from the perspective of the Joint Commission (JCAH Accreditation Manual), HHS(quality assurance program recommendations), equipment manufacturers maintenance schedules, and radiology administrative cost concerns

  19. Regulatory perspective on incomplete control rod insertions

    International Nuclear Information System (INIS)

    Chatterton, M.

    1997-01-01

    The incomplete control rod insertions experienced at South Texas Unit 1 and Wolf Creek are of safety concern to the NRC staff because they represent potential precursors to loss of shutdown margin. Even before it was determined if these events were caused by the control rods or by the fuel there was an apparent correlation of the problem with high burnup fuel. It was determined that there was also a correlation between high burnup and high drag forces as well as with rod drop time histories and lack of rod recoil. The NRC staff initial actions were aimed at getting a perspective on the magnitude of the problem as far as the number of plants and the amount of fuel that could be involved, as well as the safety significance in terms of shutdown margin. As tests have been performed and data has been analyzed the focus has shifted more toward understanding the problem and the ways to eliminate it. At this time the staff's understanding of the phenomena is that it was a combination of factors including burnup, power history and temperature. The problem appears to be very sensitive to these factors, the interaction of which is not clearly understood. The model developed by Westinghouse provides a possible explanation but there is not sufficient data to establish confidence levels and sensitivity studies involving the key parameters have not been done. While several fixes to the problem have been discussed, no definitive fixes have been proposed. Without complete understanding of the phenomena, or fixes that clearly eliminate the problem the safety concern remains. The safety significance depends on the amount of shutdown margin lost due to incomplete insertion of the control rods. Were the control rods to stick high in the core, the reactor could not be shutdown by the control rods and other means such as emergency boration would be required

  20. Induced Foxp3+ T cells colonising tolerated allografts exhibit the hypomethylation pattern typical of mature regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Robert eHilbrands

    2016-04-01

    Full Text Available Regulatory T cells expressing the transcription factor Foxp3 require acquisition of a specific hypomethylation pattern to ensure optimal functional commitment, limited lineage plasticity and long-term maintenance of tolerance. A better understanding of the molecular mechanisms involved in the generation of these epigenetic changes in vivo will contribute to the clinical exploitation of Foxp3+Treg. Here we show that both in vitro and in vivo generated antigen specific Foxp3+Treg can acquire Treg-specific epigenetic characteristics and prevent skin graft rejection in an animal model.

  1. Regulatory control of radiation sources in the Philippines

    International Nuclear Information System (INIS)

    Daroy, Rosita R.

    1995-01-01

    This paper is concerned with the radiation protection and safety infrastructure providing emphasis on the regulation and control of radiation sources in the Philippines. It deals with the experiences of the Philippine Nuclear Research Institute, as a regulatory body, in the regulation and control of radioactive materials in radiotherapy, nuclear medicine, industrial radiography, industrial gauges, industrial irradiators, and well logging. This paper includes an inventory of the sources and types of devices/equipment used by licensed users of radioactive materials in the Philippines as a contribution to the data base being prepared by the IAEA. The problems encountered by the regulatory body in the licensing and enforcement process, as well as the lessons learned from incidents involving radioactive materials are discussed. Plans for improving compliance to the regulations and enhancing the effectiveness of PNRI's regulatory functions are presented. (author)

  2. Criteria of exemption of regulatory control for radioactive material

    International Nuclear Information System (INIS)

    Marco A. Medrano Lopez

    1991-01-01

    Being based on the information contained in the 10 CFR Part 20, of the section 20.301 until the 20.306 where the mechanisms by means of which can prepare the waste of low level are indicated. While the Nuclear Regulatory Commission (NRC) it amended in the year of 1985 the Act of Politics on Low level Wastes, in particular the section 10 of the amendment of the Act, relative to the concept BRC treats those groups of radioactive waste in that their activity contents are so low that they could be exempt of the regulatory control, either liberating them toward the environment or to exempt people or organizations of the regulatory control

  3. Effective regulatory control of radioactive sources

    International Nuclear Information System (INIS)

    Meserve, R.A.

    2001-01-01

    This paper provides an overview of the situation in the USA regarding government control over use of radiation sources, the challenges it faces and the potential paths to their resolution. In the light of the large number of radiation sources in use worldwide, the safety record on balance is remarkably good. But there is still considerable room for improvement. The IAEA has an important role to play, and it is playing it effectively

  4. Dual Nature of Translational Control by Regulatory BC RNAs ▿

    Science.gov (United States)

    Eom, Taesun; Berardi, Valerio; Zhong, Jun; Risuleo, Gianfranco; Tiedge, Henri

    2011-01-01

    In higher eukaryotes, increasing evidence suggests, gene expression is to a large degree controlled by RNA. Regulatory RNAs have been implicated in the management of neuronal function and plasticity in mammalian brains. However, much of the molecular-mechanistic framework that enables neuronal regulatory RNAs to control gene expression remains poorly understood. Here, we establish molecular mechanisms that underlie the regulatory capacity of neuronal BC RNAs in the translational control of gene expression. We report that regulatory BC RNAs employ a two-pronged approach in translational control. One of two distinct repression mechanisms is mediated by C-loop motifs in BC RNA 3′ stem-loop domains. These C-loops bind to eIF4B and prevent the factor's interaction with 18S rRNA of the small ribosomal subunit. In the second mechanism, the central A-rich domains of BC RNAs target eIF4A, specifically inhibiting its RNA helicase activity. Thus, BC RNAs repress translation initiation in a bimodal mechanistic approach. As BC RNA functionality has evolved independently in rodent and primate lineages, our data suggest that BC RNA translational control was necessitated and implemented during mammalian phylogenetic development of complex neural systems. PMID:21930783

  5. Regulatory control for safe usage of radiation sources in India

    International Nuclear Information System (INIS)

    Ghosh, P.K.; Sonawane, A.U.

    1998-01-01

    The widespread applications of radioactive materials and radiation generating equipment in the field of industry, medicine agriculture and research in India necessitated the establishment of an efficient regulatory framework and consequently the Atomic Energy Regulatory Board (AERB) was constituted to exercise regulatory control over the safe usage of the radioactive materials and the radiation generating equipment. The Atomic Energy Act, 1962 and the Radiation Protection Rules, 1971 promulgated under the Act forms the basis of radiation safety in India and Chairman, AERB is the Competent Authority to enforce the regulatory provisions of the Radiation Protection Rules, 1971, for safe use of radiation source in the country. AERB has published a number of documents such as Radiation Surveillance Procedures, Standards, Codes, Guides and Manuals for safe use and handling of radioactive materials and radiation generating equipment. Apart from nuclear fuel cycle documents, these publications pertain to industrial radiography, medical application of radiation, transport of radioactive material, industrial gamma irradiators, X-ray units etc. AERB safety related publications are based on international standards e.g. BSS, IAEA, ICRP, ISO etc. This paper outlines the methodology of regulatory control exercised by AERB for safe use of the radioactive materials and the radiation generating equipment in the country. (author)

  6. A Benchmark Evaluation of Fault Tolerant Wind Turbine Control Concepts

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2015-01-01

    As the world’s power supply to a larger and larger degree depends on wind turbines, it is consequently and increasingly important that these are as reliable and available as possible. Modern fault tolerant control (FTC) could play a substantial part in increasing reliability of modern wind turbin...... accommodation is handled in software sensor and actuator blocks. This means that the wind turbine controller can continue operation as in the fault free case. The other two evaluated solutions show some potential but probably need improvements before industrial applications....

  7. Fault Tolerant Position-mooring Control for Offshore Vessels

    DEFF Research Database (Denmark)

    Blanke, Mogens; Nguyen, Trong Dong

    2018-01-01

    Fault-tolerance is crucial to maintain safety in offshore operations. The objective of this paper is to show how systematic analysis and design of fault-tolerance is conducted for a complex automation system, exemplified by thruster assisted Position-mooring. Using redundancy as required....... Functional faults that are only detectable, are rendered isolable through an active isolation approach. Once functional faults are isolated, they are handled by fault accommodation techniques to meet overall control objectives specified by class requirements. The paper illustrates the generic methodology...... by a system to handle faults in mooring lines, sensors or thrusters. Simulations and model basin experiments are carried out to validate the concept for scenarios with single or multiple faults. The results demonstrate that enhanced availability and safety are obtainable with this design approach. While...

  8. Regulatory control analysis and design for sewer systems

    DEFF Research Database (Denmark)

    Mollerup, Ane Loft; Mikkelsen, Peter Steen; Thornberg, Dines

    2015-01-01

    A systematic methodology for regulatory control analysis and design is adapted for sewer system operation and evaluated. The main challenge with adapting the methodology is the handling of the stochastic and transient nature of the rainfall disturbances, inherent to sewer system operation...

  9. The Atomic Energy Control Board's regulatory research and support program

    International Nuclear Information System (INIS)

    1988-04-01

    The purpose of the Regulatory Research and Support Program is to augment and extend the capability of the Atomic Energy Control Board's (AECB) regulatory program beyond the capability of in-house resources. The overall objective of the program is to produce pertinent and independent scientific and other knowledge and expertise that will assist the AECB in making correct, timely and credible decisions on regulating the development, application and use of atomic energy. The objectives are achieved through contracted research, development, studies, consultant and other kinds of projects administered by the Research and Radiation Protection Branch (RRB) of the AECB

  10. Regulatory dendritic cells for promotion of liver transplant operational tolerance: Rationale for a clinical trial and accompanying mechanistic studies.

    Science.gov (United States)

    Thomson, Angus W; Humar, Abhinav; Lakkis, Fadi G; Metes, Diana M

    2018-05-01

    Dendritic cells (DC) are rare, bone marrow (BM)-derived innate immune cells that critically maintain self-tolerance in the healthy steady-state. Regulatory DC (DCreg) with capacity to suppress allograft rejection and promote transplant tolerance in pre-clinical models can readily be generated from BM precursors or circulating blood monocytes. These DCreg enhance allograft survival via various mechanisms, including promotion of regulatory T cells. In non-human primates receiving minimal immunosuppressive drug therapy (IS), infusion of DCreg of donor origin, one week before transplant, safely prolongs renal allograft survival and selectively attenuates anti-donor CD8 + memory T cell responses in the early post-transplant period. Based on these observations, and in view of the critical need to reduce patient dependence on non-specific IS agents that predispose to cardiometabolic side effects and renal insufficiency, we will conduct a first-in-human safety and preliminary efficacy study of donor-derived DCreg infusion to achieve early (18 months post-transplant) complete IS withdrawal in low-risk, living donor liver transplant recipients receiving standard-of-care IS (mycophenolate mofetil, tacrolimus and steroids). We will test the hypothesis that, although donor-derived DCreg are short-lived, they will induce robust donor-specific T cell hyporesponsiveness. We will examine immunological mechanisms by sequential analysis of blood and tissue samples, incorporating cutting-edge technologies. Copyright © 2017 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  11. Competent authority regulatory control of the transport of radioactive material

    International Nuclear Information System (INIS)

    1987-04-01

    The purpose of this guide is to assist competent authorities in regulating the transport of radioactive materials and to assist users of transport regulations in their interactions with competent authorities. The guide should assist specifically those countries which are establishing their regulatory framework and further assist countries with established procedures to harmonize their application and implementation of the IAEA Regulations. This guide specifically covers various aspects of the competent authority implementation of the IAEA Regulations for the Safe Transport of Radioactive Material. In addition, physical protection and safeguards control of the transport of nuclear materials as well as third party liability aspects are briefly discussed. This is because they have to be taken into account in overall transport regulatory activities, especially when establishing the regulatory framework

  12. Fault Tolerant Control for Civil Structures Based on LMI Approach

    Directory of Open Access Journals (Sweden)

    Chunxu Qu

    2013-01-01

    Full Text Available The control system may lose the performance to suppress the structural vibration due to the faults in sensors or actuators. This paper designs the filter to perform the fault detection and isolation (FDI and then reforms the control strategy to achieve the fault tolerant control (FTC. The dynamic equation of the structure with active mass damper (AMD is first formulated. Then, an estimated system is built to transform the FDI filter design problem to the static gain optimization problem. The gain is designed to minimize the gap between the estimated system and the practical system, which can be calculated by linear matrix inequality (LMI approach. The FDI filter is finally used to isolate the sensor faults and reform the FTC strategy. The efficiency of FDI and FTC is validated by the numerical simulation of a three-story structure with AMD system with the consideration of sensor faults. The results show that the proposed FDI filter can detect the sensor faults and FTC controller can effectively tolerate the faults and suppress the structural vibration.

  13. Regulatory control of radioactivity and nuclear fuel cycle in Canada

    International Nuclear Information System (INIS)

    Hamel, P.E.; Jennekens, J.H.

    1977-05-01

    Legislation and regulations giving birth to the Atomic Energy Control Board (AECB) are outlined, as well as current licencing procedures. The AECB bases its health and safety criteria on ICRP recommendations. R and D is funded to aid regulatory activity. Licencing activities cover uranium resource management, uranium mining and milling, nuclear generating stations, heavy water plants, and radioactive waste management. Safeguards, physical security, and international controls are also concerns of the AECB. (E.C.B.)

  14. SIFT - Design and analysis of a fault-tolerant computer for aircraft control. [Software Implemented Fault Tolerant systems

    Science.gov (United States)

    Wensley, J. H.; Lamport, L.; Goldberg, J.; Green, M. W.; Levitt, K. N.; Melliar-Smith, P. M.; Shostak, R. E.; Weinstock, C. B.

    1978-01-01

    SIFT (Software Implemented Fault Tolerance) is an ultrareliable computer for critical aircraft control applications that achieves fault tolerance by the replication of tasks among processing units. The main processing units are off-the-shelf minicomputers, with standard microcomputers serving as the interface to the I/O system. Fault isolation is achieved by using a specially designed redundant bus system to interconnect the processing units. Error detection and analysis and system reconfiguration are performed by software. Iterative tasks are redundantly executed, and the results of each iteration are voted upon before being used. Thus, any single failure in a processing unit or bus can be tolerated with triplication of tasks, and subsequent failures can be tolerated after reconfiguration. Independent execution by separate processors means that the processors need only be loosely synchronized, and a novel fault-tolerant synchronization method is described.

  15. Regulatory aspects of low doses control in Albania

    International Nuclear Information System (INIS)

    Dollani, K.; Kushe, R.

    1997-01-01

    In the present paper are described the status of regulatory aspects of low doses control as well as the existing procedures for their implementation in Albania. According to new Radiological Protection Act, approved by Parliament in 1995, the establishment of the infrastructures in radiation protection area is in course, accompanied by the installation and functioning of new equipment for low dose control. Based in many years experience it is concluded that personal doses of the workers added by practices in Albania are 1/10 of dose Emits. Some particular cases of overexposured workers were investigated. Last times the elements of the optimisation procedures (QA and QC) are outlined in the frame of improving regulatory aspects of low doses control. (author)

  16. The regulatory control of ionizing radiation sources in Lithuania

    International Nuclear Information System (INIS)

    Mastauskas, A.; Ziliukas, J.; Morkunas, G.

    1998-01-01

    The Radiation Protection Centre of the Ministry of Health is the regulatory authority responsible for radiation protection of the public and of workers using sources of ionizing radiation in Lithuania. One of its responsibilities is the control of radioactive sources, which includes keeping the registry, investigating persons arrested while illegally carrying or in possession of radioactive material, decision making and control of users of radioactive sources. The computer based registry contains a directory of more than 24,000 sources and some 800 users in research, medicine and industry. Most of these sources are found in smoke detectors and X ray equipment. The potentially most dangerous sources for therapy and industry (sealed and unsealed) are also listed in this registry. Problems connected with the regulatory control of radioactive sources in Lithuania are presented and their solution is discussed. (author)

  17. Fault tolerant control based on active fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2005-01-01

    An active fault diagnosis (AFD) method will be considered in this paper in connection with a Fault Tolerant Control (FTC) architecture based on the YJBK parameterization of all stabilizing controllers. The architecture consists of a fault diagnosis (FD) part and a controller reconfiguration (CR......) part. The FTC architecture can be applied for additive faults, parametric faults, and for system structural changes. Only parametric faults will be considered in this paper. The main focus in this paper is on the use of the new approach of active fault diagnosis in connection with FTC. The active fault...... diagnosis approach is based on including an auxiliary input in the system. A fault signature matrix is introduced in connection with AFD, given as the transfer function from the auxiliary input to the residual output. This can be considered as a generalization of the passive fault diagnosis case, where...

  18. Antigen-specific tolerance inhibits autoimmune uveitis in pre-sensitized animals by deletion and CD4+CD25+ T-regulatory cells.

    Science.gov (United States)

    Matta, Bharati; Jha, Purushottam; Bora, Puran S; Bora, Nalini S

    2010-02-01

    The objective of this study was to inhibit experimental autoimmune anterior uveitis (EAAU) by establishing antigen-specific immune tolerance in animals pre-sensitized with melanin-associated antigen (MAA). Intravenous administration of MAA on days 6, 7, 8 and 9 post-immunization induced tolerance and inhibited EAAU in all Lewis rats. The number of cells (total T cells, CD4(+) T cells and CD8(+) T cells) undergoing apoptosis dramatically increased in the popliteal lymph nodes (LNs) of the tolerized animals compared with non-tolerized animals. In addition, Fas ligand (FasL), TNF receptor 1 (TNFR1) and caspase-8 were upregulated in tolerized rats. Proliferation of total lymphocytes, CD4(+)T cells and CD8(+) T cells (harvested from the popliteal LNs) in response to antigenic stimulation was drastically reduced in the state of tolerance compared with the cells from non-tolerized animals. The level of interferon (IFN)-gamma and IL-2 decreased, whereas TGF-beta2 was elevated in the state of tolerance. Furthermore, the number of CD4(+)CD25(+)FoxP3(+) regulatory T cells (Tregs) increased in the popliteal LNs of tolerized animals compared with non-tolerized animals. In conclusion, our results suggest that deletion of antigen-specific T cells by apoptosis and active suppression mediated by Tregs has an important role in the induction of antigen specific immune tolerance in animals with an established immune response against MAA.

  19. Generation of American elm trees with tolerance to Dutch elm disease through controlled crosses and selection

    Science.gov (United States)

    James M. Slavicek; Kathleen S. Knight

    2012-01-01

    The goal of our research and development efforts is to generate new and/or improved selections of the American elm (Ulmus americana L.) with tolerance/resistance to Dutch elm disease (DED). The approaches we are taking for this effort include: 1) controlled breeding using known DED -tolerant selections, 2) controlled breeding using DED-tolerant...

  20. Drought response in wheat: key genes and regulatory mechanisms controlling root system architecture and transpiration efficiency

    Science.gov (United States)

    Kulkarni, Manoj; Soolanayakanahally, Raju; Ogawa, Satoshi; Uga, Yusaku; Selvaraj, Michael G.; Kagale, Sateesh

    2017-12-01

    Abiotic stresses such as drought, heat, salinity and flooding threaten global food security. Crop genetic improvement with increased resilience to abiotic stresses is a critical component of crop breeding strategies. Wheat is an important cereal crop and a staple food source globally. Enhanced drought tolerance in wheat is critical for sustainable food production and global food security. Recent advances in drought tolerance research have uncovered many key genes and transcription regulators governing morpho-physiological traits. Genes controlling root architecture and stomatal development play an important role in soil moisture extraction and its retention, and therefore have been targets of molecular breeding strategies for improving drought tolerance. In this systematic review, we have summarized evidence of beneficial contributions of root and stomatal traits to plant adaptation to drought stress. Specifically, we discuss a few key genes such as DRO1 in rice and ERECTA in Arabidopsis and rice that were identified to be the enhancers of drought tolerance via regulation of root traits and transpiration efficiency. Additionally, we highlight several transcription factor families, such as ERF (ethylene response factors), DREB (dehydration responsive element binding), ZFP (zinc finger proteins), WRKY and MYB that were identified to be both positive and negative regulators of drought responses in wheat, rice, maize and/or Arabidopsis. The overall aim of this review was to provide an overview of candidate genes that have been tested as regulators of drought response in plants. The lack of a reference genome sequence for wheat and nontransgenic approaches for manipulation of gene functions in the past had impeded high-resolution interrogation of functional elements, including genes and QTLs, and their application in cultivar improvement. The recent developments in wheat genomics and reverse genetics, including the availability of a gold-standard reference genome

  1. Fault tolerant vector control of induction motor drive

    International Nuclear Information System (INIS)

    Odnokopylov, G; Bragin, A

    2014-01-01

    For electric composed of technical objects hazardous industries, such as nuclear, military, chemical, etc. an urgent task is to increase their resiliency and survivability. The construction principle of vector control system fault-tolerant asynchronous electric. Displaying recovery efficiency three-phase induction motor drive in emergency mode using two-phase vector control system. The process of formation of a simulation model of the asynchronous electric unbalance in emergency mode. When modeling used coordinate transformation, providing emergency operation electric unbalance work. The results of modeling transient phase loss motor stator. During a power failure phase induction motor cannot save circular rotating field in the air gap of the motor and ensure the restoration of its efficiency at rated torque and speed

  2. Alloreactive regulatory T cells allow the generation of mixed chimerism and transplant tolerance

    Directory of Open Access Journals (Sweden)

    Paulina eRuiz

    2015-11-01

    Full Text Available The induction of donor-specific transplant tolerance is one of the main goals of modern immunology. Establishment of a mixed chimerism state in the transplant recipient has proven to be a suitable strategy for the induction of long-term allograft tolerance; however, current experimental recipient preconditioning protocols have many side effects, and are not feasible for use in future therapies. In order to improve the current mixed chimerism induction protocols, we developed a non-myeloablative bone-marrow transplant protocol using retinoic acid induced alloantigen-specific Tregs, clinically available immunosuppressive drugs and lower doses of irradiation. We demonstrate that retinoic acid induced alloantigen-specific Tregs in addition to a non-myeloablative bone-marrow transplant protocol generates stable mixed chimerism and induce tolerance to allogeneic secondary skin allografts in mice. Therefore, the establishment of mixed chimerism through the use of donor-specific Tregs rather than non-specific immunosuppression could have a potential use in organ transplantation.

  3. Controllability analysis of transcriptional regulatory networks reveals circular control patterns among transcription factors

    DEFF Research Database (Denmark)

    Österlund, Tobias; Bordel, Sergio; Nielsen, Jens

    2015-01-01

    % for the human network. The high controllability (low number of drivers needed to control the system) in yeast, mouse and human is due to the presence of internal loops in their regulatory networks where the TFs regulate each other in a circular fashion. We refer to these internal loops as circular control...... motifs (CCM). The E. coli transcriptional regulatory network, which does not have any CCMs, shows a hierarchical structure of the transcriptional regulatory network in contrast to the eukaryal networks. The presence of CCMs also has influence on the stability of these networks, as the presence of cycles...

  4. Regulatory control of radiation sources in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Daroy, Rosita R

    1996-12-31

    This paper is concerned with the radiation protection and safety infrastructure providing emphasis on the regulation and control of radiation sources in the Philippines. It deals with the experiences of the Philippine Nuclear Research Institute, as a regulatory body, in the regulation and control of radioactive materials in radiotherapy, nuclear medicine, industrial radiography, industrial gauges, industrial irradiators, and well logging. This paper includes an inventory of the sources and types of devices/equipment used by licensed users of radioactive materials in the Philippines as a contribution to the data base being prepared by the IAEA. The problems encountered by the regulatory body in the licensing and enforcement process, as well as the lessons learned from incidents involving radioactive materials are discussed. Plans for improving compliance to the regulations and enhancing the effectiveness of PNRI`s regulatory functions are presented. (author). Paper presented during the IAEA Regional (RCA) Workshop on System of Notification, Registration, Licensing, and Control of Radiation Sources and Installations, Jakarta, Indonesia, 24-28 April 1995. 6 refs., 2 figs., 12 tabs.

  5. Regulatory Framework for Controlling the Research Reactor Decommissioning Project

    International Nuclear Information System (INIS)

    Melani, Ai; Chang, Soon Heung

    2009-01-01

    Decommissioning is one of important stages in construction and operation of research reactors. Currently, there are three research reactors operating in Indonesia. These reactors are operated by the National Nuclear Energy Agency (BATAN). The age of the three research reactors varies from 22 to 45 years since the reactors reached their first criticality. Regulatory control of the three reactors is conducted by the Nuclear Energy Regulatory Agency (BAPETEN). Controlling the reactors is carried out based on the Act No. 10/1997 on Nuclear Energy, Government Regulations and BAPETEN Chairman Decrees concerning the nuclear safety, security and safeguards. Nevertheless, BAPETEN still lack of the regulation, especially for controlling the decommissioning project. Therefore, in the near future BAPETEN has to prepare the regulations for decommissioning, particularly to anticipate the decommissioning of the oldest research reactors, which probably will be done in the next ten years. In this papers author give a list of regulations should be prepared by BAPETEN for the decommissioning stage of research reactor in Indonesia based on the international regulatory practice

  6. Regulatory Mechanisms Controlling Maturation of Serotonin Neuron Identity and Function.

    Science.gov (United States)

    Spencer, William C; Deneris, Evan S

    2017-01-01

    The brain serotonin (5-hydroxytryptamine; 5-HT) system has been extensively studied for its role in normal physiology and behavior, as well as, neuropsychiatric disorders. The broad influence of 5-HT on brain function, is in part due to the vast connectivity pattern of 5-HT-producing neurons throughout the CNS. 5-HT neurons are born and terminally specified midway through embryogenesis, then enter a protracted period of maturation, where they functionally integrate into CNS circuitry and then are maintained throughout life. The transcriptional regulatory networks controlling progenitor cell generation and terminal specification of 5-HT neurons are relatively well-understood, yet the factors controlling 5-HT neuron maturation are only recently coming to light. In this review, we first provide an update on the regulatory network controlling 5-HT neuron development, then delve deeper into the properties and regulatory strategies governing 5-HT neuron maturation. In particular, we discuss the role of the 5-HT neuron terminal selector transcription factor (TF) Pet-1 as a key regulator of 5-HT neuron maturation. Pet-1 was originally shown to positively regulate genes needed for 5-HT synthesis, reuptake and vesicular transport, hence 5-HT neuron-type transmitter identity. It has now been shown to regulate, both positively and negatively, many other categories of genes in 5-HT neurons including ion channels, GPCRs, transporters, neuropeptides, and other transcription factors. Its function as a terminal selector results in the maturation of 5-HT neuron excitability, firing characteristics, and synaptic modulation by several neurotransmitters. Furthermore, there is a temporal requirement for Pet-1 in the control of postmitotic gene expression trajectories thus indicating a direct role in 5-HT neuron maturation. Proper regulation of the maturation of cellular identity is critical for normal neuronal functioning and perturbations in the gene regulatory networks controlling

  7. Regulatory systems for the control of land remediation processes

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, J.; Vijgen, J.; Summersgill, M.

    2003-07-01

    One of the recurring themes in looking at land remediation over the last decade has been identifying and overcoming barriers to the use of innovative, sustainable technologies, whilst still ensuring that there are no adverse environmental impacts from their use. In parallel with this, the regeneration of brownfield sites has increasingly needed effective and economic solutions that leave the site without the stigma of being associated with contamination and waste disposal. Regulatory controls are often identified as one of the main barriers to both of these objectives. Previously, the focus of attention in the study of regulatory controls relating to land contamination has largely been on regimes that trigger the need for clean-up. These may be pollution control legislation or land-use planning controls. However, the focus of this paper will be on the controls on the selection and implementation of the remediation technologies and processes themselves. It will look in particular at the European-wide controls on waste management, pollution prevention and environmental impact assessment. The UK work is being carried out by a working group involving: landowners; developers; public sector regeneration agencies; house-builders; industry; insurers; technology providers; professional advisers; local government authorities; and national government regulators and policy-makers. This multi-stakeholder approach has facilitated the identification of practical, legal, financial and administrative issues to assist in developing new solutions. (orig.)

  8. Parameter Estimation Analysis for Hybrid Adaptive Fault Tolerant Control

    Science.gov (United States)

    Eshak, Peter B.

    Research efforts have increased in recent years toward the development of intelligent fault tolerant control laws, which are capable of helping the pilot to safely maintain aircraft control at post failure conditions. Researchers at West Virginia University (WVU) have been actively involved in the development of fault tolerant adaptive control laws in all three major categories: direct, indirect, and hybrid. The first implemented design to provide adaptation was a direct adaptive controller, which used artificial neural networks to generate augmentation commands in order to reduce the modeling error. Indirect adaptive laws were implemented in another controller, which utilized online PID to estimate and update the controller parameter. Finally, a new controller design was introduced, which integrated both direct and indirect control laws. This controller is known as hybrid adaptive controller. This last control design outperformed the two earlier designs in terms of less NNs effort and better tracking quality. The performance of online PID has an important role in the quality of the hybrid controller; therefore, the quality of the estimation will be of a great importance. Unfortunately, PID is not perfect and the online estimation process has some inherited issues; the online PID estimates are primarily affected by delays and biases. In order to ensure updating reliable estimates to the controller, the estimator consumes some time to converge. Moreover, the estimator will often converge to a biased value. This thesis conducts a sensitivity analysis for the estimation issues, delay and bias, and their effect on the tracking quality. In addition, the performance of the hybrid controller as compared to direct adaptive controller is explored. In order to serve this purpose, a simulation environment in MATLAB/SIMULINK has been created. The simulation environment is customized to provide the user with the flexibility to add different combinations of biases and delays to

  9. Active Disturbance Rejection Approach for Robust Fault-Tolerant Control via Observer Assisted Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    John Cortés-Romero

    2013-01-01

    Full Text Available This work proposes an active disturbance rejection approach for the establishment of a sliding mode control strategy in fault-tolerant operations. The core of the proposed active disturbance rejection assistance is a Generalized Proportional Integral (GPI observer which is in charge of the active estimation of lumped nonlinear endogenous and exogenous disturbance inputs related to the creation of local sliding regimes with limited control authority. Possibilities are explored for the GPI observer assisted sliding mode control in fault-tolerant schemes. Convincing improvements are presented with respect to classical sliding mode control strategies. As a collateral advantage, the observer-based control architecture offers the possibility of chattering reduction given that a significant part of the control signal is of the continuous type. The case study considers a classical DC motor control affected by actuator faults, parametric failures, and perturbations. Experimental results and comparisons with other established sliding mode controller design methodologies, which validate the proposed approach, are provided.

  10. Strengthening the regulatory control of consumer goods through international harmonization

    International Nuclear Information System (INIS)

    Yus Rusdian Akhmad

    2013-01-01

    The International Atomic Energy Agency (IAEA) is currently working on a recommendation in the form of guidelines for regulating consumer goods. Preparation of this document has a significant dimension of international issues, especially in terms of the application of the principles of justification and application of the concept of exemption. International harmonization among regulators ranging from the regional to the global level is a central issue and considering the complex issues that arise in addition to covering the scientific aspects also involve consideration of the legal aspects or values espoused by any State which may differ from one another. PERKA BAPETEN on consumer goods is still in the preparation stage so that the discussion of the material will be useful for improving the quality of the regulation in time. There is a significant gap of understanding to the related materials by the parties concerned (between local and international parties were among the local party). This paper intends to propose the understanding and views on radiation protection and regulatory control for consumer goods and hopely could contributed significantly to strengthening its regulatory control which is primarily through a reduction in the gap of understanding to the related concept that potentially multi perceptions and encourage stronger cooperation among regulatory bodies. (author)

  11. Control of radioactive sources in industry through regulatory inspections

    International Nuclear Information System (INIS)

    Leocadio, J.C.; Ramalho, A.T.; Pinho, A.S.; Lourenco, M.M.J.; Nicola, M.S.; D'Avila, R.L.; Melo, I.F.; Cucco, A.C.S.

    2005-01-01

    In Brazil, the applications of ionizing radiation in industry are accomplished about 900 radioactive facilities, which handle approximately 3.000 radiation sources. The control of radioactive sources used in industrial installations authorized by the Brazilian Nuclear Energy Commission (CNEN) is accomplished by Servico de Radioprotecao na Industria Radiativa (SERIR) of the Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ, Brazil. This service carries out regulatory inspections in the practices of industrial radiography, nuclear gauges, industrial irradiators and oil wells logging. The frequency of inspections depends on the type of practice, ranging from a year to 5 years, depending on the risk involved. This paper presents a brief description of the situation of radiation safety in the use of radioactive sources in the industries of the country. The results obtained with regulatory inspections at industrial installations demonstrate that the conditions of safety and radiation protection in these facilities are satisfactory when compared with the technical regulations, both national and international

  12. Fault tolerant control of multivariable processes using auto-tuning PID controller.

    Science.gov (United States)

    Yu, Ding-Li; Chang, T K; Yu, Ding-Wen

    2005-02-01

    Fault tolerant control of dynamic processes is investigated in this paper using an auto-tuning PID controller. A fault tolerant control scheme is proposed composing an auto-tuning PID controller based on an adaptive neural network model. The model is trained online using the extended Kalman filter (EKF) algorithm to learn system post-fault dynamics. Based on this model, the PID controller adjusts its parameters to compensate the effects of the faults, so that the control performance is recovered from degradation. The auto-tuning algorithm for the PID controller is derived with the Lyapunov method and therefore, the model predicted tracking error is guaranteed to converge asymptotically. The method is applied to a simulated two-input two-output continuous stirred tank reactor (CSTR) with various faults, which demonstrate the applicability of the developed scheme to industrial processes.

  13. Guaranteed Cost Fault-Tolerant Control for Networked Control Systems with Sensor Faults

    Directory of Open Access Journals (Sweden)

    Qixin Zhu

    2015-01-01

    Full Text Available For the large scale and complicated structure of networked control systems, time-varying sensor faults could inevitably occur when the system works in a poor environment. Guaranteed cost fault-tolerant controller for the new networked control systems with time-varying sensor faults is designed in this paper. Based on time delay of the network transmission environment, the networked control systems with sensor faults are modeled as a discrete-time system with uncertain parameters. And the model of networked control systems is related to the boundary values of the sensor faults. Moreover, using Lyapunov stability theory and linear matrix inequalities (LMI approach, the guaranteed cost fault-tolerant controller is verified to render such networked control systems asymptotically stable. Finally, simulations are included to demonstrate the theoretical results.

  14. Regulatory control of nuclear safety in Finland. Annual report 2008

    International Nuclear Information System (INIS)

    Kainulainen, E.

    2009-06-01

    This report covers the regulatory control of nuclear safety in 2008, including the design, construction and operation of nuclear facilities, as well as nuclear waste management and nuclear materials. The control of nuclear facilities and nuclear waste management, as well as nuclear non-proliferation, concern two STUK departments: Nuclear Reactor Regulation and Nuclear Waste and Material Regulation. It constitutes the report on regulatory control in the field of nuclear energy, which the Radiation and Nuclear Safety Authority (STUK) is required to submit to the Ministry of Employment and the Economy pursuant to section 121 of the Finnish Nuclear Energy Decree. The first parts of the report explain the basics of the nuclear safety regulation included as part of STUK's responsibilities, as well as the objectives of the operations, and briefly introduce the objects of regulation. The chapter concerning the development and implementation of legislation and regulations describes changes in nuclear legislation, as well as the progress of STUK's YVL Guide revision. The chapter also includes a summary of the application of the updated YVL Guides to nuclear facilities. The section concerning the regulation of nuclear facilities contains a complete safety assessment of the nuclear facilities currently in operation or under construction. For the nuclear facilities in operation, the section describes plant operation, events during operation, annual maintenance, development of the plants and their safety, and observations made during monitoring. Data and observations gained during regulatory activities are reviewed with a focus on ensuring the safety functions of nuclear facilities and the integrity of structures and components. The report also includes a description of the oversight of the operations and quality management of organisations, oversight of operational experience feedback activities, and the results of these oversight activities. The radiation safety of nuclear

  15. An early response regulatory cluster induced by low temperature and hydrogen peroxide in seedlings of chilling-tolerant japonica rice

    Directory of Open Access Journals (Sweden)

    Jia Yulin

    2007-06-01

    Full Text Available Abstract Background Plants respond to low temperature through an intricately coordinated transcriptional network. The CBF/DREB-regulated network of genes has been shown to play a prominent role in freeze-tolerance of Arabidopsis through the process of cold acclimation (CA. Recent evidence also showed that the CBF/DREB regulon is not unique to CA but evolutionarily conserved between chilling-insensitive (temperate and chilling-sensitive (warm-season plants. In this study, the wide contrast in chilling sensitivity between indica and japonica rice was used as model to identify other regulatory clusters by integrative analysis of promoter architecture (ab initio and gene expression profiles. Results Transcriptome analysis in chilling tolerant japonica rice identified a subset of 121 'early response' genes that were upregulated during the initial 24 hours at 10°C. Among this group were four transcription factors including ROS-bZIP1 and another larger sub-group with a common feature of having as1/ocs-like elements in their promoters. Cold-induction of ROS-bZIP1 preceded the induction of as1/ocs-like element-containing genes and they were also induced by exogenous H2O2 at ambient temperature. Coordinated expression patterns and similar promoter architectures among the 'early response' genes suggest that they belong to a potential regulon (ROS-bZIP – as1/ocs regulatory module that responds to elevated levels of ROS during chilling stress. Cultivar-specific expression signatures of the candidate genes indicate a positive correlation between the activity of the putative regulon and genotypic variation in chilling tolerance. Conclusion A hypothetical model of an ROS-mediated regulon (ROS-bZIP – as1/ocs triggered by chilling stress was assembled in rice. Based on the current results, it appears that this regulon is independent of ABA and CBF/DREB, and that its activation has an important contribution in configuring the rapid responses of rice seedlings

  16. Regulatory control of nuclear safety in Finland. Annual report 1997

    International Nuclear Information System (INIS)

    Tossavainen, K.

    1998-08-01

    The report describes regulatory control of the use of nuclear energy by the Radiation and Nuclear Safety Authority (STUK) in Finland in 1997. Nuclear regulatory control ascertained that the operation of Finnish NPPs was in compliance with the conditions set out in operating licences and current regulations. In addition to NPP normal operation, STUK oversaw projects at the plant units relating to power uprating and safety improvements. STUK prepared statements for the Ministry of Trade and Industry about the applications for renewing the operating licenses of Loviisa and Olkiluoto NPPs. The most important items of supervision in nuclear waste management were studies relating to the final disposal of spent fuel from NPPs and the review of the licence application for a repository for low- and intermediate-level reactor waste from Loviisa NPP. Preparation of general safety regulations for the final disposal of spent nuclear fuel, to be published in the form of a Council of State Decision, was started. By safeguards control, the use of nuclear materials was verified to be in compliance with current regulations and that the whereabouts of every batch of nuclear material were always known. Nuclear material safeguards were stepped up to prevent illicit trafficking of nuclear materials and other radioactive materials. In co-operation with the Ministry for Foreign Affairs and the Institute of Seismology (University of Helsinki), preparations were undertaken to implement the Comprehensive Nuclear Test Ban Treaty (CTBT). For enforcement of the Treaty and as part of the international regulatory approach, STUK is currently developing laboratory analyses relating to airborne radioactivity measurements. The focus of co-operation funded by external sources was as follows: improvement of the safety of Kola and Leningrad NPPs, improvement of nuclear waste management in North-West Russia, development of the organizations of nuclear safety authorities in Eastern Europe and development

  17. Novel neural networks-based fault tolerant control scheme with fault alarm.

    Science.gov (United States)

    Shen, Qikun; Jiang, Bin; Shi, Peng; Lim, Cheng-Chew

    2014-11-01

    In this paper, the problem of adaptive active fault-tolerant control for a class of nonlinear systems with unknown actuator fault is investigated. The actuator fault is assumed to have no traditional affine appearance of the system state variables and control input. The useful property of the basis function of the radial basis function neural network (NN), which will be used in the design of the fault tolerant controller, is explored. Based on the analysis of the design of normal and passive fault tolerant controllers, by using the implicit function theorem, a novel NN-based active fault-tolerant control scheme with fault alarm is proposed. Comparing with results in the literature, the fault-tolerant control scheme can minimize the time delay between fault occurrence and accommodation that is called the time delay due to fault diagnosis, and reduce the adverse effect on system performance. In addition, the FTC scheme has the advantages of a passive fault-tolerant control scheme as well as the traditional active fault-tolerant control scheme's properties. Furthermore, the fault-tolerant control scheme requires no additional fault detection and isolation model which is necessary in the traditional active fault-tolerant control scheme. Finally, simulation results are presented to demonstrate the efficiency of the developed techniques.

  18. Regulatory control of nuclear safety in Finland. Annual report 1998

    Energy Technology Data Exchange (ETDEWEB)

    Tossavainen, K. [ed.

    1999-10-01

    The report describes regulatory control of the safe use of nuclear energy by the Radiation and Nuclear Safety Authority (STUK) in 1998. STUK is the Finnish nuclear safety authority. The submission of this report to the Ministry of Trade and Industry is stipulated in Section 121 of the Nuclear Energy Decree. It was verified by regulatory control that the operation of Finnish NPPs was in compliance with conditions set out in the operating licences of the plants and with regulations currently in force. In addition to supervising the normal operation of the plants, STUK oversaw projects carried out at the plant units, which related to the uprating of their power and the improvement of their safety. STUK issued to the Ministry of Trade and Industry a statement about applications for the renewal of the operating licences of Loviisa and Olkiluoto NPPs, which had been submitted by Imatran Voima Oy and Teollisuuden Voima Oy. Regulatory activities in the field of nuclear waste management were focused on the storage and final disposal of spent fuel as well as the treatment, storage and final disposal of reactor waste. STUK issued a statement to the Ministry of Trade and Industry about an environmental impact assessment programme pertaining to a spent fuel repository project, which had been submitted by Posiva Oy, as well as on Imatran Voima Oy's application concerning the operation of a repository for medium- and low-level reactor waste from Loviisa NPP. The use of nuclear materials was in compliance with the regulations currently in force and also the whereabouts of every batch of nuclear material were ensured by safeguards control. In international safeguards, important changes took place, which were reflected also in safeguards activities at national level. International co-operation continued based on financing both from STUK's budget and from additional sources. The focus of co-operation funded from outside sources was as follows: improvement of the safety of

  19. Regulatory control of nuclear safety in Finland. Annual report 1998

    International Nuclear Information System (INIS)

    Tossavainen, K.

    1999-10-01

    The report describes regulatory control of the safe use of nuclear energy by the Radiation and Nuclear Safety Authority (STUK) in 1998. STUK is the Finnish nuclear safety authority. The submission of this report to the Ministry of Trade and Industry is stipulated in Section 121 of the Nuclear Energy Decree. It was verified by regulatory control that the operation of Finnish NPPs was in compliance with conditions set out in the operating licences of the plants and with regulations currently in force. In addition to supervising the normal operation of the plants, STUK oversaw projects carried out at the plant units, which related to the uprating of their power and the improvement of their safety. STUK issued to the Ministry of Trade and Industry a statement about applications for the renewal of the operating licences of Loviisa and Olkiluoto NPPs, which had been submitted by Imatran Voima Oy and Teollisuuden Voima Oy. Regulatory activities in the field of nuclear waste management were focused on the storage and final disposal of spent fuel as well as the treatment, storage and final disposal of reactor waste. STUK issued a statement to the Ministry of Trade and Industry about an environmental impact assessment programme pertaining to a spent fuel repository project, which had been submitted by Posiva Oy, as well as on Imatran Voima Oy's application concerning the operation of a repository for medium- and low-level reactor waste from Loviisa NPP. The use of nuclear materials was in compliance with the regulations currently in force and also the whereabouts of every batch of nuclear material were ensured by safeguards control. In international safeguards, important changes took place, which were reflected also in safeguards activities at national level. International co-operation continued based on financing both from STUK's budget and from additional sources. The focus of co-operation funded from outside sources was as follows: improvement of the safety of Kola and

  20. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (T FH ) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of T FH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on T FH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate T FH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing T FH cell maturation. In cocultures they differentiated B cells into CD138 + plasma and IgD - CD27 + memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented T FH cell development. Added to T FH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3 + CXCR5 + PD-1 + follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on T FH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control T FH cell maturation, expand follicular regulatory T cells, and inhibit the T FH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the T FH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  1. Control of Metastatic Progression by microRNA Regulatory Networks

    Science.gov (United States)

    Pencheva, Nora; Tavazoie, Sohail F.

    2015-01-01

    Aberrant microRNA (miRNA) expression is a defining feature of human malignancy. Specific miRNAs have been identified as promoters or suppressors of metastatic progression. These miRNAs control metastasis through divergent or convergent regulation of metastatic gene pathways. Some miRNA regulatory networks govern cell-autonomous cancer phenotypes, while others modulate the cell-extrinsic composition of the metastatic microenvironment. The use of small RNAs as probes into the molecular and cellular underpinnings of metastasis holds promise for the identification of candidate genes for potential therapeutic intervention. PMID:23728460

  2. Regulatory control of nuclear facility valves and their actuators

    International Nuclear Information System (INIS)

    1993-01-01

    The methods and procedures by which the Finnish Centre for Radiation and Nuclear Safety (STUK) regulates valves and their actuators in nuclear power plants and in other nuclear facilities are specified in the guide. The scope of regulation depends on the Safety Class of the valve and the actuator in question. The Safety Classification principles for the systems, structures and components of the nuclear power plants are described in the guide YVL 2.1 and the regulatory control of the nuclear facility safety valves is described in the guide YVL 5.4

  3. Use and regulatory control of dental X-ray installations

    International Nuclear Information System (INIS)

    1999-01-01

    In the guide the safety requirements concerning dental X-ray installations and their use, prerequisities for exemption from a safety licence, and regulatory control are presented. The guide applies to conventional dental X-ray installations, by which an image is created on an X-ray film or other image receptor placed inside the mouth, and panorama tomography installations for dentition and the cephalostats associated with these. The guide does not apply to multitechnique tomography installations intended for the special imaging of the skull or jaws

  4. Commensal Lactobacillus Controls Immune Tolerance during Acute Liver Injury in Mice

    Directory of Open Access Journals (Sweden)

    Nobuhiro Nakamoto

    2017-10-01

    Full Text Available Summary: Gut-derived microbial antigens trigger the innate immune system during acute liver injury. During recovery, regulatory immunity plays a role in suppressing inflammation; however, the precise mechanism underlying this process remains obscure. Here, we find that recruitment of immune-regulatory classical dendritic cells (cDCs is crucial for liver tolerance in concanavalin A-induced acute liver injury. Acute liver injury resulted in enrichment of commensal Lactobacillus in the gut. Notably, Lactobacillus activated IL-22 production by gut innate lymphoid cells and raised systemic IL-22 levels. Gut-derived IL-22 enhanced mucosal barrier function and promoted the recruitment of regulatory cDCs to the liver. These cDCs produced IL-10 and TGF-β through TLR9 activation, preventing further liver inflammation. Collectively, our results indicate that beneficial gut microbes influence tolerogenic immune responses in the liver. Therefore, modulation of the gut microbiota might be a potential option to regulate liver tolerance. : Nakamoto et.al. find that Lactobacillus accumulates in the gut and activates IL-22 production by innate lymphoid cells during acute liver injury. Gut-derived IL-22 contributes to liver tolerance via induction of regulatory DCs. Keywords: immune tolerance, dendritic cell, innate lymphoid cell, acute liver injury, interleukin-10, interleukin-22, microbiota, dysbiosis

  5. Regulatory control of low level radiation exposure in Tanzania

    International Nuclear Information System (INIS)

    Nyanda, A.M.; Muhogora, W.E.

    1997-01-01

    In Tanzania, the radiation protection law was issued in 1983. Under this law, the National Radiation Commission is responsible for safe uses of ionizing radiation. The regulatory control of the resulting doses from the uses of radiation sources in medicine, industry, research and teaching is presented. The system of control reflects the existing interactions between the National Radiation Commission and users through the established radiation protection infrastructure. From the national dose registry data, it is found that the highest annual individual doses over 10 years ago, came from less than 5% of total monitored workers and were in the range 10 - 15 mSv y -1 . The experienced radiation levels in uncontrolled areas of potential workplaces is less than 1 μSv h -1 . The possibility for associating such low dose levels to the effectiveness of the existing regulatory dose control framework is discussed. Despite of this achievement, the need to improve further the radiation protection and safety programs is found necessary. (author)

  6. Plant Tolerance: A Unique Approach to Control Hemipteran Pests.

    Science.gov (United States)

    Koch, Kyle G; Chapman, Kaitlin; Louis, Joe; Heng-Moss, Tiffany; Sarath, Gautam

    2016-01-01

    Plant tolerance to insect pests has been indicated to be a unique category of resistance, however, very little information is available on the mechanism of tolerance against insect pests. Tolerance is distinctive in terms of the plant's ability to withstand or recover from herbivore injury through growth and compensatory physiological processes. Because plant tolerance involves plant compensatory characteristics, the plant is able to harbor large numbers of herbivores without interfering with the insect pest's physiology or behavior. Some studies have observed that tolerant plants can compensate photosynthetically by avoiding feedback inhibition and impaired electron flow through photosystem II that occurs as a result of insect feeding. Similarly, the up-regulation of peroxidases and other oxidative enzymes during insect feeding, in conjunction with elevated levels of phytohormones can play an important role in providing plant tolerance to insect pests. Hemipteran insects comprise some of the most economically important plant pests (e.g., aphids, whiteflies), due to their ability to achieve high population growth and their potential to transmit plant viruses. In this review, results from studies on plant tolerance to hemipterans are summarized, and potential models to understand tolerance are presented.

  7. Orchestration of transplantation tolerance by regulatory dendritic cell therapy or in situ targeting of dendritic cells

    Science.gov (United States)

    Morelli, Adrian E.; Thomson, Angus W.

    2014-01-01

    Purpose of review Extensive research in murine transplant models over the past two decades has convincingly demonstrated the ability of regulatory dendritic cells (DCreg) to promote long-term allograft survival. We review important considerations regarding the source of therapeutic DCreg (donor or recipient) and their mode of action, in situ targeting of DCreg, and optimal therapeutic regimens to promote DCreg function. Recent findings Recent studies have defined protocols and mechanisms whereby ex vivo-generated DCreg of donor or recipient origin subvert allogeneic T cell responses and promote long-term organ transplant survival. Particular interest has focused on how donor antigen (Ag) is acquired, processed and presented by autologous DCs, on the stability of DCreg, and on in situ targeting of DC to promote their tolerogenic function. New evidence of the therapeutic efficacy of DCreg in a clinically-relevant non-human primate organ transplant model and production of clinical grade DCreg support early evaluation of DCreg therapy in human graft recipients. Summary We discuss strategies currently used to promote DC tolerogenicity, including DCreg therapy and in situ targeting of DC, with a view to improved understanding of underlying mechanisms and identification of the most promising strategies for therapeutic application. PMID:24926700

  8. Regulatory Strategy to Control Radon Exposure in Pakistan

    International Nuclear Information System (INIS)

    Younus, Irfan; Cho, Kun Woo

    2012-01-01

    Pakistan Nuclear Regulatory Authority (PNRA) was established in 2001 with one of the objectives to ensure the protection of workers, general public and the environment from the harmful effects of naturally occurring and artificially produced ionizing radiations by formulating and implementing the effective regulations. Radon is a naturally occurring odorless, colorless, tasteless, imperceptible to senses and chemically inert radioactive gas which is produced continuously from the natural decay of U-238, U-235 and Th-232 in most soils, rocks and water all over the earth. High levels of radon in the soil and rock are primarily responsible for indoor radon problems. Therefore when inhaled with air, there much probability that radon decay products will stay and decay in the lungs. If stayed in the lungs, the radiation may damage the cells causing lung cancer. Hence the radon problems have been taken seriously in most of the developed countries of the world. Radon reference levels for dwellings and workplaces have been set and the general public has been made alert of radon through newspapers and electronic media. In Pakistan, neither publicity campaign nor radon measurement and control programmes have been started countrywide. Rather small individual efforts for the sake of interest have been done to investigate the radon in some specific area or institution. This paper presents the regulatory strategy to control radon exposure for the sake of radiation protection of public and workers in Pakistan

  9. Oral dendritic cells mediate antigen-specific tolerance by stimulating TH1 and regulatory CD4+ T cells.

    Science.gov (United States)

    Mascarell, Laurent; Lombardi, Vincent; Louise, Anne; Saint-Lu, Nathalie; Chabre, Henri; Moussu, Hélène; Betbeder, Didier; Balazuc, Anne-Marie; Van Overtvelt, Laurence; Moingeon, Philippe

    2008-09-01

    A detailed characterization of oral antigen-presenting cells is critical to improve second-generation sublingual allergy vaccines. To characterize oral dendritic cells (DCs) within lingual and buccal tissues from BALB/c mice with respect to their surface phenotype, distribution, and capacity to polarize CD4(+) T-cell responses. In situ analysis of oral DCs was performed by immunohistology. Purified DCs were tested in vitro for their capacity to capture, process, and present the ovalbumin antigen to naive CD4(+) T cells. In vivo priming of ovalbumin-specific T cells adoptively transferred to BALB/c mice was analyzed by cytofluorometry in cervical lymph nodes after sublingual administration of mucoadhesive ovalbumin. Three subsets of oral DCs with a distinct tissue distribution were identified: (1) a minor subset of CD207(+) Langerhans cells located in the mucosa itself, (2) a major subpopulation of CD11b(+)CD11c(-) and CD11b(+)CD11c(+) myeloid DCs at the mucosal/submucosal interface, and (3) B220(+)120G8(+) plasmacytoid DCs found in submucosal tissues. Purified myeloid and plasmacytoid oral DCs capture and process the antigen efficiently and are programmed to elicit IFN-gamma and/or IL-10 production together with a suppressive function in naive CD4(+) T cells. Targeting the ovalbumin antigen to oral DCs in vivo by using mucoadhesive particles establishes tolerance in the absence of cell depletion through the stimulation of IFN-gamma and IL-10-producing CD4(+) regulatory T cells in cervical lymph nodes. The oral immune system is composed of various subsets of tolerogenic DCs organized in a compartmentalized manner and programmed to induce T(H)1/regulatory T-cell responses.

