Science.gov

Sample records for adaptive approach iaa

  1. Matched filter based iterative adaptive approach

    NASA Astrophysics Data System (ADS)

    Nepal, Ramesh; Zhang, Yan Rockee; Li, Zhengzheng; Blake, William

    2016-05-01

    Matched Filter sidelobes from diversified LPI waveform design and sensor resolution are two important considerations in radars and active sensors in general. Matched Filter sidelobes can potentially mask weaker targets, and low sensor resolution not only causes a high margin of error but also limits sensing in target-rich environment/ sector. The improvement in those factors, in part, concern with the transmitted waveform and consequently pulse compression techniques. An adaptive pulse compression algorithm is hence desired that can mitigate the aforementioned limitations. A new Matched Filter based Iterative Adaptive Approach, MF-IAA, as an extension to traditional Iterative Adaptive Approach, IAA, has been developed. MF-IAA takes its input as the Matched Filter output. The motivation here is to facilitate implementation of Iterative Adaptive Approach without disrupting the processing chain of traditional Matched Filter. Similar to IAA, MF-IAA is a user parameter free, iterative, weighted least square based spectral identification algorithm. This work focuses on the implementation of MF-IAA. The feasibility of MF-IAA is studied using a realistic airborne radar simulator as well as actual measured airborne radar data. The performance of MF-IAA is measured with different test waveforms, and different Signal-to-Noise (SNR) levels. In addition, Range-Doppler super-resolution using MF-IAA is investigated. Sidelobe reduction as well as super-resolution enhancement is validated. The robustness of MF-IAA with respect to different LPI waveforms and SNR levels is also demonstrated.

  2. ANALYSIS OF RADIAL VELOCITY DATA BY A NOVEL ADAPTIVE APPROACH

    SciTech Connect

    Babu, P.; Stoica, P.; Li, J.; Chen, Z.; Ge, J.

    2010-02-15

    In this paper, we introduce an estimation technique for analyzing radial velocity data commonly encountered in extrasolar planet detection. We discuss the Keplerian model for radial velocity data measurements and introduce a technique named the iterative adaptive approach (IAA) to estimate the three-dimensional spectrum (power versus eccentricity, orbital period and periastron passage time) of the radial velocity data. We then discuss different ways to regularize the IAA algorithm in the presence of noise and measurement errors. We also discuss briefly the computational aspects of the method and introduce a computationally efficient version of IAA. Finally, we establish the significance of the spectral peaks by using a relaxation maximum likelihood algorithm and a generalized likelihood ratio test. Numerical experiments are carried out on both simulated and real life data sets to evaluate the performance of our method. The real life data sets discussed are radial velocity measurements of the stars HD 63454, HD 208487, and GJ 876.

  3. Identification of IAA transport inhibitors including compounds affecting cellular PIN trafficking by two chemical screening approaches using maize coleoptile systems.

    PubMed

    Nishimura, Takeshi; Matano, Naoyuki; Morishima, Taichi; Kakinuma, Chieko; Hayashi, Ken-Ichiro; Komano, Teruya; Kubo, Minoru; Hasebe, Mitsuyasu; Kasahara, Hiroyuki; Kamiya, Yuji; Koshiba, Tomokazu

    2012-10-01

    The monocot coleoptile tip region has been generally supposed to be the source of IAA to supply IAA to basal parts by the polar IAA transport system, which results in gravi- and phototropic curvature of coleoptiles. Based on this IAA transport system and gravitropism of maize coleoptiles, we have developed two screening methods to identify small molecules from a large chemical library that inhibit IAA transport. The methods detect molecules that affect (i) gravitropic curvature of coleoptiles; and (ii) the amount of IAA transported from the tip. From 10,000 chemicals, eight compounds were identified and categorized into two groups. Four chemicals in group A decreased IAA transport from the tip, and increased endogenous IAA levels in the tip. The structures of two compounds resembled that of 1-N-naphthylphthalamic acid (NPA), but those of the other two differed from structures of known IAA transport inhibitors. Four chemicals in group B strongly inhibited IAA transport from the tip, but IAA levels at the tip were only slightly affected. At higher concentrations, group B compounds inhibited germination of Arabidopsis, similarly to brefeldin A (BFA). Analysis of the cellular distribution of PIN2-green fluorescent protein (GFP) and PIN1-GFP in Arabidopsis revealed that one of the four chemicals in group B induced internalization of PIN1 and PIN2 proteins into vesicles smaller than BFA bodies, suggesting that this compound affects cellular vesicle trafficking systems related to PIN trafficking. The eight chemicals identified here will be a useful tool for understanding the mechanisms of IAA transport in plants. PMID:22875609

  4. Efficient pulse compression for LPI waveforms based on a nonparametric iterative adaptive approach

    NASA Astrophysics Data System (ADS)

    Li, Zhengzheng; Nepal, Ramesh; Zhang, Yan; Blake, WIlliam

    2015-05-01

    In order to achieve low probability-of-intercept (LPI), radar waveforms are usually long and randomly generated. Due to the randomized nature, Matched filter responses (autocorrelation) of those waveforms can have high sidelobes which would mask weaker targets near a strong target, limiting radar's ability to distinguish close-by targets. To improve resolution and reduced sidelobe contaminations, a waveform independent pulse compression filter is desired. Furthermore, the pulse compression filter needs to be able to adapt to received signal to achieve optimized performance. As many existing pulse techniques require intensive computation, real-time implementation is infeasible. This paper introduces a new adaptive pulse compression technique for LPI waveforms that is based on a nonparametric iterative adaptive approach (IAA). Due to the nonparametric nature, no parameter tuning is required for different waveforms. IAA can achieve super-resolution and sidelobe suppression in both range and Doppler domains. Also it can be extended to directly handle the matched filter (MF) output (called MF-IAA), which further reduces the computational load. The practical impact of LPI waveform operations on IAA and MF-IAA has not been carefully studied in previous work. Herein the typical LPI waveforms such as random phase coding and other non- PI waveforms are tested with both single-pulse and multi-pulse IAA processing. A realistic airborne radar simulator as well as actual measured radar data are used for the validations. It is validated that in spite of noticeable difference with different test waveforms, the IAA algorithms and its improvement can effectively achieve range-Doppler super-resolution in realistic data.

  5. IAA Correlator Center

    NASA Technical Reports Server (NTRS)

    Surkis, Igor; Ken, Voitsekh; Melnikov, Alexey; Mishin, Vladimir; Sokolova, Nadezda; Shantyr, Violet; Zimovsky, Vladimir

    2013-01-01

    The activities of the six-station IAA RAS correlator include regular processing of national geodetic VLBI programs Ru-E, Ru-U, and Ru-F. The Ru-U sessions have been transferred in e-VLBI mode and correlated in the IAA Correlator Center automatically since 2011. The DiFX software correlator is used at the IAA in some astrophysical experiments.

  6. Space traffic management: The new comprehensive approach for regulating the use of outer space—Results from the 2006 IAA cosmic study

    NASA Astrophysics Data System (ADS)

    Schrogl, Kai-Uwe

    2008-01-01

    October 2007 held two anniversaries: 50 years ago, Sputnik was launched and 40 years ago, the Outer Space Treaty entered into force. The first satellite and the foundation of the legal regime governing outer space mark the two decisive points for the use of outer space and its international regulation. During the past decades, space activities have taken a tremendous development in quantity and scope. Regulation has, however, not been able to keep pace with technology, so that today the legal environment shows more and more shortcomings. This paper argues that the growing problems of space law cannot be solved by "piecemeal engineering" any more but can only be overcome through a "big bang" comprehensive approach for regulating space activities: Space traffic management (STM). The debate on this issue has recently been strongly invigorated by the publication of the IAA Cosmic Study on STM. [IAA "Cosmic Study on Space Traffic Management", Paris 2006, in: edited by C. Contant-Jorgensen (Secretary of the Study Group), P. Lala, K.-U. Schrogl (Coordinators of the Study Group) (Eds.), The Study Group consisted of 16 contributors from numerous countries covering engineering, policy and legal aspects. Download at iaa/Studies/spacetraffic.pdf>[1].

  7. The Limits to Adaptation; A Systems Approach

    EPA Science Inventory

    The Limits to Adaptation: A Systems Approach. The ability to adapt to climate change is delineated by capacity thresholds, after which climate damages begin to overwhelm the adaptation response. Such thresholds depend upon physical properties (natural processes and engineering...

  8. Understanding the adaptive approach to thermal comfort

    SciTech Connect

    Humphreys, M.A.; Nicol, J.F.

    1998-10-01

    This paper explains the adaptive approach to thermal comfort, and an adaptive model for thermal comfort is presented. The model is an example of a complex adaptive system (Casti 1996) whose equilibria are determined by the restrictions acting upon it. People`s adaptive actions are generally effective in securing comfort, which occurs at a wide variety of indoor temperatures. These comfort temperatures depend upon the circumstances in which people live, such as the climate and the heating or cooling regime. The temperatures may be estimated from the mean outdoor temperature and the availability of a heating or cooling plant. The evaluation of the parameters of the adaptive model requires cross-sectional surveys to establish current norms and sequential surveys (with and without intervention) to evaluate the rapidity of people`s adaptive actions. Standards for thermal comfort will need revision in the light of the adaptive approach. Implications of the adaptive model for the HVAC industry are noted.

  9. An adaptive signal-processing approach to online adaptive tutoring.

    PubMed

    Bergeron, Bryan; Cline, Andrew

    2011-01-01

    Conventional intelligent or adaptive tutoring online systems rely on domain-specific models of learner behavior based on rules, deep domain knowledge, and other resource-intensive methods. We have developed and studied a domain-independent methodology of adaptive tutoring based on domain-independent signal-processing approaches that obviate the need for the construction of explicit expert and student models. A key advantage of our method over conventional approaches is a lower barrier to entry for educators who want to develop adaptive online learning materials.

  10. Acquiring case adaptation knowledge: A hybrid approach

    SciTech Connect

    Leake, D.B.; Kinley, A.; Wilson, D.

    1996-12-31

    The ability of case-based reasoning (CBR) systems to apply cases to novel situations depends on their case adaptation knowledge. However, endowing CBR systems with adequate adaptation knowledge has proven to be a very difficult task. This paper describes a hybrid method for performing case adaptation, using a combination of rule-based and case-based reasoning. It shows how this approach provides a framework for acquiring flexible adaptation knowledge from experiences with autonomous adaptation and suggests its potential as a basis for acquisition of adaptation knowledge from interactive user guidance. It also presents initial experimental results examining the benefits of the approach and comparing the relative contributions of case learning and adaptation learning to reasoning performance.

  11. Flight Test Approach to Adaptive Control Research

    NASA Technical Reports Server (NTRS)

    Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

    2011-01-01

    The National Aeronautics and Space Administration s Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The validation of adaptive controls has the potential to enhance safety in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

  12. A Predictive Analysis Approach to Adaptive Testing.

    ERIC Educational Resources Information Center

    Kirisci, Levent; Hsu, Tse-Chi

    The predictive analysis approach to adaptive testing originated in the idea of statistical predictive analysis suggested by J. Aitchison and I.R. Dunsmore (1975). The adaptive testing model proposed is based on parameter-free predictive distribution. Aitchison and Dunsmore define statistical prediction analysis as the use of data obtained from an…

  13. The virtual machine (VM) scaler: an infrastructure manager supporting environmental modeling on IaaS clouds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infrastructure-as-a-service (IaaS) clouds provide a new medium for deployment of environmental modeling applications. Harnessing advancements in virtualization, IaaS clouds can provide dynamic scalable infrastructure to better support scientific modeling computational demands. Providing scientific m...

  14. Flight Approach to Adaptive Control Research

    NASA Technical Reports Server (NTRS)

    Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

    2011-01-01

    The National Aeronautics and Space Administration's Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The testbed served as a full-scale vehicle to test and validate adaptive flight control research addressing technical challenges involved with reducing risk to enable safe flight in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

  15. Chaotic satellite attitude control by adaptive approach

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Wang, Jing; Zuo, Min; Liu, Zaiwen; Du, Junping

    2014-06-01

    In this article, chaos control of satellite attitude motion is considered. Adaptive control based on dynamic compensation is utilised to suppress the chaotic behaviour. Control approaches with three control inputs and with only one control input are proposed. Since the adaptive control employed is based on dynamic compensation, faithful model of the system is of no necessity. Sinusoidal disturbance and parameter uncertainties are considered to evaluate the robustness of the closed-loop system. Both of the approaches are confirmed by theoretical and numerical results.

  16. A modular approach to adaptive structures.

    PubMed

    Pagitz, Markus; Pagitz, Manuel; Hühne, Christian

    2014-01-01

    A remarkable property of nastic, shape changing plants is their complete fusion between actuators and structure. This is achieved by combining a large number of cells whose geometry, internal pressures and material properties are optimized for a given set of target shapes and stiffness requirements. An advantage of such a fusion is that cell walls are prestressed by cell pressures which increases, decreases the overall structural stiffness, weight. Inspired by the nastic movement of plants, Pagitz et al (2012 Bioinspir. Biomim. 7) published a novel concept for pressure actuated cellular structures. This article extends previous work by introducing a modular approach to adaptive structures. An algorithm that breaks down any continuous target shapes into a small number of standardized modules is presented. Furthermore it is shown how cytoskeletons within each cell enhance the properties of adaptive modules. An adaptive passenger seat and an aircrafts leading, trailing edge is used to demonstrate the potential of a modular approach. PMID:25289521

  17. Cross-Cultural Adaptation: Current Approaches.

    ERIC Educational Resources Information Center

    Kim, Young Yun, Ed.; Gudykunst, William B., Ed.

    1988-01-01

    Reflecting multidisciplinary and multisocietal approaches, this collection presents 14 theoretical or research-based essays dealing with cross-cultural adaptation of individuals who are born and raised in one culture and find themselves in need of modifying their customary life patterns in a foreign culture. Papers in the collection are:…

  18. A Novel Approach for Adaptive Signal Processing

    NASA Technical Reports Server (NTRS)

    Chen, Ya-Chin; Juang, Jer-Nan

    1998-01-01

    Adaptive linear predictors have been used extensively in practice in a wide variety of forms. In the main, their theoretical development is based upon the assumption of stationarity of the signals involved, particularly with respect to the second order statistics. On this basis, the well-known normal equations can be formulated. If high- order statistical stationarity is assumed, then the equivalent normal equations involve high-order signal moments. In either case, the cross moments (second or higher) are needed. This renders the adaptive prediction procedure non-blind. A novel procedure for blind adaptive prediction has been proposed and considerable implementation has been made in our contributions in the past year. The approach is based upon a suitable interpretation of blind equalization methods that satisfy the constant modulus property and offers significant deviations from the standard prediction methods. These blind adaptive algorithms are derived by formulating Lagrange equivalents from mechanisms of constrained optimization. In this report, other new update algorithms are derived from the fundamental concepts of advanced system identification to carry out the proposed blind adaptive prediction. The results of the work can be extended to a number of control-related problems, such as disturbance identification. The basic principles are outlined in this report and differences from other existing methods are discussed. The applications implemented are speech processing, such as coding and synthesis. Simulations are included to verify the novel modelling method.

  19. The optimal design of service level agreement in IAAS based on BDIM

    NASA Astrophysics Data System (ADS)

    Liu, Xiaochen; Zhan, Zhiqiang

    2013-03-01

    Cloud Computing has become more and more prevalent over the past few years, and we have seen the importance of Infrastructure-as-a-service (IaaS). This kind of service enables scaling of bandwidth, memory, computing power and storage. But the SLA in IaaS also faces complexity and variety. Users also consider the business of the service. To meet the most users requirements, a methodology for designing optimal SLA in IaaS from the business perspectives is proposed. This method is different from the conventional SLA design method, It not only focuses on service provider perspective, also from the customer to carry on the design. This methodology better captures the linkage between service provider and service client by considering minimizing the business loss originated from performance degradation and IT infrastructure failures and maximizing profits for service provider and clients. An optimal design in an IaaS model is provided and an example are analyzed to show this approach obtain higher profit.

  20. Dynamic web cache publishing for IaaS clouds using Shoal

    NASA Astrophysics Data System (ADS)

    Gable, Ian; Chester, Michael; Armstrong, Patrick; Berghaus, Frank; Charbonneau, Andre; Leavett-Brown, Colin; Paterson, Michael; Prior, Robert; Sobie, Randall; Taylor, Ryan

    2014-06-01

    We have developed a highly scalable application, called Shoal, for tracking and utilizing a distributed set of HTTP web caches. Our application uses the Squid HTTP cache. Squid servers advertise their existence to the Shoal server via AMQP messaging by running Shoal Agent. The Shoal server provides a simple REST interface that allows clients to determine their closest Squid cache. Our goal is to dynamically instantiate Squid caches on IaaS clouds in response to client demand. Shoal provides the VMs on IaaS clouds with the location of the nearest dynamically instantiated Squid Cache.

  1. Synergism of VAM and Rhizobium on production and metabolism of IAA in roots and root nodules of Vigna mungo.

    PubMed

    Chakrabarti, Jayanta; Chatterjee, Sabyasachi; Ghosh, Sisir; Chatterjee, Narayan Chandra; Dutta, Sikha

    2010-09-01

    Mature and healthy root nodules of Vigna mungo appeared to contain higher amount of indole-acetic acid (IAA) than non-nodulated roots. Dual effect of VAM fungus, Glomus fasciculatum and the nitrogen-fixing bacteria, Rhizobium sp. on the nodulation of roots of V. mungo was studied. It was recorded that the roots which were inoculated simultaneously with both the symbionts i.e., G. fasciculatum and Rhizobium exhibited greater amount of IAA production than the non-inoculated roots. A tryptophan pool present in the mature nodules and young leaves might serve as a precursor for IAA production in the roots and in the nodules. Activity of IAA-metabolizing enzymes, such as IAA oxidase, peroxidase, and polyphenol oxidase was investigated which indicates the active metabolism of IAA in roots and nodules. The Rhizobium symbiont isolated from fresh nodules of V. mungo produced significant amount of IAA under in vitro condition when tryptophan was added to the medium as precursor. Present study represents some beneficial effects of Rhizobium and G. fasciculatum on the production and metabolism of IAA in roots and nodules of V. mungo. The important physiological implication of the study on IAA production and its metabolism in Rhizobium-Legume-VAM tripartite symbiosis is certainly representing a new approach to satisfy the hormonal balance in the host plant.