  10. Fault detection and fault-tolerant control for nonlinear systems

    CERN Document Server

    Li, Linlin

    2016-01-01

    Linlin Li addresses the analysis and design issues of observer-based FD and FTC for nonlinear systems. The author analyses the existence conditions for the nonlinear observer-based FD systems to gain a deeper insight into the construction of FD systems. Aided by the T-S fuzzy technique, she recommends different design schemes, among them the L_inf/L_2 type of FD systems. The derived FD and FTC approaches are verified by two benchmark processes. Contents Overview of FD and FTC Technology Configuration of Nonlinear Observer-Based FD Systems Design of L2 nonlinear Observer-Based FD Systems Design of Weighted Fuzzy Observer-Based FD Systems FTC Configurations for Nonlinear Systems< Application to Benchmark Processes Target Groups Researchers and students in the field of engineering with a focus on fault diagnosis and fault-tolerant control fields The Author Dr. Linlin Li completed her dissertation under the supervision of Prof. Steven X. Ding at the Faculty of Engineering, University of Duisburg-Essen, Germany...

  11. Passive Fault Tolerant Control of Piecewise Affine Systems Based on H Infinity Synthesis

    DEFF Research Database (Denmark)

    Gholami, Mehdi; Cocquempot, vincent; Schiøler, Henrik

    2011-01-01

    In this paper we design a passive fault tolerant controller against actuator faults for discretetime piecewise affine (PWA) systems. By using dissipativity theory and H analysis, fault tolerant state feedback controller design is expressed as a set of Linear Matrix Inequalities (LMIs). In the cur...

  12. Cytokines affecting CD4+T regulatory cells in transplant tolerance. II. Interferon gamma (IFN-γ) promotes survival of alloantigen-specific CD4+T regulatory cells.

    Science.gov (United States)

    Nomura, Masaru; Hodgkinson, Suzanne J; Tran, Giang T; Verma, Nirupama D; Robinson, Catherine; Plain, Karren M; Boyd, Rochelle; Hall, Bruce M

    2017-06-01

    CD4 + T cells that transfer alloantigen-specific transplant tolerance are short lived in culture unless stimulated with specific-donor alloantigen and lymphocyte derived cytokines. Here, we examined if IFN-γ maintained survival of tolerance transferring CD4 + T cells. Alloantigen-specific transplant tolerance was induced in DA rats with heterotopic adult PVG heart allografts by a short course of immunosuppression and these grafts functioned for >100days with no further immunosuppression. In previous studies, we found the CD4 + T cells from tolerant rats that transfer tolerance to an irradiated DA host grafted with a PVG heart, lose their tolerance transferring ability after 3days of culture, either with or without donor alloantigen, and effect rejection of specific-donor grafts. If cultures with specific-donor alloantigen are supplemented by supernatant from ConA activated lymphocytes the tolerance transferring cells survive, suggesting these cells depend on cytokines for their survival. In this study, we found addition of rIFN-γ to MLC with specific-donor alloantigen maintained the capacity of tolerant CD4 + T cells to transfer alloantigen-specific tolerance and their ability to suppress PVG allograft rejection mediated by co-administered naïve CD4 + T cells. IFN-γ suppressed the in vitro proliferation of tolerant CD4 + T cells. Tolerant CD4 + CD25 + T cells did not proliferate in MLC to PVG stimulator cells with no cytokine added, but did when IFN-γ was present. IFN-γ did not alter proliferation of tolerant CD4 + CD25 + T cells to third-party Lewis. Tolerant CD4 + CD25 + T cells' expression of IFN-γ receptor (IFNGR) was maintained in culture when IFN-γ was present. This study suggested that IFN-γ maintained tolerance mediating alloantigen-specific CD4 + CD25 + T cells. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  13. Controlling fuel costs: Procurement strategies and regulatory standards

    International Nuclear Information System (INIS)

    Einhorn, H.A.; Levi, B.I.

    1992-01-01

    Since the oil price shocks and inflation of the 1970s, regulatory authorities and utilities have devoted considerable attention to controlling energy costs while maintaining reliable service. Although much of this concern has been directed towards capital cost containment, increasing scrutiny has been applied to a broad range of variable costs, especially to fuel procurement expenditures. With some 40% to 65% of the electric utility industry's annual operation and maintenance expenses paid to secure fuel supplies, even a small difference in fuel costs could have a substantial impact on costs to ratepayers. This increased attention to fuel cost containment can be expected to intensify as implementation of the 1990 amendments to the Clean Air Act affects fuel purchase decisions. To assure that fuel is purchased in a responsible and cost-effective manner, some state jurisdictions have initiated periodic reviews (audits) of the procurement practices that electric utilities follow when purchasing fuel. While a utility must demonstrate how it purchases fuel, there is wide variation in interest and scope of audits among jurisdictions. In this paper, the authors review: (1) the regulatory environment within which fuel procurement and audits occur, and (2) some particularly controversial issues that will receive increasing attention as the practice of conducting fuel procurement audits spreads

  14. Workshop on rules for exemption from regulatory control: Proceedings

    International Nuclear Information System (INIS)

    1989-04-01

    This conference report documents the proceedings of an International Workshop on the subject of exempting radiation sources and practices from regulatory control. The purpose of the workshop was to provide national regulatory authorities an opportunity to exchange information on their respective approaches and practices involving exemptions and to enhance international understanding and cooperation on the derivation and practical application of the underlying principles. In addition, input from the workshop was intended to assist the NRC in the development of a policy statement on this issue. The workshop was divided into five sessions. During the first four sessions, papers were presented which defined the relative terms and concepts, outlined the national situations and approaches to the establishment and development of exemption rules, identified and discussed the existing issues, and gave the status of the international guidelines on exemption rules. The fifth session was devoted to summarizing the workshop and identifying the areas of consensus, the outstanding issues and the areas for future work. Individual papers were processed separately for the data base

  15. Dual RNA regulatory control of a Staphylococcus aureus virulence factor.

    Science.gov (United States)

    Chabelskaya, Svetlana; Bordeau, Valérie; Felden, Brice

    2014-04-01

    In pathogens, the accurate programming of virulence gene expression is essential for infection. It is achieved by sophisticated arrays of regulatory proteins and ribonucleic acids (sRNAs), but in many cases their contributions and connections are not yet known. Based on genetic, biochemical and structural evidence, we report that the expression pattern of a Staphylococcus aureus host immune evasion protein is enabled by the collaborative actions of RNAIII and small pathogenicity island RNA D (SprD). Their combined expression profiles during bacterial growth permit early and transient synthesis of Sbi to avoid host immune responses. Together, these two sRNAs use antisense mechanisms to monitor Sbi expression at the translational level. Deletion analysis combined with structural analysis of RNAIII in complex with its novel messenger RNA (mRNA) target indicate that three distant RNAIII domains interact with distinct sites of the sbi mRNA and that two locations are deep in the sbi coding region. Through distinct domains, RNAIII lowers production of two proteins required for avoiding innate host immunity, staphylococcal protein A and Sbi. Toeprints and in vivo mutational analysis reveal a novel regulatory module within RNAIII essential for attenuation of Sbi translation. The sophisticated translational control of mRNA by two differentially expressed sRNAs ensures supervision of host immune escape by a major pathogen.

  16. Congestion control for vehicular delay tolerant network routing protocols

    OpenAIRE

    Oham, Chuka Finbars

    2014-01-01

    The Vehicular Delay Tolerant Network (VDTN) is a special and challenging type of the Delay Tolerant Network because of its high mobility, frequent disconnections and nodal congestion features. These challenging features make it prone to congestion which leads to a considerable amount of message drops in the network. To minimize the impact of congestion in the network, we designed and implemented the Congestion Aware Spray and Wait (CASaW) routing protocol. We varied the buffer sizes of the no...

  17. Fault Tolerant Flight Control Using Sliding Modes and Subspace Identification-Based Predictive Control

    KAUST Repository

    Siddiqui, Bilal A.; El-Ferik, Sami; Abdelkader, Mohamed

    2016-01-01

    In this work, a cascade structure of a time-scale separated integral sliding mode and model predictive control is proposed as a viable alternative for fault-tolerant control. A multi-variable sliding mode control law is designed as the inner loop of the flight control system. Subspace identification is carried out on the aircraft in closed loop. The identified plant is then used for model predictive controllers in the outer loop. The overall control law demonstrates improved robustness to measurement noise, modeling uncertainties, multiple faults and severe wind turbulence and gusts. In addition, the flight control system employs filters and dead-zone nonlinear elements to reduce chattering and improve handling quality. Simulation results demonstrate the efficiency of the proposed controller using conventional fighter aircraft without control redundancy.

  18. Fault Tolerant Flight Control Using Sliding Modes and Subspace Identification-Based Predictive Control

    KAUST Repository

    Siddiqui, Bilal A.

    2016-07-26

    In this work, a cascade structure of a time-scale separated integral sliding mode and model predictive control is proposed as a viable alternative for fault-tolerant control. A multi-variable sliding mode control law is designed as the inner loop of the flight control system. Subspace identification is carried out on the aircraft in closed loop. The identified plant is then used for model predictive controllers in the outer loop. The overall control law demonstrates improved robustness to measurement noise, modeling uncertainties, multiple faults and severe wind turbulence and gusts. In addition, the flight control system employs filters and dead-zone nonlinear elements to reduce chattering and improve handling quality. Simulation results demonstrate the efficiency of the proposed controller using conventional fighter aircraft without control redundancy.

  19. Validation of gamma irradiator controls for quality and regulatory compliance

    International Nuclear Information System (INIS)

    Harding, R.B.; Pinteric, F.J.A.

    1995-01-01

    Since 1978 the U.S. Food and Drug Administration (FDA) has had both the legal authority and the Current Good Manufacturing Practice (CGMP) regulations in place to require irradiator owners who process medical devices to produce evidence of Irradiation Process Validation. One of the key components of Irradiation Process Validation is the validation of the irradiator controls. However, it is only recently that FDA audits have focused on this component of the process validation. What is Irradiator Control System Validation? What constitutes evidence of control? How do owners obtain evidence? What is the irradiator supplier's role in validation? How does the ISO 9000 Quality Standard relate to the FDA's CGMP requirement for evidence of Control System Validation? This paper presents answers to these questions based on the recent experiences of Nordion's engineering and product management staff who have worked with several US-based irradiator owners. This topic - Validation of Irradiator Controls - is a significant regulatory compliance and operations issues within the irradiator suppliers' and users' community. (author)

  20. Evaluation of digital fault-tolerant architectures for nuclear power plant control systems

    International Nuclear Information System (INIS)

    Battle, R.E.

    1990-01-01

    Four fault tolerant architectures were evaluated for their potential reliability in service as control systems of nuclear power plants. The reliability analyses showed that human- and software-related common cause failures and single points of failure in the output modules are dominant contributors to system unreliability. The four architectures are triple-modular-redundant (TMR), both synchronous and asynchronous, and also dual synchronous and asynchronous. The evaluation includes a review of design features, an analysis of the importance of coverage, and reliability analyses of fault tolerant systems. An advantage of fault-tolerant controllers over those not fault tolerant, is that fault-tolerant controllers continue to function after the occurrence of most single hardware faults. However, most fault-tolerant controllers have single hardware components that will cause system failure, almost all controllers have single points of failure in software, and all are subject to common cause failures. Reliability analyses based on data from several industries that have fault-tolerant controllers were used to estimate the mean-time-between-failures of fault-tolerant controllers and to predict those failures modes that may be important in nuclear power plants. 7 refs., 4 tabs

  1. MATERNAL-FETAL TOLERANCE AS A MANIFESTATION OF REGULATORY CONTINUUM AND PLASTICITY OF THEIR IMMUNE SYSTEMS (in memory of I.P. Ashmarin

    Directory of Open Access Journals (Sweden)

    E. P. Kharchenko

    2011-01-01

    Full Text Available Abstract. Relations of immune tolerance between mother and fetus are considered in view of a common regulatory continuum which is formed under the influence of a growing fetus. To explain such an immune tolerance, a notion of immune system plasticity is introduced, as an analogue to the nervous system plasticity, which develops in response to a continuum of changes occurring in fetal and maternal organisms during the nine months of pregnancy. The immune system plasticity in females is supposed to be among possible factors causing collisions upon conception and in the course of pregnancy. (Med. Immunol., 2011, vol. 13, N 2-3, pp 121-132

  2. Drought Response in Wheat: Key Genes and Regulatory Mechanisms Controlling Root System Architecture and Transpiration Efficiency

    Directory of Open Access Journals (Sweden)

    Manoj Kulkarni

    2017-12-01

    Full Text Available Abiotic stresses such as, drought, heat, salinity, and flooding threaten global food security. Crop genetic improvement with increased resilience to abiotic stresses is a critical component of crop breeding strategies. Wheat is an important cereal crop and a staple food source globally. Enhanced drought tolerance in wheat is critical for sustainable food production and global food security. Recent advances in drought tolerance research have uncovered many key genes and transcription regulators governing morpho-physiological traits. Genes controlling root architecture and stomatal development play an important role in soil moisture extraction and its retention, and therefore have been targets of molecular breeding strategies for improving drought tolerance. In this systematic review, we have summarized evidence of beneficial contributions of root and stomatal traits to plant adaptation to drought stress. Specifically, we discuss a few key genes such as, DRO1 in rice and ERECTA in Arabidopsis and rice that were identified to be the enhancers of drought tolerance via regulation of root traits and transpiration efficiency. Additionally, we highlight several transcription factor families, such as, ERF (ethylene response factors, DREB (dehydration responsive element binding, ZFP (zinc finger proteins, WRKY, and MYB that were identified to be both positive and negative regulators of drought responses in wheat, rice, maize, and/or Arabidopsis. The overall aim of this review is to provide an overview of candidate genes that have been identified as regulators of drought response in plants. The lack of a reference genome sequence for wheat and non-transgenic approaches for manipulation of gene functions in wheat in the past had impeded high-resolution interrogation of functional elements, including genes and QTLs, and their application in cultivar improvement. The recent developments in wheat genomics and reverse genetics, including the availability of a

  3. Regulatory control of radioactivity and nuclear fuel cycle in Canada

    International Nuclear Information System (INIS)

    Hamel, P.E.; Jennekens, J.H.

    1977-01-01

    The mining of pitchblende for the extraction of radium some four decades ago resulted in a largely unwanted by-product, uranium, which set the stage for Canada to be one of the first countires in the world to embark upon a nuclear energy program. From this somewhat unusual beginning, the Canadian program expanded beyond mining of uranium-bearing ores to include extensive research and development in the field of radio-isotope applications, research and power reactors, nuclear-fuel conversion and fabrication facilities, heavy-water production plants and facilities for the management of radioactive wastes. As in the case of any major technological development, nuclear energy poses certain risks on the part of those directly engaged in the industry and on the part of the general public. What characterizes these risks is not so much their physical nature as the absence of long-term experience and the confidence resulting from it. The early development of regulatory controls in the nuclear field in Canada was very much influenced by security considerations but subsequently evolved to include radiological protection and safety requirements commensurate with the expanding application of nuclear energy to a wide spectrum of peaceful uses. A review of Canadian nuclear regulatory experience will reveal that the risks posed by the peaceful uses of nuclear energy can be controlled in such a manner as to ensure a high level of safety. Recent events and development have shown however that emphasis on the risks associated with low-probability, high-consequence events must not be allowed to mask the importance of health and safety measures covering the entire fuel cycle

  4. Regulatory control of nuclear safety in Finland. Annual report 1999

    International Nuclear Information System (INIS)

    Tossavainen, K.

    2000-06-01

    This report concerns the regulatory control of nuclear energy in Finland in 1999. Its submission to the Ministry of Trade and Industry by the Finnish Radiation and Nuclear Safety Authority (STUK) is stipulated in section 121 of the Nuclear Energy Decree. STUK's regulatory work was focused on the operation of the Finnish nuclear power plants as well as on nuclear waste management and safeguards of nuclear materials. The operation of the Finnish nuclear power plants was in compliance with the conditions set out in their operating licences and with current regulations, with the exception of some inadvertent deviations from the Technical Specifications. No plant events endangering the safe use of nuclear energy occurred. The individual doses of all nuclear power plant workers remained below the dose threshold. The collective dose of the workers was low, compared internationally, and did not exceed STUK's guidelines at either nuclear power plant. The radioactive releases were minor and the dose calculated on their basis for the most exposed individual in the vicinity of the plant was well below the limit established in a decision of the Council of State at both Loviisa and Olkiluoto nuclear power plants. STUK issued statements to the Ministry of Trade and Industry about the environmental impact assessment programme reports on the possible nuclear power plant projects at Olkiluoto and Loviisa and about the continued operation of the research reactor in Otaniemi, Espoo. A Y2k-related safety assessment of the Finnish nuclear power plants was completed in December. In nuclear waste management STUK's regulatory work was focused on spent fuel storage and final disposal plans as well as on the treatment, storage and final disposal of reactor waste. No events occurred in nuclear waste management that would have endangered safety. A statement was issued to the Ministry of Trade and Industry about an environmental impact assessment report on a proposed final disposal facility for

  5. Regulatory control of nuclear safety in Finland. Annual report 1999

    Energy Technology Data Exchange (ETDEWEB)

    Tossavainen, K. [ed.

    2000-06-01

    This report concerns the regulatory control of nuclear energy in Finland in 1999. Its submission to the Ministry of Trade and Industry by the Finnish Radiation and Nuclear Safety Authority (STUK) is stipulated in section 121 of the Nuclear Energy Decree. STUK's regulatory work was focused on the operation of the Finnish nuclear power plants as well as on nuclear waste management and safeguards of nuclear materials. The operation of the Finnish nuclear power plants was in compliance with the conditions set out in their operating licences and with current regulations, with the exception of some inadvertent deviations from the Technical Specifications. No plant events endangering the safe use of nuclear energy occurred. The individual doses of all nuclear power plant workers remained below the dose threshold. The collective dose of the workers was low, compared internationally, and did not exceed STUK's guidelines at either nuclear power plant. The radioactive releases were minor and the dose calculated on their basis for the most exposed individual in the vicinity of the plant was well below the limit established in a decision of the Council of State at both Loviisa and Olkiluoto nuclear power plants. STUK issued statements to the Ministry of Trade and Industry about the environmental impact assessment programme reports on the possible nuclear power plant projects at Olkiluoto and Loviisa and about the continued operation of the research reactor in Otaniemi, Espoo. A Y2k-related safety assessment of the Finnish nuclear power plants was completed in December. In nuclear waste management STUK's regulatory work was focused on spent fuel storage and final disposal plans as well as on the treatment, storage and final disposal of reactor waste. No events occurred in nuclear waste management that would have endangered safety. A statement was issued to the Ministry of Trade and Industry about an environmental impact assessment report on a proposed final

  6. Effective Regulatory Control of Radioactive Sources in Taiwan

    International Nuclear Information System (INIS)

    Liu, W.; Yuan, C.; Fan, S.; Su, S.

    2004-01-01

    Since the incident of radioactively contaminated buildings first surfaced in Taiwan in 1992, efforts have been made by AEC (Atomic Energy Council) of Taiwan to prevent recurrence of similar incidents involving radioactive materials and to achieve effective regulatory control over radioactive sources. The most important milestone is when AEC began to enforce IRPA he Ionizing Radiation Protection Act with the promulgation of 18 relevant regulations on Feb. 1, 2003. In order to enhance accountability of radioactive material and equipment capable of producing ionizing radiation, AEC develops and begins implementing a RPCS Radiation Protection Control System which is a powerful tool in controlling radiation safety and security. In addition, AEC develops a monthly registration program via internet, an o n-line reporting system f or owners/operators of radioactive sources, to improve monitoring of sealed sources (in-use and not-in-use). The registration requirement applies to 469 licensees possessing about 3,000 sealed sources in Taiwan. Because of the threat of orphan sources, AEC has made great efforts in preventing their contamination of construction steel material by establishing and enforcing the RPMMPIRCB Regulation for Preventive Measures and Management Plans for Incident of Radioactively Contaminated Buildings. To comply with this regulation, all 19 of Taiwan's steel factories with melting furnace have installed portal-type radiation detection system to monitor incoming scrap metal. (Author)

  7. Regulatory inspection: a powerful tool to control industrial radioactive sources

    International Nuclear Information System (INIS)

    Silva, F.C.A. da; Leocadio, J.C.; Ramalho, A.T.

    2008-01-01

    An important contribution for Brazilian development, especially for the quality control of products, is the use of radiation sources by conventional industries. There are in Brazil roughly 3,000 radioactive sources spread out among 950 industries. The main industrial practices involved are: industrial radiography, industrial irradiators, industrial accelerators, well logging petroleum and nuclear gauges. More than 1,800 Radiation Protection Officers (RPOs) were qualified to work in these practices. The present work presents a brief description of the safety control over industrial radioactive installations performed by the Brazilian Regulatory Authority, i.e. the National Commission of Nuclear Energy (CNEN). This paper also describes the national system for radiation safety inspections, the regulation infrastructure and the national inventory of industrial installations. The inspections are based on specific indicators, and their periodicity depends on the risk and type of installation. The present work discusses some relevant aspects that must be considered during the inspections, in order to make the inspections more efficient in controlling the sources. One of these aspects regards the evaluation of the storage place for the sources, a very important parameter for preventing future risky situations. (author)

  8. Fault-tolerant design of local controller for the poloidal field converter control system on ITER

    International Nuclear Information System (INIS)

    Shen, Jun; Fu, Peng; Gao, Ge; He, Shiying; Huang, Liansheng; Zhu, Lili; Chen, Xiaojiao

    2016-01-01

    Highlights: • The requirements on the Local Control Cubicles (LCC) for ITER Poloidal Field Converter are analyzed. • Decoupled service-based software architecture is proposed to make control loops on LCC running at varying cycle-time. • Fault detection and recovery methods for the LCC are developed to enhance the system. • The performance of the LCC with or without fault-tolerant feature is tested and compared. - Abstract: The control system for the Poloidal Field (PF) on ITER is a synchronously networked control system, which has several kinds of computational controllers. The Local Control Cubicles (LCC) play a critical role in the networked control system for they are the interface to all input and output signals. Thus, some additional work must be done to guarantee the LCCs proper operation under influence of faults. This paper mainly analyzes the system demands of the LCCs and faults which have been encountered recently. In order to handle these faults, decoupled service-based software architecture has been proposed. Based on this architecture, fault detection and system recovery methods, such as redundancy and rejuvenation, have been incorporated to achieve a fault-tolerant private network with the aid of QNX operating system. Unlike the conventional method, this method requires no additional hardware and can be achieved relatively easily. To demonstrate effectiveness the LCCs have been successfully tested during the recent PF Converter Unit performance tests for ITER.

  9. Fault-tolerant design of local controller for the poloidal field converter control system on ITER

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Jun; Fu, Peng; Gao, Ge; He, Shiying; Huang, Liansheng, E-mail: huangls@ipp.ac.cn; Zhu, Lili; Chen, Xiaojiao

    2016-11-15

    Highlights: • The requirements on the Local Control Cubicles (LCC) for ITER Poloidal Field Converter are analyzed. • Decoupled service-based software architecture is proposed to make control loops on LCC running at varying cycle-time. • Fault detection and recovery methods for the LCC are developed to enhance the system. • The performance of the LCC with or without fault-tolerant feature is tested and compared. - Abstract: The control system for the Poloidal Field (PF) on ITER is a synchronously networked control system, which has several kinds of computational controllers. The Local Control Cubicles (LCC) play a critical role in the networked control system for they are the interface to all input and output signals. Thus, some additional work must be done to guarantee the LCCs proper operation under influence of faults. This paper mainly analyzes the system demands of the LCCs and faults which have been encountered recently. In order to handle these faults, decoupled service-based software architecture has been proposed. Based on this architecture, fault detection and system recovery methods, such as redundancy and rejuvenation, have been incorporated to achieve a fault-tolerant private network with the aid of QNX operating system. Unlike the conventional method, this method requires no additional hardware and can be achieved relatively easily. To demonstrate effectiveness the LCCs have been successfully tested during the recent PF Converter Unit performance tests for ITER.

  10. [Individual, community, regulatory, and systemic approaches to tobacco control interventions].

    Science.gov (United States)

    Gorini, Giuseppe

    2011-01-01

    During the 60s and the 70s strategies for decreasing initiation or quitting have been developed, in order to find those with high success rates. Unfortunately, interventions with an individual approach involved few smokers, so their impact in decreasing smoking prevalence was limited. The socio-ecological model offers a theoretical framework to community interventions for smoking cessation developed during the 80s, in which smoking was considered not only an individual, but also a social problem. In the 80s and the 90s smoking cessation community trials were developed, such as the Community Intervention Trial for Smoking Cessation (COMMIT). Afterwards, policy interventions (price policy; smoking bans in public places; advertising bans; bans of sales to minors) were developed, such as the American Stop Smoking Intervention Study for Cancer Prevention (ASSIST). California has been the first State all over the world to develop a comprehensive Tobacco Control Program in 1988, becoming the place for an ever-conducted natural experiment. All policy interventions in tobacco control have been finally grouped together in the World Health Organization - Framework Convention on Tobacco Control (WHO-FCTC), the first Public Health Treaty. Study designs have changed, according to the individual, community, or regulatory approaches: the classical randomized controlled trials (RCTs), in which the sampling unit is the individual, have been carried out for the evaluation of smoking cessation treatments, whereas cluster RCTs, in which the sampling unit is the community, have been conducted for evaluating community interventions, such as COMMIT. Finally, quasi-experimental studies (before/after study; prospective cohorts, both with a control group), in which the observational unit is a State, have been used for evaluating tobacco control policies, such as ASSIST and the International Tobacco Control Policy Evaluation Project. Although the successes of the last 20 years, tobacco

  11. Cytokines affecting CD4+T regulatory cells in transplant tolerance. III. Interleukin-5 (IL-5) promotes survival of alloantigen-specific CD4+ T regulatory cells.

    Science.gov (United States)

    Hall, Bruce M; Plain, Karren M; Tran, Giang T; Verma, Nirupama D; Robinson, Catherine M; Nomura, Masaru; Boyd, Rochelle; Hodgkinson, Suzanne J

    2017-08-01

    CD4 + T cells mediate antigen-specific allograft tolerance, but die in culture without activated lymphocyte derived cytokines. Supplementation of the media with cytokine rich supernatant, from ConA activated spleen cells, preserves the capacity of tolerant cells to transfer tolerance and suppress rejection. rIL-2 or rIL-4 alone are insufficient to maintain these cells, however. We observed that activation of naïve CD4 + CD25 + FOXP3 + Treg with alloantigen and the Th2 cytokine rIL-4 induces them to express interleukin-5 specific receptor alpha (IL-5Rα) suggesting that IL-5, a Th2 cytokine that is produced later in the immune response may promote tolerance mediating Treg. This study examined if recombinant IL-5(rIL-5) promoted survival of tolerant CD4 + , especially CD4 + CD25 + T cells. CD4 + T cells, from DA rats tolerant to fully allogeneic PVG heart allografts surviving over 100days without on-going immunosuppression, were cultured with PVG alloantigen and rIL-5. The ability of these cells to adoptively transfer tolerance to specific-donor allograft and suppress normal CD4 + T cell mediated rejection in adoptive DA hosts was examined. Tolerant CD4 + CD25 + T cells' response to rIL-5 and expression of IL-5Rα was also assessed. rIL-5 was sufficient to promote transplant tolerance mediating CD4 + T cells' survival in culture with specific-donor alloantigen. Tolerant CD4 + T cells cultured with rIL-5 retained the capacity to transfer alloantigen-specific tolerance and inhibited naïve CD4 + T cells' capacity to effect specific-donor graft rejection. rIL-5 promoted tolerant CD4 + CD25 + T cells' proliferation in vitro when stimulated with specific-donor but not third-party stimulator cells. Tolerant CD4 + CD25 + T cells expressed IL-5Rα. This study demonstrated that IL-5 promoted the survival of alloantigen-specific CD4 + CD25 + T cells that mediate transplant tolerance. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Passive Fault-tolerant Control of Discrete-time Piecewise Affine Systems against Actuator Faults

    DEFF Research Database (Denmark)

    Tabatabaeipour, Seyed Mojtaba; Izadi-Zamanabadi, Roozbeh; Bak, Thomas

    2012-01-01

    In this paper, we propose a new method for passive fault-tolerant control of discrete time piecewise affine systems. Actuator faults are considered. A reliable piecewise linear quadratic regulator (LQR) state feedback is designed such that it can tolerate actuator faults. A sufficient condition f...... is illustrated on a numerical example and a two degree of freedom helicopter....

  13. Modular Multilevel Converter Control Strategy with Fault Tolerance

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Eni, Emanuel-Petre; Mathe, Laszlo

    2013-01-01

    The Modular Multilevel Converter (MMC) technology has recently emerged in VSC-HVDC applications where it demonstrated higher efficiency and fault tolerance compared to the classical 2-level topology. Due to the ability of MMC to connect to HV levels, MMC can be also used in transformerless STATCOM...

  14. Regulatory system for control of nuclear facilities in Bangladesh

    International Nuclear Information System (INIS)

    Mollah, A.S.

    2005-01-01

    All human activities have associated risks. Nuclear programme is no exception. The Bangladesh Atomic Energy Commission (BAEC), constituted in February 1973 through the promulgation of the Presidential order 15 of 1973. Functions of BAEC include research and development in peaceful application of atomic energy, generation of electricity and promotion of international relations congenial to implementation of its programmes and projects. In 1993 the Government of Bangladesh promulgated the law on Nuclear Safety and Radiation Control. Considering the human resources, expertise and facilities needed for implementation of the provisions of the NSRC law, BAEC was entrusted with the responsibility to enforce it. The responsibilities of the BAEC cover nuclear and radiological safety within the installations of BAEC and radiological safety in the manifold applications of radioisotopes and radiation sources within the country. An adequate and competent infrastructure has been built to cater to the diverse nuclear and radiation protection requirements of all nuclear facilities in Bangladesh, arising at different stages from site selection to day-to-day operation. In addition, periodic inspections of the nuclear facilities are carried out. The licensing and regulatory inspection systems for controlling of nuclear installations and radiation sources are established. The paper describes the legal provisions, responsibilities and organization of BAEC with special emphasis on nuclear safety and radiation protection of nuclear facilities in Bangladesh. (author)

  15. Regulatory control of Chinese Proprietary Medicines in Singapore.

    Science.gov (United States)

    Yee, Shen-Kuan; Chu, Swee-Seng; Xu, Yi-Min; Choo, Peck-Lin

    2005-02-01

    In Singapore, there has been a growing public interest in traditional Chinese medicine (TCM), which plays an important role in the healthcare system. With effect from 1 September 1999, the control on Chinese Proprietary Medicines (CPM) was implemented in three phases over a span of 3 years. Under the CPM regulatory framework, CPM importers, wholesalers, manufacturers and re-packers must be licensed and CPM products assessed and listed by the health authority before they are allowed for sale. Product assessment is based on the criteria of safety and quality which include limits of toxic heavy metals and microbial contents. During the 3-year CPM listing exercise, irregularities were detected, including intrinsic toxicity, adulteration, substitution, contamination, misidentification, non-traditional and/or inappropriate usage, incorrect preparation, inappropriate labelling, exaggerated claims and/or advertising. The full implementation of CPM control by September 2001 saw the listing of 7943 CPM products and brought about an improvement in the quality and safety of CPM in Singapore as well as the removal of sub-standard, fake/imitation and adulterated products. The standards of practices by local CPM dealers have also been raised. These improvements have, in turn, increased the level of public confidence in CPM products in Singapore.

  16. LOW-INCOME, MINORITY FATHERS’ CONTROL STRATEGIES AND THEIR CHILDREN'S REGULATORY SKILLS

    OpenAIRE

    Malin, Jenessa L.; Cabrera, Natasha J.; Karberg, Elizabeth; Aldoney, Daniela; Rowe, Meredith Lee

    2014-01-01

    The current study explored the bidirectional association of children's individual characteristics, fathers' control strategies at 24-months and children's regulatory skills at pre-kindergarten (pre-K). Using a sample of low-income minority families with 2-year-olds from the Early Head Start Evaluation Research Program (n = 71) we assessed the association between child gender and vocabulary skills, fathers' control strategies at 24-months (e.g., regulatory behavior and regulatory language), an...

  17. Development Status of the Rad-Tolerant TTEthernet Controller

    Science.gov (United States)

    Fidi, Christian; van Masar, Ivan

    2016-08-01

    The use of switched networking technologies for aerospace and more recently automotive brings additional advantages for space applications like the increase in performance of the overall avionics of a spacecraft. These networks are characterized by a central device (switch) and a point-to-point structure between switch and terminal devices that eases electrical and logical insulation.However, for a use in highly-reliable or highly-available applications as in launchers or satellites systems, these network technologies need to provide built-in determinism and redundancy to fulfill the tight latency and jitter requirements of the avionics control loops and the respective hardware redundancy. Therefore a state of the art networking technology already provides these features and allows the modularity and scalability to be used for the different space applications and would allow combining the deterministic avionics with the high speed payload network in a spacecraft [1].Introducing the time-triggered principle to Ethernet allows combining the open industry standard IEE802.3 Ethernet currently use in almost all GSE platforms, with full control of latency and jitter of the time-triggered approach. To allow the time-triggered data flow over Ethernet, a network- wide synchronization time-base has to be established to allow deriving all network events on a globally known time which is typically done in software in almost all spacecrafts. The additional synchronization service of Time-triggered Ethernet has been implemented as additional quality of service (QoS) on layer 2 of the ISO/OSI network model and been standardized in the SAE AS6802 [3].Within a launcher, the communication system ensured the data exchanges between avionic functions during all phases of the launcher lifecycle which is composed of three areas: AIT operations, ground phase and flight phase. To ensure the use of a single network for the different phases, the network needs to support features like the

  18. Database mirroring in fault-tolerant continuous technological process control

    Directory of Open Access Journals (Sweden)

    R. Danel

    2015-10-01

    Full Text Available This paper describes the implementations of mirroring technology of the selected database systems – Microsoft SQL Server, MySQL and Caché. By simulating critical failures the systems behavior and their resilience against failure were tested. The aim was to determine whether the database mirroring is suitable to use in continuous metallurgical processes for ensuring the fault-tolerant solution at affordable cost. The present day database systems are characterized by high robustness and are resistant to sudden system failure. Database mirroring technologies are reliable and even low-budget projects can be provided with a decent fault-tolerant solution. The database system technologies available for low-budget projects are not suitable for use in real-time systems.

  19. Design of passive fault-tolerant controllers of a quadrotor based on sliding mode theory

    Directory of Open Access Journals (Sweden)

    Merheb Abdel-Razzak

    2015-09-01

    Full Text Available Abstract In this paper, sliding mode control is used to develop two passive fault tolerant controllers for an AscTec Pelican UAV quadrotor. In the first approach, a regular sliding mode controller (SMC augmented with an integrator uses the robustness property of variable structure control to tolerate partial actuator faults. The second approach is a cascaded sliding mode controller with an inner and outer SMC loops. In this configuration, faults are tolerated in the fast inner loop controlling the velocity system. Tuning the controllers to find the optimal values of the sliding mode controller gains is made using the ecological systems algorithm (ESA, a biologically inspired stochastic search algorithm based on the natural equilibrium of animal species. The controllers are tested using SIMULINK in the presence of two different types of actuator faults, partial loss of motor power affecting all the motors at once, and partial loss of motor speed. Results of the quadrotor following a continuous path demonstrated the effectiveness of the controllers, which are able to tolerate a significant number of actuator faults despite the lack of hardware redundancy in the quadrotor system. Tuning the controller using a faulty system improves further its ability to afford more severe faults. Simulation results show that passive schemes reserve their important role in fault tolerant control and are complementary to active techniques

  20. Tolerance of Volume Control Noninvasive Ventilation in Subjects With Amyotrophic Lateral Sclerosis.

    Science.gov (United States)

    Martínez, Daniel; Sancho, Jesús; Servera, Emilio; Marín, Julio

    2015-12-01

    Noninvasive ventilation (NIV) tolerance has been identified as an independent predictor of survival in amyotrophic lateral sclerosis (ALS). Volume control continuous mandatory ventilation (VC-CMV) NIV has been associated with poor tolerance. The aim of this study was to determine the tolerance of subjects with ALS to VC-CMV NIV. This was a prospective study involving subjects with ALS who were treated with VC-CMV NIV. Respiratory and functional parameters were recorded when the subjects began ventilatory support. NIV tolerance was evaluated after 3 months. Eighty-seven subjects with ALS were included. After 3 months, 80 subjects (92%) remained tolerant of NIV. Tolerant subjects presented greater survival (median 22.0 months, 95% CI 14.78-29.21) than intolerant subjects (median 6.0 months, 95% CI 0.86-11.13) (P = .03). The variables that best predicted NIV tolerance were mechanically assisted cough peak flow (P = .01) and percentage of time spent with SpO2 NIV (P = .03) CONCLUSIONS: VC-CMV NIV provides high rates of NIV tolerance in subjects with ALS. Mechanically assisted cough peak flow and percentage of time spent with SpO2 NIV are the 2 factors associated with tolerance of VC-CMV NIV in subjects with ALS. Copyright © 2015 by Daedalus Enterprises.

  1. Regulatory control in the rehabilitation of contaminated sites in Syria

    International Nuclear Information System (INIS)

    Shweikani, R.; Suman, H.

    2002-01-01

    The work described in this paper is concerning the regulatory control set by the Atomic Energy Commission of Syria (AECS) for the contaminated sites with Naturally Occurring Radioactive Materials (NORM) in the oil industries in the northeast of Syria. These sites lie in a desert region with poor population density and low occupancy. The decision was made to use the activity concentration of 226 Ra per unit mass as a measure to identify the need for cleanup. Two limits were set for this purpose so that contamination concentration above the higher limit is defined as waste that has to be excavated from the site, while contamination concentration between the two limits can be dealt with on site. Contamination concentration below the lower limit was looked at as acceptable. Remediation plan to transfer the contaminated soil, with radium concentration over the higher limit, to an engineered disposal pit was adopted. Proper stabilisation measures and environmental monitoring programme were requested by the AECS and considered as essential parts of the remediation plan. (author)

  2. Towards Robust Predictive Fault–Tolerant Control for a Battery Assembly System

    Directory of Open Access Journals (Sweden)

    Seybold Lothar

    2015-12-01

    Full Text Available The paper deals with the modeling and fault-tolerant control of a real battery assembly system which is under implementation at the RAFI GmbH company (one of the leading electronic manufacturing service providers in Germany. To model and control the battery assembly system, a unified max-plus algebra and model predictive control framework is introduced. Subsequently, the control strategy is enhanced with fault-tolerance features that increase the overall performance of the production system being considered. In particular, it enables tolerating (up to some degree mobile robot, processing and transportation faults. The paper discusses also robustness issues, which are inevitable in real production systems. As a result, a novel robust predictive fault-tolerant strategy is developed that is applied to the battery assembly system. The last part of the paper shows illustrative examples, which clearly exhibit the performance of the proposed approach.

  3. Internal Leakage Fault Detection and Tolerant Control of Single-Rod Hydraulic Actuators

    Directory of Open Access Journals (Sweden)

    Jianyong Yao

    2014-01-01

    Full Text Available The integration of internal leakage fault detection and tolerant control for single-rod hydraulic actuators is present in this paper. Fault detection is a potential technique to provide efficient condition monitoring and/or preventive maintenance, and fault tolerant control is a critical method to improve the safety and reliability of hydraulic servo systems. Based on quadratic Lyapunov functions, a performance-oriented fault detection method is proposed, which has a simple structure and is prone to implement in practice. The main feature is that, when a prescribed performance index is satisfied (even a slight fault has occurred, there is no fault alarmed; otherwise (i.e., a severe fault has occurred, the fault is detected and then a fault tolerant controller is activated. The proposed tolerant controller, which is based on the parameter adaptive methodology, is also prone to realize, and the learning mechanism is simple since only the internal leakage is considered in parameter adaptation and thus the persistent exciting (PE condition is easily satisfied. After the activation of the fault tolerant controller, the control performance is gradually recovered. Simulation results on a hydraulic servo system with both abrupt and incipient internal leakage fault demonstrate the effectiveness of the proposed fault detection and tolerant control method.

  4. Adolescent threat-related interpretive bias and its modification: the moderating role of regulatory control

    NARCIS (Netherlands)

    Salemink, E.; Wiers, R.W.

    2012-01-01

    Dual process models describe psychopathology as the consequence of an imbalance between a fast, impulsive system and a regulatory control system and have recently been applied to anxiety disorders. The aim of the current study was to specifically examine the role of a regulatory control system in

  5. Authority Defied : Need for Cognitive Closure Influences Regulatory Control When Resisting Authority

    NARCIS (Netherlands)

    Damen, Tom G. E.; van Leeuwen, Matthijs L.; Dijksterhuis, Ap; van Baaren, Rick B.

    The present studies examined whether differences in need for cognitive closure (NCC) were related to differences in regulatory control when confronted with authority. In two studies, levels of regulatory control were measured when participants resisted (Study 1; N = 46) or prepared to resist the

  6. Authority Defied: Need for Cognitive Closure Influences Regulatory Control When Resisting Authority

    NARCIS (Netherlands)

    Damen, T.G.E.; Leeuwen, M.L. van; Dijksterhuis, A.J.; Baaren, R.B. van

    2014-01-01

    The present studies examined whether differences in need for cognitive closure (NCC) were related to differences in regulatory control when confronted with authority. In two studies, levels of regulatory control were measured when participants resisted (Study 1; N = 46) or prepared to resist the

  7. Industrial Cost-Benefit Assessment for Fault-tolerant Control Systems

    DEFF Research Database (Denmark)

    Thybo, C.; Blanke, M.

    1998-01-01

    Economic aspects are decisive for industrial acceptance of research concepts including the promising ideas in fault tolerant control. Fault tolerance is the ability of a system to detect, isolate and accommodate a fault, such that simple faults in a sub-system do not develop into failures....... The objective of this paper is to help, in the early product development state, to find the economical most suitable scheme. A salient result is that with increased customer awareness of total cost of ownership, new products can benefit significantly from applying fault tolerant control principles....

  8. Regulatory control of radiation sources and radioactive materials in the Czech Republic

    International Nuclear Information System (INIS)

    Drabova, D.; Prouza, Z.

    2001-01-01

    The paper describes legal and regulatory provisions for radiation protection and safe use of sources of ionizing radiation in the Czech Republic with special emphasis on aspects of bringing activities under regulatory control and releasing them from it. It covers the development of a new legal framework, the work of the regulatory body, an overview of sources in use and provisions to achieve effective regulatory control of facilities and releases of radioactive material into the environment. Also, it describes reported unusual events with a proposed scheme for their classification and evaluation. (author)

  9. Evaluation of digital fault-tolerant architectures for nuclear power plant control systems

    International Nuclear Information System (INIS)

    Battle, R.E.

    1990-01-01

    This paper reports on four fault-tolerant architectures that were evaluated for their potential reliability in service as control systems of nuclear power plants. The reliability analyses showed that human- and software-related common cause failures and single points of failure in the output modules are dominant contributors to system unreliability. The four architectures are triple-modular-redundant, both synchronous and asynchronous, and also dual synchronous and asynchronous. The evaluation includes a review of design features, an analysis of the importance of coverage, and reliability analyses of fault-tolerant systems. Reliability analyses based on data from several industries that have fault-tolerant controllers were used to estimate the mean-time-between-failures of fault-tolerant controllers and to predict those failure modes that may be important in nuclear power plants

  10. Usnic acid controls the acidity tolerance of lichens

    International Nuclear Information System (INIS)

    Hauck, Markus; Juergens, Sascha-Rene

    2008-01-01

    The hypotheses were tested that, firstly, lichens producing the dibenzofuran usnic acid colonize substrates characterized by specific pH ranges, secondly, this preferred pH is in a range where soluble usnic acid and its corresponding anion occur in similar concentrations, and thirdly, usnic acid makes lichens vulnerable to acidity. Lichens with usnic acid prefer an ambient pH range between 3.5 and 5.5 with an optimum between 4.0 and 4.5. This optimum is close to the pK a1 value of usnic acid of 4.4. Below this optimum pH, dissolved SO 2 reduces the chlorophyll fluorescence yield more in lichens with than without their natural content of usnic acid. This suggests that usnic acid influences the acidity tolerance of lichens. The putative mechanism of the limited acidity tolerance of usnic acid-containing lichens is the acidification of the cytosol by molecules of protonated usnic acid shuttling protons through the plasma membrane at an apoplastic pH a1 . - Combined field and experimental data suggest that usnic acid makes lichens sensitive to acidity at pH <3.5

  11. The IAEA Regional Training Course on Regulatory Control of Radiation Sources

    International Nuclear Information System (INIS)

    2000-01-01

    Materials of the IAEA Regional Training Course contains 8 presented lectures. Authors deals with regulatory control of radiation sources. The next materials of the IAEA were presented: Organization and implementation of a national regulatory infrastructure governing protection against ionizing radiation and the safety of radiation sources. (IAEA-TECDOC-1067); Safety assessment plants for authorization and inspection of radiation sources (IAEA-TECDOC-1113); Regulatory authority information system RAIS, Version 2.0, Instruction manual

  12. Data-driven design of fault diagnosis and fault-tolerant control systems

    CERN Document Server

    Ding, Steven X

    2014-01-01

    Data-driven Design of Fault Diagnosis and Fault-tolerant Control Systems presents basic statistical process monitoring, fault diagnosis, and control methods, and introduces advanced data-driven schemes for the design of fault diagnosis and fault-tolerant control systems catering to the needs of dynamic industrial processes. With ever increasing demands for reliability, availability and safety in technical processes and assets, process monitoring and fault-tolerance have become important issues surrounding the design of automatic control systems. This text shows the reader how, thanks to the rapid development of information technology, key techniques of data-driven and statistical process monitoring and control can now become widely used in industrial practice to address these issues. To allow for self-contained study and facilitate implementation in real applications, important mathematical and control theoretical knowledge and tools are included in this book. Major schemes are presented in algorithm form and...

  13. Active fault-tolerant control strategy of large civil aircraft under elevator failures

    Directory of Open Access Journals (Sweden)

    Wang Xingjian

    2015-12-01

    Full Text Available Aircraft longitudinal control is the most important actuation system and its failures would lead to catastrophic accident of aircraft. This paper proposes an active fault-tolerant control (AFTC strategy for civil aircraft with different numbers of faulty elevators. In order to improve the fault-tolerant flight control system performance and effective utilization of the control surface, trimmable horizontal stabilizer (THS is considered to generate the extra pitch moment. A suitable switching mechanism with performance improvement coefficient is proposed to determine when it is worthwhile to utilize THS. Furthermore, AFTC strategy is detailed by using model following technique and the proposed THS switching mechanism. The basic fault-tolerant controller is designed to guarantee longitudinal control system stability and acceptable performance degradation under partial elevators failure. The proposed AFTC is applied to Boeing 747-200 numerical model and simulation results validate the effectiveness of the proposed AFTC approach.

  14. Nasal tolerance induces antigen-specific CD4+CD25- regulatory T cells that can transfer their regulatory capacity to naive CD4+ T cells.

    NARCIS (Netherlands)

    Unger, W.W.J.; Jansen, W.; Wolvers, DA; Halteren, van AG; Kraal, G.; Samsom, J.N.

    2003-01-01

    The mucosal immune system is uniquely adapted to elicit immune responses against pathogens but also to induce tolerogenic responses to harmless antigens. In mice, nasal application of ovalbumin (OVA) leads to suppression of both T(h)1 and T(h)2 responses. This tolerance can be transferred to naive

  15. Industrial Cost-Benefit Assessment for Fault-tolerant Control Systems

    DEFF Research Database (Denmark)

    Thybo, Claus; Blanke, Mogens

    1998-01-01

    Economic aspects are decisive for industrial acceptance of research concepts including the promising ideas in fault tolerant control. Fault tolerance is the ability of a system to detect, isolate and accommodate a fault, such that simple faults in a sub-system do not develop into failures...... at a system level. In a design phase for an industrial system, possibilities span from fail safe design where any single point failure is accommodated by hardware, over fault-tolerant design where selected faults are handled without extra hardware, to fault-ignorant design where no extra precaution is taken...

  16. Regulatory control and management of radioactive materials in the Philippines

    International Nuclear Information System (INIS)

    Borras, A.M.; Parami, V.K.; Domondon, D.B.

    2001-01-01

    The Philippine Nuclear Research Institute (PNRI) by virtue of Republic Act 2067, as amended, Republic Act 5207 and Executive Order 128 (1987), was mandated to promote, advance and regulate the safe and peaceful applications of nuclear science and technology in the Philippines. The PNRI was formerly the Philippine Atomic Energy Commission, established in 1958. This report aims to share the information and experience of PNRI as a regulatory authority on the administrative, technical and managerial aspects to ensure the safety and security of radioactive material in the country. It describes the country's regulatory framework, operational experiences, international co-operation including reporting system and database, and radiological safety assessment and compliance monitoring. It also briefly discusses the current development of the country's radiological emergency response plan and the radiation protection services offered by the PNRI. In the discussion and recommendations, some of the results of the regulatory information conferences conducted with the end-users are enumerated. (author)

  17. Small RNA-Controlled Gene Regulatory Networks in Pseudomonas putida

    DEFF Research Database (Denmark)

    Bojanovic, Klara

    evolved numerous mechanisms to controlgene expression in response to specific environmental signals. In addition to two-component systems, small regulatory RNAs (sRNAs) have emerged as major regulators of gene expression. The majority of sRNAs bind to mRNA and regulate their expression. They often have...... multiple targets and are incorporated into large regulatory networks and the RNA chaper one Hfq in many cases facilitates interactions between sRNAs and their targets. Some sRNAs also act by binding to protein targets and sequestering their function. In this PhD thesis we investigated the transcriptional....... Detailed insights into the mechanisms through which P. putida responds to different stress conditions and increased understanding of bacterial adaptation in natural and industrial settings were gained. Additionally, we identified genome-wide transcription start sites, andmany regulatory RNA elements...

  18. Diagnosis and Fault-Tolerant Control for Thruster-Assisted Position Mooring System

    DEFF Research Database (Denmark)

    Nguyen, Trong Dong; Blanke, Mogens; Sørensen, Asgeir

    2007-01-01

    Development of fault-tolerant control systems is crucial to maintain safe operation of o®shore installations. The objective of this paper is to develop a fault- tolerant control for thruster-assisted position mooring (PM) system with faults occurring in the mooring lines. Faults in line......'s pretension or line breaks will degrade the performance of the positioning of the vessel. Faults will be detected and isolated through a fault diagnosis procedure. When faults are detected, they can be accommodated through the control action in which only parameter of the controlled plant has to be updated...... to cope with the faulty condition. Simulations will be carried out to verify the advantages of the fault-tolerant control strategy for the PM system....

  19. Regulatory philosophy and requirements for radiation control in Canadian uranium mine-mill facilities

    International Nuclear Information System (INIS)

    Dory, A.B.

    1981-10-01

    With the point made that radiation exposure is one of the health hazards of uranium mining and accordingly has to be controlled, the Canadian regulatory philosophy is outlined as it pertains to the uranium mining industry. Two extremes in regulatory approach are examined, and the joint regulatory process is explained. Two examples of poor management performance are given, and the role of mine unions in the regulatory process is touched upon. The development of new regulations to cover ventilation and employee training is sketched briefly. The author concludes with a general expression of objectives for the eighties which include improved personal dosimetry

  20. Genetic control of mammalian T-cell proliferation with synthetic RNA regulatory systems

    OpenAIRE

    Chen, Yvonne Y.; Jensen, Michael C.; Smolke, Christina D.

    2010-01-01

    RNA molecules perform diverse regulatory functions in natural biological systems, and numerous synthetic RNA-based control devices that integrate sensing and gene-regulatory functions have been demonstrated, predominantly in bacteria and yeast. Despite potential advantages of RNA-based genetic control strategies in clinical applications, there has been limited success in extending engineered RNA devices to mammalian gene-expression control and no example of their application to functional res...

  1. A Design Method for Fault Reconfiguration and Fault-Tolerant Control of a Servo Motor

    Directory of Open Access Journals (Sweden)

    Jing He

    2013-01-01

    Full Text Available A design scheme that integrates fault reconfiguration and fault-tolerant position control is proposed for a nonlinear servo system with friction. Analysis of the non-linear friction torque and fault in the system is used to guide design of a sliding mode position controller. A sliding mode observer is designed to achieve fault reconfiguration based on the equivalence principle. Thus, active fault-tolerant position control of the system can be realized. A real-time simulation experiment is performed on a hardware-in-loop simulation platform. The results show that the system reconfigures well for both incipient and abrupt faults. Under the fault-tolerant control mechanism, the output signal for the system position can rapidly track given values without being influenced by faults.

  2. A modal H∞-norm-based performance requirement for damage-tolerant active controller design

    Science.gov (United States)

    Genari, Helói F. G.; Mechbal, Nazih; Coffignal, Gérard; Nóbrega, Eurípedes G. O.