  2. Approaching neuropsychological tasks through adaptive neurorobots

    NASA Astrophysics Data System (ADS)

    Gigliotta, Onofrio; Bartolomeo, Paolo; Miglino, Orazio

    2015-04-01

    Neuropsychological phenomena have been modelized mainly, by the mainstream approach, by attempting to reproduce their neural substrate whereas sensory-motor contingencies have attracted less attention. In this work, we introduce a simulator based on the evolutionary robotics platform Evorobot* in order to setting up in silico neuropsychological tasks. Moreover, in this study we trained artificial embodied neurorobotic agents equipped with a pan/tilt camera, provided with different neural and motor capabilities, to solve a well-known neuropsychological test: the cancellation task in which an individual is asked to cancel target stimuli surrounded by distractors. Results showed that embodied agents provided with additional motor capabilities (a zooming/attentional actuator) outperformed simple pan/tilt agents, even those equipped with more complex neural controllers and that the zooming ability is exploited to correctly categorising presented stimuli. We conclude that since the sole neural computational power cannot explain the (artificial) cognition which emerged throughout the adaptive process, such kind of modelling approach can be fruitful in neuropsychological modelling where the importance of having a body is often neglected.

  3. The Limits to Adaptation: A Systems Approach

    EPA Science Inventory

    The ability to adapt to climate change is delineated by capacity thresholds, after which climate damages begin to overwhelm the adaptation response. Such thresholds depend upon physical properties (natural processes and engineering parameters), resource constraints (expressed th...

  4. An Adaptive Critic Approach to Reference Model Adaptation

    NASA Technical Reports Server (NTRS)

    Krishnakumar, K.; Limes, G.; Gundy-Burlet, K.; Bryant, D.

    2003-01-01

    Neural networks have been successfully used for implementing control architectures for different applications. In this work, we examine a neural network augmented adaptive critic as a Level 2 intelligent controller for a C- 17 aircraft. This intelligent control architecture utilizes an adaptive critic to tune the parameters of a reference model, which is then used to define the angular rate command for a Level 1 intelligent controller. The present architecture is implemented on a high-fidelity non-linear model of a C-17 aircraft. The goal of this research is to improve the performance of the C-17 under degraded conditions such as control failures and battle damage. Pilot ratings using a motion based simulation facility are included in this paper. The benefits of using an adaptive critic are documented using time response comparisons for severe damage situations.

  5. Anomalous human behavior detection: an adaptive approach

    NASA Astrophysics Data System (ADS)

    van Leeuwen, Coen; Halma, Arvid; Schutte, Klamer

    2013-05-01

    Detection of anomalies (outliers or abnormal instances) is an important element in a range of applications such as fault, fraud, suspicious behavior detection and knowledge discovery. In this article we propose a new method for anomaly detection and performed tested its ability to detect anomalous behavior in videos from DARPA's Mind's Eye program, containing a variety of human activities. In this semi-unsupervised task a set of normal instances is provided for training, after which unknown abnormal behavior has to be detected in a test set. The features extracted from the video data have high dimensionality, are sparse and inhomogeneously distributed in the feature space making it a challenging task. Given these characteristics a distance-based method is preferred, but choosing a threshold to classify instances as (ab)normal is non-trivial. Our novel aproach, the Adaptive Outlier Distance (AOD) is able to detect outliers in these conditions based on local distance ratios. The underlying assumption is that the local maximum distance between labeled examples is a good indicator of the variation in that neighborhood, and therefore a local threshold will result in more robust outlier detection. We compare our method to existing state-of-art methods such as the Local Outlier Factor (LOF) and the Local Distance-based Outlier Factor (LDOF). The results of the experiments show that our novel approach improves the quality of the anomaly detection.

  6. Russian Loanword Adaptation in Persian; Optimal Approach

    ERIC Educational Resources Information Center

    Kambuziya, Aliye Kord Zafaranlu; Hashemi, Eftekhar Sadat

    2011-01-01

    In this paper we analyzed some of the phonological rules of Russian loanword adaptation in Persian, on the view of Optimal Theory (OT) (Prince & Smolensky, 1993/2004). It is the first study of phonological process on Russian loanwords adaptation in Persian. By gathering about 50 current Russian loanwords, we selected some of them to analyze. We…

  7. VM Capacity-Aware Scheduling within Budget Constraints in IaaS Clouds.

    PubMed

    Thanasias, Vasileios; Lee, Choonhwa; Hanif, Muhammad; Kim, Eunsam; Helal, Sumi

    2016-01-01

    Recently, cloud computing has drawn significant attention from both industry and academia, bringing unprecedented changes to computing and information technology. The infrastructure-as-a-Service (IaaS) model offers new abilities such as the elastic provisioning and relinquishing of computing resources in response to workload fluctuations. However, because the demand for resources dynamically changes over time, the provisioning of resources in a way that a given budget is efficiently utilized while maintaining a sufficing performance remains a key challenge. This paper addresses the problem of task scheduling and resource provisioning for a set of tasks running on IaaS clouds; it presents novel provisioning and scheduling algorithms capable of executing tasks within a given budget, while minimizing the slowdown due to the budget constraint. Our simulation study demonstrates a substantial reduction up to 70% in the overall task slowdown rate by the proposed algorithms. PMID:27501046

  8. VM Capacity-Aware Scheduling within Budget Constraints in IaaS Clouds.

    PubMed

    Thanasias, Vasileios; Lee, Choonhwa; Hanif, Muhammad; Kim, Eunsam; Helal, Sumi

    2016-01-01

    Recently, cloud computing has drawn significant attention from both industry and academia, bringing unprecedented changes to computing and information technology. The infrastructure-as-a-Service (IaaS) model offers new abilities such as the elastic provisioning and relinquishing of computing resources in response to workload fluctuations. However, because the demand for resources dynamically changes over time, the provisioning of resources in a way that a given budget is efficiently utilized while maintaining a sufficing performance remains a key challenge. This paper addresses the problem of task scheduling and resource provisioning for a set of tasks running on IaaS clouds; it presents novel provisioning and scheduling algorithms capable of executing tasks within a given budget, while minimizing the slowdown due to the budget constraint. Our simulation study demonstrates a substantial reduction up to 70% in the overall task slowdown rate by the proposed algorithms.

  9. VM Capacity-Aware Scheduling within Budget Constraints in IaaS Clouds

    PubMed Central

    Thanasias, Vasileios; Lee, Choonhwa; Hanif, Muhammad; Kim, Eunsam; Helal, Sumi

    2016-01-01

    Recently, cloud computing has drawn significant attention from both industry and academia, bringing unprecedented changes to computing and information technology. The infrastructure-as-a-Service (IaaS) model offers new abilities such as the elastic provisioning and relinquishing of computing resources in response to workload fluctuations. However, because the demand for resources dynamically changes over time, the provisioning of resources in a way that a given budget is efficiently utilized while maintaining a sufficing performance remains a key challenge. This paper addresses the problem of task scheduling and resource provisioning for a set of tasks running on IaaS clouds; it presents novel provisioning and scheduling algorithms capable of executing tasks within a given budget, while minimizing the slowdown due to the budget constraint. Our simulation study demonstrates a substantial reduction up to 70% in the overall task slowdown rate by the proposed algorithms. PMID:27501046

  10. The Aux/IAA, Sl-IAA17 regulates quality parameters over tomato fruit development.

    PubMed

    Su, L Y; Audran, C; Bouzayen, M; Roustan, J P; Chervin, C

    2015-01-01

    Auxin is known to be involved in all the stages of fruit development. Aux/IAAs are regulators of the auxin signaling at the transcription level. In a recent study, using RNAi strategy to limit the expression Sl-IAA17, it was shown that this tomato AuxIAA regulates fruit size mainly through altering the ploidy level of pericarp cells. Indeed, Sl-IAA17 down-regulated lines showed fruit with larger diameter, bigger volume and heavier weight than wild-type. The increase in fruit size was associated with thicker pericarp rather than larger locular spaces. The thicker pericarp was linked to larger cells harboring higher ploidy level, probably due to more active endoreduplication at the beginning of fruit development. The present report describes some additional phenotypes, not described in the initial article, among which are soluble solid content, juice pH, firmness, seed weight and fruit morphology.

  11. Passive and active adaptive management: Approaches and an example

    USGS Publications Warehouse

    Williams, B.K.

    2011-01-01

    Adaptive management is a framework for resource conservation that promotes iterative learning-based decision making. Yet there remains considerable confusion about what adaptive management entails, and how to actually make resource decisions adaptively. A key but somewhat ambiguous distinction in adaptive management is between active and passive forms of adaptive decision making. The objective of this paper is to illustrate some approaches to active and passive adaptive management with a simple example involving the drawdown of water impoundments on a wildlife refuge. The approaches are illustrated for the drawdown example, and contrasted in terms of objectives, costs, and potential learning rates. Some key challenges to the actual practice of AM are discussed, and tradeoffs between implementation costs and long-term benefits are highlighted. ?? 2010 Elsevier Ltd.

  12. Monitoring of IaaS and scientific applications on the Cloud using the Elasticsearch ecosystem

    NASA Astrophysics Data System (ADS)

    Bagnasco, S.; Berzano, D.; Guarise, A.; Lusso, S.; Masera, M.; Vallero, S.

    2015-05-01

    The private Cloud at the Torino INFN computing centre offers IaaS services to different scientific computing applications. The infrastructure is managed with the OpenNebula cloud controller. The main stakeholders of the facility are a grid Tier-2 site for the ALICE collaboration at LHC, an interactive analysis facility for the same experiment and a grid Tier-2 site for the BES-III collaboration, plus an increasing number of other small tenants. Besides keeping track of the usage, the automation of dynamic allocation of resources to tenants requires detailed monitoring and accounting of the resource usage. As a first investigation towards this, we set up a monitoring system to inspect the site activities both in terms of IaaS and applications running on the hosted virtual instances. For this purpose we used the Elasticsearch, Logstash and Kibana stack. In the current implementation, the heterogeneous accounting information is fed to different MySQL databases and sent to Elasticsearch via a custom Logstash plugin. For the IaaS metering, we developed sensors for the OpenNebula API. The IaaS level information gathered through the API is sent to the MySQL database through an ad-hoc developed RESTful web service, which is also used for other accounting purposes. Concerning the application level, we used the Root plugin TProofMonSenderSQL to collect accounting data from the interactive analysis facility. The BES-III virtual instances used to be monitored with Zabbix, as a proof of concept we also retrieve the information contained in the Zabbix database. Each of these three cases is indexed separately in Elasticsearch. We are now starting to consider dismissing the intermediate level provided by the SQL database and evaluating a NoSQL option as a unique central database for all the monitoring information. We setup a set of Kibana dashboards with pre-defined queries in order to monitor the relevant information in each case. In this way we have achieved a uniform monitoring

  13. On adaptive robustness approach to Anti-Jam signal processing

    NASA Astrophysics Data System (ADS)

    Poberezhskiy, Y. S.; Poberezhskiy, G. Y.

    An effective approach to exploiting statistical differences between desired and jamming signals named adaptive robustness is proposed and analyzed in this paper. It combines conventional Bayesian, adaptive, and robust approaches that are complementary to each other. This combining strengthens the advantages and mitigates the drawbacks of the conventional approaches. Adaptive robustness is equally applicable to both jammers and their victim systems. The capabilities required for realization of adaptive robustness in jammers and victim systems are determined. The employment of a specific nonlinear robust algorithm for anti-jam (AJ) processing is described and analyzed. Its effectiveness in practical situations has been proven analytically and confirmed by simulation. Since adaptive robustness can be used by both sides in electronic warfare, it is more advantageous for the fastest and most intelligent side. Many results obtained and discussed in this paper are also applicable to commercial applications such as communications in unregulated or poorly regulated frequency ranges and systems with cognitive capabilities.

  14. [Molecular cloning and expression analysis of an Aux/IAA gene (RgIAA1) from Rehmannia glutinosa].

    PubMed

    Wang, Feng-Qing; Tian, Yun-He; Li, Ming-Jie; Yang, Jin-Feng; Zhang, Bao; Lin, Wen-Xiong; Chen, Xin-Jian; Zhang, Zhong-Yi

    2013-12-01

    To clone and analyze a member of the Auxin/indole-3-acetic acid (Aux/IAA) gene family, RgIAA1, from Rehmannia glutinosa. The transcriptional EST database of R. glutinosa was used to clone the new Aux/IAA gene by cDNA probe of AtIAA14. Bioinformatics was applied to analyze the sequence characteristics of RgIAA1 protein and construct phylogenetiC trees. Quantitative RT-PCR has been applied to detect the transcription level of RgIAA1 in seven tissues as well as in leaves under three stresses. The results showed that, the cDNA sequence of RgIAA1 contains 903 bp was obtained. The open reading frame (ORF) of RgIAA1 was 681 bp encoding 226 amino acids, which has typical structural domains and characteristic sequence of Aux/IAA family proteins. RgIAA1 showed the highest expression level in unfolded leaf, followed by the stem. And the expression of RglAA1 was quickly decreased with leaf growing up. The transcription level increased under continuous cropping conditions while it reduced both in salinity and waterlogging stresses. RgIAA1, an Aux/IAA gene from R. glutinosa has been obtained for the first time, which can lay the foundation for further studies about its molecular function in development and responses to stress.

  15. IAA RAS Radio Telescope Monitoring System

    NASA Astrophysics Data System (ADS)

    Mikhailov, A.; Lavrov, A.

    2007-07-01

    Institute of Applied Astronomy of the Russian Academy of Sciences (IAA RAS) has three identical radio telescopes, the receiving complex of which consists of five two-channel receivers of different bands, six cryogen systems, and additional devices: four local oscillators, phase calibration generators and IF commutator. The design, hardware and data communication protocol are described. The most convenient way to join the devices of the receiving complex into the common monitoring system is to use the interface which allows to connect numerous devices to the data bus. For the purpose of data communication regulation and to exclude conflicts, a data communication protocol has been designed, which operates with complex formatted data sequences. Formation of such sequences requires considerable data processing capability. That is provided by a microcontroller chip in each slave device. The test version of the software for the central computer has been developed in IAA RAS. We are developing the Mark IV FS software extension modules, which will allow us to control the receiving complex of the radio telescope by special SNAP commands from both operator input and schedule files. We are also developing procedures of automatic measurements of SEFD, system noise temperature and other parameters, available both in VLBI and single-dish modes of operation. The system described has been installed on all IAA RAS radio telescopes at "Svetloe", "Zelenchukskaya" and "Badary" observatories. It has proved to be working quite reliably and to show the perfonmance expected.

  16. Probing waveforms and adaptive receivers for active sonar.

    PubMed

    Ling, Jun; Li, Jian; Stoica, Petre; Datum, Michael

    2011-06-01

    Active sonar systems involve the transmission and reception of one or more probing sequences, which provide a basis for extraction of target information in a region of interest. The probing sequences at the transmitter and signal processing at the receiver play crucial roles in the overall system performance. In this paper, CAN (cyclic algorithm-new) is employed to synthesize probing sequences with good aperiodic autocorrelation properties. The performance of the CAN sequences will be compared with those of pseudo random noise and random phase sequences. Two adaptive receiver designs, namely the iterative adaptive approach (IAA) and the sparse learning via iterative minimization (SLIM) method, will also be considered. IAA and SLIM will be compared with the conventional matched filter method. The performances of the algorithms will be illustrated via numerical examples, which show that CAN, IAA, and SLIM can contribute to the overall performance improvement of the active sonar systems.

  17. Approach for reconstructing anisoplanatic adaptive optics images.

    PubMed

    Aubailly, Mathieu; Roggemann, Michael C; Schulz, Timothy J

    2007-08-20

    Atmospheric turbulence corrupts astronomical images formed by ground-based telescopes. Adaptive optics systems allow the effects of turbulence-induced aberrations to be reduced for a narrow field of view corresponding approximately to the isoplanatic angle theta(0). For field angles larger than theta(0), the point spread function (PSF) gradually degrades as the field angle increases. We present a technique to estimate the PSF of an adaptive optics telescope as function of the field angle, and use this information in a space-varying image reconstruction technique. Simulated anisoplanatic intensity images of a star field are reconstructed by means of a block-processing method using the predicted local PSF. Two methods for image recovery are used: matrix inversion with Tikhonov regularization, and the Lucy-Richardson algorithm. Image reconstruction results obtained using the space-varying predicted PSF are compared to space invariant deconvolution results obtained using the on-axis PSF. The anisoplanatic reconstruction technique using the predicted PSF provides a significant improvement of the mean squared error between the reconstructed image and the object compared to the deconvolution performed using the on-axis PSF. PMID:17712366

  18. Brain source localization based on fast fully adaptive approach.

    PubMed

    Ravan, Maryam; Reilly, James P

    2012-01-01

    In the electroencephalogram (EEG) or magnetoencephalogram (MEG) context, brain source localization (beamforming) methods often fail when the number of observations is small. This is particularly true when measuring evoked potentials, especially when the number of electrodes is large. Due to the nonstationarity of the EEG/MEG, an adaptive capability is desirable. Previous work has addressed these issues by reducing the adaptive degrees of freedom (DoFs). This paper develops and tests a new multistage adaptive processing for brain source localization that has been previously used for radar statistical signal processing application with uniform linear antenna array. This processing, referred to as the fast fully adaptive (FFA) approach, could significantly reduce the required sample support and computational complexity, while still processing all available DoFs. The performance improvement offered by the FFA approach in comparison to the fully adaptive minimum variance beamforming (MVB) with limited data is demonstrated by bootstrapping simulated data to evaluate the variability of the source location.