    2017-04-01

    Damage-tolerant active control (DTAC) is a recent research area that encompasses control design methodologies resulting from the application of fault-tolerant control methods to vibration control of structures subject to damage. The possibility of damage occurrence is not usually considered in the active vibration control design requirements. Damage changes the structure dynamics, which may produce unexpected modal behavior of the closed-loop system, usually not anticipated by the controller design approaches. A modal H∞ norm and a respective robust controller design framework were recently introduced, and this method is here extended to face a new DTAC strategy implementation. Considering that damage affects each vibration mode differently, this paper adopts the modal H∞ norm to include damage as a design requirement. The basic idea is to create an appropriate energy distribution over the frequency range of interest and respective vibration modes, guaranteeing robustness, damage tolerance, and adequate overall performance, taking into account that it is common to have previous knowledge of the structure regions where damage may occur during its operational life. For this purpose, a structural health monitoring technique is applied to evaluate modal modifications caused by damage. This information is used to create modal weighing matrices, conducting to the modal H∞ controller design. Finite element models are adopted for a case study structure, including different damage severities, in order to validate the proposed control strategy. Results show the effectiveness of the proposed methodology with respect to damage tolerance.

  3. Evaporator unit as a benchmark for plug and play and fault tolerant control

    DEFF Research Database (Denmark)

    Izadi-Zamanabadi, Roozbeh; Vinther, Kasper; Mojallali, Hamed

    2012-01-01

    This paper presents a challenging industrial benchmark for implementation of control strategies under realistic working conditions. The developed control strategies should perform in a plug & play manner, i.e. adapt to varying working conditions, optimize their performance, and provide fault...... tolerance. A fault tolerant strategy is needed to deal with a faulty sensor measurement of the evaporation pressure. The design and algorithmic challenges in the control of an evaporator include: unknown model parameters, large parameter variations, varying loads, and external discrete phenomena...... such as compressor switch on/o or abrupt change in compressor speed....

  4. Low-income minority fathers' control strategies and children's regulatory skills

    Science.gov (United States)

    Malin, Jenessa L.; Cabrera, Natasha J.; Karberg, Elizabeth; Aldoney, Daniela; Rowe, Meredith

    2015-01-01

    The current study explored the bidirectional association of children's individual characteristics, fathers' control strategies at 24-months and children's regulatory skills at pre-kindergarten (pre-K). Using a sample of low-income minority families with 2-year-olds from the Early Head Start Evaluation Research Program (n = 71) we assessed the association between child gender and vocabulary skills, fathers' control strategies at 24-months (e.g., regulatory behavior and regulatory language), and children's sustained attention and emotion regulation at pre-kindergarten. There were three main findings. First, fathers' overwhelmingly use commands (e.g., do that) to promote compliance in their 24-month old children. Second, children's vocabulary skills predict fathers' regulatory behaviors during a father-child interaction, whereas children's gender predicts fathers' regulatory language during an interaction. Third, controlling for maternal supportiveness, fathers' regulatory behaviors at 24-months predict children's sustained attention at pre-kindergarten whereas fathers' regulatory language at 24-months predicts children's emotion regulation at pre-kindergarten. Our findings highlight the importance of examining paternal contributions to children's regulatory skills. PMID:25798496

  5. Low-income, minority fathers' control strategies and their children's regulatory skills.

    Science.gov (United States)

    Malin, Jenessa L; Cabrera, Natasha J; Karberg, Elizabeth; Aldoney, Daniela; Rowe, Meredith L

    2014-01-01

    The current study explored the bidirectional association of children's individual characteristics, fathers' control strategies at 24 months, and children's regulatory skills at prekindergarten (pre-K). Using a sample of low-income, minority families with 2-year-olds from the Early Head Start Research and Evaluation Project (n = 71), we assessed the association between child gender and vocabulary skills, fathers' control strategies at 24 months (e.g., regulatory behavior and regulatory language), and children's sustained attention and emotion regulation at prekindergarten. There were three main findings. First, fathers overwhelmingly used commands (e.g., "Do that.") to promote compliance in their 24-month-old children. Second, children's vocabulary skills predicted fathers' regulatory behaviors during a father-child interaction whereas children's gender predicted fathers' regulatory language during an interaction. Third, controlling for maternal supportiveness, fathers' regulatory behaviors at 24 months predicted children's sustained attention at pre-K whereas fathers' regulatory language at 24 months predicted children's emotion regulation at pre-K. Our findings highlight the importance of examining paternal contributions to children's regulatory skills. © 2014 Michigan Association for Infant Mental Health.

  6. Fault-tolerant reference generation for model predictive control with active diagnosis of elevator jamming faults

    NARCIS (Netherlands)

    Ferranti, L.; Wan, Y.; Keviczky, T.

    2018-01-01

    This paper focuses on the longitudinal control of an Airbus passenger aircraft in the presence of elevator jamming faults. In particular, in this paper, we address permanent and temporary actuator jamming faults using a novel reconfigurable fault-tolerant predictive control design. Due to their

  7. Fault tolerant control of wind turbines using unknown input observers

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2012-01-01

    This paper presents a scheme for accommodating faults in the rotor and generator speed sensors in a wind turbine. These measured values are important both for the wind turbine controller as well as the supervisory control of the wind turbine. The scheme is based on unknown input observers, which...

  8. Aircraft Attitude Distributed Fault-tolerant Control Based on Dynamic Actuator

    Directory of Open Access Journals (Sweden)

    Zhou Hong-Cheng

    2014-09-01

    Full Text Available For attitude control system, based on decentralized fault-tolerant control framework, actuators damage and stuck fault detection and identification unit are designed for the flight control system. And observer-based auxiliary system unit is also designed. The auxiliary system implies control surface damage faults and disturbances information. Firstly, we give the attitude control system under actuator stuck, lose of effectiveness, and control surface damages faults. Secondly, a multi-observer is designed for actuator fault detection and identification using a decision-making mechanism to determine current actuator failure modes. Then, an adaptive sliding mode observer is designed for implicit control surface damages and interference information. The reconfigurable controller can achieve fault tolerant using the information of adaptive sliding mode observer. Finally, the simulation results show the effectiveness of the proposed method.

  9. Plant-based oral tolerance to hemophilia therapy employs a complex immune regulatory response including LAP+CD4+ T cells.

    Science.gov (United States)

    Wang, Xiaomei; Su, Jin; Sherman, Alexandra; Rogers, Geoffrey L; Liao, Gongxian; Hoffman, Brad E; Leong, Kam W; Terhorst, Cox; Daniell, Henry; Herzog, Roland W

    2015-04-09

    Coagulation factor replacement therapy for the X-linked bleeding disorder hemophilia is severely complicated by antibody ("inhibitor") formation. We previously found that oral delivery to hemophilic mice of cholera toxin B subunit-coagulation factor fusion proteins expressed in chloroplasts of transgenic plants suppressed inhibitor formation directed against factors VIII and IX and anaphylaxis against factor IX (FIX). This observation and the relatively high concentration of antigen in the chloroplasts prompted us to evaluate the underlying tolerance mechanisms. The combination of oral delivery of bioencapsulated FIX and intravenous replacement therapy induced a complex, interleukin-10 (IL-10)-dependent, antigen-specific systemic immune suppression of pathogenic antibody formation (immunoglobulin [Ig] 1/inhibitors, IgE) in hemophilia B mice. Tolerance induction was also successful in preimmune mice but required prolonged oral delivery once replacement therapy was resumed. Orally delivered antigen, initially targeted to epithelial cells, was taken up by dendritic cells throughout the small intestine and additionally by F4/80(+) cells in the duodenum. Consistent with the immunomodulatory responses, frequencies of tolerogenic CD103(+) and plasmacytoid dendritic cells were increased. Ultimately, latency-associated peptide expressing CD4(+) regulatory T cells (CD4(+)CD25(-)LAP(+) cells with upregulated IL-10 and transforming growth factor-β (TGF-β) expression) as well as conventional CD4(+)CD25(+) regulatory T cells systemically suppressed anti-FIX responses. © 2015 by The American Society of Hematology.

  10. Notification: Implementation of Executive Order 13771, “Reducing Regulation and Controlling Regulatory Costs”

    Science.gov (United States)

    Project #OA&E-FY18-0177, April 10, 2018. The OIG plans to begin preliminary research on the Office of the Administrator's Office of Policy implementation of Executive Order 13771, Reducing Regulation and Controlling Regulatory Costs.

  11. Adaptive Observer-Based Fault-Tolerant Control Design for Uncertain Systems

    Directory of Open Access Journals (Sweden)

    Huaming Qian

    2015-01-01

    Full Text Available This study focuses on the design of the robust fault-tolerant control (FTC system based on adaptive observer for uncertain linear time invariant (LTI systems. In order to improve robustness, rapidity, and accuracy of traditional fault estimation algorithm, an adaptive fault estimation algorithm (AFEA using an augmented observer is presented. By utilizing a new fault estimator model, an improved AFEA based on linear matrix inequality (LMI technique is proposed to increase the performance. Furthermore, an observer-based state feedback fault-tolerant control strategy is designed, which guarantees the stability and performance of the faulty system. Moreover, the adaptive observer and the fault-tolerant controller are designed separately, whose performance can be considered, respectively. Finally, simulation results of an aircraft application are presented to illustrate the effectiveness of the proposed design methods.

  12. Continuous improvement of the regulatory framework for the control of medical exposure

    International Nuclear Information System (INIS)

    Larcher, Ana M.; Ortiz Lopez, Pedro; Arias, Cesar; Marechal, Maria H.; Hernandez Alvarez, Ramon; Ferrer Garcia, Natividad; Castaneda Mucino, Antonia; Faller, Blanca

    2008-01-01

    One of the key elements to guide the improvement of the regulatory control is the availability of a self-assessment tool for regulatory performance. Although there is general guidance on self-assessment for regulators and users (IAEA), there is a need for more specific advice on how to address challenges and difficulties faced by regulatory bodies, when regulating radiation protection of patients. Examples of these challenges are the need for regulatory initiatives, in cooperation with health and education authorities, professional bodies and equipment suppliers, and to put in place necessary elements that are beyond responsibility of individual user of radiation, to enable them compliance with safety standards. Purpose: Within the programme of the Ibero American Forum of Nuclear and Radiation Safety Regulatory Organizations, a project to develop such a self-assessment tool for the regulatory control of medical exposure has been designed. Method: National experiences in transposing and enforcing the international radiation safety standards, as to how the requirements are included in national regulations are reviewed. Further, difficulties to the implementation of safety requirements are analyzed and a self-assessment approach and possible regulatory solutions a are presented. Results and discussion: In this study the following documents are being produced: 1) transposition of international requirements into national regulations in the six countries of the Forum, 2) difficulties to implement and enforce the requirements, 3) guidance on self-assessment of regulatory framework for medical exposure, 4) suggested contribution to the revision of international radiation safety standards. (author)

  13. Continuous Improvement of the Regulatory Framework for the Control of Medical Exposure

    International Nuclear Information System (INIS)

    Larcher, A.M.; Ortiz lopez, Pedro; Arias, Cesar; Marechal, Maria H.; Hernandez Alvarez, Ramon; Ferrer Garcia, Natividad; Castaneda Mucino, Antonia; Faller, Blanca

    2011-01-01

    Background: One of the key elements to guide the improvement of the regulatory control is the availability of a self-assessment tool for regulatory performance. Although there is general guidance on self-assessment for regulators and users (IAEA), there is a need for specific advice on how to address challenges and difficulties faced by regulatory bodies, when regulating radiation protection of patients. Examples of these challenges are the need of regulatory initiatives, in cooperation with health and education authorities, professional bodies and equipment suppliers, and to put in place necessary elements that are beyond responsibility of individual users of radiation, to enable them compliance with safety standards. Purpose: within the programme of the Ibero American Forum of Nuclear and Radiation Safety Regulatory Organizations, a project to develop such a self assessment tool for the regulatory control of medical exposure has been designed. Method: national experiences in transposing and enforcing the international radiation safety standards, as to how the requirements are included in national regulations are reviewed. Further, difficulties to the implementation of safety requirements are included in national regulations are analyzed and a self assessment approach and possible regulatory solutions are presented. Results and discussion: in tis study the following documents are being produced: 1) Transposition of international requirements into national regulations in the six countries of the Forum, 2) difficulties to implement and enforce the requirements, 3) guidance on self assessment of regulatory framework for medical exposure, 4) suggested contribution to the revision of international radiation safety standards. (authors)

  14. Active fault tolerant control of piecewise affine systems with reference tracking and input constraints

    DEFF Research Database (Denmark)

    Gholami, M.; Cocquempot, V.; Schiøler, H.

    2014-01-01

    An active fault tolerant control (AFTC) method is proposed for discrete-time piecewise affine (PWA) systems. Only actuator faults are considered. The AFTC framework contains a supervisory scheme, which selects a suitable controller in a set of controllers such that the stability and an acceptable...... performance of the faulty system are held. The design of the supervisory scheme is not considered here. The set of controllers is composed of a normal controller for the fault-free case, an active fault detection and isolation controller for isolation and identification of the faults, and a set of passive...... fault tolerant controllers (PFTCs) modules designed to be robust against a set of actuator faults. In this research, the piecewise nonlinear model is approximated by a PWA system. The PFTCs are state feedback laws. Each one is robust against a fixed set of actuator faults and is able to track...

  15. Animal models of allergen-induced tolerance in asthma: are T-regulatory-1 cells (Tr-1) the solution for T-helper-2 cells (Th-2) in asthma?

    Science.gov (United States)

    Tournoy, K G; Hove, C; Grooten, J; Moerloose, K; Brusselle, G G; Joos, G F

    2006-01-01

    Non-specific anti-inflammatory medication is actually the treatment of choice for controlling the T-helper type 2 (Th-2) cell-driven airway inflammation in asthma. The induction of counterbalancing Th-1 cell clones, long considered a promising approach for immunotherapy, has failed to fulfil its promise because of potentially detrimental side-effects. This is therefore probably not a valid option for the treatment of asthma. With the increasing awareness that active immune mechanisms exist to control inflammatory responses, interest rises to investigate whether these can be exploited to control allergen-induced airway disease. The induction of antigen-specific T cells with suppressive characteristics (regulatory T cells) is therefore a potentially interesting approach. These regulatory T cells mediate tolerance in healthy, non-atopic individuals and have the potential of becoming an effective means of preventing allergen-induced airway inflammation and possibly of suppressing ongoing allergic immune responses. Here we review the available knowledge about allergen-induced suppressive immunity obtained from animal models taking into account the different developmental stages of allergic airway disease.

  16. Technical and regulatory challenges for digital instrumentation and control and control room systems in nuclear plants

    International Nuclear Information System (INIS)

    Torok, R.; Naser, J.; Harris, T.; Keithline, K.

    2006-01-01

    There are several unsettled technical and licensing issues in the areas of instrumentation and control (I and C), human factors, and updated control room designs that need coordinated, proactive industry attention. Some of these issues are already causing protracted regulatory reviews for existing plants, and left untreated, may cause substantial delays and increased costs for new plant combined construction and operating license approvals. Both industry and the NRC will have roles in resolving the key issues and addressing them in future design efforts and regulatory reviews. Where action is needed, the industry will want to minimize costs and risks by defining industry consensus solutions with corresponding technical bases. NEI has formed a working group to coordinate industry efforts and communications with NRC staff. The working group will also help determine priorities and coordinate both new and existing plant resources. EPRI will provide technical input and guidance for the working group. In order to be able to conduct reviews in a timely fashion, the NRC will likely need to enhance and expand staff resources as existing plants are upgraded and new plant reviews become more active. The industry initiative began with a workshop sponsored by EPRI and NEI on March 28-29, 2006, which led to the creation of the NEI working group. The working group has now identified and prioritized important generic issues, established resolution paths and schedules, and identified the roles of various stakeholders including utility companies, EPRI, NEI, vendors and the NRC. Through the course of this initiative I and C issues for both existing and new plants are being addressed. This paper describes the key I and C related technical and regulatory issues and their implications for new and operating plants, and provides a status report on the efforts to resolve them. (authors)

  17. Induction of Foxp3-expressing regulatory T-cells by donor blood transfusion is required for tolerance to rat liver allografts.

    Directory of Open Access Journals (Sweden)

    Yuta Abe

    Full Text Available BACKGROUND: Donor-specific blood transfusion (DST prior to solid organ transplantation has been shown to induce long-term allograft survival in the absence of immunosuppressive therapy. Although the mechanisms underlying DST-induced allograft tolerance are not well defined, there is evidence to suggest DST induces one or more populations of antigen-specific regulatory cells that suppress allograft rejection. However, neither the identity nor the regulatory properties of these tolerogenic lymphocytes have been reported. Therefore, the objective of this study was to define the kinetics, phenotype and suppressive function of the regulatory cells induced by DST alone or in combination with liver allograft transplantation (LTx. METHODOLOGY/PRINCIPAL FINDINGS: Tolerance to Dark Agouti (DA; RT1(a rat liver allografts was induced by injection (iv of 1 ml of heparinized DA blood to naïve Lewis (LEW; RT1(l rats once per week for 4 weeks prior to LTx. We found that preoperative DST alone generates CD4(+ T-cells that when transferred into naïve LEW recipients are capable of suppressing DA liver allograft rejection and promoting long-term survival of the graft and recipient. However, these DST-generated T-cells did not express the regulatory T-cell (Treg transcription factor Foxp3 nor did they suppress alloantigen (DA-induced activation of LEW T-cells in vitro suggesting that these lymphocytes are not fully functional regulatory Tregs. We did observe that DST+LTx (but not DST alone induced the time-dependent formation of CD4(+Foxp3(+ Tregs that potently suppressed alloantigen-induced activation of naïve LEW T-cells in vitro and liver allograft rejection in vivo. Finally, we present data demonstrating that virtually all of the Foxp3-expressing Tregs reside within the CD4(+CD45RC(- population whereas in which approximately 50% of these Tregs express CD25. CONCLUSIONS/SIGNIFICANCE: We conclude that preoperative DST, in the absence of liver allograft

  18. Implication of altered autonomic control for orthostatic tolerance in SCI.

    Science.gov (United States)

    Wecht, Jill Maria; Bauman, William A

    2018-01-01

    Neural output from the sympathetic and parasympathetic branches of the autonomic nervous system (ANS) are integrated to appropriately control cardiovascular responses during routine activities of daily living including orthostatic positioning. Sympathetic control of the upper extremity vasculature and the heart arises from the thoracic cord between T1 and T5, whereas splanchnic bed and lower extremity vasculature receive sympathetic neural input from the lower cord between segments T5 and L2. Although the vasculature is not directly innervated by the parasympathetic nervous system, the SA node is innervated by post-ganglionic vagal nerve fibers via cranial nerve X. Segmental differences in sympathetic cardiovascular innervation highlight the effect of lesion level on orthostatic cardiovascular control following spinal cord injury (SCI). Due to impaired sympathetic cardiovascular control, many individuals with SCI, particularly those with lesions above T6, are prone to orthostatic hypotension (OH) and orthostatic intolerance (OI). Symptomatic OH, which may result in OI, is a consequence of episodic reductions in cerebral perfusion pressure and the symptoms may include: dizziness, lightheadedness, nausea, blurred vision, ringing in the ears, headache and syncope. However, many, if not most, individuals with SCI who experience persistent and episodic hypotension and OH do not report symptoms of cerebral hypoperfusion and therefore do not raise clinical concern. This review will discuss the mechanism underlying OH and OI following SCI, and will review our knowledge to date regarding the prevalence, consequences and possible treatment options for these conditions in the SCI population. Published by Elsevier B.V.

  19. Fault Tolerant Emergency Control to Preserve Power System Stability

    DEFF Research Database (Denmark)

    Pedersen, Andreas Søndergaard; Richter, Jan H.; Tabatabaeipour, Mojtaba

    2016-01-01

    This paper introduces a method for fault-masking and system reconfiguration in power transmission systems. The paper demonstrates how faults are handled by reconfiguring remaining controls through utilisation of wide-area measurement in real time. It is shown how reconfiguration can be obtained u...

  20. A fault tolerant superheat control strategy for supermarket refrigeration systems

    DEFF Research Database (Denmark)

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

    2013-01-01

    , based on a maximum slope-seeking control method and only a single temperature sensor, is developed to drive the evaporator outlet temperature to a level that gives a suitable superheat of the refrigerant. The FTC strategy requires no a priori system knowledge or additional hardware and functions...

  1. Fault tolerant computer control for a Maglev transportation system

    Science.gov (United States)

    Lala, Jaynarayan H.; Nagle, Gail A.; Anagnostopoulos, George

    1994-01-01

    Magnetically levitated (Maglev) vehicles operating on dedicated guideways at speeds of 500 km/hr are an emerging transportation alternative to short-haul air and high-speed rail. They have the potential to offer a service significantly more dependable than air and with less operating cost than both air and high-speed rail. Maglev transportation derives these benefits by using magnetic forces to suspend a vehicle 8 to 200 mm above the guideway. Magnetic forces are also used for propulsion and guidance. The combination of high speed, short headways, stringent ride quality requirements, and a distributed offboard propulsion system necessitates high levels of automation for the Maglev control and operation. Very high levels of safety and availability will be required for the Maglev control system. This paper describes the mission scenario, functional requirements, and dependability and performance requirements of the Maglev command, control, and communications system. A distributed hierarchical architecture consisting of vehicle on-board computers, wayside zone computers, a central computer facility, and communication links between these entities was synthesized to meet the functional and dependability requirements on the maglev. Two variations of the basic architecture are described: the Smart Vehicle Architecture (SVA) and the Zone Control Architecture (ZCA). Preliminary dependability modeling results are also presented.

  2. Development of fault tolerant adaptive control laws for aerospace systems

    Science.gov (United States)

    Perez Rocha, Andres E.

    The main topic of this dissertation is the design, development and implementation of intelligent adaptive control techniques designed to maintain healthy performance of aerospace systems subjected to malfunctions, external parameter changes and/or unmodeled dynamics. The dissertation is focused on the development of novel adaptive control configurations that rely on non-linear functions that appear in the immune system of living organisms as main source of adaptation. One of the main goals of this dissertation is to demonstrate that these novel adaptive control architectures are able to improve overall performance and protect the system while reducing control effort and maintaining adequate operation outside bounds of nominal design. This research effort explores several phases, ranging from theoretical stability analysis, simulation and hardware implementation on different types of aerospace systems including spacecraft, aircraft and quadrotor vehicles. The results presented in this dissertation are focused on two main adaptivity approaches, the first one is intended for aerospace systems that do not attain large angles and use exact feedback linearization of Euler angle kinematics. A proof of stability is presented by means of the circle Criterion and Lyapunov's direct method. The second approach is intended for aerospace systems that can attain large attitude angles (e.g. space systems in gravity-less environments), the adaptation is incorporated on a baseline architecture that uses partial feedback linearization of quaternions kinematics. In this case, the closed loop stability was analyzed using Lyapunov's direct method and Barbalat's Lemma. It is expected that some results presented in this dissertation can contribute towards the validation and certification of direct adaptive controllers.

  3. Advanced I&C for Fault-Tolerant Supervisory Control of Small Modular Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Daniel G. [Univ. of Pittsburgh, PA (United States)

    2018-01-30

    In this research, we have developed a supervisory control approach to enable automated control of SMRs. By design the supervisory control system has an hierarchical, interconnected, adaptive control architecture. A considerable advantage to this architecture is that it allows subsystems to communicate at different/finer granularity, facilitates monitoring of process at the modular and plant levels, and enables supervisory control. We have investigated the deployment of automation, monitoring, and data collection technologies to enable operation of multiple SMRs. Each unit's controller collects and transfers information from local loops and optimize that unit’s parameters. Information is passed from the each SMR unit controller to the supervisory controller, which supervises the actions of SMR units and manage plant processes. The information processed at the supervisory level will provide operators the necessary information needed for reactor, unit, and plant operation. In conjunction with the supervisory effort, we have investigated techniques for fault-tolerant networks, over which information is transmitted between local loops and the supervisory controller to maintain a safe level of operational normalcy in the presence of anomalies. The fault-tolerance of the supervisory control architecture, the network that supports it, and the impact of fault-tolerance on multi-unit SMR plant control has been a second focus of this research. To this end, we have investigated the deployment of advanced automation, monitoring, and data collection and communications technologies to enable operation of multiple SMRs. We have created a fault-tolerant multi-unit SMR supervisory controller that collects and transfers information from local loops, supervise their actions, and adaptively optimize the controller parameters. The goal of this research has been to develop the methodologies and procedures for fault-tolerant supervisory control of small modular reactors. To achieve

  4. A Fault Tolerant Direct Control Allocation Scheme with Integral Sliding Modes

    Directory of Open Access Journals (Sweden)

    Hamayun Mirza Tariq

    2015-03-01

    Full Text Available In this paper, integral sliding mode control ideas are combined with direct control allocation in order to create a fault tolerant control scheme. Traditional integral sliding mode control can directly handle actuator faults; however, it cannot do so with actuator failures. Therefore, a mechanism needs to be adopted to distribute the control effort amongst the remaining functioning actuators in cases of faults or failures, so that an acceptable level of closed-loop performance can be retained. This paper considers the possibility of introducing fault tolerance even if fault or failure information is not provided to the control strategy. To demonstrate the efficacy of the proposed scheme, a high fidelity nonlinear model of a large civil aircraft is considered in the simulations in the presence of wind, gusts and sensor noise.

  5. Fault-tolerant control for current sensors of doubly fed induction generators based on an improved fault detection method

    DEFF Research Database (Denmark)

    Li, Hui; Yang, Chao; Hu, Yaogang

    2014-01-01

    Fault-tolerant control of current sensors is studied in this paper to improve the reliability of a doubly fed induction generator (DFIG). A fault-tolerant control system of current sensors is presented for the DFIG, which consists of a new current observer and an improved current sensor fault...... detection algorithm, and fault-tolerant control system are investigated by simulation. The results indicate that the outputs of the observer and the sensor are highly coherent. The fault detection algorithm can efficiently detect both soft and hard faults in current sensors, and the fault-tolerant control...

  6. Enhanced Maritime Safety through Diagnosis and Fault Tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens

    2001-01-01

    Faults in steering, navigation instruments or propulsion machinery are serious on a marine vessel since the consequence could be loss of maneuvering ability, and imply risk of damage to vessel personnel or environment. Early diagnosis and accomodation of faults could enhance safety. Fault...... of properties of a falty system; means to determine remedial actions. The paper illustrates the techniques by two marine examples, sensor fusion for automatic steering and control of the main engine....

  7. Sliding Mode Fault Tolerant Control with Adaptive Diagnosis for Aircraft Engines

    Science.gov (United States)

    Xiao, Lingfei; Du, Yanbin; Hu, Jixiang; Jiang, Bin

    2018-03-01

    In this paper, a novel sliding mode fault tolerant control method is presented for aircraft engine systems with uncertainties and disturbances on the basis of adaptive diagnostic observer. By taking both sensors faults and actuators faults into account, the general model of aircraft engine control systems which is subjected to uncertainties and disturbances, is considered. Then, the corresponding augmented dynamic model is established in order to facilitate the fault diagnosis and fault tolerant controller design. Next, a suitable detection observer is designed to detect the faults effectively. Through creating an adaptive diagnostic observer and based on sliding mode strategy, the sliding mode fault tolerant controller is constructed. Robust stabilization is discussed and the closed-loop system can be stabilized robustly. It is also proven that the adaptive diagnostic observer output errors and the estimations of faults converge to a set exponentially, and the converge rate greater than some value which can be adjusted by choosing designable parameters properly. The simulation on a twin-shaft aircraft engine verifies the applicability of the proposed fault tolerant control method.

  8. Balancing regulatory control, scientific knowledge, and public understanding.

    Science.gov (United States)

    Kingsbury, D T

    1988-01-01

    In summary, I would like to emphasize the continued need for broad and vigorous basic research, with a balance between the fundamental work that may eventually lead to commercial products and the fundamental work that is necessary for an understanding of the interaction of many types of organisms within the environment. I would like also to reiterate the need for balance in the regulatory approach so that we do not repress innovation in research and development. Over-regulation has many side effects. In addition to repressing innovation and not taking advantage of our research base, over-regulation leads to reluctance by the capital markets to invest in the future of our new industries, thereby halting their development at an early stage. At the same time, under-regulation leads to lack of confidence by the public and paralysis of the industry based on public outcry and legal proceedings. It is my personal belief that the combination of a sound approach to regulatory practice, based on current scientific knowledge, combined with appropriate communication with the public regarding the new products, will lead to an exciting future for all sectors of industry that use the new biotechnology.

  9. Fault Tolerant and Optimal Control of Wind Turbines with Distributed High-Speed Generators

    Directory of Open Access Journals (Sweden)

    Urs Giger

    2017-01-01

    Full Text Available In this paper, the control scheme of a distributed high-speed generator system with a total amount of 12 generators and nominal generator speed of 7000 min − 1 is studied. Specifically, a fault tolerant control (FTC scheme is proposed to keep the turbine in operation in the presence of up to four simultaneous generator faults. The proposed controller structure consists of two layers: The upper layer is the baseline controller, which is separated into a partial load region with the generator torque as an actuating signal and the full-load operation region with the collective pitch angle as the other actuating signal. In addition, the lower layer is responsible for the fault diagnosis and FTC characteristics of the distributed generator drive train. The fault reconstruction and fault tolerant control strategy are tested in simulations with several actuator faults of different types.

  10. Fractal gene regulatory networks for robust locomotion control of modular robots

    DEFF Research Database (Denmark)

    Zahadat, Payam; Christensen, David Johan; Schultz, Ulrik Pagh

    2010-01-01

    Designing controllers for modular robots is difficult due to the distributed and dynamic nature of the robots. In this paper fractal gene regulatory networks are evolved to control modular robots in a distributed way. Experiments with different morphologies of modular robot are performed and the ......Designing controllers for modular robots is difficult due to the distributed and dynamic nature of the robots. In this paper fractal gene regulatory networks are evolved to control modular robots in a distributed way. Experiments with different morphologies of modular robot are performed...

  11. Implementation of fault tolerant control for modular multilevel converter using EtherCAT communication

    DEFF Research Database (Denmark)

    Burlacu, Paul Dan; Mathe, Laszlo; Rejas, Marcos

    2015-01-01

    Modular Multilevel Converter (MMC) is very promising technology this days. It offers fault tolerant capabilities and ensures high efficiency with low output voltage harmonic content which results in need for smaller filter size. A disadvantage of the system is that the control becomes more...

  12. Active and passive fault-tolerant LPV control of wind Turbines

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Esbensen, Thomas; Stoustrup, Jakob

    2010-01-01

    This paper addresses the design and comparison of active and passive fault-tolerant linear parameter-varying (LPV) controllers for wind turbines. The considered wind turbine plant model is characterized by parameter variations along the nominal operating trajectory and includes a model of an inci...

  13. Fault Diagnosis and Fault Tolerant Control with Application on a Wind Turbine Low Speed Shaft Encoder

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Sardi, Hector Eloy Sanchez; Escobet, Teressa

    2015-01-01

    tolerant control of wind turbines using a benchmark model. In this paper, the fault diagnosis scheme is improved and integrated with a fault accommodation scheme which enables and disables the individual pitch algorithm based on the fault detection. In this way, the blade and tower loads are not increased...

  14. Active Fault-Tolerant Control for Wind Turbine with Simultaneous Actuator and Sensor Faults

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2017-01-01

    Full Text Available The purpose of this paper is to show a novel fault-tolerant tracking control (FTC strategy with robust fault estimation and compensating for simultaneous actuator sensor faults. Based on the framework of fault-tolerant control, developing an FTC design method for wind turbines is a challenge and, thus, they can tolerate simultaneous pitch actuator and pitch sensor faults having bounded first time derivatives. The paper’s key contribution is proposing a descriptor sliding mode method, in which for establishing a novel augmented descriptor system, with which we can estimate the state of system and reconstruct fault by designing descriptor sliding mode observer, the paper introduces an auxiliary descriptor state vector composed by a system state vector, actuator fault vector, and sensor fault vector. By the optimized method of LMI, the conditions for stability that estimated error dynamics are set up to promote the determination of the parameters designed. With this estimation, and designing a fault-tolerant controller, the system’s stability can be maintained. The effectiveness of the design strategy is verified by implementing the controller in the National Renewable Energy Laboratory’s 5-MW nonlinear, high-fidelity wind turbine model (FAST and simulating it in MATLAB/Simulink.

  15. The regulatory control of radiation sources in Turkey

    International Nuclear Information System (INIS)

    Uslu, I.; Birol, E.

    2001-01-01

    In Turkey, the national competent authority for regulating activities involving radioactive sources is the Turkish Atomic Energy Authority, which implements the responsibility for the safety and security of radiation sources through its Radiation Health and Safety Department. The report describes the organization of the regulatory infrastructure for radiation safety in Turkey and, after a brief explanation of the current legal framework for such purpose, it refers to how the management of radiation sources is carried out and to the new provisions regarding radiation sources, including inspections of licensees and training on source safety. Finally, the report provides information on the Ikitelli radiological accident in Turkey and the current public concern about radiation sources after it happened. (author)

  16. Mammalian iron metabolism and its control by iron regulatory proteins☆

    Science.gov (United States)

    Anderson, Cole P.; Shen, Lacy; Eisenstein, Richard S.; Leibold, Elizabeth A.

    2013-01-01

    Cellular iron homeostasis is maintained by iron regulatory proteins 1 and 2 (IRP1 and IRP2). IRPs bind to iron-responsive elements (IREs) located in the untranslated regions of mRNAs encoding protein involved in iron uptake, storage, utilization and export. Over the past decade, significant progress has been made in understanding how IRPs are regulated by iron-dependent and iron-independent mechanisms and the pathological consequences of IRP2 deficiency in mice. The identification of novel IREs involved in diverse cellular pathways has revealed that the IRP–IRE network extends to processes other than iron homeostasis. A mechanistic understanding of IRP regulation will likely yield important insights into the basis of disorders of iron metabolism. This article is part of a Special Issue entitled: Cell Biology of Metals. PMID:22610083

  17. Regulatory B and T cell responses in patients with autoimmune thyroid disease and healthy controls

    DEFF Research Database (Denmark)

    Kristensen, Birte; Hegedüs, Laszlo

    2016-01-01

    ). HT is primarily a T-cell mediated disease, and whether B cells play a pathogenic role in the pathogenesis is still unclear. Both GD and HT are characterized by infiltration of the thyroid gland by self-reactive T cells and B cells. In the first paper of this thesis, the role of regulatory B cells...... (Bregs) and regulatory T cells (Tregs) were investigated in the context of GD and HT. First, we studied the role of the thyroid self-antigen, thyroglobulin (TG) in healthy donors. The self-antigen TG, but not the foreign recall antigen tetanus toxoid (TT), was able to induce interleukin 10 (IL-10......Autoimmune diseases occur due to faulty self-tolerance. Graves' disease (GD) and Hashimoto's thyroiditis (HT) are classic examples of organ-specific autoimmune diseases. GD is an auto-antibody-mediated disease where autoantibodies are produced against the thyroid stimulating hormone receptor (TSHR...

  18. Interrelation between results of individual dosimetric control and regulatory control in Cuba

    International Nuclear Information System (INIS)

    Diaz Bernal, E.D.; Jova Sed, L.A.; Capote Ferrera, E.; Lopez Bejerano, G.M.

    1997-01-01

    The increasing use of various applications of ionizing radiation in Cuba made it necessary to create a harmonic system of facilities that guarantees the radiological safety of radiation workers, the public and the environment. Therefore, in 1985 a Centre of Radiation Protection and Hygiene (CPHR) was created. Thereafter, in 1991, the regulatory function and the inspection of radiological and nuclear safety was assigned to the National Centre of Nuclear Safety. The introduction of this service has provided the regulatory body with a tool to control the existing situation with respect to registration and licensing. The results of the service in the period 1994-1996 and a comparison with previous years are given. The results obtained reflect that the system of supervision in general has guaranteed keeping levels of doses low. The dose values registered demonstrate the possibility to establish in the country as a does limit an annual average dose limit of 20 mSv which might rise to but shall on no account exceed 50 mSv per year without the need for costly investment and based on organizational measures

  19. A fault-tolerant strategy based on SMC for current-controlled converters

    Science.gov (United States)

    Azer, Peter M.; Marei, Mostafa I.; Sattar, Ahmed A.

    2018-05-01

    The sliding mode control (SMC) is used to control variable structure systems such as power electronics converters. This paper presents a fault-tolerant strategy based on the SMC for current-controlled AC-DC converters. The proposed SMC is based on three sliding surfaces for the three legs of the AC-DC converter. Two sliding surfaces are assigned to control the phase currents since the input three-phase currents are balanced. Hence, the third sliding surface is considered as an extra degree of freedom which is utilised to control the neutral voltage. This action is utilised to enhance the performance of the converter during open-switch faults. The proposed fault-tolerant strategy is based on allocating the sliding surface of the faulty leg to control the neutral voltage. Consequently, the current waveform is improved. The behaviour of the current-controlled converter during different types of open-switch faults is analysed. Double switch faults include three cases: two upper switch fault; upper and lower switch fault at different legs; and two switches of the same leg. The dynamic performance of the proposed system is evaluated during healthy and open-switch fault operations. Simulation results exhibit the various merits of the proposed SMC-based fault-tolerant strategy.

  20. Distributed Fault-Tolerant Control of Networked Uncertain Euler-Lagrange Systems Under Actuator Faults.

    Science.gov (United States)

    Chen, Gang; Song, Yongduan; Lewis, Frank L

    2016-05-03

    This paper investigates the distributed fault-tolerant control problem of networked Euler-Lagrange systems with actuator and communication link faults. An adaptive fault-tolerant cooperative control scheme is proposed to achieve the coordinated tracking control of networked uncertain Lagrange systems on a general directed communication topology, which contains a spanning tree with the root node being the active target system. The proposed algorithm is capable of compensating for the actuator bias fault, the partial loss of effectiveness actuation fault, the communication link fault, the model uncertainty, and the external disturbance simultaneously. The control scheme does not use any fault detection and isolation mechanism to detect, separate, and identify the actuator faults online, which largely reduces the online computation and expedites the responsiveness of the controller. To validate the effectiveness of the proposed method, a test-bed of multiple robot-arm cooperative control system is developed for real-time verification. Experiments on the networked robot-arms are conduced and the results confirm the benefits and the effectiveness of the proposed distributed fault-tolerant control algorithms.

  1. Fault-Tolerant Control Strategy for Steering Failures in Wheeled Planetary Rovers

    Directory of Open Access Journals (Sweden)

    Alexandre Carvalho Leite

    2012-01-01

    Full Text Available Fault-tolerant control design of wheeled planetary rovers is described. This paper covers all steps of the design process, from modeling/simulation to experimentation. A simplified contact model is used with a multibody simulation model and tuned to fit the experimental data. The nominal mode controller is designed to be stable and has its parameters optimized to improve tracking performance and cope with physical boundaries and actuator saturations. This controller was implemented in the real rover and validated experimentally. An impact analysis defines the repertory of faults to be handled. Failures in steering joints are chosen as fault modes; they combined six fault modes and a total of 63 possible configurations of these faults. The fault-tolerant controller is designed as a two-step procedure to provide alternative steering and reuse the nominal controller in a way that resembles a crab-like driving mode. Three fault modes are injected (one, two, and three failed steering joints in the real rover to evaluate the response of the nonreconfigured and reconfigured control systems in face of these faults. The experimental results justify our proposed fault-tolerant controller very satisfactorily. Additional concluding comments and an outlook summarize the lessons learned during the whole design process and foresee the next steps of the research.

  2. Cooperative Fault Tolerant Tracking Control for Multiagent Systems: An Intermediate Estimator-Based Approach.

    Science.gov (United States)

    Zhu, Jun-Wei; Yang, Guang-Hong; Zhang, Wen-An; Yu, Li

    2017-10-17

    This paper studies the observer based fault tolerant tracking control problem for linear multiagent systems with multiple faults and mismatched disturbances. A novel distributed intermediate estimator based fault tolerant tracking protocol is presented. The leader's input is nonzero and unavailable to the followers. By applying a projection technique, the mismatched disturbances are separated into matched and unmatched components. For each node, a tracking error system is established, for which an intermediate estimator driven by the relative output measurements is constructed to estimate the sensor faults and a combined signal of the leader's input, process faults, and matched disturbance component. Based on the estimation, a fault tolerant tracking protocol is designed to eliminate the effects of the combined signal. Besides, the effect of unmatched disturbance component can be attenuated by directly adjusting some specified parameters. Finally, a simulation example of aircraft demonstrates the effectiveness of the designed tracking protocol.This paper studies the observer based fault tolerant tracking control problem for linear multiagent systems with multiple faults and mismatched disturbances. A novel distributed intermediate estimator based fault tolerant tracking protocol is presented. The leader's input is nonzero and unavailable to the followers. By applying a projection technique, the mismatched disturbances are separated into matched and unmatched components. For each node, a tracking error system is established, for which an intermediate estimator driven by the relative output measurements is constructed to estimate the sensor faults and a combined signal of the leader's input, process faults, and matched disturbance component. Based on the estimation, a fault tolerant tracking protocol is designed to eliminate the effects of the combined signal. Besides, the effect of unmatched disturbance component can be attenuated by directly adjusting some

  3. Regulatory control of radiation sources and radioactive materials in Ireland

    International Nuclear Information System (INIS)

    McGarry, A.T.; Fenton, D.; O'Flaherty, T.

    2001-01-01

    The primary legislation governing safety in uses of ionizing radiation in Ireland is the Radiological Protection Act, 1991. This Act provided for the establishment in 1992 of the Radiological Protection Institute of Ireland, and gives the Institute the functions and powers which enable it to be the regulatory body for all matters relating to ionizing radiation. A Ministerial Order made under the Act in 2000 consolidates previous regulations and, in particular, provides for the implementation in Irish law of the 1996 European Union Directive which lays down basic safety standards for the protection of the health of workers and the general public against the dangers arising from ionizing radiation. Under the legislation, the custody, use and a number of other activities involving radioactive substances and irradiating apparatus require a licence issued by the Institute. Currently some 1260 licences are in force. Of these, some 850 are in respect of irradiating apparatus only and are issued principally to dentists and veterinary surgeons. The remaining licences involve sealed radiation sources and/or unsealed radioactive substances used in medicine, industry or education. A schedule attached to each licence fully lists the sealed sources to which the licence applies, and also the quantities of radioactive substances which may be acquired or held under the licence. It is an offence to dispose of, or otherwise relinquish possession of, any licensable material other than in accordance with terms and conditions of the licence. Disused sources are returned to the original supplier or, where this is not possible, stored under licence by the licensee who used them. Enforcement of the licensing provisions relies primarily on the programme of inspection of licensees, carried out by the Institute's inspectors. The Institute's Regulatory Service has a complement of four inspectors, one of whom is the Manager of the Service. The Manager reports to one of the Institute's Principal

  4. Unsolved problems in applying U.S. regulatory guides to control system equipment

    International Nuclear Information System (INIS)

    Stade, R.E.

    1978-01-01

    Two current problems encountered when designing control systems to the United States Regulatory Guide requirements are discussed. They are: 1) Level of surge voltages that should be specified when procuring solid state control and instrumentation systems and equipment. 2) The approach to be used qualifying equipment that must meet the aging requirements. (author)

  5. Stabilization of Continuous-Time Random Switching Systems via a Fault-Tolerant Controller

    Directory of Open Access Journals (Sweden)

    Guoliang Wang

    2017-01-01

    Full Text Available This paper focuses on the stabilization problem of continuous-time random switching systems via exploiting a fault-tolerant controller, where the dwell time of each subsystem consists of a fixed part and random part. It is known from the traditional design methods that the computational complexity of LMIs related to the quantity of fault combination is very large; particularly system dimension or amount of subsystems is large. In order to reduce the number of the used fault combinations, new sufficient LMI conditions for designing such a controller are established by a robust approach, which are fault-free and could be solved directly. Moreover, the fault-tolerant stabilization realized by a mode-independent controller is considered and suitably applied to a practical case without mode information. Finally, a numerical example is used to demonstrate the effectiveness and superiority of the proposed methods.

  6. Adaptive robust fault-tolerant control for linear MIMO systems with unmatched uncertainties

    Science.gov (United States)

    Zhang, Kangkang; Jiang, Bin; Yan, Xing-Gang; Mao, Zehui

    2017-10-01

    In this paper, two novel fault-tolerant control design approaches are proposed for linear MIMO systems with actuator additive faults, multiplicative faults and unmatched uncertainties. For time-varying multiplicative and additive faults, new adaptive laws and additive compensation functions are proposed. A set of conditions is developed such that the unmatched uncertainties are compensated by actuators in control. On the other hand, for unmatched uncertainties with their projection in unmatched space being not zero, based on a (vector) relative degree condition, additive functions are designed to compensate for the uncertainties from output channels in the presence of actuator faults. The developed fault-tolerant control schemes are applied to two aircraft systems to demonstrate the efficiency of the proposed approaches.

  7. Nuclear security recommendations on nuclear and other radioactive material out of regulatory control: Recommendations

    International Nuclear Information System (INIS)

    2011-01-01

    The purpose of this publication is to provide guidance to States in strengthening their nuclear security regimes, and thereby contributing to an effective global nuclear security framework, by providing: - Recommendations to States and their competent authorities on the establishment or improvement of the capabilities of their nuclear security regimes, for carrying out effective strategies to deter, detect and respond to a criminal act, or an unauthorized act, with nuclear security implications, involving nuclear or other radioactive material that is out of regulatory control; - Recommendations to States in support of international cooperation aimed at ensuring that any nuclear or other radioactive material that is out of regulatory control, whether originating from within the State or from outside that State, is placed under regulatory control and the alleged offenders are, as appropriate, prosecuted or extradited

  8. Authority defied: need for cognitive closure influences regulatory control when resisting authority.

    Science.gov (United States)

    Damen, Tom G E; van Leeuwen, Matthijs L; Dijksterhuis, Ap; van Baaren, Rick B

    2014-08-01

    The present studies examined whether differences in need for cognitive closure (NCC) were related to differences in regulatory control when confronted with authority. In two studies, levels of regulatory control were measured when participants resisted (Study 1; N = 46) or prepared to resist the influence attempt of an authority figure (Study 2; N = 50). Results showed that resisting the influence attempt from a high-authority figure was more depleting for participants higher in NCC compared to individuals lower in NCC. However, when they were given instructions and time to prepare the act of resistance, individuals high in NCC actually showed an increase in regulatory control. Authority is usually viewed as a general principle of influence; however, the present studies suggest that there are individual differences that influence how people may experience interactions with authorities. © 2013 Wiley Periodicals, Inc.

  9. Schedule-controlled learning and memory in a regulatory context

    Science.gov (United States)

    Control of behavior by the manipulation of contingencies provides powerful techniques for assessing the hazard of chemical toxicants on the nervous system. When applied to evaluate the consequences of developmental exposure, these techniques are well suited for characterizing per...

  10. The regulatory control of radiation sources in Australia -- The challenges of a federal system

    International Nuclear Information System (INIS)

    Loy, J.; Colgan, P.

    2001-01-01

    The report refers to the challenges that Australia is facing, as a federal nation having a Commonwealth Government and six States and two territories, in establishing appropriate regulatory control of radiation sources. Information on the national inventory of radiation sources and existing regulatory infrastructure, including the system of notification, registration, licensing, inspection and enforcement, is explained in the report. The national provisions for the management of disused sources; the planning, preparedness and response to abnormal events and emergencies; the recovery of control over orphan sources; and education and training; are specifically emphasized. (author)

  11. Dynamic Output Feedback Based Active Decentralized Fault-Tolerant Control for Reconfigurable Manipulator with Concurrent Failures

    Directory of Open Access Journals (Sweden)

    Yuanchun Li

    2015-01-01

    Full Text Available The goal of this paper is to describe an active decentralized fault-tolerant control (ADFTC strategy based on dynamic output feedback for reconfigurable manipulators with concurrent actuator and sensor failures. Consider each joint module of the reconfigurable manipulator as a subsystem, and treat the fault as the unknown input of the subsystem. Firstly, by virtue of linear matrix inequality (LMI technique, the decentralized proportional-integral observer (DPIO is designed to estimate and compensate the sensor fault online; hereafter, the compensated system model could be derived. Then, the actuator fault is estimated similarly by another DPIO using LMI as well, and the sufficient condition of the existence of H∞ fault-tolerant controller in the dynamic output feedback is presented for the compensated system model. Furthermore, the dynamic output feedback controller is presented based on the estimation of actuator fault to realize active fault-tolerant control. Finally, two 3-DOF reconfigurable manipulators with different configurations are employed to verify the effectiveness of the proposed scheme in simulation. The main advantages of the proposed scheme lie in that it can handle the concurrent faults act on the actuator and sensor on the same joint module, as well as there is no requirement of fault detection and isolation process; moreover, it is more feasible to the modularity of the reconfigurable manipulator.

  12. Stochastic Model Predictive Fault Tolerant Control Based on Conditional Value at Risk for Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Yun-Tao Shi

    2018-01-01

    Full Text Available Wind energy has been drawing considerable attention in recent years. However, due to the random nature of wind and high failure rate of wind energy conversion systems (WECSs, how to implement fault-tolerant WECS control is becoming a significant issue. This paper addresses the fault-tolerant control problem of a WECS with a probable actuator fault. A new stochastic model predictive control (SMPC fault-tolerant controller with the Conditional Value at Risk (CVaR objective function is proposed in this paper. First, the Markov jump linear model is used to describe the WECS dynamics, which are affected by many stochastic factors, like the wind. The Markov jump linear model can precisely model the random WECS properties. Second, the scenario-based SMPC is used as the controller to address the control problem of the WECS. With this controller, all the possible realizations of the disturbance in prediction horizon are enumerated by scenario trees so that an uncertain SMPC problem can be transformed into a deterministic model predictive control (MPC problem. Finally, the CVaR object function is adopted to improve the fault-tolerant control performance of the SMPC controller. CVaR can provide a balance between the performance and random failure risks of the system. The Min-Max performance index is introduced to compare the fault-tolerant control performance with the proposed controller. The comparison results show that the proposed method has better fault-tolerant control performance.

  13. Optimal fault-tolerant control strategy of a solid oxide fuel cell system

    Science.gov (United States)

    Wu, Xiaojuan; Gao, Danhui

    2017-10-01

    For solid oxide fuel cell (SOFC) development, load tracking, heat management, air excess ratio constraint, high efficiency, low cost and fault diagnosis are six key issues. However, no literature studies the control techniques combining optimization and fault diagnosis for the SOFC system. An optimal fault-tolerant control strategy is presented in this paper, which involves four parts: a fault diagnosis module, a switching module, two backup optimizers and a controller loop. The fault diagnosis part is presented to identify the SOFC current fault type, and the switching module is used to select the appropriate backup optimizer based on the diagnosis result. NSGA-II and TOPSIS are employed to design the two backup optimizers under normal and air compressor fault states. PID algorithm is proposed to design the control loop, which includes a power tracking controller, an anode inlet temperature controller, a cathode inlet temperature controller and an air excess ratio controller. The simulation results show the proposed optimal fault-tolerant control method can track the power, temperature and air excess ratio at the desired values, simultaneously achieving the maximum efficiency and the minimum unit cost in the case of SOFC normal and even in the air compressor fault.

  14. Regulatory control of radioactive sources: an international perspective

    International Nuclear Information System (INIS)

    Flakus, F.N.

    1998-01-01

    Within its Regular Programme and its Technical Co-operation Programme, the IAEA undertakes a number of activities in support of national efforts aimed at strengthening national infrastructures for the control of radiation sources. The framework of these activities is described. (author)

  15. Design of passive fault-tolerant flight controller against actuator failures

    Directory of Open Access Journals (Sweden)

    Xiang Yu

    2015-02-01

    Full Text Available The problem of designing passive fault-tolerant flight controller is addressed when the normal and faulty cases are prescribed. First of all, the considered fault and fault-free cases are formed by polytopes. As considering that the safety of a post-fault system is directly related to the maximum values of physical variables in the system, peak-to-peak gain is selected to represent the relationships among the amplitudes of actuator outputs, system outputs, and reference commands. Based on the parameter dependent Lyapunov and slack methods, the passive fault-tolerant flight controllers in the absence/presence of system uncertainty for actuator failure cases are designed, respectively. Case studies of an airplane under actuator failures are carried out to validate the effectiveness of the proposed approach.

  16. Distributed Interplanetary Delay/Disruption Tolerant Network (DTN) Monitor and Control System

    Science.gov (United States)

    Wang, Shin-Ywan

    2012-01-01

    The main purpose of Distributed interplanetary Delay Tolerant Network Monitor and Control System as a DTN system network management implementation in JPL is defined to provide methods and tools that can monitor the DTN operation status, detect and resolve DTN operation failures in some automated style while either space network or some heterogeneous network is infused with DTN capability. In this paper, "DTN Monitor and Control system in Deep Space Network (DSN)" exemplifies a case how DTN Monitor and Control system can be adapted into a space network as it is DTN enabled.

  17. 1985 seminar on power plant digital control and fault-tolerant microcomputers: proceedings

    International Nuclear Information System (INIS)

    Divakaruni, S.M.