  19. [An adapted relational approach to hospitalised adolescents].

    PubMed

    Naville, Lydie

    2011-01-01

    The treatment of an adolescent hospitalised in paediatrics often poses difficulties. The relational aspect of the nurse's work in this period of development between childhood and adulthood remains delicate in a context of institutionalisation. What is the interaction between the relational approach and the adolescent's experience of hospitalisation in paediatrics?

  20. [An adapted relational approach to hospitalised adolescents].

    PubMed

    Naville, Lydie

    2011-01-01

    The treatment of an adolescent hospitalised in paediatrics often poses difficulties. The relational aspect of the nurse's work in this period of development between childhood and adulthood remains delicate in a context of institutionalisation. What is the interaction between the relational approach and the adolescent's experience of hospitalisation in paediatrics? PMID:21520581

  1. Staged sacrectomy--an adaptive approach.

    PubMed

    Ramamurthy, Rajaraman; Bose, Jagadish Chandra; Muthusamy, Vimalakannan; Natarajan, Mayilvahanan; Kunjithapatham, Deiveegan

    2009-09-01

    Object Sacral tumors are commonly diagnosed late and therefore present at an advanced stage. The late presentation makes curative surgery technically demanding. Sacrectomy is fraught with a high local recurrence rate and potential complications: deep infection; substantial blood loss; large-bone and soft-tissue defects; bladder, bowel, and sexual dysfunction; spinopelvic nonunion; and gait disturbance. The aim of this study was to analyze the complications and morbidity of sacrectomy and the modifications meant to reduce the morbidity. Methods This is a retrospective study of the patients who underwent sacrectomy between February 1997 and September 2008 in the Department of Surgical Oncology, Government Royapettah Hospital, Kilpauk Medical College, in Chennai, Tamilnadu, India. Sacrectomy was performed using 1 of the following approaches: posterior approach, abdominolateral approach, or abdominosacral approach, either as sequential or staged operations. The morbidity rate after the sequential and staged abdominosacral approaches was analyzed. Functional assessment was made based on the Enneking functional scoring system. The results were analyzed and survival analysis was done using the Kaplan-Meier method (with SPSS software). Results Nineteen patients underwent sacrectomy, of which 12 operations were partial, 3 were subtotal, and 4 were total sacrectomy. Histological diagnosis included giant cell tumor, chordoma, chondroblastoma, adenocarcinoma of rectum, and retroperitoneal sarcoma. The giant cell tumor was the most common tumor in this series, followed by chordoma. The patients' mean age at diagnosis was 32 years. There were 10 male and 9 female patients. Fortyseven percent of patients had bowel and bladder disturbances postoperatively, and 57.89% of patients had wound complications. The median follow-up duration was 24 months (range 2-140 months). The 5-year overall survival rate was 70.4%, and the 5-year disease-free survival rate was 65% (based on the Kaplan

  2. NGAP: A (Brief) Update PaaS, IaaS, Onbording, and the Future

    NASA Technical Reports Server (NTRS)

    McLaughlin, Brett; Pawloski, Andrew

    2016-01-01

    NASA ESDIS has charged the EED2 program with delivering a NASA-compliant, secure, cloud-based platform for application hosting. More than just a move to the cloud, this has forced us to examine all aspects of application hosting, from resource management to system administration, patching to monitoring, deployment to multiple environments. The result of this mandate is NGAP, the NASA General Application Platform. In this presentation, we will also discuss the various applications we are supporting and targeting, and their architectures including NGAPs move to support both PaaS and IaaS architectures.

  3. Adapting to the Digital Age: A Narrative Approach

    ERIC Educational Resources Information Center

    Cousins, Sarah; Bissar, Dounia

    2012-01-01

    The article adopts a narrative inquiry approach to foreground informal learning and exposes a collection of stories from tutors about how they adapted comfortably to the digital age.We were concerned that despite substantial evidence that bringing about changes in pedagogic practices can be difficult, there is a gap in convincing approaches to…

  4. Identification and Analyses of AUX-IAA target genes controlling multiple pathways in developing fiber cells of Gossypium hirsutum L.

    PubMed

    Nigam, Deepti; Sawant, Samir V

    2013-01-01

    Technological development led to an increased interest in systems biological approaches in plants to characterize developmental mechanism and candidate genes relevant to specific tissue or cell morphology. AUX-IAA proteins are important plant-specific putative transcription factors. There are several reports on physiological response of this family in Arabidopsis but in cotton fiber the transcriptional network through which AUX-IAA regulated its target genes is still unknown. in-silico modelling of cotton fiber development specific gene expression data (108 microarrays and 22,737 genes) using Algorithm for the Reconstruction of Accurate Cellular Networks (ARACNe) reveals 3690 putative AUX-IAA target genes of which 139 genes were known to be AUX-IAA co-regulated within Arabidopsis. Further AUX-IAA targeted gene regulatory network (GRN) had substantial impact on the transcriptional dynamics of cotton fiber, as showed by, altered TF networks, and Gene Ontology (GO) biological processes and metabolic pathway associated with its target genes. Analysis of the AUX-IAA-correlated gene network reveals multiple functions for AUX-IAA target genes such as unidimensional cell growth, cellular nitrogen compound metabolic process, nucleosome organization, DNA-protein complex and process related to cell wall. These candidate networks/pathways have a variety of profound impacts on such cellular functions as stress response, cell proliferation, and cell differentiation. While these functions are fairly broad, their underlying TF networks may provide a global view of AUX-IAA regulated gene expression and a GRN that guides future studies in understanding role of AUX-IAA box protein and its targets regulating fiber development.

  5. A genetic screen for mutants defective in IAA1-LUC degradation in Arabidopsis thaliana reveals an important requirement for TOPOISOMERASE6B in auxin physiology

    PubMed Central

    Gilkerson, Jonathan; Callis, Judy

    2014-01-01

    Many plant growth and developmental processes are modulated by the hormone auxin. Auxin-modulated proteolysis of Aux/IAAs, a family of transcriptional repressors, represents a major mode of auxin action. Auxin facilitates the interaction of Aux/IAAs with TIR1/AFB F-box proteins, promoting their ubiquitination by the SCFTIR1/AFB ubiquitin E3 ligase leading to subsequent degradation by the 26S proteasome. To identify new genes regulating Aux/IAA proteolysis in Arabidopsis thaliana, we took a genetic approach, identifying individuals with altered degradation of an IAA1-luciferase fusion protein (IAA1-LUC). A mutant with 2-fold slower IAA1-LUC degradation rate compared with wild-type was isolated. Positional cloning identified the mutant as an allele of TOPOISOMERASE6B, named top6b-7. TOP6B encodes a subunit of a plant and archea-specific enzyme regulating endoreduplication, DNA damage repair and transcription in plants. T-DNA insertion alleles (top6b-8 and top6b-9) were also analyzed. top6b-7 seedlings are less sensitive to exogenous auxin than wild-type siblings in primary root growth assays, and experiments with DR5:GUS. Additionally, top6b-7 seedlings have a 40% reduction in the amount of endogenous IAA. These data suggest that increased IAA1-LUC half-life in top6b-7 probably results from a combination of both lower endogenous IAA levels and reduced sensitivity to auxin. PMID:25482814

  6. The IAA RAS Correlator First Results

    NASA Technical Reports Server (NTRS)

    Surkis, Igor; Melnikov, Alexey; Shantyr, Violet; Zimovsky, Vladimir

    2010-01-01

    In 2009 the national Russian VLBI observations were processed by the new correlator ARC (Astrometric Radiointerferometric Correlator). The ARC is a VSI-H correlator and equipped with Mark 5B playback terminals. During 2009 ARC was used to process a series of VLBI sessions, observed on stations Svetloe, Zelenchukskaya, and Badary. NGS files were formed, and EOP parameters were obtained by IAA RAS Analysis Center. The accuracies of the pole coordinates and UT1-UTC were 1-2 mas and 0.07-0.1 ms, respectively.

  7. The tomato Aux/IAA transcription factor IAA9 is involved in fruit development and leaf morphogenesis.

    PubMed

    Wang, Hua; Jones, Brian; Li, Zhengguo; Frasse, Pierre; Delalande, Corinne; Regad, Farid; Chaabouni, Salma; Latché, Alain; Pech, Jean-Claude; Bouzayen, Mondher

    2005-10-01

    Auxin/indole-3-acetic acid (Aux/IAA) proteins are transcriptional regulators that mediate many aspects of plant responses to auxin. While functions of most Aux/IAAs have been defined mainly by gain-of-function mutant alleles in Arabidopsis thaliana, phenotypes associated with loss-of-function mutations have been scarce and subtle. We report here that the downregulation of IAA9, a tomato (Solanum lycopersicum) gene from a distinct subfamily of Aux/IAA genes, results in a pleiotropic phenotype, consistent with its ubiquitous expression pattern. IAA9-inhibited lines have simple leaves instead of wild-type compound leaves, and fruit development is triggered before fertilization, giving rise to parthenocarpy. This indicates that IAA9 is a key mediator of leaf morphogenesis and fruit set. In addition, antisense plants displayed auxin-related growth alterations, including enhanced hypocotyl/stem elongation, increased leaf vascularization, and reduced apical dominance. Auxin dose-response assays revealed that IAA9 downregulated lines were hypersensitive to auxin, although the only early auxin-responsive gene that was found to be upregulated in the antisense lines was IAA3. The activity of the IAA3 promoter was stimulated in the IAA9 antisense genetic background, indicating that IAA9 acts in planta as a transcriptional repressor of auxin signaling. While no mutation in any member of subfamily IV has been reported to date, the phenotypes associated with the downregulation of IAA9 reveal distinct and novel roles for members of the Aux/IAA gene family. PMID:16126837

  8. A batch system for HEP applications on a distributed IaaS cloud

    NASA Astrophysics Data System (ADS)

    Gable, I.; Agarwal, A.; Anderson, M.; Armstrong, P.; Fransham, K.; Leavett-Brown, D. Harris C.; Paterson, M.; Penfold-Brown, D.; Sobie, R. J.; Vliet, M.; Charbonneau, A.; Impey, R.; Podaima, W.

    2011-12-01

    The emergence of academic and commercial Infrastructure-as-a-Service (IaaS) clouds is opening access to new resources for the HEP community. In this paper we will describe a system we have developed for creating a single dynamic batch environment spanning multiple IaaS clouds of different types (e.g. Nimbus, OpenNebula, Amazon EC2). A HEP user interacting with the system submits a job description file with a pointer to their VM image. VM images can either be created by users directly or provided to the users. We have created a new software component called Cloud Scheduler that detects waiting jobs and boots the user VM required on any one of the available cloud resources. As the user VMs appear, they are attached to the job queues of a central Condor job scheduler, the job scheduler then submits the jobs to the VMs. The number of VMs available to the user is expanded and contracted dynamically depending on the number of user jobs. We present the motivation and design of the system with particular emphasis on Cloud Scheduler. We show that the system provides the ability to exploit academic and commercial cloud sites in a transparent fashion.

  9. The AdaptiV Approach to Verification of Adaptive Systems

    SciTech Connect

    Rouff, Christopher; Buskens, Richard; Pullum, Laura L; Cui, Xiaohui; Hinchey, Mike

    2012-01-01

    Adaptive systems are critical for future space and other unmanned and intelligent systems. Verification of these systems is also critical for their use in systems with potential harm to human life or with large financial investments. Due to their nondeterministic nature and extremely large state space, current methods for verification of software systems are not adequate to provide a high level of assurance. The combination of stabilization science, high performance computing simulations, compositional verification and traditional verification techniques, plus operational monitors, provides a complete approach to verification and deployment of adaptive systems that has not been used before. This paper gives an overview of this approach.

  10. A Decentralized Adaptive Approach to Fault Tolerant Flight Control

    NASA Technical Reports Server (NTRS)

    Wu, N. Eva; Nikulin, Vladimir; Heimes, Felix; Shormin, Victor

    2000-01-01

    This paper briefly reports some results of our study on the application of a decentralized adaptive control approach to a 6 DOF nonlinear aircraft model. The simulation results showed the potential of using this approach to achieve fault tolerant control. Based on this observation and some analysis, the paper proposes a multiple channel adaptive control scheme that makes use of the functionally redundant actuating and sensing capabilities in the model, and explains how to implement the scheme to tolerate actuator and sensor failures. The conditions, under which the scheme is applicable, are stated in the paper.

  11. A new approach to adaptive control of manipulators

    NASA Technical Reports Server (NTRS)

    Seraji, H.

    1987-01-01

    An approach in which the manipulator inverse is used as a feedforward controller is employed in the adaptive control of manipulators in order to achieve trajectory tracking by the joint angles. The desired trajectory is applied as an input to the feedforward controller, and the controller output is used as the driving torque for the manipulator. An adaptive algorithm obtained from MRAC theory is used to update the controller gains to cope with variations in the manipulator inverse due to changes of the operating point. An adaptive feedback controller and an auxiliary signal enhance closed-loop stability and achieve faster adaptation. Simulation results demonstrate the effectiveness of the proposed control scheme for different reference trajectories, and despite large variations in the payload.

  12. Optimal Decision Stimuli for Risky Choice Experiments: An Adaptive Approach.

    PubMed

    Cavagnaro, Daniel R; Gonzalez, Richard; Myung, Jay I; Pitt, Mark A

    2013-02-01

    Collecting data to discriminate between models of risky choice requires careful selection of decision stimuli. Models of decision making aim to predict decisions across a wide range of possible stimuli, but practical limitations force experimenters to select only a handful of them for actual testing. Some stimuli are more diagnostic between models than others, so the choice of stimuli is critical. This paper provides the theoretical background and a methodological framework for adaptive selection of optimal stimuli for discriminating among models of risky choice. The approach, called Adaptive Design Optimization (ADO), adapts the stimulus in each experimental trial based on the results of the preceding trials. We demonstrate the validity of the approach with simulation studies aiming to discriminate Expected Utility, Weighted Expected Utility, Original Prospect Theory, and Cumulative Prospect Theory models. PMID:24532856

  13. Optimal Decision Stimuli for Risky Choice Experiments: An Adaptive Approach

    PubMed Central

    Cavagnaro, Daniel R.; Gonzalez, Richard; Myung, Jay I.; Pitt, Mark A.

    2014-01-01

    Collecting data to discriminate between models of risky choice requires careful selection of decision stimuli. Models of decision making aim to predict decisions across a wide range of possible stimuli, but practical limitations force experimenters to select only a handful of them for actual testing. Some stimuli are more diagnostic between models than others, so the choice of stimuli is critical. This paper provides the theoretical background and a methodological framework for adaptive selection of optimal stimuli for discriminating among models of risky choice. The approach, called Adaptive Design Optimization (ADO), adapts the stimulus in each experimental trial based on the results of the preceding trials. We demonstrate the validity of the approach with simulation studies aiming to discriminate Expected Utility, Weighted Expected Utility, Original Prospect Theory, and Cumulative Prospect Theory models. PMID:24532856

  14. Searching for adaptive traits in genetic resources - phenology based approach

    NASA Astrophysics Data System (ADS)

    Bari, Abdallah

    2015-04-01

    Searching for adaptive traits in genetic resources - phenology based approach Abdallah Bari, Kenneth Street, Eddy De Pauw, Jalal Eddin Omari, and Chandra M. Biradar International Center for Agricultural Research in the Dry Areas, Rabat Institutes, Rabat, Morocco Phenology is an important plant trait not only for assessing and forecasting food production but also for searching in genebanks for adaptive traits. Among the phenological parameters we have been considering to search for such adaptive and rare traits are the onset (sowing period) and the seasonality (growing period). Currently an application is being developed as part of the focused identification of germplasm strategy (FIGS) approach to use climatic data in order to identify crop growing seasons and characterize them in terms of onset and duration. These approximations of growing period characteristics can then be used to estimate flowering and maturity dates for dryland crops, such as wheat, barley, faba bean, lentils and chickpea, and assess, among others, phenology-related traits such as days to heading [dhe] and grain filling period [gfp]. The approach followed here is based on first calculating long term average daily temperatures by fitting a curve to the monthly data over days from beginning of the year. Prior to the identification of these phenological stages the onset is extracted first from onset integer raster GIS layers developed based on a model of the growing period that considers both moisture and temperature limitations. The paper presents some examples of real applications of the approach to search for rare and adaptive traits.