    1986-09-01

    An EPRI Seminar to address Power Plant Digital Controls and Fault-Tolerant Microcomputers Technology was hosted by Arizona Public Service Company in Phoenix, Arizona on April 9-12, 1986. The attendees represented a broad spectrum of US and foreign utilities, architect and consulting firms, and NSSS and computer system hardware vendors. These proceedings contain the text of the formal presentations as well as the papers and slides used during the short courses offered

  18. Genetic control and regulatory mechanisms of succinoglycan and curdlan biosynthesis in genus Agrobacterium.

    Science.gov (United States)

    Wu, Dan; Li, Ang; Ma, Fang; Yang, Jixian; Xie, Yutong

    2016-07-01

    Agrobacterium is a genus of gram-negative bacteria that can produce several typical exopolysaccharides with commercial uses in the food and pharmaceutical fields. In particular, succinoglycan and curdlan, due to their good quality in high yield, have been employed on an industrial scale comparatively early. Exopolysaccharide biosynthesis is a multiple-step process controlled by different functional genes, and various environmental factors cause changes in exopolysaccharide biosynthesis through regulatory mechanisms. In this mini-review, we focus on the genetic control and regulatory mechanisms of succinoglycan and curdlan produced by Agrobacterium. Some key functional genes and regulatory mechanisms for exopolysaccharide biosynthesis are described, possessing a high potential for application in metabolic engineering to modify exopolysaccharide production and physicochemical properties. This review may contribute to the understanding of exopolysaccharide biosynthesis and exopolysaccharide modification by metabolic engineering methods in Agrobacterium.

  19. A balance of activity in brain control and reward systems predicts self-regulatory outcomes

    OpenAIRE

    Lopez, Richard B.; Chen, Pin-Hao A.; Huckins, Jeremy F.; Hofmann, Wilhelm; Kelley, William M.; Heatherton, Todd F.

    2017-01-01

    Abstract Previous neuroimaging work has shown that increased reward-related activity following exposure to food cues is predictive of self-control failure. The balance model suggests that self-regulation failures result from an imbalance in reward and executive control mechanisms. However, an open question is whether the relative balance of activity in brain systems associated with executive control (vs reward) supports self-regulatory outcomes when people encounter tempting cues in daily lif...

  20. Validation of gamma irradiator controls for quality and regulatory compliance

    International Nuclear Information System (INIS)

    Harding, R.B.; Pinteric, F.J.A.

    1995-01-01

    Since 1978 the U.S. Food and Drug Administration (FDA) has had both the legal authority and the current good manufacturing practice (CGMP) regulations in progress to require irradiator owners who process medical devices to produce evidence of Irradiation Process Validation. One of the key components of Irradiation Process Validation is the validation of the irradiator controls. However it is only recently that FDA audits have focussed on this component of the process validation. (author)

  1. Regulating the path from legacy recognition, through recovery to release from regulatory control.

    Science.gov (United States)

    Sneve, Malgorzata Karpow; Smith, Graham

    2015-04-01

    Past development of processes and technologies using radioactive material led to construction of many facilities worldwide. Some of these facilities were built and operated before the regulatory infrastructure was in place to ensure adequate control of radioactive material during operation and decommissioning. In other cases, controls were in place but did not meet modern standards, leading to what is now considered to have been inadequate control. Accidents and other events have occurred resulting in loss of control of radioactive material and unplanned releases to the environment. The legacy from these circumstances is that many countries have areas or facilities at which abnormal radiation conditions exist at levels that give rise to concerns about environmental and human health of potential interest to regulatory authorities. Regulation of these legacy situations is complex. This paper examines the regulatory challenges associated with such legacy management and brings forward suggestions for finding the path from: legacy recognition; implementation, as necessary, of urgent mitigation measures; development of a longer-term management strategy, through to release from regulatory control. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. The Design and Semi-Physical Simulation Test of Fault-Tolerant Controller for Aero Engine

    Science.gov (United States)

    Liu, Yuan; Zhang, Xin; Zhang, Tianhong

    2017-11-01

    A new fault-tolerant control method for aero engine is proposed, which can accurately diagnose the sensor fault by Kalman filter banks and reconstruct the signal by real-time on-board adaptive model combing with a simplified real-time model and an improved Kalman filter. In order to verify the feasibility of the method proposed, a semi-physical simulation experiment has been carried out. Besides the real I/O interfaces, controller hardware and the virtual plant model, semi-physical simulation system also contains real fuel system. Compared with the hardware-in-the-loop (HIL) simulation, semi-physical simulation system has a higher degree of confidence. In order to meet the needs of semi-physical simulation, a rapid prototyping controller with fault-tolerant control ability based on NI CompactRIO platform is designed and verified on the semi-physical simulation test platform. The result shows that the controller can realize the aero engine control safely and reliably with little influence on controller performance in the event of fault on sensor.

  3. Data-Reconciliation Based Fault-Tolerant Model Predictive Control for a Biomass Boiler

    Directory of Open Access Journals (Sweden)

    Palash Sarkar

    2017-02-01

    Full Text Available This paper presents a novel, effective method to handle critical sensor faults affecting a control system devised to operate a biomass boiler. In particular, the proposed method consists of integrating a data reconciliation algorithm in a model predictive control loop, so as to annihilate the effects of faults occurring in the sensor of the flue gas oxygen concentration, by feeding the controller with the reconciled measurements. Indeed, the oxygen content in flue gas is a key variable in control of biomass boilers due its close connections with both combustion efficiency and polluting emissions. The main benefit of including the data reconciliation algorithm in the loop, as a fault tolerant component, with respect to applying standard fault tolerant methods, is that controller reconfiguration is not required anymore, since the original controller operates on the restored, reliable data. The integrated data reconciliation–model predictive control (MPC strategy has been validated by running simulations on a specific type of biomass boiler—the KPA Unicon BioGrate boiler.

  4. Criteria of exemption of regulatory control for radioactive material; Criterios de exencion del control regulatorio para material radiactivo

    Energy Technology Data Exchange (ETDEWEB)

    Medrano Lopez, Marco A [Gerencia de Seguridad Radiologica, Instituto Nacional de Investigaciones Nucleares, Salazar (Mexico)

    1991-07-01

    Being based on the information contained in the 10 CFR Part 20, of the section 20.301 until the 20.306 where the mechanisms by means of which can prepare the waste of low level are indicated. While the Nuclear Regulatory Commission (NRC) it amended in the year of 1985 the Act of Politics on Low level Wastes, in particular the section 10 of the amendment of the Act, relative to the concept BRC treats those groups of radioactive waste in that their activity contents are so low that they could be exempt of the regulatory control, either liberating them toward the environment or to exempt people or organizations of the regulatory control.

  5. THE ROLE OF SELF-REGULATORY AUDITING ASSOCIATIONS IN ARRANGEMENT OF AUDIT ACTIVITIES QUALITY CONTROL

    Directory of Open Access Journals (Sweden)

    Zinaida P. Arharova

    2013-01-01

    Full Text Available The role of self-regulatory organizations in audit activities quality control is revealed in this article. Creation of a united audit association is the basis of certain regulating and auditing functions transfer from the government to the public sector.

  6. Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

    International Nuclear Information System (INIS)

    1997-11-01

    The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference

  7. Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference. Refs, figs, tabs.

  8. An overview of exhaust emissions regulatory requirements and control technology for stationary natural gas engines

    International Nuclear Information System (INIS)

    Ballard, H.N.; Hay, S.C.; Shade, W.N. Jr.

    1992-01-01

    In this paper a practical overview of stationary natural gas engine exhaust emissions control technology and trends in emissions regulatory requirements is presented. Selective and non-selective catalytic reduction and lean burn technologies are compared. Particular emphasis is focussed on implications of the Clean Air Act of 1990. Recent emissions reduction conversion kit developments and a practical approach to continuous monitoring are discussed

  9. Enforcement of radiation safety standards and experience in the regulatory control of exposures

    Energy Technology Data Exchange (ETDEWEB)

    Krishnamurthi, T N [Health and Safety Div., Atomic Energy Regulatory Board, Mumbai (India)

    1997-11-01

    Regulatory provisions for radiation protection and their enforcement in India are discussed in this paper. The rules and regulations framed for radiation safety cover all the nuclear fuel cycle activities as well as the application of radiation sources in industrial, medical and research institutions. The enforcement aspects and experience in the control of exposures are presented. (author). 3 refs, 2 tabs.

  10. Enforcement of radiation safety standards and experience in the regulatory control of exposures

    International Nuclear Information System (INIS)

    Krishnamurthi, T.N.

    1997-01-01

    Regulatory provisions for radiation protection and their enforcement in India are discussed in this paper. The rules and regulations framed for radiation safety cover all the nuclear fuel cycle activities as well as the application of radiation sources in industrial, medical and research institutions. The enforcement aspects and experience in the control of exposures are presented. (author)

  11. International principles for exemption from regulatory control and their application to waste management

    International Nuclear Information System (INIS)

    Linsley, G.S.

    1989-01-01

    This paper describes the main features of the international consensus on principles for exempting radiation sources and practices from regulatory control reached at a meeting in Vienna in March 1988. Some remaining problems, both of a philosophical and technical nature especially related to the application of the principles to radioactive waste disposal, are discussed

  12. Neuroadaptive Fault-Tolerant Control of Nonlinear Systems Under Output Constraints and Actuation Faults.

    Science.gov (United States)

    Zhao, Kai; Song, Yongduan; Shen, Zhixi

    2018-02-01

    In this paper, a neuroadaptive fault-tolerant tracking control method is proposed for a class of time-delay pure-feedback systems in the presence of external disturbances and actuation faults. The proposed controller can achieve prescribed transient and steady-state performance, despite uncertain time delays and output constraints as well as actuation faults. By combining a tangent barrier Lyapunov-Krasovskii function with the dynamic surface control technique, the neural network unit in the developed control scheme is able to take its action from the very beginning and play its learning/approximating role safely during the entire system operational envelope, leading to enhanced control performance without the danger of violating compact set precondition. Furthermore, prescribed transient performance and output constraints are strictly ensured in the presence of nonaffine uncertainties, external disturbances, and undetectable actuation faults. The control strategy is also validated by numerical simulation.

  13. Orchestration of transplantation tolerance by regulatory dendritic cell therapy or in-situ targeting of dendritic cells.

    Science.gov (United States)

    Morelli, Adrian E; Thomson, Angus W

    2014-08-01

    Extensive research in murine transplant models over the past two decades has convincingly demonstrated the ability of regulatory dendritic cells (DCregs) to promote long-term allograft survival. We review important considerations regarding the source of therapeutic DCregs (donor or recipient) and their mode of action, in-situ targeting of DCregs, and optimal therapeutic regimens to promote DCreg function. Recent studies have defined protocols and mechanisms whereby ex-vivo-generated DCregs of donor or recipient origin subvert allogeneic T-cell responses and promote long-term organ transplant survival. Particular interest has focused on how donor antigen is acquired, processed and presented by autologous dendritic cells, on the stability of DCregs, and on in-situ targeting of dendritic cells to promote their tolerogenic function. New evidence of the therapeutic efficacy of DCregs in a clinically relevant nonhuman primate organ transplant model and production of clinical grade DCregs support early evaluation of DCreg therapy in human graft recipients. We discuss strategies currently used to promote dendritic cell tolerogenicity, including DCreg therapy and in-situ targeting of dendritic cells, with a view to improved understanding of underlying mechanisms and identification of the most promising strategies for therapeutic application.

  14. CEGB philosophy and experience with fault-tolerant micro-computer application for power plant controls

    International Nuclear Information System (INIS)

    Clinch, D.A.L.

    1986-01-01

    From the mid-1960s until the late 1970s, automatic modulating control of the main boiler plant on CEGB fossil-fired power stations was largely implemented with hard wired electronic equipment. Mid-way through this period, the CEGB formulated a set of design requirements for this type of equipment; these laid particular emphasis on the fault tolerance of a control system and specified the nature of the interfaces with a control desk and with plant regulators. However, the automatic control of an Advanced Gas Cooled Reactor (AGR) is based upon measured values which are derived by processing a large number of thermocouple signals. This is more readily implemented digitally than with hard-wired equipment. Essential to the operation of an AGR power station is a data processing (DP) computer for monitoring the plant; so the first group of AGR power stations, designed in the 1960s, employed their DP computers for modulating control. Since the late 1970s, automatic modulating control of major plants, for new power stations and for re-fits on established power stations, has been implemented with micro-computers. Wherever practicable, the policy formulated earlier for hard-wired equipment has been retained, particularly in respect of the interfaces. This policy forms the foundation of the fault tolerance of these micro-computer systems

  15. ALLIANCE: An architecture for fault tolerant, cooperative control of heterogeneous mobile robots

    Energy Technology Data Exchange (ETDEWEB)

    Parker, L.E.

    1995-02-01

    This research addresses the problem of achieving fault tolerant cooperation within small- to medium-sized teams of heterogeneous mobile robots. The author describes a novel behavior-based, fully distributed architecture, called ALLIANCE, that utilizes adaptive action selection to achieve fault tolerant cooperative control in robot missions involving loosely coupled, largely independent tasks. The robots in this architecture possess a variety of high-level functions that they can perform during a mission, and must at all times select an appropriate action based on the requirements of the mission, the activities of other robots, the current environmental conditions, and their own internal states. Since such cooperative teams often work in dynamic and unpredictable environments, the software architecture allows the team members to respond robustly and reliably to unexpected environmental changes and modifications in the robot team that may occur due to mechanical failure, the learning of new skills, or the addition or removal of robots from the team by human intervention. After presenting ALLIANCE, the author describes in detail experimental results of an implementation of this architecture on a team of physical mobile robots performing a cooperative box pushing demonstration. These experiments illustrate the ability of ALLIANCE to achieve adaptive, fault-tolerant cooperative control amidst dynamic changes in the capabilities of the robot team.

  16. The Regulatory Networks That Control Clostridium difficile Toxin Synthesis

    Science.gov (United States)

    Martin-Verstraete, Isabelle; Peltier, Johann; Dupuy, Bruno

    2016-01-01

    The pathogenic clostridia cause many human and animal diseases, which typically arise as a consequence of the production of potent exotoxins. Among the enterotoxic clostridia, Clostridium difficile is the main causative agent of nosocomial intestinal infections in adults with a compromised gut microbiota caused by antibiotic treatment. The symptoms of C. difficile infection are essentially caused by the production of two exotoxins: TcdA and TcdB. Moreover, for severe forms of disease, the spectrum of diseases caused by C. difficile has also been correlated to the levels of toxins that are produced during host infection. This observation strengthened the idea that the regulation of toxin synthesis is an important part of C. difficile pathogenesis. This review summarizes our current knowledge about the regulators and sigma factors that have been reported to control toxin gene expression in response to several environmental signals and stresses, including the availability of certain carbon sources and amino acids, or to signaling molecules, such as the autoinducing peptides of quorum sensing systems. The overlapping regulation of key metabolic pathways and toxin synthesis strongly suggests that toxin production is a complex response that is triggered by bacteria in response to particular states of nutrient availability during infection. PMID:27187475

  17. U.S. Nuclear Regulatory Commission bases for control of solid materials

    International Nuclear Information System (INIS)

    Meck, R.A.; Cardille, F.P.; Feldman, C.; Gnugnoli, G.N.; Huffert, A.M.; Klementowicz, S.P.

    2002-01-01

    The U.S. Nuclear Regulatory Commission (NRC) is considering whether to proceed with rulemaking on the control of solid materials with very low levels of associated radioactivity. The current implementation of clearance by NRC licensees is the context for the decision. Inputs to the decision include information gathering efforts of the Commission in the areas of public workshops, dose assessments and inventories, the recommendations of the National Academies' National Research Council (NAs) on regulatory alternatives, and participation in international efforts by the International Atomic Energy Agency (IAEA). (author)

  18. A Piecewise Affine Hybrid Systems Approach to Fault Tolerant Satellite Formation Control

    DEFF Research Database (Denmark)

    Grunnet, Jacob Deleuran; Larsen, Jesper Abildgaard; Bak, Thomas

    2008-01-01

    In this paper a procedure for modelling satellite formations   including failure dynamics as a piecewise-affine hybrid system is   shown. The formulation enables recently developed methods and tools   for control and analysis of piecewise-affine systems to be applied   leading to synthesis of fault...... tolerant controllers and analysis of   the system behaviour given possible faults.  The method is   illustrated using a simple example involving two satellites trying   to reach a specific formation despite of actuator faults occurring....

  19. Fault Diagnosis and Tolerant Control Using Observer Banks Applied to Continuous Stirred Tank Reactor

    Directory of Open Access Journals (Sweden)

    Martin F. Pico

    2017-04-01

    Full Text Available This paper focuses on studying the problem of fault tolerant control (FTC, including a detailed fault detection and diagnosis (FDD module using observer banks which consists of output and unknown input observers applied to a continuous stirred tank reactor (CSTR. The main objective of this paper is to use a FDD module here proposed to estimate the fault in order to apply this result in a FTC system (FTCS, to prevent a lost of of the control system performance. The benefits of the observer bank and fault adaptation here studied are illustrated by numerical simulations which assumes faults in manipulated and measuring elements of the CSTR.

  20. Association Between Cardiorespiratory Fitness and the Determinants of Glycemic Control Across the Entire Glucose Tolerance Continuum

    DEFF Research Database (Denmark)

    Solomon, Thomas P. J.; Malin, Steven K.; Karstoft, Kristian

    2015-01-01

    OBJECTIVE: Cardiorespiratory fitness (VO2max) is associated with glycemic control, yet the relationship between VO2max and the underlying determinants of glycemic control is less clear. Our aim was to determine whether VO2max is associated with insulin sensitivity, insulin secretion, and the disp...... fitness and compromised pancreatic β-cell compensation across the entire glucose tolerance continuum provides additional evidence highlighting the importance of fitness in protection against the onset of a fundamental pathophysiological event that leads to type 2 diabetes....

  1. The antianginal efficacy and tolerability of controlled-release metoprolol once daily

    DEFF Research Database (Denmark)

    Egstrup, K; Gundersen, T; Härkönen, R

    1988-01-01

    In a randomized, double-blind, cross-over study treatment with a new controlled-release (CR) preparation of metoprolol, given once daily, was compared with treatment with conventional metoprolol tablets, given twice daily, in 115 patients with stable effort angina pectoris. The patients were...... questionnaire. When all patients were analysed together there were no differences in antianginal efficacy between the two treatment regimens. However, when the group taking 200 mg daily was analysed separately better exercise tolerance was found during metoprolol CR therapy, as measured by onset of chest pain...... and ST-segment change, compared with conventional metoprolol therapy. The two formulations were well tolerated. When given once daily in a total daily dose of 100 mg, the CR preparation induced less adverse effects than the conventional tablets, 50 mg twice daily. It was concluded that the new metoprolol...

  2. Economic modeling of fault tolerant flight control systems in commercial applications

    Science.gov (United States)

    Finelli, G. B.

    1982-01-01

    This paper describes the current development of a comprehensive model which will supply the assessment and analysis capability to investigate the economic viability of Fault Tolerant Flight Control Systems (FTFCS) for commercial aircraft of the 1990's and beyond. An introduction to the unique attributes of fault tolerance and how they will influence aircraft operations and consequent airline costs and benefits is presented. Specific modeling issues and elements necessary for accurate assessment of all costs affected by ownership and operation of FTFCS are delineated. Trade-off factors are presented, aimed at exposing economically optimal realizations of system implementations, resource allocation, and operating policies. A trade-off example is furnished to graphically display some of the analysis capabilities of the comprehensive simulation model now being developed.

  3. Fault-Tolerant Region-Based Control of an Underwater Vehicle with Kinematically Redundant Thrusters

    Directory of Open Access Journals (Sweden)

    Zool H. Ismail

    2014-01-01

    Full Text Available This paper presents a new control approach for an underwater vehicle with a kinematically redundant thruster system. This control scheme is derived based on a fault-tolerant decomposition for thruster force allocation and a region control scheme for the tracking objective. Given a redundant thruster system, that is, six or more pairs of thrusters are used, the proposed redundancy resolution and region control scheme determine the number of thruster faults, as well as providing the reference thruster forces in order to keep the underwater vehicle within the desired region. The stability of the presented control law is proven in the sense of a Lyapunov function. Numerical simulations are performed with an omnidirectional underwater vehicle and the results of the proposed scheme illustrate the effectiveness in terms of optimizing the thruster forces.

  4. A hybrid robust fault tolerant control based on adaptive joint unscented Kalman filter.

    Science.gov (United States)

    Shabbouei Hagh, Yashar; Mohammadi Asl, Reza; Cocquempot, Vincent

    2017-01-01

    In this paper, a new hybrid robust fault tolerant control scheme is proposed. A robust H ∞ control law is used in non-faulty situation, while a Non-Singular Terminal Sliding Mode (NTSM) controller is activated as soon as an actuator fault is detected. Since a linear robust controller is designed, the system is first linearized through the feedback linearization method. To switch from one controller to the other, a fuzzy based switching system is used. An Adaptive Joint Unscented Kalman Filter (AJUKF) is used for fault detection and diagnosis. The proposed method is based on the simultaneous estimation of the system states and parameters. In order to show the efficiency of the proposed scheme, a simulated 3-DOF robotic manipulator is used. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Sliding observer-based demagnetisation fault-tolerant control in permanent magnet synchronous motors

    Directory of Open Access Journals (Sweden)

    Changfan Zhang

    2017-04-01

    Full Text Available This study proposes a fault-tolerant control method for permanent magnet synchronous motors (PMSMs based on the active flux linkage concept, which addresses permanent magnet (PM demagnetisation faults in PMSMs. First, a mathematical model for a PMSM is established based on active flux linkage, and then the effect of PM demagnetisation on the PMSM is analysed. Second, the stator current in the static coordinate is set as the state variable, an observer is designed based on a sliding-mode variable structure, and an equation for active flux linkage is established for dynamic estimation based on the equivalent control principle of sliding-mode variable structure. Finally, the active flux linkage for the next moment is predicted according to the operating conditions of the motor and the observed values of the current active flux linkage. The deadbeat control strategy is applied to eliminate errors in the active flux linkage and realise the objective of fault-tolerant control. A timely and effective control for demagnetisation faults is achieved using the proposed method, which validity and feasibility are verified by the simulation and experiment results.

  6. Adaptive extended-state observer-based fault tolerant attitude control for spacecraft with reaction wheels

    Science.gov (United States)

    Ran, Dechao; Chen, Xiaoqian; de Ruiter, Anton; Xiao, Bing

    2018-04-01

    This study presents an adaptive second-order sliding control scheme to solve the attitude fault tolerant control problem of spacecraft subject to system uncertainties, external disturbances and reaction wheel faults. A novel fast terminal sliding mode is preliminarily designed to guarantee that finite-time convergence of the attitude errors can be achieved globally. Based on this novel sliding mode, an adaptive second-order observer is then designed to reconstruct the system uncertainties and the actuator faults. One feature of the proposed observer is that the design of the observer does not necessitate any priori information of the upper bounds of the system uncertainties and the actuator faults. In view of the reconstructed information supplied by the designed observer, a second-order sliding mode controller is developed to accomplish attitude maneuvers with great robustness and precise tracking accuracy. Theoretical stability analysis proves that the designed fault tolerant control scheme can achieve finite-time stability of the closed-loop system, even in the presence of reaction wheel faults and system uncertainties. Numerical simulations are also presented to demonstrate the effectiveness and superiority of the proposed control scheme over existing methodologies.

  7. Regulatory B and T cell responses in patients with autoimmune thyroid disease and healthy controls

    DEFF Research Database (Denmark)

    Kristensen, Birte

    2016-01-01

    Autoimmune diseases occur due to faulty self-tolerance. Graves' disease (GD) and Hashimoto's thyroiditis (HT) are classic examples of organ-specific autoimmune diseases. GD is an auto-antibody-mediated disease where autoantibodies are produced against the thyroid stimulating hormone receptor (TSHR...... (Bregs) and regulatory T cells (Tregs) were investigated in the context of GD and HT. First, we studied the role of the thyroid self-antigen, thyroglobulin (TG) in healthy donors. The self-antigen TG, but not the foreign recall antigen tetanus toxoid (TT), was able to induce interleukin 10 (IL-10......) secretion by B cells and CD4+ T cells. These IL-10 producing B cells (B10 cells) from healthy donors were enriched with the CD5+ and CD24hi phenotype. In addition, TG was able to induce IL-6 production by B cells. In contrast, TT induced production of Th1-type pro-inflammatory cytokines including interferon...

  8. Mechanisms Controlling Species Responses to Climate Change: Thermal Tolerances and Shifting Range Limits. (Invited)

    Science.gov (United States)

    Sage, R. F.; Bykova, O.; Coiner, H.

    2010-12-01

    One of the main effects of anthropogenic climate change will be widespread shifts in species distribution, with the common assumption that they will migrate to higher elevation and latitude. While this assumption is supported by migration patterns following climate warming in the past 20,000 years, it has not been rigorously evaluated in terms of physiological mechanism, despite the implication that migration in response to climate warming is controlled by some form of thermal adaptation. We have been evaluating the degree to which species range limits are controlled by physiological patterns of thermal tolerance in bioinvaders of North America. Bioinvaders presumably have few biotic controls over their distribution and thus are more likely to fully exploit their thermal niche. In cheatgrass (Bromus tectorum), the minimum lethal temperature in winter is -32C, which corresponds to the mean winter minimum temperature at its northern range limit. In red brome (Bromus rubens), the minimum lethal temperature is also near -32C, which is well below the minimum winter temperature near -20C that corresponds to its northern distribution limit. In kudzu (Pueraria lobata), the minimum lethal temperature is near -20C, which corresponds to the midwinter minimum at its northern distribution limit; however, overwintering kudzu tissues are insulated by soil and snow cover, and thus do not experience lethal temperatures at kudzu's northern range limit. These results demonstrate that some invasive species can exploit the potential range defined by their low temperature tolerance and thus can be predicted by mechanistic models to migrate to higher latitudes with moderation of winter cold. The distribution of other invaders such as kudzu and red brome are not controlled by tolerance of midwinter cold. Developing mechanistic models of their distributions, and how these might change with climate warming, will require extensive physiological study.

  9. Design of neuro fuzzy fault tolerant control using an adaptive observer

    International Nuclear Information System (INIS)

    Anita, R.; Umamaheswari, B.; Viswanathan, B.

    2001-01-01

    New methodologies and concepts are developed in the control theory to meet the ever-increasing demands in industrial applications. Fault detection and diagnosis of technical processes have become important in the course of progressive automation in the operation of groups of electric drives. When a group of electric drives is under operation, fault tolerant control becomes complicated. For multiple motors in operation, fault detection and diagnosis might prove to be difficult. Estimation of all states and parameters of all drives is necessary to analyze the actuator and sensor faults. To maintain system reliability, detection and isolation of failures should be performed quickly and accurately, and hardware should be properly integrated. Luenberger full order observer can be used for estimation of the entire states in the system for the detection of actuator and sensor failures. Due to the insensitivity of the Luenberger observer to the system parameter variations, state estimation becomes inaccurate under the varying parameter conditions of the drives. Consequently, the estimation performance deteriorates, resulting in ordinary state observers unsuitable for fault detection technique. Therefore an adaptive observe, which can estimate the system states and parameter and detect the faults simultaneously, is designed in our paper. For a Group of D C drives, there may be parameter variations for some of the drives, and for other drives, there may not be parameter variations depending on load torque, friction, etc. So, estimation of all states and parameters of all drives is carried out using an adaptive observer. If there is any deviation with the estimated values, it is understood that fault has occurred and the nature of the fault, whether sensor fault or actuator fault, is determined by neural fuzzy network, and fault tolerant control is reconfigured. Experimental results with neuro fuzzy system using adaptive observer-based fault tolerant control are good, so as

  10. A Fault-tolerable Control Scheme for an Open-frame Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Huang Hai

    2014-05-01

    Full Text Available Open-frame is one of the major types of structures of Remote Operated Vehicles (ROV because it is easy to place sensors and operations equipment onboard. Firstly, this paper designed a petri-based recurrent neural network (PRFNN to improve the robustness with response to nonlinear characteristics and strong disturbance of an open-frame underwater vehicle. A threshold has been set in the third layer to reduce the amount of calculations and regulate the training process. The whole network convergence is guaranteed with the selection of learning rate parameters. Secondly, a fault tolerance control (FTC scheme is established with the optimal allocation of thrust. Infinity-norm optimization has been combined with 2-norm optimization to construct a bi-criteria primal-dual neural network FTC scheme. In the experiments and simulation, PRFNN outperformed fuzzy neural networks in motion control, while bi-criteria optimization outperformed 2-norm optimization in FTC, which demonstrates that the FTC controller can improve computational efficiency, reduce control errors, and implement fault tolerable thrust allocation.

  11. Engineering tolerance using biomaterials to target and control antigen presenting cells.

    Science.gov (United States)

    Tostanoski, Lisa H; Gosselin, Emily A; Jewell, Christopher M

    2016-05-01

    Autoimmune diseases occur when cells of the adaptive immune system incorrectly recognize and attack "self" tissues. Importantly, the proliferation and differentiation of these cells is triggered and controlled by interactions with antigen presenting cells (APCs), such as dendritic cells. Thus, modulating the signals transduced by APCs (e.g., cytokines, costimulatory surface proteins) has emerged as a promising strategy to promote tolerance for diseases such as multiple sclerosis, type 1 diabetes, and lupus. However, many approaches have been hindered by non-specific activity of immunosuppressive or immunoregulatory cues, following systemic administration of soluble factors via traditional injections routes (e.g., subcutaneous, intravenous). Biomaterials offer a unique opportunity to control the delivery of tolerogenic signals in vivo via properties such as controlled particle size, tunable release kinetics, and co-delivery of multiple classes of cargo. In this review, we highlight recent reports that exploit these properties of biomaterials to target APCs and promote tolerance via three strategies, i) passive or active targeting of particulate carriers to APCs, ii) biomaterial-mediated control over antigen localization and processing, and iii) targeted delivery of encapsulated or adsorbed immunomodulatory signals. These reports represent exciting advances toward the goal of more effective therapies for autoimmune diseases, without the broad suppressive effects associated with current clinically-approved therapies.

  12. Alternative approaches to pollution control and waste management: Regulatory and economic instruments

    International Nuclear Information System (INIS)

    Bernstein, J.D.

    1993-01-01

    The purpose of the paper is to present an overview of the most common strategies and policy instruments (that is, regulatory and economic) used in developed and developing countries to achieve pollution control and waste management objectives. Although this topic has been at the center of theoretical controversy both within and outside the World Bank, the paper is not intended to contribute to this debate. Rather, its purpose is to explore how regulatory and economic instruments are used to control air and water pollution, protect ground water, and manage solid and hazardous wastes. The paper is directed to policy makers at the national, state, and local levels of government, as well as to other parties responsible for pollution control and waste management programs

  13. Development and implementation of the regulatory control of sources in Latin American Model Project countries

    International Nuclear Information System (INIS)

    Ferruz Cruz, P.

    2001-01-01

    After a general assessment of the situation regarding radiation safety and the radiation protection infrastructure in Latin American countries, several of them were invited to participate in a Model Project oriented, in some cases, towards establishing a mechanism for national regulatory control of radiation sources, and in others, towards upgrading their national control programme. All these activities aimed at reaching an effective and sustainable radiation protection infrastructure based on international basic safety standards. The paper presents a general overview of the current situation with regard to radiation protection within the Model Project countries in Latin America after almost five years of activities. It includes: the implementation of regulatory issues; the control of occupational, medical and public exposures; emergency response and waste safety issues. The paper also presents some lessons learned during implementation concerning the numerous activities involved in this interregional project. (author)

  14. Implementation of fault-tolerant quantum logic gates via optimal control

    International Nuclear Information System (INIS)

    Nigmatullin, R; Schirmer, S G

    2009-01-01

    The implementation of fault-tolerant quantum gates on encoded logic qubits is considered. It is shown that transversal implementation of logic gates based on simple geometric control ideas is problematic for realistic physical systems suffering from imperfections such as qubit inhomogeneity or uncontrollable interactions between qubits. However, this problem can be overcome by formulating the task as an optimal control problem and designing efficient algorithms to solve it. In particular, we can find solutions that implement all of the elementary logic gates in a fixed amount of time with limited control resources for the five-qubit stabilizer code. Most importantly, logic gates that are extremely difficult to implement using conventional techniques even for ideal systems, such as the T-gate for the five-qubit stabilizer code, do not appear to pose a problem for optimal control.

  15. Fault-tolerant Control of Discrete-time LPV systems using Virtual Actuators and Sensors

    DEFF Research Database (Denmark)

    Tabatabaeipour, Mojtaba; Stoustrup, Jakob; Bak, Thomas

    2015-01-01

    This paper proposes a new fault-tolerant control (FTC) method for discrete-time linear parameter varying (LPV) systems using a reconfiguration block. The basic idea of the method is to achieve the FTC goal without re-designing the nominal controller by inserting a reconfiguration block between......, it transforms the output of the controller for the faulty system such that the stability and performance goals are preserved. Input-to-state stabilizing LPV gains of the virtual actuator and sensor are obtained by solving linear matrix inequalities (LMIs). We show that separate design of these gains guarantees....... Finally, the effectiveness of the method is demonstrated via a numerical example and stator current control of an induction motor....

  16. Robust Fault Tolerant Control for a Class of Time-Delay Systems with Multiple Disturbances

    Directory of Open Access Journals (Sweden)

    Songyin Cao

    2013-01-01

    Full Text Available A robust fault tolerant control (FTC approach is addressed for a class of nonlinear systems with time delay, actuator faults, and multiple disturbances. The first part of the multiple disturbances is supposed to be an uncertain modeled disturbance and the second one represents a norm-bounded variable. First, a composite observer is designed to estimate the uncertain modeled disturbance and actuator fault simultaneously. Then, an FTC strategy consisting of disturbance observer based control (DOBC, fault accommodation, and a mixed H2/H∞ controller is constructed to reconfigure the considered systems with disturbance rejection and attenuation performance. Finally, simulations for a flight control system are given to show the efficiency of the proposed approach.

  17. Studies for improvement of regulatory control on the radioactive effluent released from nuclear facilities

    International Nuclear Information System (INIS)

    Cheong, Jae Hak; Park, H. M.; Song, M. C.; Lee, K. H.; Jang, J. K.; Chun, J. K.; Jeong, K. H.

    2005-05-01

    This report contains the second-year results of the research project titled 'Studies for Improvement of Regulatory Control on the Radioactive Effluent Released from Nuclear Facilities' and mainly provides technical and strategic approaches to improve performance of regulatory control on the gaseous effluent released from domestic nuclear facilities. The main result contained here includes overview and technical bases of radioactive gaseous effluent control (Chapter 1), reconsideration of the sensitivity requirements for measurement of radioactivity in gaseous effluent sample (Chapter 2), uncertainty analysis of the calculated radioactivity in gaseous effluent (Chapter 3), and improvement of quantification method of noble gas releases (Chapter 4). In addition, analysis of the impact due to combined sampling of particulate from multiple release points (Chapter 5), comparison of domestic nuclear reactors gaseous effluent data to foreign PWRs (Chapter 6), standardized sampling technique for collection of gaseous tritium (Chapter 7), and application of Xe-133 equivalent concept to gaseous effluent control (Chapter 8) are also provided. As a whole, this report provides a generic approach to improve the performance of regulatory control on the gaseous effluent. Therefore, actual enforcement of the recommendations should be preceded by establishment of a series of action plans reflecting on the site- and facility-specific design and operational features

  18. Comparative genomics of metabolic capacities of regulons controlled by cis-regulatory RNA motifs in bacteria.

    Science.gov (United States)

    Sun, Eric I; Leyn, Semen A; Kazanov, Marat D; Saier, Milton H; Novichkov, Pavel S; Rodionov, Dmitry A

    2013-09-02

    In silico comparative genomics approaches have been efficiently used for functional prediction and reconstruction of metabolic and regulatory networks. Riboswitches are metabolite-sensing structures often found in bacterial mRNA leaders controlling gene expression on transcriptional or translational levels.An increasing number of riboswitches and other cis-regulatory RNAs have been recently classified into numerous RNA families in the Rfam database. High conservation of these RNA motifs provides a unique advantage for their genomic identification and comparative analysis. A comparative genomics approach implemented in the RegPredict tool was used for reconstruction and functional annotation of regulons controlled by RNAs from 43 Rfam families in diverse taxonomic groups of Bacteria. The inferred regulons include ~5200 cis-regulatory RNAs and more than 12000 target genes in 255 microbial genomes. All predicted RNA-regulated genes were classified into specific and overall functional categories. Analysis of taxonomic distribution of these categories allowed us to establish major functional preferences for each analyzed cis-regulatory RNA motif family. Overall, most RNA motif regulons showed predictable functional content in accordance with their experimentally established effector ligands. Our results suggest that some RNA motifs (including thiamin pyrophosphate and cobalamin riboswitches that control the cofactor metabolism) are widespread and likely originated from the last common ancestor of all bacteria. However, many more analyzed RNA motifs are restricted to a narrow taxonomic group of bacteria and likely represent more recent evolutionary innovations. The reconstructed regulatory networks for major known RNA motifs substantially expand the existing knowledge of transcriptional regulation in bacteria. The inferred regulons can be used for genetic experiments, functional annotations of genes, metabolic reconstruction and evolutionary analysis. The obtained genome

  19. Position, Attitude, and Fault-Tolerant Control of Tilting-Rotor Quadcopter

    Science.gov (United States)

    Kumar, Rumit

    The aim of this thesis is to present algorithms for autonomous control of tilt-rotor quadcopter UAV. In particular, this research work describes position, attitude and fault tolerant control in tilt-rotor quadcopter. Quadcopters are one of the most popular and reliable unmanned aerial systems because of the design simplicity, hovering capabilities and minimal operational cost. Numerous applications for quadcopters have been explored all over the world but very little work has been done to explore design enhancements and address the fault-tolerant capabilities of the quadcopters. The tilting rotor quadcopter is a structural advancement of traditional quadcopter and it provides additional actuated controls as the propeller motors are actuated for tilt which can be utilized to improve efficiency of the aerial vehicle during flight. The tilting rotor quadcopter design is accomplished by using an additional servo motor for each rotor that enables the rotor to tilt about the axis of the quadcopter arm. Tilting rotor quadcopter is a more agile version of conventional quadcopter and it is a fully actuated system. The tilt-rotor quadcopter is capable of following complex trajectories with ease. The control strategy in this work is to use the propeller tilts for position and orientation control during autonomous flight of the quadcopter. In conventional quadcopters, two propellers rotate in clockwise direction and other two propellers rotate in counter clockwise direction to cancel out the effective yawing moment of the system. The variation in rotational speeds of these four propellers is utilized for maneuvering. On the other hand, this work incorporates use of varying propeller rotational speeds along with tilting of the propellers for maneuvering during flight. The rotational motion of propellers work in sync with propeller tilts to control the position and orientation of the UAV during the flight. A PD flight controller is developed to achieve various modes of the

  20. Development of an interface for an ultrareliable fault-tolerant control system and an electronic servo-control unit

    Science.gov (United States)

    Shaver, Charles; Williamson, Michael

    1986-01-01

    The NASA Ames Research Center sponsors a research program for the investigation of Intelligent Flight Control Actuation systems. The use of artificial intelligence techniques in conjunction with algorithmic techniques for autonomous, decentralized fault management of flight-control actuation systems is explored under this program. The design, development, and operation of the interface for laboratory investigation of this program is documented. The interface, architecturally based on the Intel 8751 microcontroller, is an interrupt-driven system designed to receive a digital message from an ultrareliable fault-tolerant control system (UFTCS). The interface links the UFTCS to an electronic servo-control unit, which controls a set of hydraulic actuators. It was necessary to build a UFTCS emulator (also based on the Intel 8751) to provide signal sources for testing the equipment.

  1. Exemption from Regulatory Control of Goods Containing Small Amounts of Radioactive Material

    International Nuclear Information System (INIS)

    2012-01-01

    Small amounts of radioactive material may be added to various goods for functional reasons. Several such items are currently available for either professional or personal use. These include ionization chamber smoke detectors, thoriated-tungsten welding rods, luminous dials, electrical devices and electric discharge lamps. Some of these goods may be intended for particular types of market such as cinemas or other places to which the public may have access, but they are unlikely to be provided directly to members of the public. Other goods may be intended for wide scale use and therefore readily available on the market as consumer products through commercial outlets where personal and household products are normally purchased. Members of the public may be exposed to ionizing radiation as a consequence of activities such as transport, storage, use and disposal of such goods. The IAEA safety standards provide the basic requirements for regulatory control of such goods. The most relevant documents are the Governmental, Legal and Regulatory Framework for Safety and the International Basic Safety Standards (hereafter referred to as the BSS). These requirements include notification of a practice to the regulatory body and authorization of the practice by the regulatory body. Provision is made for the exemption of practices from these and other regulatory requirements based on general criteria given in the BSS or any exemption levels specified by the regulatory body on the basis of these criteria. The BSS, which are jointly sponsored by the IAEA and several other international organizations, apply to all facilities and all activities for peaceful purposes that give rise to exposure to radiation. In the interest of harmonization of approaches among Member States, some guidance on the application of the criteria for exemption has been provided in a number of Safety Guides, e.g. Regulatory Control of Radiation Sources, IAEA Safety Standards Series No. GS-G-1.5 (2004) and the

  2. Fault-tolerant design of adaptive digital control systems for power plant components

    International Nuclear Information System (INIS)

    Parlos, A.G.; Menon, S.K.

    1992-01-01

    An adaptive controller has been designed for the water level of a Westinghouse type U-tube steam generator, and its operation has been demonstrated in the entire power range via computer simulations. The proposed design exhibits improved performance, at low operating powers, a,s compared to existing controller types. The continuous-time controller design is performed systematically via the Linear Quadratic Gaussian/Loop Transfer Recovery method, followed by gain adaptation allowing controller operation in the entire power range. Digital implementation of the controller is accomplished by a digital redesign which results in matching the digital and continuous-time system and controller states. It is only at this stage of the control system design process that issues such as microprocessor induced quantization effects are taken into account. The use of computer-aided-design software greatly expedites the design cycle, allowing the designer to maximize the controller stability robustness to uncertainties via numerous iterations. This inherent controller robustness can be exploited to tolerate incipient plant faults, such as deteriorating U-tube heat transfer properties, without significant loss of controller performance

  3. Intelligent on-line fault tolerant control for unanticipated catastrophic failures.

    Science.gov (United States)

    Yen, Gary G; Ho, Liang-Wei

    2004-10-01

    As dynamic systems become increasingly complex, experience rapidly changing environments, and encounter a greater variety of unexpected component failures, solving the control problems of such systems is a grand challenge for control engineers. Traditional control design techniques are not adequate to cope with these systems, which may suffer from unanticipated dynamic failures. In this research work, we investigate the on-line fault tolerant control problem and propose an intelligent on-line control strategy to handle the desired trajectories tracking problem for systems suffering from various unanticipated catastrophic faults. Through theoretical analysis, the sufficient condition of system stability has been derived and two different on-line control laws have been developed. The approach of the proposed intelligent control strategy is to continuously monitor the system performance and identify what the system's current state is by using a fault detection method based upon our best knowledge of the nominal system and nominal controller. Once a fault is detected, the proposed intelligent controller will adjust its control signal to compensate for the unknown system failure dynamics by using an artificial neural network as an on-line estimator to approximate the unexpected and unknown failure dynamics. The first control law is derived directly from the Lyapunov stability theory, while the second control law is derived based upon the discrete-time sliding mode control technique. Both control laws have been implemented in a variety of failure scenarios to validate the proposed intelligent control scheme. The simulation results, including a three-tank benchmark problem, comply with theoretical analysis and demonstrate a significant improvement in trajectory following performance based upon the proposed intelligent control strategy.

  4. Fault Detection and Isolation and Fault Tolerant Control of Wind Turbines Using Set-Valued Observers

    DEFF Research Database (Denmark)

    Casau, Pedro; Rosa, Paulo Andre Nobre; Tabatabaeipour, Seyed Mojtaba

    2012-01-01

    Research on wind turbine Operations & Maintenance (O&M) procedures is critical to the expansion of Wind Energy Conversion systems (WEC). In order to reduce O&M costs and increase the lifespan of the turbine, we study the application of Set-Valued Observers (SVO) to the problem of Fault Detection...... and Isolation (FDI) and Fault Tolerant Control (FTC) of wind turbines, by taking advantage of the recent advances in SVO theory for model invalidation. A simple wind turbine model is presented along with possible faulty scenarios. The FDI algorithm is built on top of the described model, taking into account...

  5. Fault-tolerant controlled quantum secure direct communication over a collective quantum noise channel

    International Nuclear Information System (INIS)

    Yang, Chun-Wei; Hwang, Tzonelih; Tsai, Chia-Wei

    2014-01-01

    This work proposes controlled quantum secure direct communication (CQSDC) over an ideal channel. Based on the proposed CQSDC, two fault-tolerant CQSDC protocols that are robust under two kinds of collective noises, collective-dephasing noise and collective-rotation noise, respectively, are constructed. Due to the use of quantum entanglement of the Bell state (or logical Bell state) as well as dense coding, the proposed protocols provide easier implementation as well as better qubit efficiency than other CQSDC protocols. Furthermore, the proposed protocols are also free from correlation-elicitation attack and other well-known attacks. (paper)

  6. Consigned regulatory control and effect of the owner's welding quality under the EPC mode in Fangjiashan nuclear power project

    International Nuclear Information System (INIS)

    Wang Qun; Gu Tao; Wei Lianfeng; Li Hongjun

    2012-01-01

    Under EPC management mode, how to optimize resources allocation and realize effective management and control over key control points is a big difficulty facing the owner. From the owner's point of view, and through summary of practices, the paper introduces and analyses the mode and effect of consigned regulatory control over the weld quality of Fangjiashan nuclear power project. And some recognitions and point of views on popularization of specialized and consigned regulatory control are put forward. (authors)

  7. The effects of age, glucose ingestion and gluco-regulatory control on episodic memory.

    Science.gov (United States)

    Riby, Leigh Martin; Meikle, Andrew; Glover, Cheryl

    2004-09-01

    Previous research has been inconclusive regarding the impact of glucose ingestion and gluco-regulatory control on cognitive performance in healthy older adults. The aim of this research was to determine whether glucose specifically enhanced episodic memory in an older population. In addition, the link between individual differences in glucose regulation and the magnitude of the enhancement effect was examined. A within subjects, counterbalanced, crossover design was used with 20 participants (60-80 year olds), each serving as his/her control. Episodic memory was tested by presenting unrelated paired associates followed by immediate and delayed cued recall, and delayed recognition, under single and dual task conditions. In addition, a battery of cognitive tests was administered, including tests of semantic memory, working memory and speed of processing. Glucose ingestion was found to largely facilitate performance of episodic memory. Furthermore, subsidiary analyses found that gluco-regulatory efficiency predicted episodic memory performance in both control and glucose conditions. A boost in performance after glucose ingestion was particularly seen in the episodic memory domain. Notably, strong evidence was provided for the utility of gluco-regulatory control measures as indicators of cognitive decline in the elderly.

  8. The Neural Correlates of Self-Regulatory Fatigability During Inhibitory Control of Eye Blinking.

    Science.gov (United States)

    Abi-Jaoude, Elia; Segura, Barbara; Cho, Sang Soo; Crawley, Adrian; Sandor, Paul

    2018-05-30

    The capacity to regulate urges is an important human characteristic associated with a range of social and health outcomes. Self-regulatory capacity has been postulated to have a limited reserve, which when depleted leads to failure. The authors aimed to investigate the neural correlates of self-regulatory fatigability. Functional MRI was used to detect brain activations in 19 right-handed healthy subjects during inhibition of eye blinking, in a block design. The increase in number of blinks during blink inhibition from the first to the last block was used as covariate of interest. There was an increase in the number of eye blinks escaping inhibitory control across blink inhibition blocks, whereas there was no change in the number of eye blinks occurring during rest blocks. Inhibition of blinking activated a wide network bilaterally, including the inferior frontal gyrus, dorsolateral prefrontal cortex, dorsal anterior cingulate cortex, supplementary motor area, and caudate. Deteriorating performance was associated with activity in orbitofrontal cortex, ventromedial prefrontal cortex, rostroventral anterior cingulate cortex, precuneus, somatosensory, and parietal areas. As anticipated, effortful eye-blink control resulted in activation of prefrontal control areas and regions involved in urge and interoceptive processing. Worsening performance was associated with activations in brain areas involved in urge, as well as regions involved in motivational evaluation. These findings suggest that self-regulatory fatigability is associated with relatively less recruitment of prefrontal cortical regions involved in executive control.

  9. National Program Initiative to Prevent Illicit Trafficking for Radioactive Materials Out of Regulatory Control at the Border

    International Nuclear Information System (INIS)

    Suharyanta, S.

    2016-01-01

    The existing function of regulatory authority in a country which use a lot of radioactive sources is important key. The regulatory body has to in a position independence from other operators and nuclear research centre activities, so that their justification on Regulatory objective of safety and security can be achieved. The essential function of regulatory authority has to be represented such as development regulations, perform review and assessment, inspection and enforcement, and emergency preparedness and response functions. Under regulatory object coverage is divided into two clusters i.e. licensed nuclear installation and radiation facilities clusters,. There is other regulatory object is radioactive material out of regulatory control. This kind object is new option in the county and there for need priority policy judgement. This paper will discuss the Regulatory infrastructure and functions and it focused on the experience about National Programme Initiative to Prevent Illicit Trafficking for Radioactive Materials out of Regulatory Control at the Border. Regulatory Infrastructure and Functions. In Indonesia the independent regulatory authority ''called BAPETEN'' has been established since early 2000 based on the Act No. 10 year 1997, independent from operator organization and other nuclear research centre. Organization structure of BAPETEN has defined main divisions dealing with developing regulations, perform review and assessments, inspection and enforcement, and emergency preparedness and response, and also covered assessment function as a backup technical support division as a think-tank functions. Regulatory objects are nuclear installations such as three research reactors, Fuel fabrication facility, Isotope production facility, and waste storage facility for spent fuel and dis-used radioactive sources is running well. Recently, Regulatory of radioactive sources out of regulatory control is a new challenges, they need strengthened

  10. Fault diagnosis and fault-tolerant control and guidance for aerospace vehicles from theory to application

    CERN Document Server

    Zolghadri, Ali; Cieslak, Jerome; Efimov, Denis; Goupil, Philippe

    2014-01-01

    Fault Diagnosis and Fault-Tolerant Control and Guidance for Aerospace demonstrates the attractive potential of recent developments in control for resolving such issues as improved flight performance, self-protection and extended life of structures. Importantly, the text deals with a number of practically significant considerations: tuning, complexity of design, real-time capability, evaluation of worst-case performance, robustness in harsh environments, and extensibility when development or adaptation is required. Coverage of such issues helps to draw the advanced concepts arising from academic research back towards the technological concerns of industry. Initial coverage of basic definitions and ideas and a literature review gives way to a treatment of important electrical flight control system failures: the oscillatory failure case, runaway, and jamming. Advanced fault detection and diagnosis for linear and nonlinear systems are described. Lastly recovery strategies appropriate to remaining acuator/sensor/c...

  11. Nuclear Security Recommendations on Nuclear and other Radioactive Material out of Regulatory Control: Recommendations (Spanish Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications.

  12. Nuclear Security Recommendations on Nuclear and Other Radioactive Material out of Regulatory Control: Recommendations (Arabic Edition)

    International Nuclear Information System (INIS)

    2012-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the ? field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications.

  13. Nuclear Security Recommendations on Nuclear and Other Radioactive Material out of Regulatory Control: Recommendations

    International Nuclear Information System (INIS)

    2011-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications

  14. Nuclear Security Recommendations on Nuclear and Other Radioactive Material out of Regulatory Control: Recommendations (Russian Edition)

    International Nuclear Information System (INIS)

    2011-01-01

    This publication presents recommendations for the nuclear security of nuclear and other radioactive material that is out of regulatory control. It is based on national experiences and practices and guidance publications in the field of security as well as the nuclear security related international instruments. The recommendations include guidance for States with regard to the nuclear security of nuclear and other radioactive material that has been reported as being out of regulatory control as well as for material that is lost, missing or stolen but has not been reported as such, or has been otherwise discovered. In addition, these recommendations adhere to the detection and assessment of alarms and alerts and to a graded response to criminal or unauthorized acts with nuclear security implications.

  15. Principles for the exemption of radiation sources and practices from regulatory control

    International Nuclear Information System (INIS)

    1988-01-01

    Radiation sources, including equipment and installations, which emit ionizing radiations, are potentially harmful to health and their use should therefore be regulated. Some types of radiation source, however, do not need to be subject to regulatory control, because they present such a low hazard that it would be a needless waste of time and effort to exercise control by a regulatory process and they can therefore be exempted from it. An Advisory Group Meeting was convened in Vienna in March 1988 sponsored jointly by the IAEA and NEA. This Safety Guide is the result of that meeting and represents a first international consensus on the subject of exemption principles. This document is issued as an IAEA Safety Guide since it recommends a procedure which might be followed in implementing the Basic Safety Standards (BSS) for Radiation Protection. Its purpose is to recommend a policy on exemptions from the BSS system of notification, registration and licensing. 15 refs

  16. Fault Diagnosis and Fault-Tolerant Control of Wind Turbines via a Discrete Time Controller with a Disturbance Compensator

    Directory of Open Access Journals (Sweden)

    Yolanda Vidal

    2015-05-01

    Full Text Available This paper develops a fault diagnosis (FD and fault-tolerant control (FTC of pitch actuators in wind turbines. This is accomplished by combining a disturbance compensator with a controller, both of which are formulated in the discrete time domain. The disturbance compensator has a dual purpose: to estimate the actuator fault (which is used by the FD algorithm and to design the discrete time controller to obtain an FTC. That is, the pitch actuator faults are estimated, and then, the pitch control laws are appropriately modified to achieve an FTC with a comparable behavior to the fault-free case. The performance of the FD and FTC schemes is tested in simulations with the aero-elastic code FAST.