  15. G2LC: Resources Autoscaling for Real Time Bioinformatics Applications in IaaS

    PubMed Central

    Hu, Rongdong; Liu, Guangming; Jiang, Jingfei; Wang, Lixin

    2015-01-01

    Cloud computing has started to change the way how bioinformatics research is being carried out. Researchers who have taken advantage of this technology can process larger amounts of data and speed up scientific discovery. The variability in data volume results in variable computing requirements. Therefore, bioinformatics researchers are pursuing more reliable and efficient methods for conducting sequencing analyses. This paper proposes an automated resource provisioning method, G2LC, for bioinformatics applications in IaaS. It enables application to output the results in a real time manner. Its main purpose is to guarantee applications performance, while improving resource utilization. Real sequence searching data of BLAST is used to evaluate the effectiveness of G2LC. Experimental results show that G2LC guarantees the application performance, while resource is saved up to 20.14%. PMID:26504488

  16. G2LC: Resources Autoscaling for Real Time Bioinformatics Applications in IaaS.

    PubMed

    Hu, Rongdong; Liu, Guangming; Jiang, Jingfei; Wang, Lixin

    2015-01-01

    Cloud computing has started to change the way how bioinformatics research is being carried out. Researchers who have taken advantage of this technology can process larger amounts of data and speed up scientific discovery. The variability in data volume results in variable computing requirements. Therefore, bioinformatics researchers are pursuing more reliable and efficient methods for conducting sequencing analyses. This paper proposes an automated resource provisioning method, G2LC, for bioinformatics applications in IaaS. It enables application to output the results in a real time manner. Its main purpose is to guarantee applications performance, while improving resource utilization. Real sequence searching data of BLAST is used to evaluate the effectiveness of G2LC. Experimental results show that G2LC guarantees the application performance, while resource is saved up to 20.14%.

  17. A special adapted retractor for the mini-sternotomy approach.

    PubMed

    Massetti, M; Babatasi, G; Bhoyroo, S; Le Page, O; Khayat, A

    1999-07-01

    Minimally invasive cardiac operations are now possible through different approaches. To provide the best exposure and sufficient space to manipulate the heart, a special adapted thoracic retractor has been developed for the ministernotomy approach. It is universally adjustable and provides excellent and consistent exposure especially below the incision edges. The retractor has the further advantage of a very low profile on the surgeon's side and at the cephalic and caudal extremes of the operative field, which permits the greatest possible access through a limited access. We have successfully used this retractor in more than 180 patients. A less invasive median sternotomy through a 6-9-cm incision has been our original approach.

  18. An information theoretic approach of designing sparse kernel adaptive filters.

    PubMed

    Liu, Weifeng; Park, Il; Principe, José C

    2009-12-01

    This paper discusses an information theoretic approach of designing sparse kernel adaptive filters. To determine useful data to be learned and remove redundant ones, a subjective information measure called surprise is introduced. Surprise captures the amount of information a datum contains which is transferable to a learning system. Based on this concept, we propose a systematic sparsification scheme, which can drastically reduce the time and space complexity without harming the performance of kernel adaptive filters. Nonlinear regression, short term chaotic time-series prediction, and long term time-series forecasting examples are presented. PMID:19923047

  19. An information theoretic approach of designing sparse kernel adaptive filters.

    PubMed

    Liu, Weifeng; Park, Il; Principe, José C

    2009-12-01

    This paper discusses an information theoretic approach of designing sparse kernel adaptive filters. To determine useful data to be learned and remove redundant ones, a subjective information measure called surprise is introduced. Surprise captures the amount of information a datum contains which is transferable to a learning system. Based on this concept, we propose a systematic sparsification scheme, which can drastically reduce the time and space complexity without harming the performance of kernel adaptive filters. Nonlinear regression, short term chaotic time-series prediction, and long term time-series forecasting examples are presented.

  20. Novel Approaches to Adaptive Angular Approximations in Computational Transport

    SciTech Connect

    Marvin L. Adams; Igor Carron; Paul Nelson

    2006-06-04

    The particle-transport equation is notoriously difficult to discretize accurately, largely because the solution can be discontinuous in every variable. At any given spatial position and energy E, for example, the transport solution  can be discontinuous at an arbitrary number of arbitrary locations in the direction domain. Even if the solution is continuous it is often devoid of smoothness. This makes the direction variable extremely difficult to discretize accurately. We have attacked this problem with adaptive discretizations in the angle variables, using two distinctly different approaches. The first approach used wavelet function expansions directly and exploited their ability to capture sharp local variations. The second used discrete ordinates with a spatially varying quadrature set that adapts to the local solution. The first approach is very different from that in today’s transport codes, while the second could conceivably be implemented in such codes. Both approaches succeed in reducing angular discretization error to any desired level. The work described and results presented in this report add significantly to the understanding of angular discretization in transport problems and demonstrate that it is possible to solve this important long-standing problem in deterministic transport. Our results show that our adaptive discrete-ordinates (ADO) approach successfully: 1) Reduces angular discretization error to user-selected “tolerance” levels in a variety of difficult test problems; 2) Achieves a given error with significantly fewer unknowns than non-adaptive discrete ordinates methods; 3) Can be implemented within standard discrete-ordinates solution techniques, and thus could generate a significant impact on the field in a relatively short time. Our results show that our adaptive wavelet approach: 1) Successfully reduces the angular discretization error to arbitrarily small levels in a variety of difficult test problems, even when using the

  1. An Approach to V&V of Embedded Adaptive Systems

    NASA Technical Reports Server (NTRS)

    Liu, Yan; Yerramalla, Sampath; Fuller, Edgar; Cukic, Bojan; Gururajan, Srikaruth

    2004-01-01

    Rigorous Verification and Validation (V&V) techniques are essential for high assurance systems. Lately, the performance of some of these systems is enhanced by embedded adaptive components in order to cope with environmental changes. Although the ability of adapting is appealing, it actually poses a problem in terms of V&V. Since uncertainties induced by environmental changes have a significant impact on system behavior, the applicability of conventional V&V techniques is limited. In safety-critical applications such as flight control system, the mechanisms of change must be observed, diagnosed, accommodated and well understood prior to deployment. In this paper, we propose a non-conventional V&V approach suitable for online adaptive systems. We apply our approach to an intelligent flight control system that employs a particular type of Neural Networks (NN) as the adaptive learning paradigm. Presented methodology consists of a novelty detection technique and online stability monitoring tools. The novelty detection technique is based on Support Vector Data Description that detects novel (abnormal) data patterns. The Online Stability Monitoring tools based on Lyapunov's Stability Theory detect unstable learning behavior in neural networks. Cases studies based on a high fidelity simulator of NASA's Intelligent Flight Control System demonstrate a successful application of the presented V&V methodology. ,

  2. Adaptation in flower form: a comparative evodevo approach.

    PubMed

    Specht, Chelsea D; Howarth, Dianella G

    2015-04-01

    Evolutionary developmental biology (evodevo) attempts to explain how the process of organismal development evolves, utilizing a comparative approach to investigate changes in developmental pathways and processes that occur during the evolution of a given lineage. Evolutionary genetics uses a population approach to understand how organismal changes in form or function are linked to underlying genetics, focusing on changes in gene and genotype frequencies within populations and the fixation of genotypic variation into traits that define species or evoke speciation events. Microevolutionary processes, including mutation, genetic drift, natural selection and gene flow, can provide the foundation for macroevolutionary patterns observed as morphological evolution and adaptation. The temporal element linking microevolutionary processes to macroevolutionary patterns is development: an organism's genotype is converted to phenotype by ontogenetic processes. Because selection acts upon the phenotype, the connection between evolutionary genetics and developmental evolution becomes essential to understanding adaptive evolution in organismal form and function. Here, we discuss how developmental genetic studies focused on key developmental processes could be linked within a comparative framework to study the developmental genetics of adaptive evolution, providing examples from research on two key processes of plant evodevo - floral symmetry and organ fusion - and their role in the adaptation of floral form. PMID:25470511

  3. The adaptive, cut-cell Cartesian approach (warts and all)

    NASA Astrophysics Data System (ADS)

    Powell, Kenneth G.

    1995-10-01

    Solution-adaptive methods based on cutting bodies out of Cartesian grids are gaining popularity now that the ways of circumventing the accuracy problems associated with small cut cells have been developed. Researchers are applying Cartesian-based schemes to a broad class of problems now, and, although there is still development work to be done, it is becoming clearer which problems are best suited to the approach (and which are not). The purpose of this paper is to give a candid assessment, based on applying Cartesian schemes to a variety of problems, of the strengths and weaknesses of the approach as it is currently implemented.

  4. An Approach for Prioritizing Agile Practices for Adaptation

    NASA Astrophysics Data System (ADS)

    Mikulenas, Gytenis; Kapocius, Kestutis

    Agile software development approaches offer a strong alternative to the traditional plan-driven methodologies that have not been able to warrant successfulness of the software projects. However, the move toward Agile is often hampered by the wealth of alternative practices that are accompanied by numerous success or failure stories. Clearly, the formal methods for choosing most suitable practices are lacking. In this chapter, we present an overview of this problem and propose an approach for prioritization of available practices in accordance to the particular circumstances. The proposal combines ideas from Analytic Hierarchy Process (AHP) decision-making technique, cost-value analysis, and Rule-Description-Practice (RDP) technique. Assumption that such approach could facilitate the Agile adaptation process was supported by the case study of the approach illustrating the process of choosing most suitable Agile practices within a real-life project.