  17. A balance of activity in brain control and reward systems predicts self-regulatory outcomes.

    Science.gov (United States)

    Lopez, Richard B; Chen, Pin-Hao A; Huckins, Jeremy F; Hofmann, Wilhelm; Kelley, William M; Heatherton, Todd F

    2017-05-01

    Previous neuroimaging work has shown that increased reward-related activity following exposure to food cues is predictive of self-control failure. The balance model suggests that self-regulation failures result from an imbalance in reward and executive control mechanisms. However, an open question is whether the relative balance of activity in brain systems associated with executive control (vs reward) supports self-regulatory outcomes when people encounter tempting cues in daily life. Sixty-nine chronic dieters, a population known for frequent lapses in self-control, completed a food cue-reactivity task during an fMRI scanning session, followed by a weeklong sampling of daily eating behaviors via ecological momentary assessment. We related participants' food cue activity in brain systems associated with executive control and reward to real-world eating patterns. Specifically, a balance score representing the amount of activity in brain regions associated with self-regulatory control, relative to automatic reward-related activity, predicted dieters' control over their eating behavior during the following week. This balance measure may reflect individual self-control capacity and be useful for examining self-regulation success in other domains and populations. © The Author (2017). Published by Oxford University Press.

  18. A Controlled Trial of CPAP Therapy on Metabolic Control in Individuals with Impaired Glucose Tolerance and Sleep Apnea

    Science.gov (United States)

    Weinstock, Tanya G.; Wang, Xuelei; Rueschman, Michael; Ismail-Beigi, Faramarz; Aylor, Joan; Babineau, Denise C.; Mehra, Reena; Redline, Susan

    2012-01-01

    Study Objectives: To address whether treatment of sleep apnea improves glucose tolerance. Design: Randomized, double-blind crossover study. Setting: Sleep clinic referrals. Patients: 50 subjects with moderate to severe sleep apnea (AHI > 15) and impaired glucose tolerance. Interventions: Subjects were randomized to 8 weeks of CPAP or sham CPAP, followed by the alternate therapy after a one-month washout. After each treatment, subjects underwent 2-hour OGTT, polysomnography, actigraphy, and measurements of indices of glucose control. Measurements and Results: The primary outcome was normalization of the mean 2-h OGTT; a secondary outcome was improvement in the Insulin Sensitivity Index (ISI (0,120). Subjects were 42% men, mean age of 54 (10), BMI of 39 (8), and AHI of 44 (27). Baseline fasting glucose was 104 (12), and mean 2-h OGTT was 110 (57) mg/dL. Seven subjects normalized their mean 2-h OGTT after CPAP but not after sham CPAP, while 5 subjects normalized after sham CPAP but not after CPAP. Overall, there was no improvement in ISI (0,120) between CPAP and sham CPAP (3.6%; 95% CI: [-2.2%, 9.7%]; P = 0.22). However, in those subjects with baseline AHI ≥ 30 (n = 25), there was a 13.3% (95% CI: [5.2%, 22.1%]; P CPAP compared to sham CPAP. Conclusions: This study did not show that IGT normalizes after CPAP in subjects with moderate sleep apnea and obesity. However, insulin sensitivity improved in those with AHI ≥ 30, suggesting beneficial metabolic effects of CPAP in severe sleep apnea. Clinical Trials Information: ClinicalTrials.gov Identifier: NCT01385995. Citation: Weinstock TG; Wang X; Rueschman M; Ismail-Beigi F; Aylor J; Babineau DC; Mehra R; Redline S. A controlled trial of CPAP therapy on metabolic control in individuals with impaired glucose tolerance and sleep apnea. SLEEP 2012;35(5):617-625. PMID:22547887

  19. A Framework for Probabilistic Evaluation of Interval Management Tolerance in the Terminal Radar Control Area

    Science.gov (United States)

    Hercencia-Zapana, Heber; Herencia-Zapana, Heber; Hagen, George E.; Neogi, Natasha

    2012-01-01

    Projections of future traffic in the national airspace show that most of the hub airports and their attendant airspace will need to undergo significant redevelopment and redesign in order to accommodate any significant increase in traffic volume. Even though closely spaced parallel approaches increase throughput into a given airport, controller workload in oversubscribed metroplexes is further taxed by these approaches that require stringent monitoring in a saturated environment. The interval management (IM) concept in the TRACON area is designed to shift some of the operational burden from the control tower to the flight deck, placing the flight crew in charge of implementing the required speed changes to maintain a relative spacing interval. The interval management tolerance is a measure of the allowable deviation from the desired spacing interval for the IM aircraft (and its target aircraft). For this complex task, Formal Methods can help to ensure better design and system implementation. In this paper, we propose a probabilistic framework to quantify the uncertainty and performance associated with the major components of the IM tolerance. The analytical basis for this framework may be used to formalize both correctness and probabilistic system safety claims in a modular fashion at the algorithmic level in a way compatible with several Formal Methods tools.

  20. A Multi-Environment Thermal Control System With Freeze-Tolerant Radiator

    Science.gov (United States)

    Chen, Weibo; Fogg, David; Mancini, Nick; Steele, John; Quinn, Gregory; Bue, Grant; Littibridge, Sean

    2013-01-01

    Future space exploration missions require advanced thermal control systems (TCS) to dissipate heat from spacecraft, rovers, or habitats operating in environments that can vary from extremely hot to extremely cold. A lightweight, reliable TCS is being developed to effectively control cabin and equipment temperatures under widely varying heat loads and ambient temperatures. The system uses freeze-tolerant radiators, which eliminate the need for a secondary circulation loop or heat pipe systems. Each radiator has a self-regulating variable thermal conductance to its ambient environment. The TCS uses a nontoxic, water-based working fluid that is compatible with existing lightweight aluminum heat exchangers. The TCS is lightweight, compact, and requires very little pumping power. The critical characteristics of the core enabling technologies were demonstrated. Functional testing with condenser tubes demonstrated the key operating characteristics required for a reliable, freeze-tolerant TCS, namely (1) self-regulating thermal conductance with short transient responses to varying thermal loads, (2) repeatable performance through freeze-thaw cycles, and (3) fast start-up from a fully frozen state. Preliminary coolant tests demonstrated that the corrosion inhibitor in the water-based coolant can reduce the corrosion rate on aluminum by an order of magnitude. Performance comparison with state-of-the-art designs shows significant mass and power saving benefits of this technology.

  1. Tolerating dissimilar other when primed with death: neural evidence of self-control engaged by interdependent people in Japan.

    Science.gov (United States)

    Yanagisawa, Kuniaki; Kashima, Emiko S; Moriya, Hiroki; Masui, Keita; Furutani, Kaichiro; Yoshida, Hiroshi; Ura, Mitsuhiro; Nomura, Michio

    2017-06-01

    Mortality salience (MS) has been shown to lead to derogation of others with dissimilar worldviews, yet recent research has shown that Asian-Americans who presumably adopt an interdependent self-construal (SC) tend to reveal greater tolerance after MS induction. In the present study, we demonstrated that Japanese individuals who are high on interdependent SC indeed show greater tolerance toward worldview-threatening other in the MS (vs control) condition, thus replicating the prior research. Extending this research, we also found that interdependent people's tolerance toward worldview-threatening other was mediated by increased activity in the right ventrolateral prefrontal cortex in the MS condition. These data suggested that when exposed to death-related stimuli, highly interdependent individuals may spontaneously activate their neural self-control system which may serve to increase tolerance toward others. © The Author (2017). Published by Oxford University Press.

  2. Adaptive Fault-Tolerant Tracking Control of Nonaffine Nonlinear Systems with Actuator Failure

    Directory of Open Access Journals (Sweden)

    Hongcheng Zhou

    2014-01-01

    Full Text Available This paper proposes an adaptive fault-tolerant control scheme for nonaffine nonlinear systems. A model approximation method which is a solution that bridges the gap between affine and nonaffine control systems is developed firstly. A joint estimation approach is based on unscented Kalman filter, in which both failure parameters and states are simultaneously estimated by means of the argument state vector composed of the unknown faults and states. Then, stability analysis is given for the closed-loop system. Finally, the proposed approach is verified using a three-degree-of-freedom simulation of a typical fighter aircraft and the significantly improved system response demonstrates the practical potential of the theoretic results obtained.

  3. Sensor-driven, fault-tolerant control of a maintenance robot

    International Nuclear Information System (INIS)

    Moy, M.M.; Davidson, W.M.

    1987-01-01

    A robot system has been designed to do routine maintenance tasks on the Sandia Pulsed Reactor (SPR). The use of this Remote Maintenance Robot (RMR) is expected to significantly reduce the occupational radiation exposure of the reactor operators. Reactor safety was a key issue in the design of the robot maintenance system. Using sensors to detect error conditions and intelligent control to recover from the errors, the RMR is capable of responding to error conditions without creating a hazard. This paper describes the design and implementation of a sensor-driven, fault-tolerant control for the RMR. Recovery from errors is not automatic; it does rely on operator assistance. However, a key feature of the error recovery procedure is that the operator is allowed to reenter the programmed operation after the error has been corrected. The recovery procedure guarantees that the moving components of the system will not collide with the reactor during recovery

  4. A regulatory network-based approach dissects late maturation processes related to the acquisition of desiccation tolerance and longevity of Medicago truncatula seeds.

    Science.gov (United States)

    Verdier, Jerome; Lalanne, David; Pelletier, Sandra; Torres-Jerez, Ivone; Righetti, Karima; Bandyopadhyay, Kaustav; Leprince, Olivier; Chatelain, Emilie; Vu, Benoit Ly; Gouzy, Jerome; Gamas, Pascal; Udvardi, Michael K; Buitink, Julia

    2013-10-01

    In seeds, desiccation tolerance (DT) and the ability to survive the dry state for prolonged periods of time (longevity) are two essential traits for seed quality that are consecutively acquired during maturation. Using transcriptomic and metabolomic profiling together with a conditional-dependent network of global transcription interactions, we dissected the maturation events from the end of seed filling to final maturation drying during the last 3 weeks of seed development in Medicago truncatula. The network revealed distinct coexpression modules related to the acquisition of DT, longevity, and pod abscission. The acquisition of DT and dormancy module was associated with abiotic stress response genes, including late embryogenesis abundant (LEA) genes. The longevity module was enriched in genes involved in RNA processing and translation. Concomitantly, LEA polypeptides accumulated, displaying an 18-d delayed accumulation compared with transcripts. During maturation, gulose and stachyose levels increased and correlated with longevity. A seed-specific network identified known and putative transcriptional regulators of DT, including ABSCISIC ACID-INSENSITIVE3 (MtABI3), MtABI4, MtABI5, and APETALA2/ ETHYLENE RESPONSE ELEMENT BINDING PROTEIN (AtAP2/EREBP) transcription factor as major hubs. These transcriptional activators were highly connected to LEA genes. Longevity genes were highly connected to two MtAP2/EREBP and two basic leucine zipper transcription factors. A heat shock factor was found at the transition of DT and longevity modules, connecting to both gene sets. Gain- and loss-of-function approaches of MtABI3 confirmed 80% of its predicted targets, thereby experimentally validating the network. This study captures the coordinated regulation of seed maturation and identifies distinct regulatory networks underlying the preparation for the dry and quiescent states.

  5. Evaluation of Freezing Tolerance of Three Ajowan (Trachyspermum ammi (Linn. Sprague Ecotypes in Controlled Conditions

    Directory of Open Access Journals (Sweden)

    Z Boroumand Rezazadeh

    2013-08-01

    Full Text Available Ajowan is one of the endemic plants in Khorasan province, and there is a little information on its tolerance to cold stress. In order to study freezing tolerance of ajowan, an experiment was conducted in faculty of agriculture, Ferdowsi University of Mashhad, based on factorial-completely randomized design with three replications and three ecotypes of ajowan (Neishabour, Birjand and Torbat-e-Heidarieh were imposed on eight freezing temperatures (0 (control, -1.5, -3, -4.5, -6,-7.5, -9 and -10.5 °C. Plants were grown in natural environment till 4-5 leaf stage, then for freezing treatments transferred to thermo-gradient freezer. The cell membrane stability was evaluated by electrolyte leakage index (EL and temperature for killing 50% of samples according to the electrolyte leakage (LT50el was determined. Furthermore, survival percentage, leaf number and dry weight, temperature for killing 50% of samples according to survival (LT50su and reduced dry matter temperature 50 (RDMT50 were determined after three weeks recovery in the glasshouse. Response of ajowan ecotypes for electrolyte leakage was different and birjand ecotype had the lowest %EL, whereas the slope of %EL in mentioned ecotype was lower than two other ecotypes. However there were no significant differences among ajowan ecotypes on LT50su. Decreasing temperature to -7.5 °C reduced survival percentage of Neishabour and Torbat-e-Heidarieh ecotypes to lower than 20 percent, whiles in this temperature Birjand’s survival percentage was about 60 percent. It seems that Birjand ecotype with the lowest electrolyte leakage, the highest survival and dry matter and the lowest LT50su was more tolerant than two other ecotypes.

  6. Balancing technical and regulatory concerns related to testing and control of performance assessment software

    International Nuclear Information System (INIS)

    Seitz, R.R.; Matthews, S.D.; Kostelnik, K.M.

    1990-01-01

    What activities are required to assure that a performance assessment (PA) computer code operates as it is intended? Answers to this question will vary depending on the individual's area of expertise. Different perspectives on testing and control of PA software are discussed based on interpretations of the testing and control process associated with the different involved parties. This discussion leads into the presentation of a general approach to software testing and control that address regulatory requirements. Finally, the need for balance between regulatory and scientific concerns is illustrated through lessons learned in previous implementations of software testing and control programs. Configuration control and software testing are required to provide assurance that a computer code performs as intended. Configuration control provides traceability and reproducibility of results produced with PA software and provides a system to assure that users have access to the current version of the software. Software testing is conducted to assure that the computer code has been written properly, solution techniques have been properly implemented, and the software is capable of representing the behavior of the specific system to be modeled. Comprehensive software testing includes: software analysis, verification testing, benchmark testing, and site-specific calibration/validation testing

  7. Regulatory Initiatives for Control and Release of Technologically Enhanced Naturally-Occurring Radioactive Materials

    Energy Technology Data Exchange (ETDEWEB)

    Egidi, P.V.

    1999-03-02

    Current drafts of proposed standards and suggested State regulations for control and release of technologically-enhanced naturally-occurring radioactive material (TENORM), and standards for release of volumetrically-contaminated material in the US are reviewed. These are compared to the recommendations of the International Atomic Energy Association (IAEA) Safety Series and the European Commission (EC) proposals. Past regulatory efforts with respect to TENORM in the US dealt primarily with oil-field related wastes. Currently, nine states (AK, GA, LA, MS, NM, OH, OR SC, TX) have specific regulations pertaining to TENORM, mostly based on uranium mill tailings cleanup criteria. The new US proposals are dose- or risk-based, as are the IAEA and EC recommendations, and are grounded in the linear no threshold hypothesis (LNT). TENORM wastes involve extremely large volumes, particularly scrap metal and mine wastes. Costs to control and dispose of these wastes can be considerable. The current debate over the validity of LNT at low doses and low dose rates is particularly germane to this discussion. Most standards setting organizations and regulatory agencies base their recommendations on the LNT. The US Environmental Protection Agency has released a draft Federal Guidance Report that recommends calculating health risks from low-level exposure to radionuclides based on the LNT. However, some scientific and professional organizations are openly questioning the validity of LNT and its basis for regulations, practices, and costs to society in general. It is not clear at this time how a non-linear regulatory scheme would be implemented.

  8. Regulatory Initiatives for Control and Release of Technologically Enhanced Naturally-Occurring Radioactive Material

    International Nuclear Information System (INIS)

    Egidi, P.V.

    1999-01-01

    Current drafts of proposed standards and suggested State regulations for control and release of technologically-enhanced naturally-occurring radioactive material (TENORM), and standards for release of volumetrically-contaminated material in the US are reviewed. These are compared to the recommendations of the International Atomic Energy Association (IAEA) Safety Series and the European Commission (EC) proposals. Past regulatory efforts with respect to TENORM in the US dealt primarily with oil-field related wastes. Currently, nine states (AK, GA, LA, MS, NM, OH, OR SC, TX) have specific regulations pertaining to TENORM, mostly based on uranium mill tailings cleanup criteria. The new US proposals are dose- or risk-based, as are the IAEA and EC recommendations, and are grounded in the linear no threshold hypothesis (LNT). TENORM wastes involve extremely large volumes, particularly scrap metal and mine wastes. Costs to control and dispose of these wastes can be considerable. The current debate over the validity of LNT at low doses and low dose rates is particularly germane to this discussion. Most standards setting organizations and regulatory agencies base their recommendations on the LNT. The US Environmental Protection Agency has released a draft Federal Guidance Report that recommends calculating health risks from low-level exposure to radionuclides based on the LNT. However, some scientific and professional organizations are openly questioning the validity of LNT and its basis for regulations, practices, and costs to society in general. It is not clear at this time how a non-linear regulatory scheme would be implemented

  9. The Importance of the Nurse Cells and Regulatory Cells in the Control of T Lymphocyte Responses

    Directory of Open Access Journals (Sweden)

    María Guadalupe Reyes García

    2013-01-01

    Full Text Available T lymphocytes from the immune system are bone marrow-derived cells whose development and activities are carefully supervised by two sets of accessory cells. In the thymus, the immature young T lymphocytes are engulfed by epithelial “nurse cells” and retained in vacuoles, where most of them (95% are negatively selected and removed when they have an incomplete development or express high affinity autoreactive receptors. The mature T lymphocytes that survive to this selection process leave the thymus and are controlled in the periphery by another subpopulation of accessory cells called “regulatory cells,” which reduce any excessive immune response and the risk of collateral injuries to healthy tissues. By different times and procedures, nurse cells and regulatory cells control both the development and the functions of T lymphocyte subpopulations. Disorders in the T lymphocytes development and migration have been observed in some parasitic diseases, which disrupt the thymic microenvironment of nurse cells. In other cases, parasites stimulate rather than depress the functions of regulatory T cells decreasing T-mediated host damages. This paper is a short review regarding some features of these accessory cells and their main interactions with T immature and mature lymphocytes. The modulatory role that neurotransmitters and hormones play in these interactions is also revised.

  10. A discussion on the resilience of command and control regulation within regulatory behavior theories

    Directory of Open Access Journals (Sweden)

    K.P.V. O’Sullivan

    2012-03-01

    Full Text Available This paper provides the first insights into the factors that may drive the resilience of command and control regulation in modern policy making. We show how the forces of uncertainty and internal dynamics among customers, producers and regulators are the most dominate factors preventing the adoption of non-CAC regulations. Using case study evidence of internet regulation, we then integrate our analysis into the most prominent regulatory choice behavior theories and illustrate that regardless of the theory, these factors can help explain the dominance of command and control as a choice of regulation.

  11. Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

    Science.gov (United States)

    Williams, Wyatt I.; Friedman, Jonathan M.; Gaskin, John F.; Norton, Andrew P.

    2014-01-01

    Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgression between two parent species of the invasive shrub tamarisk (Tamarix spp.) in the western United States, and how differences in plant traits affect interactions with a biological control agent. Introgression varied strongly with latitude of origin and was highly correlated with plant performance. Increased levels of T. ramosissima introgression resulted in both higher investment in roots and tolerance to defoliation and less resistance to insect attack. Because tamarisk hybridization occurs predictably on the western U.S. landscape, managers may be able to exploit this information to maximize control efforts. Genetic differentiation in plant traits in this system underpins the importance of plant hybridization and may explain why some biological control releases are more successful than others.

  12. Regulatory philosophy and requirements for radiation control in Canadian uranium mine-mill facilities

    International Nuclear Information System (INIS)

    Dory, A.B.

    1981-10-01

    The approach the Canadian Atomic Energy Control Board takes in licensing uranium mine/mill facilities is based on a minimum of rigidly set regulatory requirements. The regulations state only the basic objectives: the obligation to acquire a licence, some administrative and reporting requirements, and exposure limits. The regulations are supported by a set of regulatory guides. The operator always has the option of following different procedures if he can demonstrate that they will produce the same or better results. Good relationships exist between the AECB and mine management as well as trade unions. Under this approach, however, it is difficult to take action against uncooperative parties. The Board has decided that a somewhat more formalized system is necessary. New regulations are being drafted, giving more detailed licensing and administrative requirements and covering the areas of ventilation and worker and supervisor education more thoroughly

  13. Fault Tolerance Automotive Air-Ratio Control Using Extreme Learning Machine Model Predictive Controller

    OpenAIRE

    Pak Kin Wong; Hang Cheong Wong; Chi Man Vong; Tong Meng Iong; Ka In Wong; Xianghui Gao

    2015-01-01

    Effective air-ratio control is desirable to maintain the best engine performance. However, traditional air-ratio control assumes the lambda sensor located at the tail pipe works properly and relies strongly on the air-ratio feedback signal measured by the lambda sensor. When the sensor is warming up during cold start or under failure, the traditional air-ratio control no longer works. To address this issue, this paper utilizes an advanced modelling technique, kernel extreme learning machine (...

  14. Evaluation of Freeze Tolerance in Lancelot Plantain (Plantago lanceolata L. Ecotypes under Controlled Conditions

    Directory of Open Access Journals (Sweden)

    M. Janalizadeh

    2016-02-01

    Full Text Available Introduction Lancelot Plantain (Ribwort, narrow-leaf or English plantain is a deep-rooted, short-lived perennial herb from Plantaginaceae family which has been used for various medicinal purposes for centuries, especially in Europe and only more recently has been proposed as a forage plant. The leaf of plantain is highly palatable for grazing animals, providing mineral-rich forage. Recently two productive upright cultivars of plantain have been bred and introduced, Grasslands Lancelot and the more erect winter active Ceres Tonic. Plantain grows moderately in winter but its main growth periods beings in spring and autumn with opportunistic summer growth. Although it reveals suitable winter survival in natural conditions, but there is not a lot of information about cold tolerance of this plant. So it is important to recognize the freeze tolerance of narrow leaf plantain for successful planting and utilization in cold regions such as Mashhad in Khorasan Razavi Province (Northeast of Iran. Determining LT50 point or critical temperature for survival of plant is the most reliable and simple method for evaluating cold tolerance of plants. Another reliable method for freeze tolerance of plants is estimation of temperature at which 50 % of dry matter reduces (RDMT50. This experiment was carried out to evaluate freeze tolerance of five ecotypes of Lancelot plantain according to the LT50su and RDMT50 indices. Materials and Methods In order to evaluate freeze tolerance of Lancelot plantain, a factorial experiment based on completely randomized design with three replications was carried out under controlled conditions at college of agriculture, Ferdowsi University of Mashhad. Five ecotypes of Lancelot plantain (Bojnourd, Kalat, Mashhad, Ghayen and Birjand after three months growth and hardening in natural environment were transferred to a Thermo gradient freezer on January 20th, 2012 and exposed to eight freezing temperatures (Zero, -3, -6, -9, -12, -15, -18

  15. Transient fault tolerant control for vehicle brake-by-wire systems

    International Nuclear Information System (INIS)

    Huang, Shuang; Zhou, Chunjie; Yang, Lili; Qin, Yuanqing; Huang, Xiongfeng; Hu, Bowen

    2016-01-01

    Brake-by-wire (BBW) systems that have no mechanical linkage between the brake pedal and the brake mechanism are expected to improve vehicle safety through better braking capability. However, transient faults in BBW systems can cause dangerous driving situations. Most existing research in this area focuses on the brake control mechanism, but very few studies try to solve the problem associated with transient fault propagation and evolution in the brake control system hierarchy. In this paper, a hierarchical transient fault tolerant scheme with embedded intelligence and resilient coordination for BBW system is proposed based on the analysis of transient fault propagation characteristics. In this scheme, most transient faults are tackled rapidly by a signature-based detection method at the node level, and the remaining transient faults, which cannot be detected directly at the node level and could degrade the system performance through fault propagation and evolution, are detected and recovered through function and structure models at the system level. To jointly accommodate these BBW transient faults at the system level, a sliding mode control algorithm and a task reallocation strategy are designed. A simulation platform based on Architecture Analysis and Design Language (AADL) is established to evaluate the task reallocation strategy, and a hardware-in-the-loop simulation is carried out to validate the proposed scheme systematically. Experimental results show the effectiveness of this new approach to BBW systems. - Highlights: • We propose a hierarchical transient fault tolerant scheme for BBW systems. • A sliding mode algorithm and a task strategy are designed to tackle transient fault. • The effectiveness of the scheme is verified in both simulation and HIL environments.

  16. Supervisory Fault Tolerant Control of the GTM UAV Using LPV Methods

    Directory of Open Access Journals (Sweden)

    Péni Tamás

    2015-03-01

    Full Text Available A multi-level reconfiguration framework is proposed for fault tolerant control of over-actuated aerial vehicles, where the levels indicate how much authority is given to the reconfiguration task. On the lowest, first level the fault is accommodated by modifying only the actuator/sensor configuration, so the fault remains hidden from the baseline controller. A dynamic reallocation scheme is applied on this level. The allocation mechanism exploits the actuator/sensor redundancy available on the aircraft. When the fault cannot be managed at the actuator/sensor level, the reconfiguration process has access to the baseline controller. Based on the LPV control framework, this is done by introducing fault-specific scheduling parameters. The baseline controller is designed to provide an acceptable performance level along all fault scenarios coded in these scheduling variables. The decision on which reconfiguration level has to be initiated in response to a fault is determined by a supervisor unit. The method is demonstrated on a full six-degrees-of-freedom nonlinear simulation model of the GTM UAV.

  17. Sensor fault-tolerant control for gear-shifting engaging process of automated manual transmission

    Science.gov (United States)

    Li, Liang; He, Kai; Wang, Xiangyu; Liu, Yahui

    2018-01-01

    Angular displacement sensor on the actuator of automated manual transmission (AMT) is sensitive to fault, and the sensor fault will disturb its normal control, which affects the entire gear-shifting process of AMT and results in awful riding comfort. In order to solve this problem, this paper proposes a method of fault-tolerant control for AMT gear-shifting engaging process. By using the measured current of actuator motor and angular displacement of actuator, the gear-shifting engaging load torque table is built and updated before the occurrence of the sensor fault. Meanwhile, residual between estimated and measured angular displacements is used to detect the sensor fault. Once the residual exceeds a determined fault threshold, the sensor fault is detected. Then, switch control is triggered, and the current observer and load torque table estimates an actual gear-shifting position to replace the measured one to continue controlling the gear-shifting process. Numerical and experiment tests are carried out to evaluate the reliability and feasibility of proposed methods, and the results show that the performance of estimation and control is satisfactory.

  18. A Hybrid Sensor Based Backstepping Control Approach with its Application to Fault-Tolerant Flight Control

    NARCIS (Netherlands)

    Sun, L.G.; De Visser, C.C.; Chu, Q.P.; Falkena, W.

    2013-01-01

    Recently, an incremental type sensor based backstepping (SBB) control approach, based on singular perturbation theory and Tikhonov’s theorem, has been proposed. This Lyapunov function based method uses measurements of control variables and less model knowledge, and it is not susceptible to the model

  19. An overview of the gene regulatory network controlling trichome development in the model plant, Arabidopsis

    Directory of Open Access Journals (Sweden)

    Sitakanta ePattanaik

    2014-06-01

    Full Text Available Trichomes are specialized epidermal cells located on aerial parts of plants and are associated with a wide array of biological processes. Trichomes protect plants from adverse conditions including UV light and herbivore attack and are also an important source of a number of phytochemicals. The simple unicellular trichomes of Arabidopsis serve as an excellent model to study molecular mechanism of cell differentiation and pattern formation in plants. The emerging picture suggests that the developmental process is controlled by a transcriptional network involving three major groups of transcription factors: the R2R3 MYB, basic helix-loop-helix (bHLH and WD40 repeat (WDR protein. These regulatory proteins form a trimeric activator complex that positively regulates trichome development. The single repeat R3 MYBs act as negative regulators of trichome development. They compete with the R2R3 MYBs to bind the bHLH factor and form a repressor complex. In addition to activator-repressor mechanism, a depletion mechanism may operate in parallel during trichome development. In this mechanism, the bHLH factor traps the WDR protein which results in depletion of WDR protein in neighboring cells. Consequently, the cells with high levels of bHLH and WDR proteins are developed into trichomes. A group of C2H2 zinc finger TFs has also been implicated in trichome development. Phytohormones, including gibberellins and jasmonic acid, play significant roles in this developmental process. Recently, microRNAs have been shown to be involved in trichome development. Furthermore, it has been demonstrated that the activities of the key regulatory proteins involved in trichome development are controlled by the 26S/ubiquitin proteasome system (UPS, highlighting the complexity of the regulatory network controlling this developmental process. To complement several excellent recent relevant reviews, this review focuses on the transcriptional network and hormonal interplay

  20. The regulatory control over radiation sources: the Brazilian experience and some lessons learned from industrial applications

    International Nuclear Information System (INIS)

    Costa, E.L.C.; Gomes, J.D.R.L.; Gomes, R.S.; Costa, M.L.L.; Thomé, Z.D.; Instituto Militar de Engenharia

    2017-01-01

    This study gives an overview of the activities of the National Commission of Nuclear Energy (CNEN), as the Brazilian nuclear regulatory authority. These activities are described, especially those related to management of orphan sources and radioactive material in scrap metal considering the actions already put into place by CNEN during the licensing and controlling of radioactive sources in the industry and other facilities. In Brazil, there is not yet an effective system for controlling the scrap metal and recycling industry, thus a coordinated approach to achieve a harmonized and effective response with the involvement of third parties is needed, especially the metal industries and ores facilities. These practices call for stringent regulatory control, in order to reduce the occurrence of orphan sources, and consequently, radioactive material appearing in scrap metal. Some challenges of managing the national radiation sources register systems will be discussed, in order to cover effectively all the radiation source history (in a 'from the cradle to the grave' basis), and the dynamic maintenance and update of these data. The main industrial applications considered in this work are those dealing with constant movement of sources all over the country, with geographical issues to be considered in the managing and controlling actions, such as gammagraphy and well-logging. This study aims to identify and promote good practices to prevent inadvertent diversion of radioactive material, taking into account existing international recommendations and some lessons learned in national level. (author)

  1. Deciphering the genetic regulatory code using an inverse error control coding framework.

    Energy Technology Data Exchange (ETDEWEB)

    Rintoul, Mark Daniel; May, Elebeoba Eni; Brown, William Michael; Johnston, Anna Marie; Watson, Jean-Paul

    2005-03-01

    We have found that developing a computational framework for reconstructing error control codes for engineered data and ultimately for deciphering genetic regulatory coding sequences is a challenging and uncharted area that will require advances in computational technology for exact solutions. Although exact solutions are desired, computational approaches that yield plausible solutions would be considered sufficient as a proof of concept to the feasibility of reverse engineering error control codes and the possibility of developing a quantitative model for understanding and engineering genetic regulation. Such evidence would help move the idea of reconstructing error control codes for engineered and biological systems from the high risk high payoff realm into the highly probable high payoff domain. Additionally this work will impact biological sensor development and the ability to model and ultimately develop defense mechanisms against bioagents that can be engineered to cause catastrophic damage. Understanding how biological organisms are able to communicate their genetic message efficiently in the presence of noise can improve our current communication protocols, a continuing research interest. Towards this end, project goals include: (1) Develop parameter estimation methods for n for block codes and for n, k, and m for convolutional codes. Use methods to determine error control (EC) code parameters for gene regulatory sequence. (2) Develop an evolutionary computing computational framework for near-optimal solutions to the algebraic code reconstruction problem. Method will be tested on engineered and biological sequences.

  2. The regulatory control over radiation sources: the Brazilian experience and some lessons learned from industrial applications

    Energy Technology Data Exchange (ETDEWEB)

    Costa, E.L.C.; Gomes, J.D.R.L.; Gomes, R.S.; Costa, M.L.L.; Thomé, Z.D., E-mail: evaldo@cnen.gov.br, E-mail: jlopes@cnen.gov.br, E-mail: rogeriog@cnen.gov.br, E-mail: mara@cnen.gov.br, E-mail: zielithome@gmail.com [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil). Diretoria de Radioproteção e Segurança Nuclear; Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Seção de Engenharia Nuclear

    2017-11-01

    This study gives an overview of the activities of the National Commission of Nuclear Energy (CNEN), as the Brazilian nuclear regulatory authority. These activities are described, especially those related to management of orphan sources and radioactive material in scrap metal considering the actions already put into place by CNEN during the licensing and controlling of radioactive sources in the industry and other facilities. In Brazil, there is not yet an effective system for controlling the scrap metal and recycling industry, thus a coordinated approach to achieve a harmonized and effective response with the involvement of third parties is needed, especially the metal industries and ores facilities. These practices call for stringent regulatory control, in order to reduce the occurrence of orphan sources, and consequently, radioactive material appearing in scrap metal. Some challenges of managing the national radiation sources register systems will be discussed, in order to cover effectively all the radiation source history (in a 'from the cradle to the grave' basis), and the dynamic maintenance and update of these data. The main industrial applications considered in this work are those dealing with constant movement of sources all over the country, with geographical issues to be considered in the managing and controlling actions, such as gammagraphy and well-logging. This study aims to identify and promote good practices to prevent inadvertent diversion of radioactive material, taking into account existing international recommendations and some lessons learned in national level. (author)

  3. Specific oral tolerance induction with raw hen's egg in children with very severe egg allergy: a randomized controlled trial.

    Science.gov (United States)

    Dello Iacono, Iride; Tripodi, Salvatore; Calvani, Mauro; Panetta, Valentina; Verga, Maria Carmela; Miceli Sopo, Stefano

    2013-02-01

    Treatment of severe egg allergy is avoidance of hen's egg (HE) and carrying self-injectable epinephrine. Specific oral tolerance induction (SOTI) seems a promising alternative treatment. However, some aspects of SOTI are still considered experimental. We evaluated the efficacy and safety of an original 6-month SOTI protocol in children with very severe HE allergy using raw HE emulsion. Twenty children (age range: 5-11 yr) were randomized equally into a SOTI treatment group and a control group. The treatment group started SOTI and underwent a second challenge 6 months later. Control children were kept on an egg-free diet for 6 months and then underwent a second challenge. After 6 months, 9/10 children of the SOTI group (90%) achieved partial tolerance (at least 10 ml, but <40 ml of raw HE emulsion, in a single dose) and 1 (10%) was able to tolerate only 5 ml (no tolerance). After 6 months, nine control children tested positive to the second challenge at a dose ≤0.9 ml of raw HE emulsion, and one reacted to 1.8 ml (SOTI vs. control group p<0.0001). All children in the SOTI group had side effects, but no child had a grade 5 reaction according to the Sampson grading. Six months of SOTI with raw HE emulsion resulted in partial tolerance, with regular intake, in a significant percentage of children with severe egg allergy. © 2012 John Wiley & Sons A/S.

  4. Data-based fault-tolerant control for affine nonlinear systems with actuator faults.

    Science.gov (United States)

    Xie, Chun-Hua; Yang, Guang-Hong

    2016-09-01

    This paper investigates the fault-tolerant control (FTC) problem for unknown nonlinear systems with actuator faults including stuck, outage, bias and loss of effectiveness. The upper bounds of stuck faults, bias faults and loss of effectiveness faults are unknown. A new data-based FTC scheme is proposed. It consists of the online estimations of the bounds and a state-dependent function. The estimations are adjusted online to compensate automatically the actuator faults. The state-dependent function solved by using real system data helps to stabilize the system. Furthermore, all signals in the resulting closed-loop system are uniformly bounded and the states converge asymptotically to zero. Compared with the existing results, the proposed approach is data-based. Finally, two simulation examples are provided to show the effectiveness of the proposed approach. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  5. A data-driven fault-tolerant control design of linear multivariable systems with performance optimization.

    Science.gov (United States)

    Li, Zhe; Yang, Guang-Hong

    2017-09-01

    In this paper, an integrated data-driven fault-tolerant control (FTC) design scheme is proposed under the configuration of the Youla parameterization for multiple-input multiple-output (MIMO) systems. With unknown system model parameters, the canonical form identification technique is first applied to design the residual observer in fault-free case. In faulty case, with online tuning of the Youla parameters based on the system data via the gradient-based algorithm, the fault influence is attenuated with system performance optimization. In addition, to improve the robustness of the residual generator to a class of system deviations, a novel adaptive scheme is proposed for the residual generator to prevent its over-activation. Simulation results of a two-tank flow system demonstrate the optimized performance and effect of the proposed FTC scheme. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Design of a fault-tolerant reversible control unit in molecular quantum-dot cellular automata

    Science.gov (United States)

    Bahadori, Golnaz; Houshmand, Monireh; Zomorodi-Moghadam, Mariam

    Quantum-dot cellular automata (QCA) is a promising emerging nanotechnology that has been attracting considerable attention due to its small feature size, ultra-low power consuming, and high clock frequency. Therefore, there have been many efforts to design computational units based on this technology. Despite these advantages of the QCA-based nanotechnologies, their implementation is susceptible to a high error rate. On the other hand, using the reversible computing leads to zero bit erasures and no energy dissipation. As the reversible computation does not lose information, the fault detection happens with a high probability. In this paper, first we propose a fault-tolerant control unit using reversible gates which improves on the previous design. The proposed design is then synthesized to the QCA technology and is simulated by the QCADesigner tool. Evaluation results indicate the performance of the proposed approach.

  7. Key Regulatory Issues for Digital Instrumentation and Control Systems at Nuclear Power Plants

    International Nuclear Information System (INIS)

    Korsah, Kofi; Wood, Richard Thomas

    2008-01-01

    To help reduce the uncertainty associated with application of digital instrumentation and controls (I and C) technology in nuclear power plants, the Nuclear Regulatory Commission (NRC) has issued six Interim Staff Guidance (ISG) documents that address the current regulatory positions on what are considered the significant digital I and C issues. These six documents address the following topics: Cyber Security, Diversity and Defense-in-Depth, Risk Informed Digital I and C Regulation, Communication issues, Human Factors and the Digital I and C Licensing Process (currently issued as Draft). After allowing for further refinement based on additional technical insight gathered by NRC staff through near-term research and detailed review of relevant experience, it is expected that updated positions ultimately will be incorporated into regulatory guides and staff review procedures. This paper presents an overview of the guidance provided by the NRC-issued ISGs on key technology considerations (i.e., the first five documents above) for safety-related digital I and C systems.

  8. A review of fault tolerant control strategies applied to proton exchange membrane fuel cell systems

    Science.gov (United States)

    Dijoux, Etienne; Steiner, Nadia Yousfi; Benne, Michel; Péra, Marie-Cécile; Pérez, Brigitte Grondin

    2017-08-01

    Fuel cells are powerful systems for power generation. They have a good efficiency and do not generate greenhouse gases. This technology involves a lot of scientific fields, which leads to the appearance of strongly inter-dependent parameters. This makes the system particularly hard to control and increases fault's occurrence frequency. These two issues call for the necessity to maintain the system performance at the expected level, even in faulty operating conditions. It is called "fault tolerant control" (FTC). The present paper aims to give the state of the art of FTC applied to the proton exchange membrane fuel cell (PEMFC). The FTC approach is composed of two parts. First, a diagnosis part allows the identification and the isolation of a fault; it requires a good a priori knowledge of all the possible faults. Then, a control part allows an optimal control strategy to find the best operating point to recover/mitigate the fault; it requires the knowledge of the degradation phenomena and their mitigation strategies.

  9. A radiation tolerance study of the ALICE TPC Readout Control Unit 2

    CERN Document Server

    Zhao, Chengxin; Balk, Helge; Alme, Johan

    2017-11-17

    ALICE is a general-purpose detector that is designed to study the physics of quark-gluon plasma. The Time Projection Chamber (TPC) is one of the major detectors of ALICE. The TPC electronics consists of 4356 Front-end cards (FECs), which are controlled by 216 Readout Control Units (RCU). Each RCU connects to between 18 and 25 FECs using a multi-drop bus. In LHC Run1, the Readout Control Unit 1 (RCU1) performed even better than specification. However, in Run2 the energy of colliding beams is increased from 8 TeV to 14 TeV (maximum value) and higher luminosity, which leads to larger event size and higher radiation load on the electronics. As a solution, the Readout Control Unit 2 (RCU2) is designed to provide faster readout speed and improved radiation tolerance with respect to the RCU1. The RCU2 is conceptually similar to the RCU1 and it reuses the existing infrastructure and readout architecture of the TPC electronics. However, the multi-drop bus is split into four branches from the two branches and the bandw...

  10. Efficacy and tolerability of intravenous morphine patient-controlled analgesia (PCA) in women undergoing cesarean delivery.

    Science.gov (United States)

    Andziak, Marta; Beta, Jarosław; Barwijuk, Michal; Issat, Tadeusz; Jakimiuk, Artur J

    2015-06-01

    The aim of the study was to evaluate analgesic efficacy and tolerability of patient-controlled analgesia (PCA) with intravenous morphine. Our observational study included 50 women who underwent a Misgav-Ladach or modified Misgav-Ladach cesarean section. Automated PCA infusion device (Medima S-PCA Syringe Pump, Medima, Krakow, Poland) was used for postoperative pain control. Time of morphine administration or initiation of intravenous patient-controlled analgesia (IV PCA) with morphine was recorded, as well as post-operative pain at rest assessed by a visual analogue scale (VAS). All patients were followed up for 24 hours after discharge from the operating room, taking into account patient records, worst pain score at rest, number of IV PCA attempts, and drug consumption. Median of total morphine doses used during the postoperative period was 42.9mg (IQR 35.6-48.5), with median infusion time of 687.0 min. (IQR 531.0-757.5). Pain severity and total drug consumption improved after the first 3 hours following cesarean delivery (p PCA attempts per patient was 33 (IQR: 24-37), with median of 11 placebo attempts (IQR: 3-27). Patient-controlled analgesia with morphine is an efficient and acceptable analgesic method in women undergoing cesarean section.

  11. Fault-tolerant control with mixed aerodynamic surfaces and RCS jets for hypersonic reentry vehicles

    Directory of Open Access Journals (Sweden)

    Jingjing He

    2017-04-01

    Full Text Available This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems (RCS under external disturbances and subject to actuator faults. Aerodynamic surfaces are treated as the primary actuator in normal situations, and they are driven by a continuous quadratic programming (QP allocator to generate torque commanded by a nonlinear adaptive feedback control law. When aerodynamic surfaces encounter faults, they may not be able to provide sufficient torque as commanded, and RCS jets are activated to augment the aerodynamic surfaces to compensate for insufficient torque. Partial loss of effectiveness and stuck faults are considered in this paper, and observers are designed to detect and identify the faults. Based on the fault identification results, an RCS control allocator using integer linear programming (ILP techniques is designed to determine the optimal combination of activated RCS jets. By treating the RCS control allocator as a quantization element, closed-loop stability with both continuous and quantized inputs is analyzed. Simulation results verify the effectiveness of the proposed method.

  12. Model checking optimal finite-horizon control for probabilistic gene regulatory networks.

    Science.gov (United States)

    Wei, Ou; Guo, Zonghao; Niu, Yun; Liao, Wenyuan

    2017-12-14

    Probabilistic Boolean networks (PBNs) have been proposed for analyzing external control in gene regulatory networks with incorporation of uncertainty. A context-sensitive PBN with perturbation (CS-PBNp), extending a PBN with context-sensitivity to reflect the inherent biological stability and random perturbations to express the impact of external stimuli, is considered to be more suitable for modeling small biological systems intervened by conditions from the outside. In this paper, we apply probabilistic model checking, a formal verification technique, to optimal control for a CS-PBNp that minimizes the expected cost over a finite control horizon. We first describe a procedure of modeling a CS-PBNp using the language provided by a widely used probabilistic model checker PRISM. We then analyze the reward-based temporal properties and the computation in probabilistic model checking; based on the analysis, we provide a method to formulate the optimal control problem as minimum reachability reward properties. Furthermore, we incorporate control and state cost information into the PRISM code of a CS-PBNp such that automated model checking a minimum reachability reward property on the code gives the solution to the optimal control problem. We conduct experiments on two examples, an apoptosis network and a WNT5A network. Preliminary experiment results show the feasibility and effectiveness of our approach. The approach based on probabilistic model checking for optimal control avoids explicit computation of large-size state transition relations associated with PBNs. It enables a natural depiction of the dynamics of gene regulatory networks, and provides a canonical form to formulate optimal control problems using temporal properties that can be automated solved by leveraging the analysis power of underlying model checking engines. This work will be helpful for further utilization of the advances in formal verification techniques in system biology.

  13. Infectious Tolerance

    OpenAIRE

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, ...

  14. The exemption of regulatory control for the management of low level radioactive wastes

    International Nuclear Information System (INIS)

    Ortiz, M.T.; Carboneras, P.

    1993-01-01

    A high number of wastes produced in different fields of science and technology, as well as nuclear power plants, contain a significant volume of byproducts contaminated with radioisotopes, having a very low radioactive level. This kind of wastes might be managed as ordinary wastes by conventional methods or even reused. In order to carry out this procedure, a new regulation exempting these products from the regulatory control normatives would be necessary. This paper analyzes the big advantages of introducing these exemptions (costs recycling, radioactive wastes minimization) and how they follow the recommendations of ICRP, IAEA, EC and NRC

  15. TransDetect Identifies a New Regulatory Module Controlling Phosphate Accumulation.

    Science.gov (United States)

    Pal, Sikander; Kisko, Mushtak; Dubos, Christian; Lacombe, Benoit; Berthomieu, Pierre; Krouk, Gabriel; Rouached, Hatem

    2017-10-01

    Identifying transcription factor (TFs) cooperation controlling target gene expression is still an arduous challenge. The accuracy of current methods at genome scale significantly drops with the increase in number of genes, which limits their applicability to more complex genomes, like animals and plants. Here, we developed an algorithm, TransDetect, able to predict TF combinations controlling the expression level of a given gene. TransDetect was used to identify novel TF modules regulating the expression of Arabidopsis ( Arabidopsis thaliana ) phosphate transporter PHO1;H3 comprising MYB15, MYB84, bHLH35, and ICE1. These TFs were confirmed to interact between themselves and with the PHO1;H3 promoter. Phenotypic and genetic analyses of TF mutants enable the organization of these four TFs and PHO1;H3 in a new gene regulatory network controlling phosphate accumulation in zinc-dependent manner. This demonstrates the potential of TransDetect to extract directionality in nondynamic transcriptomes and to provide a blueprint to identify gene regulatory network involved in a given biological process. © 2017 American Society of Plant Biologists. All Rights Reserved.

  16. The GBT-SCA, a radiation tolerant ASIC for detector control applications in SLHC experiments

    CERN Document Server

    Gabrielli, A; Kloukinas, K; Marchioro, A; Moreira, P; Ranieri, A; De Robertis, D

    2009-01-01

    This work describes the architecture of the GigaBit Transceiver – Slow Control Adapter (GBT–SCA) ASIC suitable for the control and monitoring applications of the embedded front-end electronics in the future SLHC experiments. The GBT–SCA is part the GBT chipset currently under development for the SLHC detector upgrades. It is designed for radiation tolerance and it will be fabricated in a commercial 130 nm CMOS technology. The paper discusses the GBT-SCA architecture, the data transfer protocol, the ASIC interfaces, and its integration with the GBT optical link. The GBT–SCA is one the components of the GBT system chipset. It is proposed for the future SLHC experiments and is designed to be configurable matching different front-end system requirements. The GBT-SCA is intended for the slow control and monitoring of the embedded front end electronics and implements a point-to-multi point connection between one GBT optical link ASIC and several front end ASICs. The GBT-SCA connects to a dedicated electrica...

  17. Sub-circuits of a gene regulatory network control a developmental epithelial-mesenchymal transition.

    Science.gov (United States)

    Saunders, Lindsay R; McClay, David R

    2014-04-01

    Epithelial-mesenchymal transition (EMT) is a fundamental cell state change that transforms epithelial to mesenchymal cells during embryonic development, adult tissue repair and cancer metastasis. EMT includes a complex series of intermediate cell state changes including remodeling of the basement membrane, apical constriction, epithelial de-adhesion, directed motility, loss of apical-basal polarity, and acquisition of mesenchymal adhesion and polarity. Transcriptional regulatory state changes must ultimately coordinate the timing and execution of these cell biological processes. A well-characterized gene regulatory network (GRN) in the sea urchin embryo was used to identify the transcription factors that control five distinct cell changes during EMT. Single transcription factors were perturbed and the consequences followed with in vivo time-lapse imaging or immunostaining assays. The data show that five different sub-circuits of the GRN control five distinct cell biological activities, each part of the complex EMT process. Thirteen transcription factors (TFs) expressed specifically in pre-EMT cells were required for EMT. Three TFs highest in the GRN specified and activated EMT (alx1, ets1, tbr) and the 10 TFs downstream of those (tel, erg, hex, tgif, snail, twist, foxn2/3, dri, foxb, foxo) were also required for EMT. No single TF functioned in all five sub-circuits, indicating that there is no EMT master regulator. Instead, the resulting sub-circuit topologies suggest EMT requires multiple simultaneous regulatory mechanisms: forward cascades, parallel inputs and positive-feedback lock downs. The interconnected and overlapping nature of the sub-circuits provides one explanation for the seamless orchestration by the embryo of cell state changes leading to successful EMT.

  18. Finite Time Fault Tolerant Control for Robot Manipulators Using Time Delay Estimation and Continuous Nonsingular Fast Terminal Sliding Mode Control.

    Science.gov (United States)

    Van, Mien; Ge, Shuzhi Sam; Ren, Hongliang

    2016-04-28

    In this paper, a novel finite time fault tolerant control (FTC) is proposed for uncertain robot manipulators with actuator faults. First, a finite time passive FTC (PFTC) based on a robust nonsingular fast terminal sliding mode control (NFTSMC) is investigated. Be analyzed for addressing the disadvantages of the PFTC, an AFTC are then investigated by combining NFTSMC with a simple fault diagnosis scheme. In this scheme, an online fault estimation algorithm based on time delay estimation (TDE) is proposed to approximate actuator faults. The estimated fault information is used to detect, isolate, and accommodate the effect of the faults in the system. Then, a robust AFTC law is established by combining the obtained fault information and a robust NFTSMC. Finally, a high-order sliding mode (HOSM) control based on super-twisting algorithm is employed to eliminate the chattering. In comparison to the PFTC and other state-of-the-art approaches, the proposed AFTC scheme possess several advantages such as high precision, strong robustness, no singularity, less chattering, and fast finite-time convergence due to the combined NFTSMC and HOSM control, and requires no prior knowledge of the fault due to TDE-based fault estimation. Finally, simulation results are obtained to verify the effectiveness of the proposed strategy.

  19. Transcriptomic variation among six Arabidopsis thaliana accessions identified several novel genes controlling aluminium tolerance.

    Science.gov (United States)

    Kusunoki, Kazutaka; Nakano, Yuki; Tanaka, Keisuke; Sakata, Yoichi; Koyama, Hiroyuki; Kobayashi, Yuriko

    2017-02-01

    Differences in the expression levels of aluminium (Al) tolerance genes are a known determinant of Al tolerance among plant varieties. We combined transcriptomic analysis of six Arabidopsis thaliana accessions with contrasting Al tolerance and a reverse genetic approach to identify Al-tolerance genes responsible for differences in Al tolerance between accession groups. Gene expression variation increased in the signal transduction process under Al stress and in growth-related processes in the absence of stress. Co-expression analysis and promoter single nucleotide polymorphism searching suggested that both trans-acting polymorphisms of Al signal transduction pathway and cis-acting polymorphisms in the promoter sequences caused the variations in gene expression associated with Al tolerance. Compared with the wild type, Al sensitivity increased in T-DNA knockout (KO) lines for five genes, including TARGET OF AVRB OPERATION1 (TAO1) and an unannotated gene (At5g22530). These were identified from 53 Al-inducible genes showing significantly higher expression in tolerant accessions than in sensitive accessions. These results indicate that the difference in transcriptional signalling is partly associated with the natural variation in Al tolerance in Arabidopsis. Our study also demonstrates the feasibility of comparative transcriptome analysis by using natural genetic variation for the identification of genes responsible for Al stress tolerance. © 2016 John Wiley & Sons Ltd.

  20. Redundant and fault-tolerant algorithms for real-time measurement and control systems for weapon equipment.

    Science.gov (United States)

    Li, Dan; Hu, Xiaoguang

    2017-03-01

    Because of the high availability requirements from weapon equipment, an in-depth study has been conducted on the real-time fault-tolerance of the widely applied Compact PCI (CPCI) bus measurement and control system. A redundancy design method that uses heartbeat detection to connect the primary and alternate devices has been developed. To address the low successful execution rate and relatively large waste of time slices in the primary version of the task software, an improved algorithm for real-time fault-tolerant scheduling is proposed based on the Basic Checking available time Elimination idle time (BCE) algorithm, applying a single-neuron self-adaptive proportion sum differential (PSD) controller. The experimental validation results indicate that this system has excellent redundancy and fault-tolerance, and the newly developed method can effectively improve the system availability. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  1. An improved fault-tolerant control scheme for PWM inverter-fed induction motor-based EVs.

    Science.gov (United States)

    Tabbache, Bekheïra; Benbouzid, Mohamed; Kheloui, Abdelaziz; Bourgeot, Jean-Matthieu; Mamoune, Abdeslam

    2013-11-01

    This paper proposes an improved fault-tolerant control scheme for PWM inverter-fed induction motor-based electric vehicles. The proposed strategy deals with power switch (IGBTs) failures mitigation within a reconfigurable induction motor control. To increase the vehicle powertrain reliability regarding IGBT open-circuit failures, 4-wire and 4-leg PWM inverter topologies are investigated and their performances discussed in a vehicle context. The proposed fault-tolerant topologies require only minimum hardware modifications to the conventional off-the-shelf six-switch three-phase drive, mitigating the IGBTs failures by specific inverter control. Indeed, the two topologies exploit the induction motor neutral accessibility for fault-tolerant purposes. The 4-wire topology uses then classical hysteresis controllers to account for the IGBT failures. The 4-leg topology, meanwhile, uses a specific 3D space vector PWM to handle vehicle requirements in terms of size (DC bus capacitors) and cost (IGBTs number). Experiments on an induction motor drive and simulations on an electric vehicle are carried-out using a European urban driving cycle to show that the proposed fault-tolerant control approach is effective and provides a simple configuration with high performance in terms of speed and torque responses. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  2. Control technologies for soil vapor extraction at petroleum hydrocarbon impacted sites -- Regulatory challenges to system operations

    International Nuclear Information System (INIS)

    Cacossa, K.F.; Campbell, G.E.; Devine, K.

    1995-01-01

    Soil vapor extraction (SVE) is frequently used to remediate soils impacted by petroleum hydrocarbons. Four technologies have proven to be viable methods to control the off-gas emissions from SVE systems, namely, internal combustion, thermal oxidation, catalytic oxidation, and granular activated carbon adsorption. The optimal range of influent vapor concentrations for system operation differs for each of the technologies. Over the past several years the authors have worked proactively with the state regulatory community to develop general, all inclusive air pollution control permits which allow for the potential use of all four technologies over the life of the permit. Private industry has similarly worked with the state regulators to develop a less labor intensive sampling/monitoring procedure. Actual system performances, which were monitored using summa canisters and field equipment, provided the basis for the new procedure. System performance data indicated that field sampling with portable hydrocarbon analyzers, such as flame ionization detectors (FID), was preferable over the use of summa canister sampling. In addition, to reduce the costs associated with the analysis of samples, the new SVE monitoring protocol also reduced the number of system monitoring visits. These reductions equated into a cost effective, yet environmentally sound SVE system monitoring programs. Finally, the authors have worked with the regulatory community to establish permit limitations which allow operational flexibility

  3. Neural correlates of preparatory and regulatory control over positive and negative emotion.

    Science.gov (United States)

    Seo, Dongju; Olman, Cheryl A; Haut, Kristen M; Sinha, Rajita; MacDonald, Angus W; Patrick, Christopher J

    2014-04-01

    This study used functional magnetic resonance imaging to investigate brain activation during preparatory and regulatory control while participants (N = 24) were instructed either to simply view or decrease their emotional response to, pleasant, neutral or unpleasant pictures. A main effect of emotional valence on brain activity was found in the right precentral gyrus, with greater activation during positive than negative emotion regulation. A main effect of regulation phase was evident in the bilateral anterior prefrontal cortex (PFC), precuneus, posterior cingulate cortex, right putamen and temporal and occipital lobes, with greater activity in these regions during preparatory than regulatory control. A valence X regulation interaction was evident in regions of ventromedial PFC and anterior cingulate cortex, reflecting greater activation while regulating negative than positive emotion, but only during active emotion regulation (not preparation). Conjunction analyses revealed common brain regions involved in differing types of emotion regulation including selected areas of left lateral PFC, inferior parietal lobe, temporal lobe, right cerebellum and bilateral dorsomedial PFC. The right lateral PFC was additionally activated during the modulation of both positive and negative valence. Findings demonstrate significant modulation of brain activity during both preparation for, and active regulation of positive and negative emotional states.

  4. Regulatory perspective on digital instrumentation and control systems for future advanced nuclear power plants

    International Nuclear Information System (INIS)

    Chiramal, M.

    1993-01-01

    This paper deals with the question of using digital technology in instrumentation and control systems for modern nuclear power reactors. The general opinion in the industry and among NRC staff is that such technology provides the opportunity for enhanced safety and reliable reactor operations. The major concern is the safe application of this technology so as to avoid common mode or common cause failures in systems. There are great differences between digital and analog system components. SECY-91-292 identifies some general regulatory concerns with regard to digital systems. There is clearly a lack of adequate regulatory direction on the application of digital equipment at this time, but the issue is being addressed by the industry, outside experts, and NRC staff. NRC staff presents a position on the issue of defense-in-depth and diversity with regard to insuring plant safety. Independent manual controls and readouts must be available to allow safe shutdown and monitoring of the plant in the event of safety system failures

  5. The Health and Safety Executive's regulatory framework for control of nuclear criticality safety

    International Nuclear Information System (INIS)

    Smith, K.; Simister, D.N.

    1991-01-01

    In the United Kingdom the Health and Safety at Work Act, 1974 is the main legal instrument under which risks to people from work activities are controlled. Certain sections of the Nuclear Installations Act, 1965 which deal with the licensing of nuclear sites and the regulatory control of risks arising from them, including the risk from accidental criticality, are relevant statutory provisions of the Health and Safety at Work Act. The responsibility for safety rests with the operator who has to make and implement arrangements to prevent accidental criticality. The adequacy of these arrangements must be demonstrated in a safety case to the regulatory authorities. Operators are encouraged to treat each plant on its own merits and develop the safety case accordingly. The Nuclear Installations Inspectorate (NII), for its part, assesses the adequacy of the operator's safety case against the industry's own standards and criteria, but more particularly against the NII's safety assessment principles and guides, and international standards. Risks should be made as low as reasonably practicable. Generally, the NII seeks improvements in safety using an enforcement policy which operates at a number of levels, ranging from persuasion through discussion to the ultimate deterrent of withdrawal of a site licence. This paper describes the role of the NII, which includes a specialist criticality expertise, within the Health and Safety Executive, in regulating the nuclear sites from the criticality safety viewpoint. (Author)

  6. Energy reduction for a dual circuit cooling water system using advanced regulatory control

    International Nuclear Information System (INIS)

    Muller, C.J.; Craig, I.K.

    2016-01-01

    Highlights: • Potentially reduce energy required by a dual circuit cooling water system by 30%. • Accomplished using an advanced regulatory control and switching strategy. • No formal process model is required. • Can be implemented on control system hardware commonly used in industry. - Abstract: Various process utilities are used in the petrochemical industry as auxiliary variables to facilitate the addition/removal of energy to/from the process, power process equipment and inhibit unwanted reaction. Optimisation activities usually focus on the process itself or on the utility consumption though the generation and distribution of these utilities are often overlooked in this regard. Many utilities are prepared or generated far from the process plant and have to be transported or transmitted, giving rise to more losses and potential inefficiencies. To illustrate the potential benefit of utility optimisation, this paper explores the control of a dual circuit cooling water system with focus on energy reduction subject process constraints. This is accomplished through the development of an advanced regulatory control (ARC) and switching strategy which does not require the development of a system model, only rudimentary knowledge of the behaviour of the process and system constraints. The novelty of this manuscript lies in the fact that it demonstrates that significant energy savings can be obtained by applying ARC to a process utility containing both discrete and continuous dynamics. Furthermore, the proposed ARC strategy does not require a plant model, uses only existing plant equipment, and can be implemented on control system hardware commonly used in industry. The simulation results indicate energy saving potential in the region of 30% on the system under investigation.

  7. Core Transcriptional Regulatory Circuit Controlled by the TAL1 Complex in Human T Cell Acute Lymphoblastic Leukemia

    OpenAIRE

    Sanda, Takaomi; Lawton, Lee N.; Barrasa, M. Inmaculada; Fan, Zi Peng; Kohlhammer, Holger; Gutierrez, Alejandro; Ma, Wenxue; Tatarek, Jessica; Ahn, Yebin; Kelliher, Michelle A.; Jamieson, Catriona H.M.; Staudt, Louis M.; Young, Richard A.; Look, A. Thomas

    2012-01-01

    The oncogenic transcription factor TAL1/SCL is aberrantly expressed in over 40% of cases of human T-cell acute lymphoblastic leukemia (T-ALL), emphasizing its importance in the molecular pathogenesis of T-ALL. Here we identify the core transcriptional regulatory circuit controlled by TAL1 and its regulatory partners HEB, E2A, LMO1/2, GATA3 and RUNX1. We show that TAL1 forms a positive interconnected auto-regulatory loop with GATA3 and RUNX1, and that the TAL1 complex directly activates the MY...

  8. Mast cell degranulation breaks peripheral tolerance.

    Science.gov (United States)

    de Vries, V C; Wasiuk, A; Bennett, K A; Benson, M J; Elgueta, R; Waldschmidt, T J; Noelle, R J

    2009-10-01

    Mast cells (MC) have been shown to mediate regulatory T-cell (T(reg))-dependent, peripheral allograft tolerance in both skin and cardiac transplants. Furthermore, T(reg) have been implicated in mitigating IgE-mediated MC degranulation, establishing a dynamic, reciprocal relationship between MC and T(reg) in controlling inflammation. In an allograft tolerance model, it is now shown that intragraft or systemic MC degranulation results in the transient loss of T(reg) suppressor activities with the acute, T-cell dependent rejection of established, tolerant allografts. Upon degranulation, MC mediators can be found in the skin, T(reg) rapidly leave the graft, MC accumulate in the regional lymph node and the T(reg) are impaired in the expression of suppressor molecules. Such a dramatic reversal of T(reg) function and tissue distribution by MC degranulation underscores how allergy may causes the transient breakdown of peripheral tolerance and episodes of acute T-cell inflammation.

  9. Output Information Based Fault-Tolerant Iterative Learning Control for Dual-Rate Sampling Process with Disturbances and Output Delay

    Directory of Open Access Journals (Sweden)

    Hongfeng Tao

    2018-01-01

    Full Text Available For a class of single-input single-output (SISO dual-rate sampling processes with disturbances and output delay, this paper presents a robust fault-tolerant iterative learning control algorithm based on output information. Firstly, the dual-rate sampling process with output delay is transformed into discrete system in state-space model form with slow sampling rate without time delay by using lifting technology; then output information based fault-tolerant iterative learning control scheme is designed and the control process is turned into an equivalent two-dimensional (2D repetitive process. Moreover, based on the repetitive process stability theory, the sufficient conditions for the stability of system and the design method of robust controller are given in terms of linear matrix inequalities (LMIs technique. Finally, the flow control simulations of two flow tanks in series demonstrate the feasibility and effectiveness of the proposed method.

  10. Specific interactions between DNA and regulatory protein controlled by ligand-binding: Ab initio molecular simulation

    International Nuclear Information System (INIS)

    Matsushita, Y.; Murakawa, T.; Shimamura, K.; Oishi, M.; Ohyama, T.; Kurita, N.

    2015-01-01

    The catabolite activator protein (CAP) is one of the regulatory proteins controlling the transcription mechanism of gene. Biochemical experiments elucidated that the complex of CAP with cyclic AMP (cAMP) is indispensable for controlling the mechanism, while previous molecular simulations for the monomer of CAP+cAMP complex revealed the specific interactions between CAP and cAMP. However, the effect of cAMP-binding to CAP on the specific interactions between CAP and DNA is not elucidated at atomic and electronic levels. We here considered the ternary complex of CAP, cAMP and DNA in solvating water molecules and investigated the specific interactions between them at atomic and electronic levels using ab initio molecular simulations based on classical molecular dynamics and ab initio fragment molecular orbital methods. The results highlight the important amino acid residues of CAP for the interactions between CAP and cAMP and between CAP and DNA

  11. Specific interactions between DNA and regulatory protein controlled by ligand-binding: Ab initio molecular simulation

    Energy Technology Data Exchange (ETDEWEB)

    Matsushita, Y., E-mail: kurita@cs.tut.ac.jp; Murakawa, T., E-mail: kurita@cs.tut.ac.jp; Shimamura, K., E-mail: kurita@cs.tut.ac.jp; Oishi, M., E-mail: kurita@cs.tut.ac.jp; Ohyama, T., E-mail: kurita@cs.tut.ac.jp; Kurita, N., E-mail: kurita@cs.tut.ac.jp [Department of Computer Science and Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi, Aichi, 441-8580 (Japan)

    2015-02-27

    The catabolite activator protein (CAP) is one of the regulatory proteins controlling the transcription mechanism of gene. Biochemical experiments elucidated that the complex of CAP with cyclic AMP (cAMP) is indispensable for controlling the mechanism, while previous molecular simulations for the monomer of CAP+cAMP complex revealed the specific interactions between CAP and cAMP. However, the effect of cAMP-binding to CAP on the specific interactions between CAP and DNA is not elucidated at atomic and electronic levels. We here considered the ternary complex of CAP, cAMP and DNA in solvating water molecules and investigated the specific interactions between them at atomic and electronic levels using ab initio molecular simulations based on classical molecular dynamics and ab initio fragment molecular orbital methods. The results highlight the important amino acid residues of CAP for the interactions between CAP and cAMP and between CAP and DNA.

  12. Fault Diagnosis and Fault-tolerant Control of Modular Multi-level Converter High-voltage DC System

    DEFF Research Database (Denmark)

    Liu, Hui; Ma, Ke; Wang, Chao

    2016-01-01

    of failures and lower the reliability of the MMC-HVDC system. Therefore, research on the fault diagnosis and fault-tolerant control of MMC-HVDC system is of great significance in order to enhance the reliability of the system. This paper provides a comprehensive review of fault diagnosis and fault handling...

  13. Eating on impulse: Implicit attitudes, self-regulatory resources, and trait self-control as determinants of food consumption.

    Science.gov (United States)

    Wang, Yan; Wang, Lei; Cui, Xianghua; Fang, Yuan; Chen, Qianqiu; Wang, Ya; Qiang, Yao

    2015-12-01

    Self-regulatory resources and trait self-control have been found to moderate the impulse-behavior relationship. The current study investigated whether the interaction of self-regulatory resources and trait self-control moderates the association between implicit attitudes and food consumption. One hundred twenty female participants were randomly assigned to either a depletion condition in which their self-regulatory resources were reduced or a no-depletion condition. Participants' implicit attitudes for chocolate were measured with the Single Category Implicit Association Test and self-report measures of trait self-control were collected. The dependent variable was chocolate consumption in an ostensible taste and rate task. Implicit attitudes predicted chocolate consumption in depleted participants but not in non-depleted participants. However, this predictive power of implicit attitudes on eating in depleted condition disappeared in participants with high trait self-control. Thus, trait self-control and self-regulatory resources interact to moderate the prediction of implicit attitude on eating behavior. Results suggest that high trait self-control buffers the effect of self-regulatory depletion on impulsive eating. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Breaking Tolerance to Thyroid Antigens: Changing Concepts in Thyroid Autoimmunity

    Science.gov (United States)

    Rapoport, Basil

    2014-01-01

    Thyroid autoimmunity involves loss of tolerance to thyroid proteins in genetically susceptible individuals in association with environmental factors. In central tolerance, intrathymic autoantigen presentation deletes immature T cells with high affinity for autoantigen-derived peptides. Regulatory T cells provide an alternative mechanism to silence autoimmune T cells in the periphery. The TSH receptor (TSHR), thyroid peroxidase (TPO), and thyroglobulin (Tg) have unusual properties (“immunogenicity”) that contribute to breaking tolerance, including size, abundance, membrane association, glycosylation, and polymorphisms. Insight into loss of tolerance to thyroid proteins comes from spontaneous and induced animal models: 1) intrathymic expression controls self-tolerance to the TSHR, not TPO or Tg; 2) regulatory T cells are not involved in TSHR self-tolerance and instead control the balance between Graves' disease and thyroiditis; 3) breaking TSHR tolerance involves contributions from major histocompatibility complex molecules (humans and induced mouse models), TSHR polymorphism(s) (humans), and alternative splicing (mice); 4) loss of tolerance to Tg before TPO indicates that greater Tg immunogenicity vs TPO dominates central tolerance expectations; 5) tolerance is induced by thyroid autoantigen administration before autoimmunity is established; 6) interferon-α therapy for hepatitis C infection enhances thyroid autoimmunity in patients with intact immunity; Graves' disease developing after T-cell depletion reflects reconstitution autoimmunity; and 7) most environmental factors (including excess iodine) “reveal,” but do not induce, thyroid autoimmunity. Micro-organisms likely exert their effects via bystander stimulation. Finally, no single mechanism explains the loss of tolerance to thyroid proteins. The goal of inducing self-tolerance to prevent autoimmune thyroid disease will require accurate prediction of at-risk individuals together with an antigen

  15. Smokers and non-smokers talk about regulatory options in tobacco control.

    Science.gov (United States)

    Carter, Stacy M; Chapman, Simon

    2006-10-01

    Community members are occasionally polled about tobacco control policies, but are rarely given opportunities to elaborate on their views. We examined laypeople's conversations to understand how 11 regulatory options were supported or opposed in interactions. Qualitative design; purposive quota sampling; data collection via focus groups. Three locations in Sydney, Australia. 63 smokers and 75 non-smokers, men and women, from three age groups (18-24, 35-44, 55-64 years), recruited primarily via telephone. Semi-structured question route; data managed in NVivo; responses compared between groups. Laypeople rejected some regulatory proposals and certain arguments about taxation and the cost of cessation treatments. Protecting children and hypothecating tobacco excise for health education and care were highly acceptable. Plain packaging, banning retail displays and youth smoking prevention received qualified support. Bans on political donations from tobacco corporations were popular in principle but considered logistically fraught. Smokers asked for better cessation assistance and were curious about cigarette ingredients. Justice was an important evaluative principle. Support was often conditional and unresolved arguments frequent. We present both sides of these conflicts and the ways in which policies were legitimised or de-legitimised in conversation. Simple measures of agreement used in polls may obscure the complexity of community responses to tobacco policy. Support was frequently present but contested; some arguments that seem self-evident to advocates were not so to participants. The detailed understanding of laypeople's responses provided through qualitative methods may help frame proposals and arguments to meet concerns about justice, effectiveness and feasibility.

  16. Enhancing water stress tolerance improves fitness in biological control strains of Lactobacillus plantarum in plant environments.

    Science.gov (United States)

    Daranas, Núria; Badosa, Esther; Francés, Jesús; Montesinos, Emilio; Bonaterra, Anna

    2018-01-01

    Lactobacillus plantarum strains PM411 and TC92 can efficiently control bacterial plant diseases, but their fitness on the plant surface is limited under unfavourable low relative humidity (RH) conditions. To increase tolerance of these strains to water stress, an adaptive strategy was used consisting of hyperosmotic and acidic conditions during growth. Adapted cells had higher survival rates under desiccation than non-adapted cells. Transcript levels and patterns of general stress-related genes increased immediately after the combined-stress adaptation treatment, and remained unaltered or repressed during the desiccation challenge. However, there were differences between strains in the transcription patterns that were in agreement with a better performance of adapted cells of PM411 than TC92 in plant surfaces under low RH environmental conditions. The combined-stress adaptation treatment increased the survival of PM411 cells consistently in different plant hosts in the greenhouse and under field conditions. Stress-adapted cells of PM411 had similar biocontrol potential against bacterial plant pathogens than non-adapted cells, but with less variability within experiments.

  17. Enhancing water stress tolerance improves fitness in biological control strains of Lactobacillus plantarum in plant environments.

    Directory of Open Access Journals (Sweden)

    Núria Daranas

    Full Text Available Lactobacillus plantarum strains PM411 and TC92 can efficiently control bacterial plant diseases, but their fitness on the plant surface is limited under unfavourable low relative humidity (RH conditions. To increase tolerance of these strains to water stress, an adaptive strategy was used consisting of hyperosmotic and acidic conditions during growth. Adapted cells had higher survival rates under desiccation than non-adapted cells. Transcript levels and patterns of general stress-related genes increased immediately after the combined-stress adaptation treatment, and remained unaltered or repressed during the desiccation challenge. However, there were differences between strains in the transcription patterns that were in agreement with a better performance of adapted cells of PM411 than TC92 in plant surfaces under low RH environmental conditions. The combined-stress adaptation treatment increased the survival of PM411 cells consistently in different plant hosts in the greenhouse and under field conditions. Stress-adapted cells of PM411 had similar biocontrol potential against bacterial plant pathogens than non-adapted cells, but with less variability within experiments.

  18. Comparing genomes to computer operating systems in terms of the topology and evolution of their regulatory control networks.

    Science.gov (United States)

    Yan, Koon-Kiu; Fang, Gang; Bhardwaj, Nitin; Alexander, Roger P; Gerstein, Mark

    2010-05-18

    The genome has often been called the operating system (OS) for a living organism. A computer OS is described by a regulatory control network termed the call graph, which is analogous to the transcriptional regulatory network in a cell. To apply our firsthand knowledge of the architecture of software systems to understand cellular design principles, we present a comparison between the transcriptional regulatory network of a well-studied bacterium (Escherichia coli) and the call graph of a canonical OS (Linux) in terms of topology and evolution. We show that both networks have a fundamentally hierarchical layout, but there is a key difference: The transcriptional regulatory network possesses a few global regulators at the top and many targets at the bottom; conversely, the call graph has many regulators controlling a small set of generic functions. This top-heavy organization leads to highly overlapping functional modules in the call graph, in contrast to the relatively independent modules in the regulatory network. We further develop a way to measure evolutionary rates comparably between the two networks and explain this difference in terms of network evolution. The process of biological evolution via random mutation and subsequent selection tightly constrains the evolution of regulatory network hubs. The call graph, however, exhibits rapid evolution of its highly connected generic components, made possible by designers' continual fine-tuning. These findings stem from the design principles of the two systems: robustness for biological systems and cost effectiveness (reuse) for software systems.

  19. Exemption of radiation sources and practices from regulatory control: Interim report

    International Nuclear Information System (INIS)

    1987-01-01

    This document is an interim report on progress at the IAEA on exemption principles and their application to low-level radioactive waste disposal. In the first part of the document the general principles for the exemption of radiation sources and practices from regulatory control are described. The exempt quantities of low-level radioactive wastes for disposal to municipal landfill or by incineration including methods for their derivation and generic values are contained in the second part of the document. In the appendices the individual effective dose equivalents and committed effective dose equivalents by pathway for waste concentrations of 1 Bq.g -1 and some quoted limits from the literature on dust concentrations at the outlet of municipal waste incinerators are estimated

  20. Nuclear Forensic Science: Analysis of Nuclear Material Out of Regulatory Control

    Science.gov (United States)

    Kristo, Michael J.; Gaffney, Amy M.; Marks, Naomi; Knight, Kim; Cassata, William S.; Hutcheon, Ian D.

    2016-06-01

    Nuclear forensic science seeks to identify the origin of nuclear materials found outside regulatory control. It is increasingly recognized as an integral part of a robust nuclear security program. This review highlights areas of active, evolving research in nuclear forensics, with a focus on analytical techniques commonly employed in Earth and planetary sciences. Applications of nuclear forensics to uranium ore concentrates (UOCs) are discussed first. UOCs have become an attractive target for nuclear forensic researchers because of the richness in impurities compared to materials produced later in the fuel cycle. The development of chronometric methods for age dating nuclear materials is then discussed, with an emphasis on improvements in accuracy that have been gained from measurements of multiple radioisotopic systems. Finally, papers that report on casework are reviewed, to provide a window into current scientific practice.

  1. Interaction mode between catalytic and regulatory subunits in glucosidase II involved in ER glycoprotein quality control.

    Science.gov (United States)

    Satoh, Tadashi; Toshimori, Takayasu; Noda, Masanori; Uchiyama, Susumu; Kato, Koichi

    2016-11-01

    The glycoside hydrolase family 31 (GH31) α-glucosidases play vital roles in catabolic and regulated degradation, including the α-subunit of glucosidase II (GIIα), which catalyzes trimming of the terminal glucose residues of N-glycan in glycoprotein processing coupled with quality control in the endoplasmic reticulum (ER). Among the known GH31 enzymes, only GIIα functions with its binding partner, regulatory β-subunit (GIIβ), which harbors a lectin domain for substrate recognition. Although the structural data have been reported for GIIα and the GIIβ lectin domain, the interaction mode between GIIα and GIIβ remains unknown. Here, we determined the structure of a complex formed between GIIα and the GIIα-binding domain of GIIβ, thereby providing a structural basis underlying the functional extension of this unique GH31 enzyme. © 2016 The Protein Society.

  2. Media ion composition controls regulatory and virulence response of Salmonella in spaceflight.

    Directory of Open Access Journals (Sweden)

    James W Wilson

    Full Text Available The spaceflight environment is relevant to conditions encountered by pathogens during the course of infection and induces novel changes in microbial pathogenesis not observed using conventional methods. It is unclear how microbial cells sense spaceflight-associated changes to their growth environment and orchestrate corresponding changes in molecular and physiological phenotypes relevant to the infection process. Here we report that spaceflight-induced increases in Salmonella virulence are regulated by media ion composition, and that phosphate ion is sufficient to alter related pathogenesis responses in a spaceflight analogue model. Using whole genome microarray and proteomic analyses from two independent Space Shuttle missions, we identified evolutionarily conserved molecular pathways in Salmonella that respond to spaceflight under all media compositions tested. Identification of conserved regulatory paradigms opens new avenues to control microbial responses during the infection process and holds promise to provide an improved understanding of human health and disease on Earth.

  3. Implementation of a Fault Tolerant Control Unit within an FPGA for Space Applications

    National Research Council Canada - National Science Library

    Perez Casanova, Gaspar M

    2006-01-01

    .... The Configurable Fault Tolerant Processor (CFTP) developed at the Naval Postgraduate School (NPS) was intended to work as a platform for the implementation and testing of designs and experiments for space applications...

  4. A distributed fault tolerant architecture for nuclear reactor control and safety functions

    International Nuclear Information System (INIS)

    Hecht, M.; Agron, J.; Hochhauser, S.

    1989-01-01

    This paper reports on a fault tolerance architecture that provides tolerance to a broad scope of hardware, software, and communications faults which is being developed. This architecture relies on widely commercially available operating systems, local area networks, and software standards. Thus, development time is significantly shortened, and modularity allows for continuous and inexpensive system enhancement throughout the expected 20- year life. The fault containment and parallel processing capabilites of computers network are being exploited to provide a high performance, high availability network capable of tolerating a broad scope of hardware software, and operating system faults. The system can tolerate all but one known (and avoidable) single fault, two known and avoidable dual faults, and will detect all higher order fault sequences and provide diagnostics to allow for rapid manual recovery

  5. Chinese proprietary medicine in Singapore: regulatory control of toxic heavy metals and undeclared drugs.

    Science.gov (United States)

    Koh, H L; Woo, S O

    2000-11-01

    Traditional Chinese medicine (TCM) is gaining popularity as a form of complementary and alternative medicine. Reports of efficacy of TCM are increasing in numbers. TCM includes both crude Chinese medicinal materials (plants, animal parts and minerals) and Chinese proprietary medicine (CPM) [final dosage forms]. Despite the belief that CPM and herbal remedies are of natural origin, unlike Western medicine, and are hence safe and without many adverse effects, there have been numerous reports of adverse effects associated with herbal remedies. Factors affecting the safety of herbal medicines include intrinsic toxicity, adulteration, substitution, contamination, misidentification, lack of standardisation, incorrect preparation and/or dosage and inappropriate labelling and/or advertising. Hence, new regulations on the control of CPM were enforced in Singapore with effect from 1 September 1999. These include licensing and labelling requirements, as well as control of microbial contamination. This article also reviews reports of excessive toxic heavy metals and undeclared drugs in CPM in Singapore between 1990 and 1997. The names, uses, toxic heavy metal or drug detected and the year of detection are tabulated. Information on the brand or manufacturer's name are provided whenever available. The public and healthcare professionals should be better informed of the basic concept of TCM and its usefulness, as well as the potential adverse effects associated with its use. Greater control over the safety and quality of CPM could be achieved through good manufacturing practice, regulatory control, research, education, reporting usage of Chinese medicine (as in drug history) as well as reporting of adverse events.

  6. Regulatory infrastructure for the control of radiation sources in the Africa region: Status, needs and programmes

    International Nuclear Information System (INIS)

    Skornik, K.

    2001-01-01

    In recent years, several African countries have taken steps towards creating or strengthening legal, administrative and technical mechanisms for the regulation and control of peaceful uses of nuclear technology, and towards improving the effectiveness and sustainability of radiation protection measures based on international standards. This stems from a growing awareness that a proper national infrastructure is a prerequisite for the implementation of safety standards to achieve and maintain the desired level of protection and safety, particularly in such sectors as public health and industry. Also, other issues of global and regional interest, such as the control of radiation sources, including the handling of hazardous waste, and response capabilities in the case of a radiological emergency, have contributed to a better perception of risks associated with deficiencies in or lack of adequate national radiation protection control mechanisms. Too often, however, this awareness has not been matched with adequate progress in the establishment of a regulatory framework for the control of radiation sources. This paper presents a summary of the current status of radiation protection infrastructure in all African Member States. On a background of still existing weaknesses and challenges, an overview of the Agency's response to assistance needs and programmes in this field is discussed. (author)

  7. Positive lists of cosmetic ingredients: Analytical methodology for regulatory and safety controls – A review

    International Nuclear Information System (INIS)

    Lores, Marta; Llompart, Maria; Alvarez-Rivera, Gerardo; Guerra, Eugenia; Vila, Marlene; Celeiro, Maria; Lamas, J. Pablo; Garcia-Jares, Carmen

    2016-01-01

    Cosmetic products placed on the market and their ingredients, must be safe under reasonable conditions of use, in accordance to the current legislation. Therefore, regulated and allowed chemical substances must meet the regulatory criteria to be used as ingredients in cosmetics and personal care products, and adequate analytical methodology is needed to evaluate the degree of compliance. This article reviews the most recent methods (2005–2015) used for the extraction and the analytical determination of the ingredients included in the positive lists of the European Regulation of Cosmetic Products (EC 1223/2009): comprising colorants, preservatives and UV filters. It summarizes the analytical properties of the most relevant analytical methods along with the possibilities of fulfilment of the current regulatory issues. The cosmetic legislation is frequently being updated; consequently, the analytical methodology must be constantly revised and improved to meet safety requirements. The article highlights the most important advances in analytical methodology for cosmetics control, both in relation to the sample pretreatment and extraction and the different instrumental approaches developed to solve this challenge. Cosmetics are complex samples, and most of them require a sample pretreatment before analysis. In the last times, the research conducted covering this aspect, tended to the use of green extraction and microextraction techniques. Analytical methods were generally based on liquid chromatography with UV detection, and gas and liquid chromatographic techniques hyphenated with single or tandem mass spectrometry; but some interesting proposals based on electrophoresis have also been reported, together with some electroanalytical approaches. Regarding the number of ingredients considered for analytical control, single analyte methods have been proposed, although the most useful ones in the real life cosmetic analysis are the multianalyte approaches. - Highlights:

  8. Positive lists of cosmetic ingredients: Analytical methodology for regulatory and safety controls – A review

    Energy Technology Data Exchange (ETDEWEB)

    Lores, Marta, E-mail: marta.lores@usc.es; Llompart, Maria; Alvarez-Rivera, Gerardo; Guerra, Eugenia; Vila, Marlene; Celeiro, Maria; Lamas, J. Pablo; Garcia-Jares, Carmen

    2016-04-07

    Cosmetic products placed on the market and their ingredients, must be safe under reasonable conditions of use, in accordance to the current legislation. Therefore, regulated and allowed chemical substances must meet the regulatory criteria to be used as ingredients in cosmetics and personal care products, and adequate analytical methodology is needed to evaluate the degree of compliance. This article reviews the most recent methods (2005–2015) used for the extraction and the analytical determination of the ingredients included in the positive lists of the European Regulation of Cosmetic Products (EC 1223/2009): comprising colorants, preservatives and UV filters. It summarizes the analytical properties of the most relevant analytical methods along with the possibilities of fulfilment of the current regulatory issues. The cosmetic legislation is frequently being updated; consequently, the analytical methodology must be constantly revised and improved to meet safety requirements. The article highlights the most important advances in analytical methodology for cosmetics control, both in relation to the sample pretreatment and extraction and the different instrumental approaches developed to solve this challenge. Cosmetics are complex samples, and most of them require a sample pretreatment before analysis. In the last times, the research conducted covering this aspect, tended to the use of green extraction and microextraction techniques. Analytical methods were generally based on liquid chromatography with UV detection, and gas and liquid chromatographic techniques hyphenated with single or tandem mass spectrometry; but some interesting proposals based on electrophoresis have also been reported, together with some electroanalytical approaches. Regarding the number of ingredients considered for analytical control, single analyte methods have been proposed, although the most useful ones in the real life cosmetic analysis are the multianalyte approaches. - Highlights:

  9. Retroviral vectors encoding ADA regulatory locus control region provide enhanced T-cell-specific transgene expression.

    Science.gov (United States)

    Trinh, Alice T; Ball, Bret G; Weber, Erin; Gallaher, Timothy K; Gluzman-Poltorak, Zoya; Anderson, French; Basile, Lena A

    2009-12-30

    Murine retroviral vectors have been used in several hundred gene therapy clinical trials, but have fallen out of favor for a number of reasons. One issue is that gene expression from viral or internal promoters is highly variable and essentially unregulated. Moreover, with retroviral vectors, gene expression is usually silenced over time. Mammalian genes, in contrast, are characterized by highly regulated, precise levels of expression in both a temporal and a cell-specific manner. To ascertain if recapitulation of endogenous adenosine deaminase (ADA) expression can be achieved in a vector construct we created a new series of Moloney murine leukemia virus (MuLV) based retroviral vector that carry human regulatory elements including combinations of the ADA promoter, the ADA locus control region (LCR), ADA introns and human polyadenylation sequences in a self-inactivating vector backbone. A MuLV-based retroviral vector with a self-inactivating (SIN) backbone, the phosphoglycerate kinase promoter (PGK) and the enhanced green fluorescent protein (eGFP), as a reporter gene, was generated. Subsequent vectors were constructed from this basic vector by deletion or addition of certain elements. The added elements that were assessed are the human ADA promoter, human ADA locus control region (LCR), introns 7, 8, and 11 from the human ADA gene, and human growth hormone polyadenylation signal. Retroviral vector particles were produced by transient three-plasmid transfection of 293T cells. Retroviral vectors encoding eGFP were titered by transducing 293A cells, and then the proportion of GFP-positive cells was determined using fluorescence-activated cell sorting (FACS). Non T-cell and T-cell lines were transduced at a multiplicity of infection (MOI) of 0.1 and the yield of eGFP transgene expression was evaluated by FACS analysis using mean fluorescent intensity (MFI) detection. Vectors that contained the ADA LCR were preferentially expressed in T-cell lines. Further improvements

  10. Retroviral vectors encoding ADA regulatory locus control region provide enhanced T-cell-specific transgene expression

    Science.gov (United States)

    2009-01-01

    Background Murine retroviral vectors have been used in several hundred gene therapy clinical trials, but have fallen out of favor for a number of reasons. One issue is that gene expression from viral or internal promoters is highly variable and essentially unregulated. Moreover, with retroviral vectors, gene expression is usually silenced over time. Mammalian genes, in contrast, are characterized by highly regulated, precise levels of expression in both a temporal and a cell-specific manner. To ascertain if recapitulation of endogenous adenosine deaminase (ADA) expression can be achieved in a vector construct we created a new series of Moloney murine leukemia virus (MuLV) based retroviral vector that carry human regulatory elements including combinations of the ADA promoter, the ADA locus control region (LCR), ADA introns and human polyadenylation sequences in a self-inactivating vector backbone. Methods A MuLV-based retroviral vector with a self-inactivating (SIN) backbone, the phosphoglycerate kinase promoter (PGK) and the enhanced green fluorescent protein (eGFP), as a reporter gene, was generated. Subsequent vectors were constructed from this basic vector by deletion or addition of certain elements. The added elements that were assessed are the human ADA promoter, human ADA locus control region (LCR), introns 7, 8, and 11 from the human ADA gene, and human growth hormone polyadenylation signal. Retroviral vector particles were produced by transient three-plasmid transfection of 293T cells. Retroviral vectors encoding eGFP were titered by transducing 293A cells, and then the proportion of GFP-positive cells was determined using fluorescence-activated cell sorting (FACS). Non T-cell and T-cell lines were transduced at a multiplicity of infection (MOI) of 0.1 and the yield of eGFP transgene expression was evaluated by FACS analysis using mean fluorescent intensity (MFI) detection. Results Vectors that contained the ADA LCR were preferentially expressed in T

  11. Efficacy, safety, quality control, marketing and regulatory guidelines for herbal medicines (phytotherapeutic agents

    Directory of Open Access Journals (Sweden)

    J.B. Calixto

    2000-02-01

    Full Text Available This review highlights the current advances in knowledge about the safety, efficacy, quality control, marketing and regulatory aspects of botanical medicines. Phytotherapeutic agents are standardized herbal preparations consisting of complex mixtures of one or more plants which contain as active ingredients plant parts or plant material in the crude or processed state. A marked growth in the worldwide phytotherapeutic market has occurred over the last 15 years. For the European and USA markets alone, this will reach about $7 billion and $5 billion per annum, respectively, in 1999, and has thus attracted the interest of most large pharmaceutical companies. Insufficient data exist for most plants to guarantee their quality, efficacy and safety. The idea that herbal drugs are safe and free from side effects is false. Plants contain hundreds of constituents and some of them are very toxic, such as the most cytotoxic anti-cancer plant-derived drugs, digitalis and the pyrrolizidine alkaloids, etc. However, the adverse effects of phytotherapeutic agents are less frequent compared with synthetic drugs, but well-controlled clinical trials have now confirmed that such effects really exist. Several regulatory models for herbal medicines are currently available including prescription drugs, over-the-counter substances, traditional medicines and dietary supplements. Harmonization and improvement in the processes of regulation is needed, and the general tendency is to perpetuate the German Commission E experience, which combines scientific studies and traditional knowledge (monographs. Finally, the trend in the domestication, production and biotechnological studies and genetic improvement of medicinal plants, instead of the use of plants harvested in the wild, will offer great advantages, since it will be possible to obtain uniform and high quality raw materials which are fundamental to the efficacy and safety of herbal drugs.

  12. Suppression of HIV replication by CD8+regulatory T-cells in elite controllers

    Directory of Open Access Journals (Sweden)

    Wei eLu

    2016-04-01

    Full Text Available We previously demonstrated in the Chinese macaque model that an oral vaccine made of inactivated SIV and lactobacillus plantarum induced CD8+regulatory T-cells which suppressed the activation of SIV+CD4+T-cells, prevented SIV replication and protected macaques from SIV challenges.Here ,we sought whether a similar population of CD8+T-regs would induce the suppression of HIV replication in elite controllers (ECs, a small population (3‰ of HIV-infected patients with undetectable HIV replication. For that purpose, we investigated the in vitro antiviral activity of fresh CD8+T-cells on HIV-infected CD4+T-cells taken from 10 ECs. The 10 ECs had a classical genomic profile: all of them carried the KIR3DL1 gene and nine carried at least one allele of HLA-B:Bw4-80Ile ( i.e. with an isoleucine residue at position 80. In the nine HLA-B:Bw4-80Ile positive patients, we demonstrated a strong viral suppression byKIR3DL1-expressing CD8+T-cells that required cell-to-cell contact to switch off the activation signals in infected CD4+T-cells. KIR3DL1-expressing CD8+T-cells withdrawal and KIR3DL1 neutralization by a specific anti-KIR antibody inhibited the suppression of viral replication. Our findings provide the first evidence for an instrumental role of KIR-expressing CD8+ regulatory T- cells in the natural control of HIV-1 infection.

  13. Regulatory properties of 6-phosphofructokinase and control of glycolysis in boar spermatozoa.

    Science.gov (United States)

    Kamp, G; Schmidt, H; Stypa, H; Feiden, S; Mahling, C; Wegener, G

    2007-01-01

    Glycolysis is crucial for sperm functions (motility and fertilization), but how this pathway is regulated in spermatozoa is not clear. This prompted to study the location and the regulatory properties of 6-phosphofructokinase (PFK, EC 2.7.1.11), the most important element for control of glycolytic flux. Unlike some other glycolytic enzymes, PFK showed no tight binding to sperm structures. It could readily be extracted from ejaculated boar spermatozoa by sonication and was then chromatographically purified. At physiological pH, the enzyme was allosterically inhibited by near-physiological concentrations of its co-substrate ATP, which induced co-operativity, i.e. reduced the affinity for the substrate fructose 6-phosphate. Inhibition by ATP was reinforced by citrate and H+. Above pH 8, PFK lost all its regulatory properties and showed maximum activity. However, in the physiological pH range, PFK activity was very sensitive to small changes in effectors. At near-physiological substrate concentrations, PFK activity requires activators (de-inhibitors) of which the combination of AMP and fructose 2,6-bisphosphate (F2,6P2) was most efficient as a result of synergistic effects. The kinetics of PFK suggest AMP, F2,6P2, H+, and citrate as allosteric effectors controlling PFK activity in boar spermatozoa. Using immunogold labeling, PFK was localized in the mid-piece and principal piece of the flagellum as well as in the acrosomal area at the top of the head and in the cytoplasmic droplets released from the mid-piece after ejaculation.

  14. Positive lists of cosmetic ingredients: Analytical methodology for regulatory and safety controls - A review.

    Science.gov (United States)

    Lores, Marta; Llompart, Maria; Alvarez-Rivera, Gerardo; Guerra, Eugenia; Vila, Marlene; Celeiro, Maria; Lamas, J Pablo; Garcia-Jares, Carmen

    2016-04-07

    Cosmetic products placed on the market and their ingredients, must be safe under reasonable conditions of use, in accordance to the current legislation. Therefore, regulated and allowed chemical substances must meet the regulatory criteria to be used as ingredients in cosmetics and personal care products, and adequate analytical methodology is needed to evaluate the degree of compliance. This article reviews the most recent methods (2005-2015) used for the extraction and the analytical determination of the ingredients included in the positive lists of the European Regulation of Cosmetic Products (EC 1223/2009): comprising colorants, preservatives and UV filters. It summarizes the analytical properties of the most relevant analytical methods along with the possibilities of fulfilment of the current regulatory issues. The cosmetic legislation is frequently being updated; consequently, the analytical methodology must be constantly revised and improved to meet safety requirements. The article highlights the most important advances in analytical methodology for cosmetics control, both in relation to the sample pretreatment and extraction and the different instrumental approaches developed to solve this challenge. Cosmetics are complex samples, and most of them require a sample pretreatment before analysis. In the last times, the research conducted covering this aspect, tended to the use of green extraction and microextraction techniques. Analytical methods were generally based on liquid chromatography with UV detection, and gas and liquid chromatographic techniques hyphenated with single or tandem mass spectrometry; but some interesting proposals based on electrophoresis have also been reported, together with some electroanalytical approaches. Regarding the number of ingredients considered for analytical control, single analyte methods have been proposed, although the most useful ones in the real life cosmetic analysis are the multianalyte approaches. Copyright © 2016

  15. Long-term tolerability of inhaled human insulin (Exubera) in patients with poorly controlled type 2 diabetes

    DEFF Research Database (Denmark)

    Barnett, A H; Lange, P; Dreyer, M

    2007-01-01

    OBJECTIVE: Inhaled human insulin (Exubera; EXU) has shown encouraging tolerability in short-term trials. We evaluated the safety profile of EXU after long-term exposure. DESIGN: In two, open-label, 2-year studies patients poorly controlled on a sulphonylurea were randomised to adjunctive EXU...... or metformin (study 1) and patients poorly controlled on metformin were randomised to adjunctive EXU or the sulphonylurea, glibenclamide (study 2). PATIENTS: The studies included 446 (study 1) and 476 (study 2) patients with type 2 diabetes, no clinically significant respiratory disease and glycosylated....... There was no discernable effect of long-term EXU therapy on pulmonary gas exchange. Insulin antibody binding reached a plateau at 6 months and did not correlate with HbA(1c) or lung function changes. Glycaemic control was maintained over 2 years. CONCLUSIONS: Exubera was well tolerated during long-term use. Pulmonary...

  16. Regulatory control for safe usage of ionizing radiation sources in Bangladesh

    International Nuclear Information System (INIS)

    Mollah, A.S.

    2008-01-01

    Full text: In Bangladesh, there is a widespread and continuos growth in the use of the ionizing radiation sources both radioactive materials and radiation generating equipment in the field of industry, medicine, agriculture, research, teaching etc. In industry, they are employed in production as well as quality control such as non-destructive testing (radiography), nucleonic gauging, radiotracer techniques and in radiation processing. Medical applications of ionizing radiation include X-ray radiography, X-ray fluoroscopy, CT scan, mammography, nuclear medicine, beam therapy and brachytherapy. Besides radioisotopes are also used for research applications, viz., scattering experiments, tracer studies, etc. In agriculture, the uptake of nutrients by soil, and parts of plants are studied using suitable radionuclides. In all the above applications radioisotopes in two forms namely sealed sources and open sources in different chemical forms are employed with source strengths varying from micro curies to mega curies. The benefits to man from the use of ionizing radiation and sources of radiation are accompanied by risks which may result from exposure of man to ionizing radiation. In order to have an effective control on the use of radiation sources and to ensure radiological safety of the user as well as the public, Government of Bangladesh has promulgated Nuclear Safety and Radiation Control (NSRC) rules 1997 under the NSRC Act 1993. The Bangladesh Atomic Energy commission (BAEC) is the competent authority for formulating rules and regulations for ensuring radiological safety. BAEC is legally responsible for developing and strengthening the necessary radiation protection infrastructure in the country through the effective enforcement and implementation of regulatory requirements, criteria, obligations, guiding, codes etc. in order to save man and the related environment from the deleterious effects of ionizing radiation. In Bangladesh, only those persons who have been

  17. Regulatory Research of the PWR Severe Accident. Information Needs and Instrumentation for Hydrogen Control and Management

    International Nuclear Information System (INIS)

    Park, Gun Chul; Suh, Kune Y.; Lee, Jin Yong; Lee, Seung Dong

    2001-03-01

    The current research is concerned with generation of basic engineering data needed in the process of developing hydrogen control guidelines as part of accident management strategies for domestic nuclear power plants and formulating pertinent regulatory requirements. Major focus is placed on identification of information needs and instrumentation methods for hydrogen control and management in the primary system and in the containment, development of decision-making trees for hydrogen management and their quantification, the instrument availability under severe accident conditions, critical review of relevant hydrogen generation model and phenomena In relation to hydrogen behavior, we analyzed the severe accident related hydrogen generation in the UCN 3·4 PWR with modified hydrogen generation model. On the basis of the hydrogen mixing experiment and related GASFLOW calculation, the necessity of 3-dimensional analysis of the hydrogen mixing was investigated. We examined the hydrogen control models related to the PAR(Passive Autocatalytic Recombiner) and performed MAAP4 calculation in relation to the decision tree to estimate the capability and the role of the PAR during a severe accident

  18. Regulatory control and safety of radiation and radioactive sources in Bangladesh

    International Nuclear Information System (INIS)

    Mollah, A.S.

    2001-01-01

    The application of ionizing radiation and radioactive sources in different fields such as, medicine, industry, agriculture, research and teaching is constantly increasing in Bangladesh. Any system enacted to control exposure to ionizing radiation has as primary objective the protection of health of people against the deleterious effects of radiation. Establishing the appropriate level of radiological protection and safety of radiation sources used in practice or intervention attains this objective. The regulatory program governing the safe use of radioactive and radiation sources in Bangladesh is based on the legislation enacted as Nuclear Safety and Radiation Control (NSRC) Act-93 and NSRC Rules-97 and its implementation by the competent authority. The radiation control infrastructures and procedure are described as well as their functioning for the implementation of relevant activities such as licensing, regular inspection, personal dose monitoring, emergency preparedness, etc. The issue of security of radiation source is dealt in close relation with the preparation and use of the inventory of all radiation sources in the country

  19. Control of Stochastic Master Equation Models of Genetic Regulatory Networks by Approximating Their Average Behavior

    Science.gov (United States)

    Umut Caglar, Mehmet; Pal, Ranadip

    2010-10-01

    The central dogma of molecular biology states that ``information cannot be transferred back from protein to either protein or nucleic acid.'' However, this assumption is not exactly correct in most of the cases. There are a lot of feedback loops and interactions between different levels of systems. These types of interactions are hard to analyze due to the lack of data in the cellular level and probabilistic nature of interactions. Probabilistic models like Stochastic Master Equation (SME) or deterministic models like differential equations (DE) can be used to analyze these types of interactions. SME models based on chemical master equation (CME) can provide detailed representation of genetic regulatory system, but their use is restricted by the large data requirements and computational costs of calculations. The differential equations models on the other hand, have low calculation costs and much more adequate to generate control procedures on the system; but they are not adequate to investigate the probabilistic nature of interactions. In this work the success of the mapping between SME and DE is analyzed, and the success of a control policy generated by DE model with respect to SME model is examined. Index Terms--- Stochastic Master Equation models, Differential Equation Models, Control Policy Design, Systems biology

  20. Regulatory Research of the PWR Severe Accident. Information Needs and Instrumentation for Hydrogen Control and Management

    Energy Technology Data Exchange (ETDEWEB)

    Park, Gun Chul; Suh, Kune Y.; Lee, Jin Yong; Lee, Seung Dong [Seoul Nat' l Univ., Seoul (Korea, Republic of)

    2001-03-15

    The current research is concerned with generation of basic engineering data needed in the process of developing hydrogen control guidelines as part of accident management strategies for domestic nuclear power plants and formulating pertinent regulatory requirements. Major focus is placed on identification of information needs and instrumentation methods for hydrogen control and management in the primary system and in the containment, development of decision-making trees for hydrogen management and their quantification, the instrument availability under severe accident conditions, critical review of relevant hydrogen generation model and phenomena In relation to hydrogen behavior, we analyzed the severe accident related hydrogen generation in the UCN 3{center_dot}4 PWR with modified hydrogen generation model. On the basis of the hydrogen mixing experiment and related GASFLOW calculation, the necessity of 3-dimensional analysis of the hydrogen mixing was investigated. We examined the hydrogen control models related to the PAR(Passive Autocatalytic Recombiner) and performed MAAP4 calculation in relation to the decision tree to estimate the capability and the role of the PAR during a severe accident.

  1. Weed control changes and genetically modified herbicide tolerant crops in the USA 1996-2012.

    Science.gov (United States)

    Brookes, Graham

    2014-01-01

    Crops that have been genetically modified (GM) to be tolerant to herbicides have been widely grown in the USA since 1996. The rapid and widespread adoption of this technology reflects the important economic and environmental benefits that farmers have derived from its use (equal to $21.7 billion additional farm income and a 225 million kg reduction in herbicide active ingredient use 1996-2012). During this time, weed control practices in these crops relative to the 'conventional alternative' have evolved to reflect experience of using the technology, the challenges that have arisen and the increasing focus in recent years on developing sustainable production systems. This paper examines the evidence on the changing nature of herbicides used with these crops and in particular how farmers addressed the challenge of weed resistance. The evidence shows that use of the technology has resulted in a net reduction in both the amount of herbicide used and the associated environmental impact, as measured by the EIQ indicator when compared to what can reasonably be expected if the area planted to GM HT crops reverted to conventional production methods. It also facilitated many farmers being able to derive the economic and environmental benefits associated with switching from a plough-based to a no tillage or conservation tillage production system. In terms of herbicide use, the technology has also contributed to a change the profile of herbicides used. A broad range of, mostly selective herbicides has been replaced by one or 2 broad-spectrum herbicides (mostly glyphosate) used in conjunction with one or 2 other (complementary) herbicides. Since the mid-2000s, the average amount of herbicide applied and the associated environmental load, as measured by the EIQ indicator, have increased on both GM HT and conventional crops. A primary reason for these changes has been increasing incidence of weed species developing populations resistant to herbicides and increased awareness of

  2. Overcoming beta-agonist tolerance: high dose salbutamol and ipratropium bromide. Two randomised controlled trials

    Directory of Open Access Journals (Sweden)

    Haney Sarah

    2007-03-01

    Full Text Available Abstract Background Asthmatics treated with long-acting beta-agonists have a reduced bronchodilator response to moderate doses of inhaled short acting beta-agonists during acute bronchoconstriction. It is not known if the response to higher doses of nebulised beta-agonists or other bronchodilators is impaired. We assessed the effect of long-acting beta-agonist treatment on the response to 5 mg nebulised salbutamol and to ipratropium bromide. Methods Two double-blind, placebo-controlled, crossover studies of inhaled formoterol 12 μg twice daily in patients with asthma. High-dose salbutamol: 36 hours after the last dose of 1 week of formoterol or placebo treatment, 11 subjects inhaled methacholine to produce a 20% fall in FEV1. Salbutamol 5 mg was then administered via nebuliser and the FEV1 was monitored for 20 minutes. Ipratropium: 36 hours after the last dose of 1 week of formoterol or placebo treatment, 11 subjects inhaled 4.5% saline to produce a 20% fall in FEV1. Salbutamol 200 μg or ipratropium bromide 40 μg was then inhaled and the FEV1 was monitored for 30 minutes. Four study arms compared the response to each bronchodilator after formoterol and placebo. Analyses compared the area under the bronchodilator response curves, adjusting for changes in pre-challenge FEV1, dose of provocational agent and FEV1 fall during the challenge procedure. Results The response to nebulised salbutamol was 15% lower after formoterol therapy compared to placebo (95% confidence 5 to 25%, p = 0.008. The response to ipratropium was unchanged. Conclusion Long-acting beta-agonist treatment induces tolerance to the bronchodilator effect of beta-agonists, which is not overcome by higher dose nebulised salbutamol. However, the bronchodilator response to ipratropium bromide is unaffected.

  3. A gene regulatory network controlling hhex transcription in the anterior endoderm of the organizer

    Science.gov (United States)

    Rankin, Scott A.; Kormish, Jay; Kofron, Matt; Jegga, Anil; Zorn, Aaron M.

    2011-01-01

    The homeobox gene hhex is one of the earliest markers of the anterior endoderm, which gives rise to foregut organs such as the liver, ventral pancreas, thyroid, and lungs. The regulatory networks controlling hhex transcription are poorly understood. In an extensive cis-regulatory analysis of the Xenopus hhex promoter we determined how the Nodal, Wnt, and BMP pathways and their downstream transcription factors regulate hhex expression in the gastrula organizer. We show that Nodal signaling, present throughout the endoderm, directly activates hhex transcription via FoxH1/Smad2 binding sites in the proximal −0.44 Kb promoter. This positive action of Nodal is suppressed in the ventral-posterior endoderm by Vent 1 and Vent2, homeodomain repressors that are induced by BMP signaling. Maternal Wnt/β-catenin on the dorsal side of the embryo cooperates with Nodal and indirectly activate hhex expression via the homeodomain activators Siamois and Twin. Siamois/Twin stimulate hhex transcription through two mechanisms: 1) They induce the expression of Otx2 and Lim1 and together Siamois, Twin, Otx2 and Lim1 appear to promote hhex transcription through homeobox sites in a Wnt-responsive element located between −0.65 to −0.55 Kb of the hhex promoter. 2) Siamois/Twin also induce the expression of the BMP-antagonists Chordin and Noggin, which are required to exclude Vents from the organizer allowing hhex transcription. This work reveals a complex network regulating anterior endoderm transcription in the early embryo. PMID:21215263

  4. Regulatory control and challenges in Medical facilities using ionising radiation sources

    International Nuclear Information System (INIS)

    Agarwal, S.P.

    2008-01-01

    Medical facilities utilising ionising radiation sources for diagnostic and treatment of cancer are regulated under the provisions of Atomic Energy (Radiation Protection) Rules, 2004 promulgated under the Atomic Energy Act 1962. The Competent Authority for the enforcement of the rules is Chairman, Atomic Energy Regulatory Board (AERB). Practice specific codes are issued by AERB for medical facilities such as Radiotherapy, Nuclear Medicine and Radiology. Regulatory process for control of medical facilities covers the entire life cycle of the radiation sources in three stages viz pre-Iicensing, during useful life and decommissioning and disposal. Pre-Iicensing requirements include use of type approved sources and equipment, approval of design layout of the facility and installation, exclusive (safe and secure) source storage facility when the equipment is not in use, radiation (area/individual) monitoring devices, qualified, trained and certified manpower, emergency response plans and commitment from the licensee for the safe disposal of disused/decayed sources. Compliance to these requirements makes the applicant eligible to obtain license from AERB for the operation of the medical facility. During the use of radiation sources, specific prior approval of the Competent Authority is required in respect of every source replacement, sale, transfer, transport, import and export. Further, all licensees are required to send the periodic safety Status reports to AERB as well as reporting of any off normal events. AERB conducts inspection of the facilities to ensure compliance with the safety requirements during operation of the facility. Violation of safety norms by licensee attracts enforcement action which includes suspension, modification or withdrawal of licensee for operation of the facility. Upon completion of the useful life of the source, the licensee decommissions the facility and returns the source to the original supplier. For returning the source, prior

  5. Pilot exemption of the controlled area from regulatory control at NPP A1 -lessons learned

    International Nuclear Information System (INIS)

    Slaninka, A.; Listjak, M.; Slavik, O.; Rau, L.

    2014-01-01

    The contribution includes the lessons learned within frame of the radiological characterisation of surface ground layer in the NPP A1 site of area approximately 60 m2 (9 x 7 m) that was a part of Controlled area. Aim of the characterisation was a demonstration that the area fulfils the requirements to exemption from Controlled area for purpose of decommissioning activities carry out within frame of II. stage of NPP A1 decommissioning project.The requirements on free release of materials into the environment were applied (e.g. 300 Bq/kg for single 137 Cs). Radiological characterisation was performed by two independent methods; in situ scintillation gamma spectrometry and systematic sampling in regular grid followed by gamma spectrometry analyses in accredited laboratory of VUJE, Inc. (S-219). This improved the quality of monitoring and at the same time it enabled the inter-comparison of results obtained by both mentioned independent methods.Characterised ground area was partitioned to smaller sub-areas of 4 m2. At ground layer of 20 cm it means approximately 1000 kg of ground (in compliance with requirements on reference area at even activity distribution according to government regulation No 345/2006) The results of measurements showed that under appropriate conditions (sufficiently low radiation background, on interfering external sources) also the designed in situ method is effective and reliable tool for contaminated ground layer identification. In addition the in situ method is more effective in terms of time and cost consumption on unit of monitored area. (authors)

  6. Fault tolerant control of a three-phase three-wire shunt active filter system based on reliability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Poure, P. [Laboratoire d' Instrumentation Electronique de Nancy LIEN, EA 3440, Nancy-Universite, Faculte des Sciences et Techniques, BP 239, 54506 Vandoeuvre Cedex (France); Weber, P.; Theilliol, D. [Centre de Recherche en Automatique de Nancy UMR 7039, Nancy-Universite, CNRS, Faculte des Sciences et Techniques, BP 239, 54506 Vandoeuvre Cedex (France); Saadate, S. [Groupe de Recherches en Electrotechnique et Electronique de Nancy UMR 7037, Nancy-Universite, CNRS, Faculte des Sciences et Techniques, BP 239, 54506 Vandoeuvre Cedex (France)

    2009-02-15

    This paper deals with fault tolerant shunt three-phase three-wire active filter topologies for which reliability is very important in industry applications. The determination of the optimal reconfiguration structure among various ones with or without redundant components is discussed based on reliability criteria. First, the reconfiguration of the inverter is detailed and a fast fault diagnosis method for power semi-conductor or driver fault detection and compensation is presented. This method avoids false fault detection due to power semi-conductors switching. The control architecture and algorithm are studied and a fault tolerant control strategy is considered. Simulation results in open and short circuit cases validate the theoretical study. Finally, the reliability of the studied three-phase three-wire filter shunt active topologies is analyzed to determine the optimal one. (author)

  7. Active fault tolerance control of a wind turbine system using an unknown input observer with an actuator fault

    Directory of Open Access Journals (Sweden)

    Li Shanzhi

    2018-03-01

    Full Text Available This paper proposes a fault tolerant control scheme based on an unknown input observer for a wind turbine system subject to an actuator fault and disturbance. Firstly, an unknown input observer for state estimation and fault detection using a linear parameter varying model is developed. By solving linear matrix inequalities (LMIs and linear matrix equalities (LMEs, the gains of the unknown input observer are obtained. The convergence of the unknown input observer is also analysed with Lyapunov theory. Secondly, using fault estimation, an active fault tolerant controller is applied to a wind turbine system. Finally, a simulation of a wind turbine benchmark with an actuator fault is tested for the proposed method. The simulation results indicate that the proposed FTC scheme is efficient.

  8. Independent regulatory control and monitoring of the environment at the uranium legacy sites under reclamation

    International Nuclear Information System (INIS)

    Shandala, N.K.; Titov, A.V.; Kiselev, S.M.; Isaev, D.V.; Aladova, R.A.

    2012-01-01

    Full text: Radiation safety at areas affected by the natural uranium mining and milling facilities is very important for the environment protection and human health. For this purpose the close operator-regulator contact is required during remedial operations. One of the key mechanisms of the operating regulatory supervision of radiation safety at uranium legacy sites is organization of independent radiation control and monitoring in the course of reclamation and after its completion. The main stages of this strategy include: detailed radiation survey at the area and in the vicinity of the former uranium mining sites; threat assessment in order to identify the regulatory priorities; environmental radiation control and monitoring. Tailings and shallow disposal sites of the uranium mining wastes are the most critical areas in terms of potential hazard for the environment. Tailings are the source of contamination of the near-land air due to the radionuclide dust resuspension from the tailing surface; surface and ground water due to washing out from by precipitation and surface streams of toxic and radioactive elements. Frequently, contamination of surface and ground waters results in some problems, especially when using the leaching fluids for the solution mining and draining hydraulic fluids. Radiation risk for the residents of areas near not operating uranium mining and milling facilities depends on the following factors: radon exhalation from the surface of dumps and tailing; radioactive dust transfer; using radioactive material in building; contamination of surface water streams and aquifers used for drinking water supply; contamination of open ponds used for fish breeding and catching; contamination of foodstuffs grown in the nuclear legacy areas. Radiation monitoring is necessary for the up-to-date response to changing radiation situation during reclamation and arrangement of adequate countermeasures. We mean here comprehensive dynamic surveillance including long

  9. Inhibition of Non-flux-Controlling Enzymes Deters Cancer Glycolysis by Accumulation of Regulatory Metabolites of Controlling Steps.

    Science.gov (United States)

    Marín-Hernández, Álvaro; Rodríguez-Zavala, José S; Del Mazo-Monsalvo, Isis; Rodríguez-Enríquez, Sara; Moreno-Sánchez, Rafael; Saavedra, Emma

    2016-01-01

    Glycolysis provides precursors for the synthesis of macromolecules and may contribute to the ATP supply required for the constant and accelerated cellular duplication in cancer cells. In consequence, inhibition of glycolysis has been reiteratively considered as an anti-cancer therapeutic option. In previous studies, kinetic modeling of glycolysis in cancer cells allowed the identification of the main steps that control the glycolytic flux: glucose transporter, hexokinase (HK), hexose phosphate isomerase (HPI), and glycogen degradation in human cervix HeLa cancer cells and rat AS-30D ascites hepatocarcinoma. It was also previously experimentally determined that simultaneous inhibition of the non-controlling enzymes lactate dehydrogenase (LDH), pyruvate kinase (PYK), and enolase (ENO) brings about significant decrease in the glycolytic flux of cancer cells and accumulation of intermediate metabolites, mainly fructose-1,6-bisphosphate (Fru1,6BP), and dihydroxyacetone phosphate (DHAP), which are inhibitors of HK and HPI, respectively. Here it was found by kinetic modeling that inhibition of cancer glycolysis can be attained by blocking downstream non flux-controlling steps as long as Fru1,6BP and DHAP, regulatory metabolites of flux-controlling enzymes, are accumulated. Furthermore, experimental results and further modeling showed that oxamate and iodoacetate inhibitions of PYK, ENO, and glyceraldehyde3-phosphate dehydrogenase (GAPDH), but not of LDH and phosphoglycerate kinase, induced accumulation of Fru1,6BP and DHAP in AS-30D hepatoma cells. Indeed, PYK, ENO, and GAPDH exerted the highest control on the Fru1,6BP and DHAP concentrations. The high levels of these metabolites inhibited HK and HPI and led to glycolytic flux inhibition, ATP diminution, and accumulation of toxic methylglyoxal. Hence, the anticancer effects of downstream glycolytic inhibitors are very likely mediated by this mechanism. In parallel, it was also found that uncompetitive inhibition of the

  10. Confinement of activating receptors at the plasma membrane controls natural killer cell tolerance.

    Science.gov (United States)

    Guia, Sophie; Jaeger, Baptiste N; Piatek, Stefan; Mailfert, Sébastien; Trombik, Tomasz; Fenis, Aurore; Chevrier, Nicolas; Walzer, Thierry; Kerdiles, Yann M; Marguet, Didier; Vivier, Eric; Ugolini, Sophie

    2011-04-05

    Natural killer (NK) cell tolerance to self is partly ensured by major histocompatibility complex (MHC) class I-specific inhibitory receptors on NK cells, which dampen their reactivity when engaged. However, NK cells that do not detect self MHC class I are not autoreactive. We used dynamic fluorescence correlation spectroscopy to show that MHC class I-independent NK cell tolerance in mice was associated with the presence of hyporesponsive NK cells in which both activating and inhibitory receptors were confined in an actin meshwork at the plasma membrane. In contrast, the recognition of self MHC class I by inhibitory receptors "educated" NK cells to become fully reactive, and activating NK cell receptors became dynamically compartmentalized in membrane nanodomains. We propose that the confinement of activating receptors at the plasma membrane is pivotal to ensuring the self-tolerance of NK cells.

  11. Kaempferol Promotes Transplant Tolerance by Sustaining CD4+FoxP3+ Regulatory T Cells in the Presence of Calcineurin Inhibitor.

    Science.gov (United States)

    Zeng, Y Q; Liu, X S; Wu, S; Zou, C; Xie, Q; Xu, S M; Jin, X W; Li, W; Zhou, A; Dai, Z

    2015-07-01

    Calcineurin inhibitor cyclosporine is widely used as an immunosuppressant in clinic. However, mounting evidence has shown that cyclosporine hinders tolerance induction by dampening Tregs. Therefore, it is of paramount importance to overcome this pitfall. Kaempferol was reported to inhibit DC function. Here, we found that kaempferol delayed islet allograft rejection. Combination of kaempferol and low-dose, but not high-dose, of cyclosporine induced allograft tolerance in majority of recipient mice. Although kaempferol plus either dose of cyclosporine largely abrogated proliferation of graft-infiltrating T cells and their CTL activity, both proliferation and CTL activity in mice treated with kaempferol plus low-dose, but not high-dose, cyclosporine reemerged rapidly upon treatment withdrawal. Kaempferol increased CD4+FoxP3+ Tregs both in transplanted mice and in vitro, likely by suppressing DC maturation and their IL-6 expression. Reduction in Tregs by low dose of cyclosporine was reversed by kaempferol. Kaempferol-induced Tregs exhibited both allospecific and non-allospecific suppression. Administering IL-6 abrogated allograft tolerance induced by kaempferol and cyclosporine via diminishing CD4+FoxP3+ Tregs. Thus, for the first time, we demonstrated that kaempferol promotes transplant tolerance in the presence of low dose of cyclosporine, which allows for sufficient Treg generation while minimizing side effects, resulting in much-needed synergy between kaempferol and cyclosporine. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  12. Evaluation of Freezing Tolerance of Hexaploid Triticale Genotypes under Controlled Conditions

    Directory of Open Access Journals (Sweden)

    Ahmad, NEZAMI

    2010-06-01

    Full Text Available In order to evaluate freezing tolerance of different triticale (X Triticosecale Wittmack genotypes, an experiment was carried out under controlled conditions in 2007 and 2008 at college of agriculture, Ferdowsi University of Mashhad. In this study seeven triticale genotypes (�Juanilo-92�, �ET-82-15�, �ET-82-8�, �ET-83-20�, �ET-83-19�, �ET-83-18� and �ET-79-17�, across six temperatures (0�C, -4�C, -8�C, -12�C, -16�C and -20�C were evaluated within a factorial-completely randomized design with three replications. Plants were kept until 2 leaf stage in chamber with temperature of 20/15�C (day/night and 12.5 h photoperiod. At the end of this stage, plants were under acclimation for three weeks. After exposing to acclimation freezing the cell membrane integrity was measured through electrolyte leakage (EL and the lethal temperature (LT50 of samples was measured. After the exposure to freezing temperatures the samples were transferred to the greenhouse. Survival percentage, plant height, leaf area and number, chlorophyll content, and plant dry weight were determined after 3 weeks. Results showed that the effect of different freezing temperature and genotypes were significant on all plant characteristics. As temperature decreased, %EL of all genotypes was increased. Minimum and Maximum EL % in leaf and crown were observed at 0�C (21% and -20�C (88.5%. �ET-79-17� and �Juanilo-92� genotypes showed the highest EL% (55.5% and 44.8% and �ET-83-20� the lowest EL% (47.3% and 41.2% in leaf and crown. Dry weight and leaf area decreased by 48% and 42% respectively compared to non frozen control plants. �ET-79-17� and �ET-82-15� genotypes showed the highest dry weight (83.8 mg and highest leaf area (14.3 cm2 respectively and �ET-83-20� cultivar showed the lowest dry weight and leaf area (58.2 mg and 8.7 cm2.

  13. Evaluation of Freezing Tolerance of Hexaploid Triticale Genotypes under Controlled Conditions

    Directory of Open Access Journals (Sweden)

    Ahmad, NEZAMI

    2010-06-01

    Full Text Available In order to evaluate freezing tolerance of different triticale (X Triticosecale Wittmack genotypes, an experiment was carried out under controlled conditions in 2007 and 2008 at college of agriculture, Ferdowsi University of Mashhad. In this study seeven triticale genotypes (Juanilo-92, ET-82-15, ET-82-8, ET-83-20, ET-83-19, ET-83-18 and ET-79-17, across six temperatures (0C, -4C, -8C, -12C, -16C and -20C were evaluated within a factorial-completely randomized design with three replications. Plants were kept until 2 leaf stage in chamber with temperature of 20/15C (day/night and 12.5 h photoperiod. At the end of this stage, plants were under acclimation for three weeks. After exposing to acclimation freezing the cell membrane integrity was measured through electrolyte leakage (EL and the lethal temperature (LT50 of samples was measured. After the exposure to freezing temperatures the samples were transferred to the greenhouse. Survival percentage, plant height, leaf area and number, chlorophyll content, and plant dry weight were determined after 3 weeks. Results showed that the effect of different freezing temperature and genotypes were significant on all plant characteristics. As temperature decreased, %EL of all genotypes was increased. Minimum and Maximum EL % in leaf and crown were observed at 0C (21% and -20C (88.5%. ET-79-17 and Juanilo-92 genotypes showed the highest EL% (55.5% and 44.8% and ET-83-20 the lowest EL% (47.3% and 41.2% in leaf and crown. Dry weight and leaf area decreased by 48% and 42% respectively compared to non frozen control plants. ET-79-17 and ET-82-15 genotypes showed the highest dry weight (83.8 mg and highest leaf area (14.3 cm2 respectively and ET-83-20 cultivar showed the lowest dry weight and leaf area (58.2 mg and 8.7 cm2.

  14. The Cellular and Molecular Mechanisms of Immuno-suppression by Human Type 1 Regulatory T cells

    Directory of Open Access Journals (Sweden)

    Silvia eGregori

    2012-02-01

    Full Text Available The immuno-regulatory mechanisms of IL-10-producing type 1 regulatory T (Tr1 cells have been widely studied over the years. However, several recent discoveries have shed new light on the cellular and molecular mechanisms that human Tr1 cells use to control immune responses and induce tolerance. In this review we outline the well-known and newly discovered regulatory properties of human Tr1 cells and provide an in-depth comparison of the known suppressor mechanisms of Tr1 cells with FOXP3+ Treg. We also highlight the role that Tr1 cells play in promoting and maintaining tolerance in autoimmunity, allergy, and transplantation.

  15. Casein kinase 1 regulates sterol regulatory element-binding protein (SREBP) to control sterol homeostasis.

    Science.gov (United States)

    Brookheart, Rita T; Lee, Chih-Yung S; Espenshade, Peter J

    2014-01-31

    Sterol homeostasis is tightly controlled by the sterol regulatory element-binding protein (SREBP) transcription factor that is highly conserved from fungi to mammals. In fission yeast, SREBP functions in an oxygen-sensing pathway to promote adaptation to decreased oxygen supply that limits oxygen-dependent sterol synthesis. Low oxygen stimulates proteolytic cleavage of the SREBP homolog Sre1, generating the active transcription factor Sre1N that drives expression of sterol biosynthetic enzymes. In addition, low oxygen increases the stability and DNA binding activity of Sre1N. To identify additional signals controlling Sre1 activity, we conducted a genetic overexpression screen. Here, we describe our isolation and characterization of the casein kinase 1 family member Hhp2 as a novel regulator of Sre1N. Deletion of Hhp2 increases Sre1N protein stability and ergosterol levels in the presence of oxygen. Hhp2-dependent Sre1N degradation by the proteasome requires Hhp2 kinase activity, and Hhp2 binds and phosphorylates Sre1N at specific residues. Our results describe a role for casein kinase 1 as a direct regulator of sterol homeostasis. Given the role of mammalian Hhp2 homologs, casein kinase 1δ and 1ε, in regulation of the circadian clock, these findings may provide a mechanism for coordinating circadian rhythm and lipid metabolism.

  16. Multiple independent regulatory pathways control UBI4 expression after heat shock in Saccharomyces cerevisiae.

    Science.gov (United States)

    Simon, J R; Treger, J M; McEntee, K

    1999-02-01

    Transcription of the polyubiquitin gene UBI4 of Saccharomyces cerevisiae is strongly induced by a variety of environmental stresses, such as heat shock, nutrient depletion and exposure to DNA-damaging agents. This transcriptional response of UBI4 is likely to be the primary mechanism for increasing the pool of ubiquitin for degradation of stress-damaged proteins. Deletion and promoter fusion studies of the 5' regulatory sequences indicated that two different elements, heat shock elements (HSEs) and stress response element (STREs), contributed independently to heat shock regulation of the UBI4 gene. In the absence of HSEs, STRE sequences localized to the intervals -264 to -238 and -215 to -183 were needed for stress control of transcription after heat shock. Site-directed mutagenesis of the STRE (AG4) at -252 to -248 abolished heat shock induction of UBI4 transcription. Northern analysis demonstrated that cells containing either a temperature-sensitive HSF or non-functional Msn2p/Msn4p transcription factors induced high levels of UBI4 transcripts after heat shock. In cells deficient in both heat stress pathways, heat-induced UBI4 transcript levels were considerably lower but not abolished, suggesting a role for another factor(s) in stress control of its expression.

  17. Fault diagnosis and fault-tolerant finite control set-model predictive control of a multiphase voltage-source inverter supplying BLDC motor.

    Science.gov (United States)

    Salehifar, Mehdi; Moreno-Equilaz, Manuel

    2016-01-01

    Due to its fault tolerance, a multiphase brushless direct current (BLDC) motor can meet high reliability demand for application in electric vehicles. The voltage-source inverter (VSI) supplying the motor is subjected to open circuit faults. Therefore, it is necessary to design a fault-tolerant (FT) control algorithm with an embedded fault diagnosis (FD) block. In this paper, finite control set-model predictive control (FCS-MPC) is developed to implement the fault-tolerant control algorithm of a five-phase BLDC motor. The developed control method is fast, simple, and flexible. A FD method based on available information from the control block is proposed; this method is simple, robust to common transients in motor and able to localize multiple open circuit faults. The proposed FD and FT control algorithm are embedded in a five-phase BLDC motor drive. In order to validate the theory presented, simulation and experimental results are conducted on a five-phase two-level VSI supplying a five-phase BLDC motor. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Effects of methadone hydrochloride on the growth of organotypic cerebellar cultures prepared from methadone-tolerant and control rats.

    Science.gov (United States)

    Willson, N J; Schneider, J F; Roizin, L; Fleiss, J F; Rivers, W; Demartini, J E

    1976-11-01

    Male and female Sprague-Dawley rats were given dl-methadone (5 mg/kg) for at least 3 months and then mated. The drug was continued throughout pregnancy and after delivery. The newly born pups were divided into two groups. One group was tested for in vivo methadone tolerance, while the animals in the othergroup were used to prepare organotypic cerebellar cultures. Various amounts of dl-methadone were added to the media of half of these cerebellum cultures. The effect of the drug in the medium was assessed by measuring explant outgrowth. Similar experiments were carried out with control animals. Statistical analysis of the data obtained in the in vivo portion of the experiment indicates that the pups of methadone-treated mothers tolerate methadone better than those of untreated mothers. The culture experiments revealed that the addition of methadone to the medium reduced explant outgrowth size and this was a dose-related effect. Also, there was significantly less outgrowth from explants prepared using pups of methadone-treated mothers as compared to the controls. There was no significant difference in the effect of methadone on the growth of cultures prepared from the methadone-tolerant and control animals.

  19. Infectious Tolerance

    Science.gov (United States)

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, freshly isolated CD4+ T helper (Th) cells. This infectious suppressive activity, transferred from CD25+ Treg cells via cell contact, is cell contact–independent and partially mediated by soluble transforming growth factor (TGF)-β. The induction of suppressive properties in conventional CD4+ Th cells represents a mechanism underlying the phenomenon of infectious tolerance. This explains previously published conflicting data on the role of TGF-β in CD25+ Treg cell–induced immunosuppression. PMID:12119350

  20. Robust Fault-Tolerant Control for Satellite Attitude Stabilization Based on Active Disturbance Rejection Approach with Artificial Bee Colony Algorithm

    Directory of Open Access Journals (Sweden)

    Fei Song

    2014-01-01

    Full Text Available This paper proposed a robust fault-tolerant control algorithm for satellite stabilization based on active disturbance rejection approach with artificial bee colony algorithm. The actuating mechanism of attitude control system consists of three working reaction flywheels and one spare reaction flywheel. The speed measurement of reaction flywheel is adopted for fault detection. If any reaction flywheel fault is detected, the corresponding fault flywheel is isolated and the spare reaction flywheel is activated to counteract the fault effect and ensure that the satellite is working safely and reliably. The active disturbance rejection approach is employed to design the controller, which handles input information with tracking differentiator, estimates system uncertainties with extended state observer, and generates control variables by state feedback and compensation. The designed active disturbance rejection controller is robust to both internal dynamics and external disturbances. The bandwidth parameter of extended state observer is optimized by the artificial bee colony algorithm so as to improve the performance of attitude control system. A series of simulation experiment results demonstrate the performance superiorities of the proposed robust fault-tolerant control algorithm.

  1. A New Adaptive Control for Five-Phase Fault-Tolerant Flux-Switching Permanent Magnet Motor

    Directory of Open Access Journals (Sweden)

    Hongyu Tang

    2016-01-01

    Full Text Available The five-phase fault-tolerant flux-switching permanent magnet (FT-FSPM motor can offer high efficiency and high fault-tolerant capability. In this paper, its operation principle is presented briefly and its mathematical model is derived. Further, a new adaptive control for an FT-FSPM motor, based on the backstepping method and the sliding mode control strategy, is proposed. According to the backstepping method, the current controllers and voltage control laws are designed to track the speed and minimize the current static error, which enhance the dynamic response and the ability to suppress external disturbances. In order to overcome the influence of parameter variations, according to sliding mode control theory, the virtual control variables and the adaptive algorithm are utilized to approach uncertainty terms. Three Lyapunov functions are designed, and the stability of the closed-loop system is analyzed in detail. Finally, both simulation and experimental results are presented to verify the proposed control method.

  2. Mobile medical and health apps: state of the art, concerns, regulatory control and certification

    Science.gov (United States)

    Boulos, Maged N. Kamel; Brewer, Ann C.; Karimkhani, Chante; Buller, David B.; Dellavalle, Robert P.

    2014-01-01

    This paper examines the state of the art in mobile clinical and health-related apps. A 2012 estimate puts the number of health-related apps at no fewer than 40,000, as healthcare professionals and consumers continue to express concerns about the quality of many apps, calling for some form of app regulatory control or certification to be put in place. We describe the range of apps on offer as of 2013, and then present a brief survey of evaluation studies of medical and health-related apps that have been conducted to date, covering a range of clinical disciplines and topics. Our survey includes studies that highlighted risks, negative issues and worrying deficiencies in existing apps. We discuss the concept of ‘apps as a medical device’ and the relevant regulatory controls that apply in USA and Europe, offering examples of apps that have been formally approved using these mechanisms. We describe the online Health Apps Library run by the National Health Service in England and the calls for a vetted medical and health app store. We discuss the ingredients for successful apps beyond the rather narrow definition of ‘apps as a medical device’. These ingredients cover app content quality, usability, the need to match apps to consumers’ general and health literacy levels, device connectivity standards (for apps that connect to glucometers, blood pressure monitors, etc.), as well as app security and user privacy. ‘Happtique Health App Certification Program’ (HACP), a voluntary app certification scheme, successfully captures most of these desiderata, but is solely focused on apps targeting the US market. HACP, while very welcome, is in ways reminiscent of the early days of the Web, when many “similar” quality benchmarking tools and codes of conduct for information publishers were proposed to appraise and rate online medical and health information. It is probably impossible to rate and police every app on offer today, much like in those early days of the Web

  3. Radiological safety in extraction of rare earths in India: regulatory control

    International Nuclear Information System (INIS)

    Sinha, S.; Bhattacharya, R.

    2011-01-01

    The term 'rare earths' refers to a group of f-block elements in the periodic table including those with atomic numbers 57 (Lanthanum) to 71 (Lutetium), as well as the transition metals Yttrium (39) and Scandium (21). Economically extractable concentrations of rare earths are found in minerals such as monazite, bastnaesite, cerites, xenotime etc. Of these, monazite forms the main source for rare earths in India, which along with other heavy minerals is found abundantly in the coastal beach sands. However, in addition to rare earths, monazite also contains 0.35% U 3 O 8 and 8-9% ThO 2 . Hence, extraction of rare earths involves chemical separation of the rare earths from thorium and uranium which are radioactive. The processing and extraction of rare earths from monazite therefore invariably results in occupational radiation exposure to the workers involved in these operations. In addition, in the process of removal of radioactivity from rare earths, radioactive solid waste gets generated which has 2 2 8Ra concentration in the range 2000-5000 Bq/g. Unregulated disposal of such high active waste would not only result in contamination of the soil but the radionuclides would eventually enter the food chain and lead to internal exposure of the general public. Therefore such facilities involved in recovery of rare earths from monazite attract the provisions of radiological safety regulations. Atomic Energy Regulatory Board of India has been enforcing the provisions of The Atomic Energy (Radiation Protection) Rules, 2004 and The Atomic Energy (Safe Disposal of Radioactive Waste) Rules, 1987 in these facilities. This paper shall discuss the associated radiological hazard involved in recovery of rare earths from monazite. It shall also highlight the regulatory requirements for controlling the occupational exposure of workers during design stage such as requirements on lay out of the building, ventilation, containment of radioactivity, etc and also the during operational

  4. Effects of Combining a Brief Cognitive Intervention with Transcranial Direct Current Stimulation on Pain Tolerance: A Randomized Controlled Pilot Study.

    Science.gov (United States)

    Powers, Abigail; Madan, Alok; Hilbert, Megan; Reeves, Scott T; George, Mark; Nash, Michael R; Borckardt, Jeffrey J

    2018-04-01

    Cognitive behavioral therapy has been shown to be effective for treating chronic pain, and a growing literature shows the potential analgesic effects of minimally invasive brain stimulation. However, few studies have systematically investigated the potential benefits associated with combining approaches. The goal of this pilot laboratory study was to investigate the combination of a brief cognitive restructuring intervention and transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex in affecting pain tolerance. Randomized, double-blind, placebo-controlled laboratory pilot. Medical University of South Carolina. A total of 79 healthy adult volunteers. Subjects were randomized into one of six groups: 1) anodal tDCS plus a brief cognitive intervention (BCI); 2) anodal tDCS plus pain education; 3) cathodal tDCS plus BCI; 4) cathodal tDCS plus pain education; 5) sham tDCS plus BCI; and 6) sham tDCS plus pain education. Participants underwent thermal pain tolerance testing pre- and postintervention using the Method of Limits. A significant main effect for time (pre-post intervention) was found, as well as for baseline thermal pain tolerance (covariate) in the model. A significant time × group interaction effect was found on thermal pain tolerance. Each of the five groups that received at least one active intervention outperformed the group receiving sham tDCS and pain education only (i.e., control group), with the exception of the anodal tDCS + education-only group. Cathodal tDCS combined with the BCI produced the largest analgesic effect. Combining cathodal tDCS with BCI yielded the largest analgesic effect of all the conditions tested. Future research might find stronger interactive effects of combined tDCS and a cognitive intervention with larger doses of each intervention. Because this controlled laboratory pilot employed an acute pain analogue and the cognitive intervention did not authentically represent cognitive behavioral

  5. Melatonin for Sleep in Children with Autism: A Controlled Trial Examining Dose, Tolerability, and Outcomes

    Science.gov (United States)

    Malow, Beth; Adkins, Karen W.; McGrew, Susan G.; Wang, Lily; Goldman, Suzanne E.; Fawkes, Diane; Burnette, Courtney

    2012-01-01

    Supplemental melatonin has shown promise in treating sleep onset insomnia in children with autism spectrum disorders (ASD). Twenty-four children, free of psychotropic medications, completed an open-label dose-escalation study to assess dose-response, tolerability, safety, feasibility of collecting actigraphy data, and ability of outcome measures…

  6. Radiological and administrative criteria and procedures required by the Radiation Protection Ordinance for exemption from regulatory control

    International Nuclear Information System (INIS)

    Birkholz, W.

    2000-01-01

    The system of required radioactivity measurements and limits as well as methods, based on the 10 μSv concept, constitutes the regulatory regime for exemption of radioactive waste materials from regulatory control according to atomic energy law. The methods and administrative procedures are suitable both for smaller amounts of materials, such as those resulting from the use of radioactive substances in scientific research and medical applications, and for the large waste volumes emanating from the dismantling of nuclear installations. The system provided for in the Radiation Protection Ordinance ensures harmonized administrative action of all public authorities involved. (orig./CB) [de

  7. 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.

  8. Tissue-specific control of latent CMV reactivation by regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Maha Almanan

    2017-08-01

    Full Text Available Cytomegalovirus (CMV causes a persistent, lifelong infection. CMV persists in a latent state and undergoes intermittent subclinical viral reactivation that is quelled by ongoing T cell responses. While T cells are critical to maintain control of infection, the immunological factors that promote CMV persistence remain unclear. Here, we investigated the role of regulatory T cells (Treg in a mouse model of latent CMV infection using Foxp3-diphtheria toxin receptor (Foxp3-DTR mice. Eight months after infection, MCMV had established latency in the spleen, salivary gland, lung, and pancreas, which was accompanied by an increased frequency of Treg. Administration of diphtheria toxin (DT after establishment of latency efficiently depleted Treg and drove a significant increase in the numbers of functional MCMV-specific CD4+ and CD8+ T cells. Strikingly, Treg depletion decreased the number of animals with reactivatable latent MCMV in the spleen. Unexpectedly, in the same animals, ablation of Treg drove a significant increase in viral reactivation in the salivary gland that was accompanied with augmented local IL-10 production by Foxp3-CD4+T cells. Further, neutralization of IL-10 after Treg depletion significantly decreased viral load in the salivary gland. Combined, these data show that Treg have divergent control of MCMV infection depending upon the tissue. In the spleen, Treg antagonize CD8+ effector function and promote viral persistence while in the salivary gland Treg prevent IL-10 production and limit viral reactivation and replication. These data provide new insights into the organ-specific roles of Treg in controlling the reactivation of latent MCMV infection.

  9. Fault tolerant control with torque limitation based on fault mode for ten-phase permanent magnet synchronous motor

    Directory of Open Access Journals (Sweden)

    Guo Hong

    2015-10-01

    Full Text Available This paper proposes a novel fault tolerant control with torque limitation based on the fault mode for the ten-phase permanent magnet synchronous motor (PMSM under various open-circuit and short-circuit fault conditions, which includes the optimal torque control and the torque limitation control based on the fault mode. The optimal torque control is adopted to guarantee the ripple-free electromagnetic torque operation for the ten-phase motor system under the post-fault condition. Furthermore, we systematically analyze the load capacity of the ten-phase motor system under different fault modes. And a torque limitation control approach based on the fault mode is proposed, which was not available earlier. This approach is able to ensure the safety operation of the faulted motor system in long operating time without causing the overheat fault. The simulation result confirms that the proposed fault tolerant control for the ten-phase motor system is able to guarantee the ripple-free electromagnetic torque and the safety operation in long operating time under the normal and fault conditions.

  10. Core transcriptional regulatory circuit controlled by the TAL1 complex in human T cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Sanda, Takaomi; Lawton, Lee N; Barrasa, M Inmaculada; Fan, Zi Peng; Kohlhammer, Holger; Gutierrez, Alejandro; Ma, Wenxue; Tatarek, Jessica; Ahn, Yebin; Kelliher, Michelle A; Jamieson, Catriona H M; Staudt, Louis M; Young, Richard A; Look, A Thomas

    2012-08-14

    The oncogenic transcription factor TAL1/SCL is aberrantly expressed in over 40% of cases of human T cell acute lymphoblastic leukemia (T-ALL), emphasizing its importance in the molecular pathogenesis of T-ALL. Here we identify the core transcriptional regulatory circuit controlled by TAL1 and its regulatory partners HEB, E2A, LMO1/2, GATA3, and RUNX1. We show that TAL1 forms a positive interconnected autoregulatory loop with GATA3 and RUNX1 and that the TAL1 complex directly activates the MYB oncogene, forming a positive feed-forward regulatory loop that reinforces and stabilizes the TAL1-regulated oncogenic program. One of the critical downstream targets in this circuitry is the TRIB2 gene, which is oppositely regulated by TAL1 and E2A/HEB and is essential for the survival of T-ALL cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Regulatory role for the memory B cell as suppressor-inducer of feedback control

    International Nuclear Information System (INIS)

    Kennedy, M.W.; Thomas, D.B.

    1983-01-01

    A regulatory role is proposed for the antigen-responsive B cell, as suppressor-inducer of feedback control during the secondary response in vivo. In a double adoptive transfer of memory cells primed to a thymus-dependent antigen from one irradiated host to another, antigen-specific suppressors are generated after a critical time in the primary recipient, able to entirely ablate a secondary anti-hapten response. Positive cell selection in the fluorescence-activated cell sorter confirmed that suppression was mediated by an Lyt-2+ T cell; however, positively selected B cells were also inhibitory and able to induce suppressors in a carrier-specific manner: B hapten induced suppressors in a carrier-primed population, and B carrier induced suppressors in a hapten-carrier population. At the peak of the antibody response in the primary host, memory B cells and their progeny were unable to differentiate further to plasma cells due to their intrinsic suppressor-inducer activity, but this autoregulatory circuit could be severed by adoptive transfer to carrier-primed, X-irradiated recipients

  12. HAND2 Target Gene Regulatory Networks Control Atrioventricular Canal and Cardiac Valve Development.

    Science.gov (United States)

    Laurent, Frédéric; Girdziusaite, Ausra; Gamart, Julie; Barozzi, Iros; Osterwalder, Marco; Akiyama, Jennifer A; Lincoln, Joy; Lopez-Rios, Javier; Visel, Axel; Zuniga, Aimée; Zeller, Rolf

    2017-05-23

    The HAND2 transcriptional regulator controls cardiac development, and we uncover additional essential functions in the endothelial to mesenchymal transition (EMT) underlying cardiac cushion development in the atrioventricular canal (AVC). In Hand2-deficient mouse embryos, the EMT underlying AVC cardiac cushion formation is disrupted, and we combined ChIP-seq of embryonic hearts with transcriptome analysis of wild-type and mutants AVCs to identify the functionally relevant HAND2 target genes. The HAND2 target gene regulatory network (GRN) includes most genes with known functions in EMT processes and AVC cardiac cushion formation. One of these is Snai1, an EMT master regulator whose expression is lost from Hand2-deficient AVCs. Re-expression of Snai1 in mutant AVC explants partially restores this EMT and mesenchymal cell migration. Furthermore, the HAND2-interacting enhancers in the Snai1 genomic landscape are active in embryonic hearts and other Snai1-expressing tissues. These results show that HAND2 directly regulates the molecular cascades initiating AVC cardiac valve development. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  13. A two-component regulatory system controls autoregulated serpin expression in Bifidobacterium breve UCC2003.

    Science.gov (United States)

    Alvarez-Martin, Pablo; O'Connell Motherway, Mary; Turroni, Francesca; Foroni, Elena; Ventura, Marco; van Sinderen, Douwe

    2012-10-01

    This work reports on the identification and molecular characterization of a two-component regulatory system (2CRS), encoded by serRK, which is believed to control the expression of the ser(2003) locus in Bifidobacterium breve UCC2003. The ser(2003) locus consists of two genes, Bbr_1319 (sagA) and Bbr_1320 (serU), which are predicted to encode a hypothetical membrane-associated protein and a serpin-like protein, respectively. The response regulator SerR was shown to bind to the promoter region of ser(2003), and the probable recognition sequence of SerR was determined by a combinatorial approach of in vitro site-directed mutagenesis coupled to transcriptional fusion and electrophoretic mobility shift assays (EMSAs). The importance of the serRK 2CRS in the response of B. breve to protease-mediated induction was confirmed by generating a B. breve serR insertion mutant, which was shown to exhibit altered ser(2003) transcriptional induction patterns compared to the parent strain, UCC2003. Interestingly, the analysis of a B. breve serU mutant revealed that the SerRK signaling pathway appears to include a SerU-dependent autoregulatory loop.

  14. A Regulatory Circuit Composed of a Transcription Factor, IscR, and a Regulatory RNA, RyhB, Controls Fe-S Cluster Delivery.

    Science.gov (United States)

    Mandin, Pierre; Chareyre, Sylvia; Barras, Frédéric

    2016-09-20

    Fe-S clusters are cofactors conserved through all domains of life. Once assembled by dedicated ISC and/or SUF scaffolds, Fe-S clusters are conveyed to their apo-targets via A-type carrier proteins (ATCs). Escherichia coli possesses four such ATCs. ErpA is the only ATC essential under aerobiosis. Recent studies reported a possible regulation of the erpA mRNA by the small RNA (sRNA) RyhB, which controls the expression of many genes under iron starvation. Surprisingly, erpA has not been identified in recent transcriptomic analysis of the iron starvation response, thus bringing into question the actual physiological significance of the putative regulation of erpA by RyhB. Using an sRNA library, we show that among 26 sRNAs, only RyhB represses the expression of an erpA-lacZ translational fusion. We further demonstrate that this repression occurs during iron starvation. Using mutational analysis, we show that RyhB base pairs to the erpA mRNA, inducing its disappearance. In addition, IscR, the master regulator of Fe-S homeostasis, represses expression of erpA at the transcriptional level when iron is abundant, but depleting iron from the medium alleviates this repression. The conjunction of transcriptional derepression by IscR and posttranscriptional repression by RyhB under Fe-limiting conditions is best described as an incoherent regulatory circuit. This double regulation allows full expression of erpA at iron concentrations for which Fe-S biogenesis switches from the ISC to the SUF system. We further provide evidence that this regulatory circuit coordinates ATC usage to iron availability. Regulatory small RNAs (sRNAs) have emerged as major actors in the control of gene expression in the last few decades. Relatively little is known about how these regulators interact with classical transcription factors to coordinate genetic responses. We show here how an sRNA, RyhB, and a transcription factor, IscR, regulate expression of an essential gene, erpA, in the bacterium E

  15. Development of a Quantitative Method for Evaluating the Efficacy of Cyber Security Controls in NPPs based on Intrusion Tolerant Concept

    International Nuclear Information System (INIS)

    Lee, Chanyoung; Seong, Poong Hyun

    2017-01-01

    Digital I and C systems have been developed and installed in nuclear power plants (NPPs). However, due to installation of digital I and C systems, cyber security concerns are increasing in the nuclear industry. In order to provide useful information about cyber security issues, many regulatory documents, guides and standards were already published in the nuclear industry. The documents include cyber security plans, methods for cyber security assessments and comprehensive set of security controls. In order for useful information about cyber security issues, many regulatory documents, guides and standards have been already published in the nuclear industry. However, there are still difficulties when it comes to deciding which security controls are needed and to defining appropriate security control requirements. It is because practical examples for the application of security controls have not been available to system designers and there is a lack of means for estimating the effectiveness of security controls. In this regard, this paper suggested a framework to quantitatively evaluate how much cyber security is improved when specific cyber security controls are applied in NPPs.

  16. Decoupling control of a five-phase fault-tolerant permanent magnet motor by radial basis function neural network inverse

    Science.gov (United States)

    Chen, Qian; Liu, Guohai; Xu, Dezhi; Xu, Liang; Xu, Gaohong; Aamir, Nazir

    2018-05-01

    This paper proposes a new decoupled control for a five-phase in-wheel fault-tolerant permanent magnet (IW-FTPM) motor drive, in which radial basis function neural network inverse (RBF-NNI) and internal model control (IMC) are combined. The RBF-NNI system is introduced into original system to construct a pseudo-linear system, and IMC is used as a robust controller. Hence, the newly proposed control system incorporates the merits of the IMC and RBF-NNI methods. In order to verify the proposed strategy, an IW-FTPM motor drive is designed based on dSPACE real-time control platform. Then, the experimental results are offered to verify that the d-axis current and the rotor speed are successfully decoupled. Besides, the proposed motor drive exhibits strong robustness even under load torque disturbance.

  17. Decentralized Sliding Mode Observer Based Dual Closed-Loop Fault Tolerant Control for Reconfigurable Manipulator against Actuator Failure.

    Directory of Open Access Journals (Sweden)

    Bo Zhao

    Full Text Available This paper considers a decentralized fault tolerant control (DFTC scheme for reconfigurable manipulators. With the appearance of norm-bounded failure, a dual closed-loop trajectory tracking control algorithm is proposed on the basis of the Lyapunov stability theory. Characterized by the modularization property, the actuator failure is estimated by the proposed decentralized sliding mode observer (DSMO. Moreover, the actuator failure can be treated in view of the local joint information, so its control performance degradation is independent of other normal joints. In addition, the presented DFTC scheme is significantly simplified in terms of the structure of the controller due to its dual closed-loop architecture, and its feasibility is highly reflected in the control of reconfigurable manipulators. Finally, the effectiveness of the proposed DFTC scheme is demonstrated using simulations.

  18. Decentralized Sliding Mode Observer Based Dual Closed-Loop Fault Tolerant Control for Reconfigurable Manipulator against Actuator Failure

    Science.gov (United States)

    Zhao, Bo; Li, Yuanchun

    2015-01-01

    This paper considers a decentralized fault tolerant control (DFTC) scheme for reconfigurable manipulators. With the appearance of norm-bounded failure, a dual closed-loop trajectory tracking control algorithm is proposed on the basis of the Lyapunov stability theory. Characterized by the modularization property, the actuator failure is estimated by the proposed decentralized sliding mode observer (DSMO). Moreover, the actuator failure can be treated in view of the local joint information, so its control performance degradation is independent of other normal joints. In addition, the presented DFTC scheme is significantly simplified in terms of the structure of the controller due to its dual closed-loop architecture, and its feasibility is highly reflected in the control of reconfigurable manipulators. Finally, the effectiveness of the proposed DFTC scheme is demonstrated using simulations. PMID:26181826

  19. Characteristic Analysis and Fault-Tolerant Control of Circulating Current for Modular Multilevel Converters under Sub-Module Faults

    Directory of Open Access Journals (Sweden)

    Wen Wu

    2017-11-01

    Full Text Available A modular multilevel converter (MMC is considered to be a promising topology for medium- or high-power applications. However, a significantly increased amount of sub-modules (SMs in each arm also increase the risk of failures. Focusing on the fault-tolerant operation issue for the MMC under SM faults, the operation characteristics of MMC with different numbers of faulty SMs in the arms are analyzed and summarized in this paper. Based on the characteristics, a novel circulating current-suppressing (CCS fault-tolerant control strategy comprised of a basic control unit (BCU and virtual resistance compensation control unit (VRCCU in two parts is proposed, which has three main features: (i it can suppress the multi-different frequency components of the circulating current under different SM fault types simultaneously; (ii it can help fast limiting of the transient fault current caused at the faulty SM bypassed moment; and (iii it does not need extra communication systems to acquire the information of the number of faulty SMs. Moreover, by analyzing the stability performance of the proposed controller using the Root-Locus criterion, the election principle of the value of virtual resistance is revealed. Finally, the efficiency of the control strategy is confirmed with the simulation and experiment studies under different fault conditions.

  20. Integration of error tolerance into the design of control rooms of nuclear power plants

    International Nuclear Information System (INIS)

    Sepanloo, Kamran

    1998-08-01

    Many complex technological systems' failures have been attributed to human errors. Today, based on extensive research on the role of human element in technological systems it is known that human error can not totally be eliminated in modern, flexible, or changing work environments by conventional style design strategies(e.g. defence in depth), or better instructions nor should they be. Instead, the operators' ability to explore degrees of freedom should be supported and means for recovering from the effects of errors should be included. This calls for innovative error tolerant design of technological systems. Integration of error tolerant concept into the design, construction, startup, and operation of nuclear power plants provides an effective means of reducing human error occurrence during all stages of life of it and therefore leads to considerable enhancement of plant's safety

  1. Biochemical Tolerance During Low Dose Propylene Glycol Exposure in Neonates: A Formulation-Controlled Evaluation

    Directory of Open Access Journals (Sweden)

    Aida Kulo

    2012-07-01

    Full Text Available Background and purpose of the study: Propylene glycol (PG is a frequently co-administered solvent in formulations administered to neonates, but reports on its (intolerance are limited. We aimed to report on renal, metabolic and hepatic tolerance before, during and following intravenous (iv PG-paracetamol exposure and compared these data with similar datasets reported in literature on neonates exposed to PG without paracetamol or paracetamol without PG.Methods: Renal (diuresis, creatinemia, sodium, metabolic (Base Excess, Anion Gap, lactate, bicarbonate and hepatic (liver enzymes, bilirubinemia indicators before, during and following iv paracetamol-PG exposure in neonates as included in the PARANEO (paracetamol in neonates study (intra-individual trends, ANOVA were collected and analysed.Comparison with observations collected in cases exposed to either iv phenobarbital-PG or iv paracetamol-mannitol (inter-individual comparison, Mann Whitney-U test were made. Results: PG exposure (median 34.1 mg/kg/24 h did not affect postnatal renal, metabolic and hepatic adaptations in 60 cases exposed to paracetamol-PG. These indicators were similar when compared to 29 cases exposed to phenobarbital- PG or 172 cases exposed to paracetamol-mannitol.Major conclusion: Based on observations in 89 neonates, low dose PG exposure was tolerated well. Studies on PG pharmacokinetics and its covariates are needed to estimate the upper level of PG tolerance in neonates.

  2. Small regulatory RNAs control the multi-cellular adhesive lifestyle of Escherichia coli

    DEFF Research Database (Denmark)

    Jørgensen, Mikkel Girke; Nielsen, Jesper Sejrup; Boysen, Anders

    2012-01-01

    Small regulatory RNA molecules have recently been recognized as important regulatory elements of developmental processes in both eukaryotes and bacteria. We here describe a striking example in Escherichia coli that can switch between a single-cell motile lifestyle and a multi-cellular, sessile....... Our demonstration that basal expression of each of the three RNA species is sufficient to downregulate CsgD synthesis and prevent curli formation indicates that all play a prominent role in the curli regulatory network. Our findings provide the first clue as to how the Rcs signalling pathway...... negatively regulates curli synthesis and increase the number of small regulatory RNAs that act directly on the csgD mRNA to five....

  3. Approach for assessing the effectiveness of regulatory control in Peru using performance indicators

    International Nuclear Information System (INIS)

    Ramirez Quijada, R.

    1998-01-01

    The paper is intended to make an approach for assessing the effectiveness of regulatory activities in Peru by using of performance indicators for each of the activities developed pursuant their responsibilities. So inspections, authorizations, enforcement and regulation activities are qualified by levels of attainments and then assessed independently to rise specific issues. The general conclusion is that regulatory activities seems to be acceptable but some improvements are needed in order to reach a good level of performance. (author)

  4. YF22 Model With On-Board On-Line Learning Microprocessors-Based Neural Algorithms for Autopilot and Fault-Tolerant Flight Control Systems

    National Research Council Canada - National Science Library

    Napolitano, Marcello

    2002-01-01

    This project focused on investigating the potential of on-line learning 'hardware-based' neural approximators and controllers to provide fault tolerance capabilities following sensor and actuator failures...

  5. Tolerance induced by anti-DNA Ig peptide in (NZB×NZW)F1 lupus mice impinges on the resistance of effector T cells to suppression by regulatory T cells.

    Science.gov (United States)

    Yu, Yiyun; Liu, Yaoyang; Shi, Fu-Dong; Zou, Hejian; Hahn, Bevra H; La Cava, Antonio

    2012-03-01

    We have previously shown that immune tolerance induced by the anti-DNA Ig peptide pCons in (NZB×NZW)F(1) (NZB/W) lupus mice prolonged survival of treated animals and delayed the appearance of autoantibodies and glomerulonephritis. Part of the protection conferred by pCons could be ascribed to the induction of regulatory T cells (T(Reg)) that suppressed the production of anti-DNA antibodies in a p38 MAPK-dependent fashion. Here we show that another effect of pCons in the induction of immune tolerance in NZB/W lupus mice is the facilitation of effector T cell suppression by T(Reg). These new findings indicate that pCons exerts protective effects in NZB/W lupus mice by differentially modulating the activity of different T cell subsets, implying new considerations in the design of T(Reg)-based approaches to modulate T cell autoreactivity in SLE. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Indirect adaptive fuzzy fault-tolerant tracking control for MIMO nonlinear systems with actuator and sensor failures.

    Science.gov (United States)

    Bounemeur, Abdelhamid; Chemachema, Mohamed; Essounbouli, Najib

    2018-05-10

    In this paper, an active fuzzy fault tolerant tracking control (AFFTTC) scheme is developed for a class of multi-input multi-output (MIMO) unknown nonlinear systems in the presence of unknown actuator faults, sensor failures and external disturbance. The developed control scheme deals with four kinds of faults for both sensors and actuators. The bias, drift, and loss of accuracy additive faults are considered along with the loss of effectiveness multiplicative fault. A fuzzy adaptive controller based on back-stepping design is developed to deal with actuator failures and unknown system dynamics. However, an additional robust control term is added to deal with sensor faults, approximation errors, and external disturbances. Lyapunov theory is used to prove the stability of the closed loop system. Numerical simulations on a quadrotor are presented to show the effectiveness of the proposed approach. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Fault Tolerant Operation of ISOP Multicell Dc-Dc Converter Using Active Gate Controlled SiC Protection Switch

    Directory of Open Access Journals (Sweden)

    Yusuke Hayashi

    2016-01-01

    Full Text Available An active gate controlled semiconductor protection switch using SiC-MOSFET is proposed to achieve the fault tolerant operation of ISOP (Input Series and Output Parallel connected multicell dc-dc converter. The SiC-MOSFET with high temperature capability simplifies the configuration of the protection circuit, and its on-resistance control by the active gate controller realizes the smooth protection without the voltage and the current surges. The first laboratory prototype of the protection switch is fabricated by using a SiC-MOSFET with a high frequency buck chopper for the active gate controller. The effectiveness of the proposed protection switch is verified, taking the impact of the volume reduction into account.

  8. Dual regulatory switch confers tighter control on HtrA2 proteolytic activity.

    Science.gov (United States)

    Singh, Nitu; D'Souza, Areetha; Cholleti, Anuradha; Sastry, G Madhavi; Bose, Kakoli

    2014-05-01

    High-temperature requirement protease A2 (HtrA2), a multitasking serine protease that is involved in critical biological functions and pathogenicity, such as apoptosis and cancer, is a potent therapeutic target. It is established that the C-terminal post-synaptic density protein, Drosophila disc large tumor suppressor, zonula occludens-1 protein (PDZ) domain of HtrA2 plays pivotal role in allosteric modulation, substrate binding and activation, as commonly reported in other members of this family. Interestingly, HtrA2 exhibits an additional level of functional modulation through its unique N-terminus, as is evident from 'inhibitor of apoptosis proteins' binding and cleavage. This phenomenon emphasizes multiple activation mechanisms, which so far remain elusive. Using conformational dynamics, binding kinetics and enzymology studies, we addressed this complex behavior with respect to defining its global mode of regulation and activity. Our findings distinctly demonstrate a novel N-terminal ligand-mediated triggering of an allosteric switch essential for transforming HtrA2 to a proteolytically competent state in a PDZ-independent yet synergistic activation process. Dynamic analyses suggested that it occurs through a series of coordinated structural reorganizations at distal regulatory loops (L3, LD, L1), leading to a population shift towards the relaxed conformer. This precise synergistic coordination among different domains might be physiologically relevant to enable tighter control upon HtrA2 activation for fostering its diverse cellular functions. Understanding this complex rheostatic dual switch mechanism offers an opportunity for targeting various disease conditions with tailored site-specific effector molecules. © 2014 FEBS.

  9. A Regulatory Circuit Composed of a Transcription Factor, IscR, and a Regulatory RNA, RyhB, Controls Fe-S Cluster Delivery

    Directory of Open Access Journals (Sweden)

    Pierre Mandin

    2016-09-01

    Full Text Available Fe-S clusters are cofactors conserved through all domains of life. Once assembled by dedicated ISC and/or SUF scaffolds, Fe-S clusters are conveyed to their apo-targets via A-type carrier proteins (ATCs. Escherichia coli possesses four such ATCs. ErpA is the only ATC essential under aerobiosis. Recent studies reported a possible regulation of the erpA mRNA by the small RNA (sRNA RyhB, which controls the expression of many genes under iron starvation. Surprisingly, erpA has not been identified in recent transcriptomic analysis of the iron starvation response, thus bringing into question the actual physiological significance of the putative regulation of erpA by RyhB. Using an sRNA library, we show that among 26 sRNAs, only RyhB represses the expression of an erpA-lacZ translational fusion. We further demonstrate that this repression occurs during iron starvation. Using mutational analysis, we show that RyhB base pairs to the erpA mRNA, inducing its disappearance. In addition, IscR, the master regulator of Fe-S homeostasis, represses expression of erpA at the transcriptional level when iron is abundant, but depleting iron from the medium alleviates this repression. The conjunction of transcriptional derepression by IscR and posttranscriptional repression by RyhB under Fe-limiting conditions is best described as an incoherent regulatory circuit. This double regulation allows full expression of erpA at iron concentrations for which Fe-S biogenesis switches from the ISC to the SUF system. We further provide evidence that this regulatory circuit coordinates ATC usage to iron availability.

  10. Control of microstructure to increase the tolerance of zirconium alloys to hydride cracking

    International Nuclear Information System (INIS)

    Coleman, C.E.; Sagat, S.; Amouzouvi, K.F.

    1987-12-01

    The microstructure of Zr-2.5 Nb has been altered in three ways in attempts to increase the alloy's tolerance to delayed hydride cracking, namely by breaking up the β-phase which reduces diffusivity of hydrogen and decreases crack velocity, by means of a gettering element (yttrium) which reduces susceptibility to cracking although the yttrium alloy has low toughness and poor corrosion resistance, and by reducing the number of basal plane normals in the main stressing direction which improves resistance to crack growth

  11. Fault tolerant, multiplexed control rod position detection and indication system for nuclear power plants

    International Nuclear Information System (INIS)

    Dufek, W.L.; Jelovich, J.J.; Neuner, J.A.

    1977-01-01

    The majority of Westinghouse nuclear plants placed in service thus far have incorporated a Rod Position Indication system based upon an analog design philosophy. This system, while meeting all functional and accuracy requirements, has proven somewhat cumbersome, particularly in the area of initial field calibration and maintenance. This paper describes a new Digital Rod Position Indication system (DRPI) developed for use with pressurized water reactors. The system is based upon a digital design philosophy and meets all previous design constraints and environmental requirements. Further, fault tolerance, improved accuracy, interference from adjacent rods and the elimination of adjustments and calibration has been provided

  12. Risk Informed Approach for Nuclear Security Measures for Nuclear and Other Radioactive Material out of Regulatory Control. Implementing Guide

    International Nuclear Information System (INIS)

    2015-01-01

    This publication provides guidance to States for developing a risk informed approach and for conducting threat and risk assessments as the basis for the design and implementation of sustainable nuclear security systems and measures for prevention of, detection of, and response to criminal and intentional unauthorised acts involving nuclear and other radioactive material out of regulatory control. It describes concepts and methodologies for a risk informed approach, including identification and assessment of threats, targets, and potential consequences; threat and risk assessment methodologies, and the use of risk informed approaches as the basis for informing the development and implementation of nuclear security systems and measures. The publication is an Implementing Guide within the IAEA Nuclear Security Series and is intended for use by national policy makers, law enforcement agencies and experts from competent authorities and other relevant organizations involved in the establishment, implementation, maintenance or sustainability of nuclear security systems and measures related to nuclear and other radioactive material out of regulatory control

  13. Fault-Tolerant Control of ANPC Three-Level Inverter Based on Order-Reduction Optimal Control Strategy under Multi-Device Open-Circuit Fault.

    Science.gov (United States)

    Xu, Shi-Zhou; Wang, Chun-Jie; Lin, Fang-Li; Li, Shi-Xiang

    2017-10-31

    The multi-device open-circuit fault is a common fault of ANPC (Active Neutral-Point Clamped) three-level inverter and effect the operation stability of the whole system. To improve the operation stability, this paper summarized the main solutions currently firstly and analyzed all the possible states of multi-device open-circuit fault. Secondly, an order-reduction optimal control strategy was proposed under multi-device open-circuit fault to realize fault-tolerant control based on the topology and control requirement of ANPC three-level inverter and operation stability. This control strategy can solve the faults with different operation states, and can works in order-reduction state under specific open-circuit faults with specific combined devices, which sacrifices the control quality to obtain the stability priority control. Finally, the simulation and experiment proved the effectiveness of the proposed strategy.

  14. A Soft Sensor-Based Fault-Tolerant Control on the Air Fuel Ratio of Spark-Ignition Engines

    Directory of Open Access Journals (Sweden)

    Yu-Jia Zhai

    2017-01-01

    Full Text Available The air/fuel ratio (AFR regulation for spark-ignition (SI engines has been an essential and challenging control problem for engineers in the automotive industry. The feed-forward and feedback scheme has been investigated in both academic research and industrial application. The aging effect can often cause an AFR sensor fault in the feedback loop, and the AFR control performance will degrade consequently. In this research, a new control scheme on AFR with fault-tolerance is proposed by using an artificial neural network model based on fault detection and compensation, which can provide the satisfactory AFR regulation performance at the stoichiometric value for the combustion process, given a certain level of misreading of the AFR sensor.

  15. Adaptive Fuzzy Output-Constrained Fault-Tolerant Control of Nonlinear Stochastic Large-Scale Systems With Actuator Faults.

    Science.gov (United States)

    Li, Yongming; Ma, Zhiyao; Tong, Shaocheng

    2017-09-01

    The problem of adaptive fuzzy output-constrained tracking fault-tolerant control (FTC) is investigated for the large-scale stochastic nonlinear systems of pure-feedback form. The nonlinear systems considered in this paper possess the unstructured uncertainties, unknown interconnected terms and unknown nonaffine nonlinear faults. The fuzzy logic systems are employed to identify the unknown lumped nonlinear functions so that the problems of structured uncertainties can be solved. An adaptive fuzzy state observer is designed to solve the nonmeasurable state problem. By combining the barrier Lyapunov function theory, adaptive decentralized and stochastic control principles, a novel fuzzy adaptive output-constrained FTC approach is constructed. All the signals in the closed-loop system are proved to be bounded in probability and the system outputs are constrained in a given compact set. Finally, the applicability of the proposed controller is well carried out by a simulation example.

  16. Regulatory dendritic cells in autoimmunity: A comprehensive review.

    Science.gov (United States)

    Liu, Juan; Cao, Xuetao

    2015-09-01

    Dendritic cells (DCs) are professional antigen-presenting cells (APC) with significant phenotypic heterogeneity and functional plasticity. DCs play crucial roles in initiating effective adaptive immune responses for elimination of invading pathogens and also in inducing immune tolerance toward harmless components to maintain immune homeostasis. The regulatory capacity of DCs depends on their immature state and distinct subsets, yet not restricted to the immature state and one specialized subset. The tolerogenicity of DC is controlled by a complex network of environmental signals and cellular intrinsic mechanisms. Regulatory DCs play an important role in the maintenance of immunological tolerance via the induction of T cell unresponsiveness or apoptosis, and generation of regulatory T cells. DCs play essential roles in driving autoimmunity via promoting the activation of effector T cells such as T helper 1 and T helper 17 cells, and/or suppressing the generation of regulatory T cells. Besides, a breakdown of DCs-mediated tolerance due to abnormal environmental signals or breakdown of intrinsic regulatory mechanisms is closely linked with the pathogenesis of autoimmune diseases. Novel immunotherapy taking advantage of the tolerogenic potential of regulatory DCs is being developed for treatment of autoimmune diseases. In this review, we will describe the current understanding on the generation of regulatory DC and the role of regulatory DCs in promoting tolerogenic immune responses and suppressing autoimmune responses. The emerging roles of DCs dysfunction in the pathogenesis of autoimmune diseases and the potential application of regulatory DCs in the treatment of autoimmune diseases will also be discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Organization and implementation of a national programme of regulatory control of sources in Estonia

    International Nuclear Information System (INIS)

    Filippova, I.

    1998-01-01

    The application of ionizing radiation and radioactive material in fields such as medicine, industry, teaching and research is constantly increasing. Consequently, any country using ionizing radiation and radioactive material in these applications must ensure that they are used safely. In order to achieve this goal a country must establish appropriate national infrastructure related to radiation protection and safety. This requires appropriate regulatory mechanism together with an enforcement ability. The national infrastructure adopted in a country will depend on the actual needs of the country, the size and the complexity of the regulated practices and sources, as well as on the regulatory tradition in the country. The national infrastructure in Estonia comprises of three main components: legislation, regulatory authority, resources. (author)

  18. Antigen specific T-cell responses against tumor antigens are controlled by regulatory T cells in patients with prostate cancer.

    Science.gov (United States)

    Hadaschik, Boris; Su, Yun; Huter, Eva; Ge, Yingzi; Hohenfellner, Markus; Beckhove, Philipp

    2012-04-01

    Immunotherapy is a promising approach in an effort to control castration resistant prostate cancer. We characterized tumor antigen reactive T cells in patients with prostate cancer and analyzed the suppression of antitumor responses by regulatory T cells. Peripheral blood samples were collected from 57 patients with histologically confirmed prostate cancer, 8 patients with benign prostatic hyperplasia and 16 healthy donors. Peripheral blood mononuclear cells were isolated and antigen specific interferon-γ secretion of isolated T cells was analyzed by enzyme-linked immunospot assay. T cells were functionally characterized and T-cell responses before and after regulatory T-cell depletion were compared. As test tumor antigens, a panel of 11 long synthetic peptides derived from a total of 8 tumor antigens was used, including prostate specific antigen and prostatic acid phosphatase. In patients with prostate cancer we noted a 74.5% effector T-cell response rate compared with only 25% in patients with benign prostatic hyperplasia and 31% in healthy donors. In most patients 2 or 3 tumor antigens were recognized. Comparing various disease stages there was a clear increase in the immune response against prostate specific antigens from intermediate to high risk tumors and castration resistant disease. Regulatory T-cell depletion led to a significant boost in effector T-cell responses against prostate specific antigen and prostatic acid phosphatase. Tumor specific effector T cells were detected in most patients with prostate cancer, especially those with castration resistant prostate cancer. Since effector T-cell responses against prostate specific antigens strongly increased after regulatory T-cell depletion, our results indicate that immunotherapy efficacy could be enhanced by decreasing regulatory T cells. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  19. Bayesian inference for the genetic control of water deficit tolerance in spring wheat by stochastic search variable selection.

    Science.gov (United States)

    Safari, Parviz; Danyali, Syyedeh Fatemeh; Rahimi, Mehdi

    2018-06-02

    Drought is the main abiotic stress seriously influencing wheat production. Information about the inheritance of drought tolerance is necessary to determine the most appropriate strategy to develop tolerant cultivars and populations. In this study, generation means analysis to identify the genetic effects controlling grain yield inheritance in water deficit and normal conditions was considered as a model selection problem in a Bayesian framework. Stochastic search variable selection (SSVS) was applied to identify the most important genetic effects and the best fitted models using different generations obtained from two crosses applying two water regimes in two growing seasons. The SSVS is used to evaluate the effect of each variable on the dependent variable via posterior variable inclusion probabilities. The model with the highest posterior probability is selected as the best model. In this study, the grain yield was controlled by the main effects (additive and non-additive effects) and epistatic. The results demonstrate that breeding methods such as recurrent selection and subsequent pedigree method and hybrid production can be useful to improve grain yield.

  20. Fault detection and fault tolerant control of a smart base isolation system with magneto-rheological damper

    International Nuclear Information System (INIS)

    Wang, Han; Song, Gangbing

    2011-01-01

    Fault detection and isolation (FDI) in real-time systems can provide early warnings for faulty sensors and actuator signals to prevent events that lead to catastrophic failures. The main objective of this paper is to develop FDI and fault tolerant control techniques for base isolation systems with magneto-rheological (MR) dampers. Thus, this paper presents a fixed-order FDI filter design procedure based on linear matrix inequalities (LMI). The necessary and sufficient conditions for the existence of a solution for detecting and isolating faults using the H ∞ formulation is provided in the proposed filter design. Furthermore, an FDI-filter-based fuzzy fault tolerant controller (FFTC) for a base isolation structure model was designed to preserve the pre-specified performance of the system in the presence of various unknown faults. Simulation and experimental results demonstrated that the designed filter can successfully detect and isolate faults from displacement sensors and accelerometers while maintaining excellent performance of the base isolation technology under faulty conditions

  1. A two-stage approach for managing actuators redundancy and its application to fault tolerant flight control

    Directory of Open Access Journals (Sweden)

    Zhong Lunlong

    2015-04-01

    Full Text Available In safety-critical systems such as transportation aircraft, redundancy of actuators is introduced to improve fault tolerance. How to make the best use of remaining actuators to allow the system to continue achieving a desired operation in the presence of some actuators failures is the main subject of this paper. Considering that many dynamical systems, including flight dynamics of a transportation aircraft, can be expressed as an input affine nonlinear system, a new state representation is adopted here where the output dynamics are related with virtual inputs associated with the intended operation. This representation, as well as the distribution matrix associated with the effectiveness of the remaining operational actuators, allows us to define different levels of fault tolerant governability with respect to actuators’ failures. Then, a two-stage control approach is developed, leading first to the inversion of the output dynamics to get nominal values for the virtual inputs and then to the solution of a linear quadratic (LQ problem to compute the solicitation of each operational actuator. The proposed approach is applied to the control of a transportation aircraft which performs a stabilized roll maneuver while a partial failure appears. Two fault scenarios are considered and the resulting performance of the proposed approach is displayed and discussed.

  2. The Radiation Tolerant Electronics for the LHC Cryogenic Controls: Basic Design and First Operational Experience

    CERN Document Server

    Casas-Cubillos, J; Rodríguez-Ruiz, M A

    2008-01-01

    The LHC optics is based in the extensive use of superconducting magnets covering 23 km inside the tunnel. The associated cryogenic system for keeping the magnets in nominal conditions is hence distributed all around the 27 km LHC tunnel and the cryogenic instrumentation submitted to the LHC radiation environment is composed of about 18’000 sensors and actuators. Radiation Tolerant (RadTol) electronics was designed and procured in order to keep the signals integrity against electromagnetic interference and to reduce cabling costs required in case of sending the analog signals into the 30 radiation protected areas. This paper presents the basic design, the qualification of the main RadTol components and the first operational results.

  3. Regulatory risk control through mandatory occupational safety and health (OSH) certification and testing regimes (CTRs)

    NARCIS (Netherlands)

    Zwetsloot, G.I.J.M.; Hale, A.; Zwanikken, S.

    2011-01-01

    Governments make increasing use of private certification and testing infrastructures as an alternative for traditional regulatory arrangements in several areas including occupational safety and health (OSH).This research, commissioned by the Dutch Inspectorate for Work and Income (IWI), concerns an

  4. Assisting IAEA Member States to Strengthen Regulatory Control, Particularly in the Medical Area

    International Nuclear Information System (INIS)

    Johnston, P.

    2016-01-01

    As per its Statue and Mandate, IAEA is developing Safety Standards and is also providing assistance for their application in Member States. One target and very large audience of this programme is the community of national regulatory bodies for radiation safety, expected to be established in all 168 Member States. Ionizing radiation is being used throughout the world in medical practices and medical exposure is the most significant manmade source of exposure to the population from ionizing radiation. Radiation accidents involving medical uses have accounted for more injuries and early acute health effects than any other type of radiation accident, including accidents at nuclear facilities. With the constant emerging of new technologies using ionizing radiation for medical diagnostic and treatment, there are on-going challenges for Regulatory bodies. The presentation will highlight some figures related to the medical exposure worldwide, and then it will introduce the main safety standards and other publications developed specifically for Regulatory Bodies and focusing on medical practices. It will also highlight the most important and recent mechanisms (tools, peer reviews and advisory services, training courses, networks) that the Agency is offering to its Member States in order to cope with the main challenges worldwide, contributing thus to the efficiency and effectiveness of the regulatory oversight of medical facilities and activities. (author)

  5. Regulatory control of solid low level radioactive waste disposal in the UK

    International Nuclear Information System (INIS)

    Newstead, S.; Schwemlein, P.

    1998-01-01

    The following topics are described: (i) regulatory authorities; (ii) inspection; (iii) waste categories; (iv) disposal routes for low level waste; (v) inspection of disposal routes; (vi) waste quality checking; (vii) reporting and application of results; and (viii) European Network activities. (P.A.)

  6. Maternal Depression, Locus of Control, and Emotion Regulatory Strategy as Predictors of Preschoolers' Internalizing Problems

    Science.gov (United States)

    Coyne, Lisa W.; Thompson, Alysha D.

    2011-01-01

    Childhood internalizing problems may occur as early as preschool, tend to be stable over time, and undermine social and academic functioning. Parent emotion regulatory behaviors may contribute to child internalizing problems and may be especially important during the preschool years when parents model emotion coping and regulation for their…

  7. Rate setting and regulatory control of the radionuclides content in foodstuffs

    International Nuclear Information System (INIS)

    Shandala, N. K.; Savskin, M. N.; Petukhova, E. V.; Novikova, N. Y.; Titov, A. V.

    2004-01-01

    The concept of rate setting, standardisation and regulatory control of the radionuclides content in foodstuffs consists in the following: ? the normative standards concern to 90Sr and 137Cs as biologically significant radionuclides; ? the internal exposure dose from ingestion intake of radionuclides with food should not exceed meaning of 1 mSv a-1 which is the intervention exception level concerning trading foodstuffs; ? for few consumed foodstuffs (wild berries, mushrooms, teas) is established, that the dose caused by their consumption is outside of dose limits of 1 mSv a-1 and it should not exceed 1 % for each product; ? the nutrition structure of population including seven basic components of a diet (bread and grain products, dairy products, potatoes, vegetables, meat, fish, fruit and berries) is taken into account as a source of ingestion intake of the radionuclides; ? The conformity to the established standard is determined on a parameter ?f the summary contents of 90Sr and 137Cs in foodstuff. With the purpose of the operative control of an internal exposure of population the permissible levels of specific activity of 90Sr and 137Cs in more than 120 kinds of foodstuff were developed. These standards are obligatory in Russia for domestic and imported foodstuffs. So, permissible levels of specific activity of 90Sr and 137Cs in bread make, accordingly, 20 and 40 Bq kg-1; in milk - 25 and 100 Bq kg-1; in meat - 50 and 160 Bq kg-1; in potatoes and vegetables - 40 and 120 Bq kg-1. Monitoring of contamination of foodstuffs by 137Cs and 90Sr is one of the basic measures on maintenance of radiation safety of population in Russia. State system of sanitary-epidemiological control carries out constant supervision over the content of the radionuclides in food production. By the carried out researches was shown that true levels of the contents of 90Sr or 137Cs in the main foodstuffs in territory of Russia, except for the territories, injures of the radiation accidents, make

  8. Long-term tolerability of inhaled human insulin (Exubera) in patients with poorly controlled type 2 diabetes

    DEFF Research Database (Denmark)

    Barnett, A H; Lange, P; Dreyer, M

    2007-01-01

    or metformin (study 1) and patients poorly controlled on metformin were randomised to adjunctive EXU or the sulphonylurea, glibenclamide (study 2). PATIENTS: The studies included 446 (study 1) and 476 (study 2) patients with type 2 diabetes, no clinically significant respiratory disease and glycosylated....... There was no discernable effect of long-term EXU therapy on pulmonary gas exchange. Insulin antibody binding reached a plateau at 6 months and did not correlate with HbA(1c) or lung function changes. Glycaemic control was maintained over 2 years. CONCLUSIONS: Exubera was well tolerated during long-term use. Pulmonary...... function changes compared with comparator groups were small, non-progressive and reversed upon treatment discontinuation. Importantly, rates of lung function change were indistinguishable between EXU and comparator after 6 months of therapy. Udgivelsesdato: 2007-Oct...

  9. USAGE OF STANDARD PERSONAL COMPUTER PORTS FOR DESIGNING OF THE DOUBLE REDUNDANT FAULT-TOLERANT COMPUTER CONTROL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Rafig SAMEDOV

    2005-01-01

    Full Text Available In this study, for designing of the fault-tolerant control systems by using standard personal computers, the ports have been investigated, different structure versions have been designed and the method for choosing of an optimal structure has been suggested. In this scope, first of all, the ÇİFTYAK system has been defined and its work principle has been determined. Then, data transmission ports of the standard personal computers have been classified and analyzed. After that, the structure versions have been designed and evaluated according to the used data transmission methods, the numbers of ports and the criterions of reliability, performance, truth, control and cost. Finally, the method for choosing of the most optimal structure version has been suggested.

  10. The catabolite repression control protein Crc plays a role in the development of antimicrobial-tolerant subpopulations in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Zhang, Lianbo; Chiang, Wen-Chi; Gao, Qingguo

    2012-01-01

    Bacteria form complex surface-attached biofilm communities in nature. Biofilm cells differentiate into subpopulations which display tolerance towards antimicrobial agents. However, the signal transduction pathways regulating subpopulation differentiation in biofilms are largely unelucidated. In t....... In the present study, we show that the catabolite repression control protein Crc regulates the metabolic state of Pseudomonas aeruginosa cells in biofilms, and plays an important role in the development of antimicrobial-tolerant subpopulations in P. aeruginosa biofilms....

  11. New CSA guideline for the exemption or clearance from regulatory control of materials that contain, or potentially contain, nuclear substances

    International Nuclear Information System (INIS)

    Rhodes, M.; Kwong, A.

    2011-01-01

    The Canadian Standards Association (CSA) guideline N292.5, Guideline for the exemption or clearance from regulatory control of materials that contain, or potentially contain, nuclear substances, was recently developed to address a need for guidance on approaches for clearance of materials from facilities licensed by the Canadian Nuclear Safety Commission (CNSC) consistent with Canadian and international recommendations. This guideline is also applicable to determining if an activity associated with materials that contain nuclear substances is exempt from requiring a CNSC licence. The guideline summarizes the regulatory requirements associated with the exemption and clearance of materials and provides a graded approach to designing a survey based on the risk of residual contamination being present. (author)

  12. Regulatory measures of BARC Safety Council to control radiation exposure in BARC Facilities

    International Nuclear Information System (INIS)

    Rajdeep; Jolly, V.M.; Jayarajan, K.

    2018-01-01

    Bhabha Atomic Research Centre is involved in multidisciplinary research and developmental activities, related to peaceful use of nuclear energy including societal benefits. BARC facilities at different parts of India include nuclear fuel fabrication facilities, research reactors, nuclear recycle facilities and various Physics, Chemistry and Biological laboratories. BARC Safety Council (BSC) is the regulatory body for BARC facilities and takes regulatory measures for radiation protection. BSC has many safety committees for radiation protection including Operating Plants Safety Review Committee (OPSRC), Committee to Review Applications for Authorization of Safe Disposal of Radioactive Wastes (CRAASDRW) and Design Safety Review Committees (DSRC) in 2 nd tier and Unit Level Safety Committees (ULSCs) in 3 rd tier under OPSRC

  13. Regulatory control of radiation sources and radioactive materials: The UK position

    International Nuclear Information System (INIS)

    Englefield, C.; Holyoak, B.; Ledgerwood, K.; Littlewood, K.

    2001-01-01

    The paper presents the organizations involved in the regulation of the safety of radiation sources and the security of radioactive materials across the UK. The safety of radiation sources is within the regulatory remit of the Health and Safety Executive, under the Health and safety of Work Act 1974 and associated regulations. Any employer using radiation sources has a statutory duty to comply with this legislation, thereby protecting workers and the public from undue risk. From a radioactive waste management perspective, the storage and use of radioactive materials and the accumulation and disposal of radioactive waste are regulated by the environment agencies of England and Wales, Scotland, and Northern Ireland, under the Radioactive Substances Act 1993. Special regulatory arrangements apply to nuclear sites, such as power stations and fuel cycle plants, and some additional bodies are involved in the regulation of the security of fissile materials. An explanation is given in the paper as to how these organizations to work together to provide a comprehensive and effective regulatory regime. An overview of how these regulators have recently started to work more closely with other enforcement bodies, such as the Police and Customs and Excise is also given, to illustrate the approach that is being applied in the UK to deal with orphan sources and illicit trafficking. (author)

  14. Event-triggered decentralized adaptive fault-tolerant control of uncertain interconnected nonlinear systems with actuator failures.

    Science.gov (United States)

    Choi, Yun Ho; Yoo, Sung Jin

    2018-06-01

    This paper investigates the event-triggered decentralized adaptive tracking problem of a class of uncertain interconnected nonlinear systems with unexpected actuator failures. It is assumed that local control signals are transmitted to local actuators with time-varying faults whenever predefined conditions for triggering events are satisfied. Compared with the existing control-input-based event-triggering strategy for adaptive control of uncertain nonlinear systems, the aim of this paper is to propose a tracking-error-based event-triggering strategy in the decentralized adaptive fault-tolerant tracking framework. The proposed approach can relax drastic changes in control inputs caused by actuator faults in the existing triggering strategy. The stability of the proposed event-triggering control system is analyzed in the Lyapunov sense. Finally, simulation comparisons of the proposed and existing approaches are provided to show the effectiveness of the proposed theoretical result in the presence of actuator faults. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Feedback Linearization approach for Standard and Fault Tolerant control: Application to a Quadrotor UAV Testbed

    International Nuclear Information System (INIS)

    Ghandour, J; Aberkane, S; Ponsart, J-C

    2014-01-01

    In this paper the control problem of a quadrotor vehicle experiencing a rotor failure is investigated. We develop a Feedback linearization approach to design a controller whose task is to make the vehicle performs trajectory following. Then we use the same approach to design a controller whose task is to make the vehicle enter a stable spin around its vertical axis, while retaining zero angular velocities around the other axis when a rotor failure is present. These conditions can be exploited to design a second control loop, which is used to perform trajectory following. The proposed double control loop architecture allows the vehicle to perform both trajectory and roll/pitch control. At last, to test the robustness of the feedback linearization technique, we applied wind to the quadrotor in mid flight

  16. Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

    OpenAIRE

    Williams, Wyatt I; Friedman, Jonathan M; Gaskin, John F; Norton, Andrew P

    2014-01-01

    Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgressi...

  17. Regulatory competence and social communication in term and preterm infants at 12 months corrected age. Results from a randomized controlled trial.

    Science.gov (United States)

    Olafsen, Kåre S; Rønning, John A; Handegård, Bjørn Helge; Ulvund, Stein Erik; Dahl, Lauritz Bredrup; Kaaresen, Per Ivar

    2012-02-01

    Temperamental regulatory competence and social communication in term and preterm infants at 12 months corrected age was studied in a randomized controlled intervention trial aimed at enhancing maternal sensitive responsiveness. Surviving infants communication with the Early Social Communication Scales. Preterm intervention infants with low regulatory competence had higher responding to joint attention than preterm control infants. A sensitizing intervention may moderate the association between temperament and social communication, and thus allow an alternative functional outlet for preterm infants low in regulatory competence. The finding may have implications for conceptualizations of the role of early sensitizing interventions in promoting important developmental outcomes for premature infants. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. RelB+ Steady-State Migratory Dendritic Cells Control the Peripheral Pool of the Natural Foxp3+ Regulatory T Cells

    Directory of Open Access Journals (Sweden)

    Anja Döhler

    2017-06-01

    Full Text Available Thymus-derived natural Foxp3+ CD4+ regulatory T cells (nTregs play a key role in maintaining immune tolerance and preventing autoimmune disease. Several studies indicate that dendritic cells (DCs are critically involved in the maintenance and proliferation of nTregs. However, the mechanisms how DCs manage to keep the peripheral pool at constant levels remain poorly understood. Here, we describe that the NF-κB/Rel family transcription factor RelB controls the frequencies of steady-state migratory DCs (ssmDCs in peripheral lymph nodes and their numbers control peripheral nTreg homeostasis. DC-specific RelB depletion was investigated in CD11c-Cre × RelBfl/fl mice (RelBDCko, which showed normal frequencies of resident DCs in lymph nodes and spleen while the subsets of CD103− Langerin− dermal DCs (dDCs and Langerhans cells but not CD103+ Langerin+ dDC of the ssmDCs in skin-draining lymph nodes were increased. Enhanced frequencies and proliferation rates were also observed for nTregs and a small population of CD4+ CD44high CD25low memory-like T cells (Tml. Interestingly, only the Tml but not DCs showed an increase in IL-2-producing capacity in lymph nodes of RelBDCko mice. Blocking of IL-2 in vivo reduced the frequency of nTregs but increased the Tml frequencies, followed by a recovery of nTregs. Taken together, by employing RelBDCko mice with increased frequencies of ssmDCs our data indicate a critical role for specific ssmDC subsets for the peripheral nTreg and IL-2+ Tml frequencies during homeostasis.

  19. CD28-CD80 interactions control regulatory T cell motility and immunological synapse formation1,2

    Science.gov (United States)

    Thauland, Timothy J.; Koguchi, Yoshinobu; Dustin, Michael L.; Parker, David C.

    2014-01-01

    Regulatory T cells (Tregs) are essential for tolerance to self and environmental antigens, acting in part by downmodulating costimulatory molecules on the surface of dendritic cells (DCs) and altering naïve CD4 T cell-DC interactions. Here, we show that Tregs form stable conjugates with DCs before, but not after, they decrease surface expression of the costimulatory molecule CD80 on the DCs. We use supported planar bilayers to show that Tregs dramatically slow down, but maintain a highly polarized and motile phenotype after recognizing antigen in the absence of costimulation. These motile cells are characterized by distinct accumulations of LFA-1-ICAM-1 in the lamella and TCR-MHC in the uropod, consistent with a motile immunological synapse or ‘kinapse’. However, in the presence of high, but not low, concentrations of CD80, Tregs form stationary, symmetrical synapses. Using blocking antibodies, we show that, while CTLA-4 is required for CD80 downmodulation, CD28-CD80 interactions are critical for modulating Treg motility in the presence of antigen. Together, these results support the hypothesis that Tregs are tuned to alter their motility depending on costimulatory signals. PMID:25355918

  20. Radiation Tolerance of Controlled Fusion Welds in High Temperature Oxidation Resistant FeCrAl Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gussev, Maxim N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Field, Kevin G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    High temperature oxidation resistant iron-chromium-aluminum (FeCrAl) alloys are candidate alloys for nuclear applications due to their exceptional performance during off-normal conditions such as a loss-of-coolant accident (LOCA) compared to currently deployed zirconium-based claddings [1]. A series of studies have been completed to determine the weldability of the FeCrAl alloy class and investigate the weldment performance in the as-received (non-irradiated) state [2,3]. These initial studies have shown the general effects of composition and microstructure on the weldability of FeCrAl alloys. Given this, limited details on the radiation tolerance of FeCrAl alloys and their weldments exist. Here, the highest priority candidate FeCrAl alloys and their weldments have been investigated after irradiation to enable a better understanding of FeCrAl alloy weldment performance within a high-intensity neutron field. The alloys examined include C35M (Fe-13%Cr-5% Al) and variants with aluminum (+2%) or titanium carbide (+1%) additions. Two different sub-sized tensile geometries, SS-J type and SS-2E (or SS-mini), were neutron irradiated in the High Flux Isotope Reactor to 1.8-1.9 displacements per atom (dpa) in the temperature range of 195°C to 559°C. Post irradiation examination of the candidate alloys was completed and included uniaxial tensile tests coupled with digital image correlation (DIC), scanning electron microscopy-electron back scattered diffraction analysis (SEM-EBSD), and SEM-based fractography. In addition to weldment testing, non-welded parent material was examined as a direct comparison between welded and non-welded specimen performance. Both welded and non-welded specimens showed a high degree of radiation-induced hardening near irradiation temperatures of 200°C, moderate radiation-induced hardening near temperatures of 360°C, and almost no radiation-induced hardening at elevated temperatures near 550°C. Additionally, low-temperature irradiations showed

  1. Transient Tolerant Automated Control System for the LEDA 75kV Injector

    International Nuclear Information System (INIS)

    Thuot, M.E.; Dalesio, L.R.; Harrington, M.; Hodgkins, D.; Kerstiens, D.M.; Stettler, M.W.; Warren, D.S.; Zaugg, T.; Arvin, A.; Bolt, S.; Richards, M.

    1999-01-01

    The Low-Energy Demonstration Accelerator (LEDA) injector is designed to inject 75-keV, 110-mA, proton beams into the LEDA RFQ. The injector operation has been automated to provide long term, high availability operation using the Experimental Physics and Industrial Control System (EPICS). Automated recovery from spark-downs demands reliable spark detection and sequence execution by the injector controller. Reliable computer control in the high-energy transient environment required transient suppression and isolation of hundreds of analog and binary data lines connecting the EPICS computer controller to the injector and it's power supplies and diagnostics. A transient suppression design based on measured and modeled spark transient parameters provides robust injector operation. This paper describes the control system hardware and software design, implementation and operational performance

  2. Characterization of a putative cis-regulatory element that controls transcriptional activity of the pig uroplakin II gene promoter

    International Nuclear Information System (INIS)

    Kwon, Deug-Nam; Park, Mi-Ryung; Park, Jong-Yi; Cho, Ssang-Goo; Park, Chankyu; Oh, Jae-Wook; Song, Hyuk; Kim, Jae-Hwan; Kim, Jin-Hoi

    2011-01-01

    Highlights: → The sequences of -604 to -84 bp of the pUPII promoter contained the region of a putative negative cis-regulatory element. → The core promoter was located in the 5F-1. → Transcription factor HNF4 can directly bind in the pUPII core promoter region, which plays a critical role in controlling promoter activity. → These features of the pUPII promoter are fundamental to development of a target-specific vector. -- Abstract: Uroplakin II (UPII) is a one of the integral membrane proteins synthesized as a major differentiation product of mammalian urothelium. UPII gene expression is bladder specific and differentiation dependent, but little is known about its transcription response elements and molecular mechanism. To identify the cis-regulatory elements in the pig UPII (pUPII) gene promoter region, we constructed pUPII 5' upstream region deletion mutants and demonstrated that each of the deletion mutants participates in controlling the expression of the pUPII gene in human bladder carcinoma RT4 cells. We also identified a new core promoter region and putative negative cis-regulatory element within a minimal promoter region. In addition, we showed that hepatocyte nuclear factor 4 (HNF4) can directly bind in the pUPII core promoter (5F-1) region, which plays a critical role in controlling promoter activity. Transient cotransfection experiments showed that HNF4 positively regulates pUPII gene promoter activity. Thus, the binding element and its binding protein, HNF4 transcription factor, may be involved in the mechanism that specifically regulates pUPII gene transcription.

  3. Observer-based distributed adaptive fault-tolerant containment control of multi-agent systems with general linear dynamics.

    Science.gov (United States)

    Ye, Dan; Chen, Mengmeng; Li, Kui

    2017-11-01

    In this paper, we consider the distributed containment control problem of multi-agent systems with actuator bias faults based on observer method. The objective is to drive the followers into the convex hull spanned by the dynamic leaders, where the input is unknown but bounded. By constructing an observer to estimate the states and bias faults, an effective distributed adaptive fault-tolerant controller is developed. Different from the traditional method, an auxiliary controller gain is designed to deal with the unknown inputs and bias faults together. Moreover, the coupling gain can be adjusted online through the adaptive mechanism without using the global information. Furthermore, the proposed control protocol can guarantee that all the signals of the closed-loop systems are bounded and all the followers converge to the convex hull with bounded residual errors formed by the dynamic leaders. Finally, a decoupled linearized longitudinal motion model of the F-18 aircraft is used to demonstrate the effectiveness. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Short-Circuit Fault Tolerant Control of a Wind Turbine Driven Induction Generator Based on Sliding Mode Observers

    Directory of Open Access Journals (Sweden)

    Takwa Sellami

    2017-10-01

    Full Text Available The installed energy production capacity of wind turbines is growing intensely on a global scale, making the reliability of wind turbine subsystems of greater significance. However, many faults like Inter-Turn Short-Circuit (ITSC may affect the turbine generator and quickly lead to a decline in supplied power quality. In this framework, this paper proposes a Sliding Mode Observer (SMO-based Fault Tolerant Control (FTC scheme for Induction Generator (IG-based variable-speed grid-connected wind turbines. First, the dynamic models of the wind turbine subsystems were developed. The control schemes were elaborated based on the Maximum Power Point Tracking (MPPT method and Indirect Rotor Flux Oriented Control (IRFOC method. The grid control was also established by regulating the active and reactive powers. The performance of the wind turbine system and the stability of injected power to the grid were hence analyzed under both healthy and faulty conditions. The robust developed SMO-based Fault Detection and Isolation (FDI scheme was proved to be fast and efficient for ITSC detection and localization.Afterwards, SMO were involved in scheming the FTC technique. Accordingly, simulation results assert the efficacy of the proposed ITSC FTC method for variable-speed wind turbines with faulty IG in protecting the subsystems from damage and ensuring continuous connection of the wind turbine to the grid during ITSC faults, hence maintaining power quality.

  5. Adaptive Fault-Tolerant Synchronization Control of a Class of Complex Dynamical Networks With General Input Distribution Matrices and Actuator Faults.

    Science.gov (United States)

    Li, Xiao-Jian; Yang, Guang-Hong

    2017-03-01

    This paper is concerned with the problem of adaptive fault-tolerant synchronization control of a class of complex dynamical networks (CDNs) with actuator faults and unknown coupling weights. The considered input distribution matrix is assumed to be an arbitrary matrix, instead of a unit one. Within this framework, an adaptive fault-tolerant controller is designed to achieve synchronization for the CDN. Moreover, a convex combination technique and an important graph theory result are developed, such that the rigorous convergence analysis of synchronization errors can be conducted. In particular, it is shown that the proposed fault-tolerant synchronization control approach is valid for the CDN with both time-invariant and time-varying coupling weights. Finally, two simulation examples are provided to validate the effectiveness of the theoretical results.

  6. Genetic horoscopes: is it all in the genes? Points for regulatory control of direct-to-consumer genetic testing.

    Science.gov (United States)

    Patch, Christine; Sequeiros, Jorge; Cornel, Martina C

    2009-07-01

    The development of tests for genetic susceptibility to common complex diseases has raised concerns. These concerns relate to evaluation of the scientific and clinical validity and utility of the tests, quality assurance of laboratories and testing services, advice and protection for the consumer and the appropriate regulatory and policy response. How these concerns are interpreted and addressed is an ongoing debate. If the possibility of using the discoveries from genomic science to improve health is to be realised without losing public confidence, then improvements in the evaluation and mechanisms for control of supply of tests may be as important as the science itself.

  7. System-Level Development of Fault-Tolerant Distributed Aero-Engine Control Architecture, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's vision for an "intelligent engine" will be realized with the development of a truly distributed control system and reliable smart transducer node components;...

  8. Characterization of regulatory pathways in Xylella fastidiosa: genes and phenotypes controlled by algU.

    Science.gov (United States)

    Shi, Xiang Yang; Dumenyo, C Korsi; Hernandez-Martinez, Rufina; Azad, Hamid; Cooksey, Donald A

    2007-11-01

    Many virulence genes in plant bacterial pathogens are coordinately regulated by "global" regulatory genes. Conducting DNA microarray analysis of bacterial mutants of such genes, compared with the wild type, can help to refine the list of genes that may contribute to virulence in bacterial pathogens. The regulatory gene algU, with roles in stress response and regulation of the biosynthesis of the exopolysaccharide alginate in Pseudomonas aeruginosa and many other bacteria, has been extensively studied. The role of algU in Xylella fastidiosa, the cause of Pierce's disease of grapevines, was analyzed by mutation and whole-genome microarray analysis to define its involvement in aggregation, biofilm formation, and virulence. In this study, an algU::nptII mutant had reduced cell-cell aggregation, attachment, and biofilm formation and lower virulence in grapevines. Microarray analysis showed that 42 genes had significantly lower expression in the algU::nptII mutant than in the wild type. Among these are several genes that could contribute to cell aggregation and biofilm formation, as well as other physiological processes such as virulence, competition, and survival.

  9. Foxp3+ regulatory T cells control persistence of viral CNS infection.

    Directory of Open Access Journals (Sweden)

    Dajana Reuter

    Full Text Available We earlier established a model of a persistent viral CNS infection using two week old immunologically normal (genetically unmodified mice and recombinant measles virus (MV. Using this model infection we investigated the role of regulatory T cells (Tregs as regulators of the immune response in the brain, and assessed whether the persistent CNS infection can be modulated by manipulation of Tregs in the periphery. CD4(+ CD25(+ Foxp3(+ Tregs were expanded or depleted during the persistent phase of the CNS infection, and the consequences for the virus-specific immune response and the extent of persistent infection were analyzed. Virus-specific CD8(+ T cells predominantly recognising the H-2D(b-presented viral hemagglutinin epitope MV-H(22-30 (RIVINREHL were quantified in the brain by pentamer staining. Expansion of Tregs after intraperitoneal (i.p. application of the superagonistic anti-CD28 antibody D665 inducing transient immunosuppression caused increased virus replication and spread in the CNS. In contrast, depletion of Tregs using diphtheria toxin (DT in DEREG (depletion of regulatory T cells-mice induced an increase of virus-specific CD8(+ effector T cells in the brain and caused a reduction of the persistent infection. These data indicate that manipulation of Tregs in the periphery can be utilized to regulate virus persistence in the CNS.

  10. Event-Triggered Faults Tolerant Control for Stochastic Systems with Time Delays

    Directory of Open Access Journals (Sweden)

    Ling Huang

    2016-01-01

    Full Text Available This paper is concerned with the state-feedback controller design for stochastic networked control systems (NCSs with random actuator failures and transmission delays. Firstly, an event-triggered scheme is introduced to optimize the performance of the stochastic NCSs. Secondly, stochastic NCSs under event-triggered scheme are modeled as stochastic time-delay systems. Thirdly, some less conservative delay-dependent stability criteria in terms of linear matrix inequalities for the codesign of both the controller gain and the trigger parameters are obtained by using delay-decomposition technique and convex combination approach. Finally, a numerical example is provided to show the less sampled data transmission and less conservatism of the proposed theory.

  11. An Active Fault-Tolerant Control Method Ofunmanned Underwater Vehicles with Continuous and Uncertain Faults

    Directory of Open Access Journals (Sweden)

    Daqi Zhu

    2008-11-01

    Full Text Available This paper introduces a novel thruster fault diagnosis and accommodation system for open-frame underwater vehicles with abrupt faults. The proposed system consists of two subsystems: a fault diagnosis subsystem and a fault accommodation sub-system. In the fault diagnosis subsystem a ICMAC(Improved Credit Assignment Cerebellar Model Articulation Controllers neural network is used to realize the on-line fault identification and the weighting matrix computation. The fault accommodation subsystem uses a control algorithm based on weighted pseudo-inverse to find the solution of the control allocation problem. To illustrate the proposed method effective, simulation example, under multi-uncertain abrupt faults, is given in the paper.

  12. Design of LPV fault-tolerant controller for pitch system of wind turbine

    Science.gov (United States)

    Wu, Dinghui; Zhang, Xiaolin

    2017-07-01

    To address failures of wind turbine pitch-angle sensors, traditional wind turbine linear parameter varying (LPV) model is transformed into a double-layer convex polyhedron LPV model. On the basis of this model, when the plurality of the sensor undergoes failure and details of the failure are inconvenient to obtain, each sub-controller is designed using distributed thought and gain scheduling method. The final controller is obtained using all of the sub-controllers by a convex combination. The design method corrects the errors of the linear model, improves the linear degree of the system, and solves the problem of multiple pitch angle faults to ensure stable operation of the wind turbine.

  13. Creating a Comprehensive, Efficient, and Sustainable Nuclear Regulatory Structure: A Process Report from the U.S. Department of Energy's Material Protection, Control and Accounting Program

    International Nuclear Information System (INIS)

    Wright, Troy L.; O'Brien, Patricia E.; Hazel, Michael J.; Tuttle, John D.; Cunningham, Mitchel E.; Schlegel, Steven C.

    2010-01-01

    With the congressionally mandated January 1, 2013 deadline for the U.S. Department of Energy's (DOE) Nuclear Material Protection, Control and Accounting (MPC and A) program to complete its transition of MPC and A responsibility to the Russian Federation, National Nuclear Security Administration (NNSA) management directed its MPC and A program managers and team leaders to demonstrate that work in ongoing programs would lead to successful and timely achievement of these milestones. In the spirit of planning for successful project completion, the NNSA review of the Russian regulatory development process confirmed the critical importance of an effective regulatory system to a sustainable nuclear protection regime and called for an analysis of the existing Russian regulatory structure and the identification of a plan to ensure a complete MPC and A regulatory foundation. This paper describes the systematic process used by DOE's MPC and A Regulatory Development Project (RDP) to develop an effective and sustainable MPC and A regulatory structure in the Russian Federation. This nuclear regulatory system will address all non-military Category I and II nuclear materials at State Corporation for Atomic Energy 'Rosatom,' the Federal Service for Ecological, Technological, and Nuclear Oversight (Rostechnadzor), the Federal Agency for Marine and River Transport (FAMRT, within the Ministry of Transportation), and the Ministry of Industry and Trade (Minpromtorg). The approach to ensuring a complete and comprehensive nuclear regulatory structure includes five sequential steps. The approach was adopted from DOE's project management guidelines and was adapted to the regulatory development task by the RDP. The five steps in the Regulatory Development Process are: (1) Define MPC and A Structural Elements; (2) Analyze the existing regulatory documents using the identified Structural Elements; (3) Validate the analysis with Russian colleagues and define the list of documents to be

  14. Review of fault diagnosis and fault-tolerant control for modular multilevel converter of HVDC

    DEFF Research Database (Denmark)

    Liu, Hui; Loh, Poh Chiang; Blaabjerg, Frede

    2013-01-01

    This review focuses on faults in Modular Multilevel Converter (MMC) for use in high voltage direct current (HVDC) systems by analyzing the vulnerable spots and failure mechanism from device to system and illustrating the control & protection methods under failure condition. At the beginning......, several typical topologies of MMC-HVDC systems are presented. Then fault types such as capacitor voltage unbalance, unbalance between upper and lower arm voltage are analyzed and the corresponding fault detection and diagnosis approaches are explained. In addition, more attention is dedicated to control...

  15. An fMRI Study of Self-Regulatory Control and Conflict Resolution in Adolescents With Bulimia Nervosa

    Science.gov (United States)

    Marsh, Rachel; Horga, Guillermo; Wang, Zhishun; Wang, Pengwei; Klahr, Kristin W.; Berner, Laura A.; Walsh, B. Timothy; Peterson, Bradley S.

    2012-01-01

    Objective The authors examined functional activity in the frontostriatal systems that mediate self-regulatory capacities and conflict resolution in adolescents with bulimia nervosa. Method Functional magnetic resonance imaging was used to compare blood-oxygen-level-dependent response in 18 female adolescents with bulimia nervosa and 18 healthy female age-matched subjects during performance on a Simon spatial incompatibility task. Bayesian analyses were used to compare the two groups on patterns of brain activation during correct responses to conflict stimuli and to explore the effects of antecedent stimulus context on group differences in self-regulation and conflict resolution. Results Adolescents with and without bulimia nervosa performed similarly on the task. During correct responses in conflict trials, frontostriatal circuits—including the right inferolateral and dorsolateral prefrontal cortices and putamen—failed to activate to the same degree in adolescents with bulimia nervosa as in healthy comparison subjects. Instead, deactivation was seen in the left inferior frontal gyrus as well as a neural system encompassing the posterior cingulate cortex and superior frontal gyrus. Group differences in cortical and striatal regions were driven by the differential responses to stimuli preceded by conflict and nonconflict stimuli, respectively. Conclusions When engaging the self-regulatory control processes necessary to resolve conflict, adolescents with bulimia nervosa displayed abnormal patterns of activation in frontostriatal and default-mode systems. Their abnormal processing of the antecedent stimulus context conditioned their brain response to conflict differently from that of healthy comparison subjects, specifically in frontal regions. It is suspected that functional disturbances in frontal portions of frontostriatal systems may release feeding behaviors from regulatory control, thereby perpetuating the conflicting desires to consume fattening foods and

  16. Power maximization of variable-speed variable-pitch wind turbines using passive adaptive neural fault tolerant control

    Science.gov (United States)

    Habibi, Hamed; Rahimi Nohooji, Hamed; Howard, Ian

    2017-09-01

    Power maximization has always been a practical consideration in wind turbines. The question of how to address optimal power capture, especially when the system dynamics are nonlinear and the actuators are subject to unknown faults, is significant. This paper studies the control methodology for variable-speed variable-pitch wind turbines including the effects of uncertain nonlinear dynamics, system fault uncertainties, and unknown external disturbances. The nonlinear model of the wind turbine is presented, and the problem of maximizing extracted energy is formulated by designing the optimal desired states. With the known system, a model-based nonlinear controller is designed; then, to handle uncertainties, the unknown nonlinearities of the wind turbine are estimated by utilizing radial basis function neural networks. The adaptive neural fault tolerant control is designed passively to be robust on model uncertainties, disturbances including wind speed and model noises, and completely unknown actuator faults including generator torque and pitch actuator torque. The Lyapunov direct method is employed to prove that the closed-loop system is uniformly bounded. Simulation studies are performed to verify the effectiveness of the proposed method.

  17. Distributed sensor and actuator reconfiguration for fault-tolerant networked control systems

    NARCIS (Netherlands)

    Herdeiro Teixeira, A.M.; Araujo, Jose; Sandberg, Henrik; Johansson, Karl H.

    2017-01-01

    In this paper, we address the problem of distributed reconfiguration of networked control systems upon the removal of misbehaving sensors and actuators. In particular, we consider systems with redundant sensors and actuators cooperating to recover from faults. Reconfiguration is performed while

  18. Controlling herbicide-susceptible, -tolerant and -resistant weeds with microbial bioherbicides

    Science.gov (United States)

    The management of weeds is a necessary but expensive challenge. Public concerns of health, safety, and sustainability have increased interest in reducing the use of synthetic chemicals for weed control. Alternatives to chemical herbicides, such as bioherbicides, may offer an alternative to herbicide...

  19. Design methodology for fault-tolerant control of advanced driver assistance systems

    NARCIS (Netherlands)

    Gietelink, O.J.; Ploeg, J.; Schutter, B. de; Verhaegen, M.H.G.

    2003-01-01

    The objective of this project is to develop a methodology for the design, testing, evaluation and implementation of control systems for Advanced Driver Assistance Systems (ADAS). Examples of ADAS are collision avoidance systems, lane departure warning systems, pre-crash sensing, and adaptive cruise

  20. Robust and Fault-Tolerant Linear Parameter-Varying Control of Wind Turbines

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Esbensen, Thomas; Stoustrup, Jakob

    2011-01-01

    High performance and reliability are required for wind turbines to be competitive within the energy market. To capture their nonlinear behavior, wind turbines are often modeled using parameter-varying models. In this paper we design and compare multiple linear parameter-varying (LPV) controllers,...