  5. Status of the IAA study group on traffic management rules for space operations

    NASA Astrophysics Data System (ADS)

    Contant, Corinne; Lala, Petr; Schrogl, Kai-Uwe

    2007-10-01

    The investigation of space traffic and its management has only recently become a point of wider discussion. In particular, the series of workshops organized by the American Institute of Aeronautics and Astronautics (AIAA) and other international organizations on international cooperation highlighted the issue. It was discussed thoroughly at the workshops, which took place in 1999 and 2001, respectively. It was at the 2001 workshop, when the suggestion was made that an International Academy of Astronautics (IAA) Study on the subject of space traffic management should be prepared. This suggestion was taken up and a proposal was presented to the Board of Trustees of IAA, which, in late 2001, accepted this proposal. Following this, an interdisciplinary study group of around 20 persons was composed. One early milestone in the process of work was the conduct of an International Institute of Space Law (IISL)/European Center of Space Law (ECSL) Symposium alongside the 2002 session of the United Nations Committee on the Peaceful Uses of Outer Space (UNCOPUOS) Legal Subcommittee. This symposium consisted of presentations of members of the IAA study group. Also, close coordination with other study projects of IAA, in particular with the one on space debris, is sought. This paper presents the status of work of the study group, in particular, the approach and the scope of the study as well as its preliminary findings. The study group intends to finalize its work in early 2004, in order to be able to put the study before IAA and launch its review process before the 2004 International Astronautical Congress. Following this review, the study will be published and may be expected to make an impact in fora like the UNCOPUOS. The authors of this paper act as the coordinators/the rapporteur to this study. The paper will be presented in the IAA—as well as the IISL—session dealing with space traffic, by that bridging the two areas and seeking input from various sources.

  6. [Effect of IAA on the photophosphorylation of pea isolated chloroplasts].

    PubMed

    Akulova, E A; Murzaeva, S V; Taukeleva, Sh N; Ruzieva, R Kh

    1975-01-01

    Effect of IAA (10(-10)-10(-3) M) on photophosphorylation, NADP reduction and the oxygen exchange is investigated. It is shown that low concentrations of IAA (10(-10)-10(-7) M) increase the photophosphorylation reaction and the flow of electrones to NADP under the phosphorylation conditions in the chloroplasts, and their effect on the O2 exchange is not the same in different types of photophosphorylation. It is supposed that the effect of IAA on the photophosphorylation is connected with H292 metabolism in chloroplasts and with catalase and peroxidase functions.

  7. Variable Neural Adaptive Robust Control: A Switched System Approach

    SciTech Connect

    Lian, Jianming; Hu, Jianghai; Zak, Stanislaw H.

    2015-05-01

    Variable neural adaptive robust control strategies are proposed for the output tracking control of a class of multi-input multi-output uncertain systems. The controllers incorporate a variable-structure radial basis function (RBF) network as the self-organizing approximator for unknown system dynamics. The variable-structure RBF network solves the problem of structure determination associated with fixed-structure RBF networks. It can determine the network structure on-line dynamically by adding or removing radial basis functions according to the tracking performance. The structure variation is taken into account in the stability analysis of the closed-loop system using a switched system approach with the aid of the piecewise quadratic Lyapunov function. The performance of the proposed variable neural adaptive robust controllers is illustrated with simulations.

  8. Adaptive Wing Camber Optimization: A Periodic Perturbation Approach

    NASA Technical Reports Server (NTRS)

    Espana, Martin; Gilyard, Glenn

    1994-01-01

    Available redundancy among aircraft control surfaces allows for effective wing camber modifications. As shown in the past, this fact can be used to improve aircraft performance. To date, however, algorithm developments for in-flight camber optimization have been limited. This paper presents a perturbational approach for cruise optimization through in-flight camber adaptation. The method uses, as a performance index, an indirect measurement of the instantaneous net thrust. As such, the actual performance improvement comes from the integrated effects of airframe and engine. The algorithm, whose design and robustness properties are discussed, is demonstrated on the NASA Dryden B-720 flight simulator.

  9. Parallel, grid-adaptive approaches for relativistic hydro and magnetohydrodynamics

    NASA Astrophysics Data System (ADS)

    Keppens, R.; Meliani, Z.; van Marle, A. J.; Delmont, P.; Vlasis, A.; van der Holst, B.

    2012-02-01

    Relativistic hydro and magnetohydrodynamics provide continuum fluid descriptions for gas and plasma dynamics throughout the visible universe. We present an overview of state-of-the-art modeling in special relativistic regimes, targeting strong shock-dominated flows with speeds approaching the speed of light. Significant progress in its numerical modeling emerged in the last two decades, and we highlight specifically the need for grid-adaptive, shock-capturing treatments found in several contemporary codes in active use and development. Our discussion highlights one such code, MPI-AMRVAC (Message-Passing Interface-Adaptive Mesh Refinement Versatile Advection Code), but includes generic strategies for allowing massively parallel, block-tree adaptive simulations in any dimensionality. We provide implementation details reflecting the underlying data structures as used in MPI-AMRVAC. Parallelization strategies and scaling efficiencies are discussed for representative applications, along with guidelines for data formats suitable for parallel I/O. Refinement strategies available in MPI-AMRVAC are presented, which cover error estimators in use in many modern AMR frameworks. A test suite for relativistic hydro and magnetohydrodynamics is provided, chosen to cover all aspects encountered in high-resolution, shock-governed astrophysical applications. This test suite provides ample examples highlighting the advantages of AMR in relativistic flow problems.

  10. The IAA Cosmic Study 'Protecting the Environment of Celestial Bodies'

    NASA Astrophysics Data System (ADS)

    Rettberg, Petra; Hofmann, Mahulena; Williamson, Mark

    The study group tasked with producing this International Academy of Astronautics (IAA) `Cosmic Study' on Protecting the Environment of Celestial Bodies was formed under the aus-pices of IAA Commission V (Space Policy, Law Economy). The members of the international, multidisciplinary team assembled to undertake the Study accept, as a premise, the Planetary Protection Policy guidelines developed by COSPAR, which differentiate the degree of protec-tion according to the type of space activity and the celestial body under investigation (such that fly-by missions have less stringent requirements than lander missions, while Mars is `better protected' than the Moon). However, this Study goes deliberately beyond the interpretation of `Planetary Protection' as a set of methods for protecting the planets from biological con-tamination and extends consideration to the geophysical, industrial and cultural realms. The Study concludes that, from the perspective of current and future activities in outer space, present measures aimed at protecting the space environment are insufficient. Deficiencies in-clude a lack of suitable in-situ methods of chemical and biological detection and the absence of a systematic record of radioactive contaminants. Other issues identified by the Study include an insufficient legal framework, a shortage of effective economic tools and a lack of political will to address these concerns. It is expected that new detection methods under development, and the resultant increase in microbiological knowledge of the planetary surfaces, will lead to changes in the COSPAR planetary protection guidelines and bioburden limits. It is important, however, that any new approaches should not hamper future exploration and exploitation of celestial bodies more than absolutely necessary. The Study addresses the need to find a balance between protection and freedom of action. From a legal perspective, the Study concludes that a general consensus on protection of the

  11. Block-adaptive quantum mechanics: an adaptive divide-and-conquer approach to interactive quantum chemistry.

    PubMed

    Bosson, Maël; Grudinin, Sergei; Redon, Stephane

    2013-03-01

    We present a novel Block-Adaptive Quantum Mechanics (BAQM) approach to interactive quantum chemistry. Although quantum chemistry models are known to be computationally demanding, we achieve interactive rates by focusing computational resources on the most active parts of the system. BAQM is based on a divide-and-conquer technique and constrains some nucleus positions and some electronic degrees of freedom on the fly to simplify the simulation. As a result, each time step may be performed significantly faster, which in turn may accelerate attraction to the neighboring local minima. By applying our approach to the nonself-consistent Atom Superposition and Electron Delocalization Molecular Orbital theory, we demonstrate interactive rates and efficient virtual prototyping for systems containing more than a thousand of atoms on a standard desktop computer.

  12. The Formative Method for Adapting Psychotherapy (FMAP): A community-based developmental approach to culturally adapting therapy

    PubMed Central

    Hwang, Wei-Chin

    2010-01-01

    How do we culturally adapt psychotherapy for ethnic minorities? Although there has been growing interest in doing so, few therapy adaptation frameworks have been developed. The majority of these frameworks take a top-down theoretical approach to adapting psychotherapy. The purpose of this paper is to introduce a community-based developmental approach to modifying psychotherapy for ethnic minorities. The Formative Method for Adapting Psychotherapy (FMAP) is a bottom-up approach that involves collaborating with consumers to generate and support ideas for therapy adaptation. It involves 5-phases that target developing, testing, and reformulating therapy modifications. These phases include: (a) generating knowledge and collaborating with stakeholders (b) integrating generated information with theory and empirical and clinical knowledge, (c) reviewing the initial culturally adapted clinical intervention with stakeholders and revising the culturally adapted intervention, (d) testing the culturally adapted intervention, and (e) finalizing the culturally adapted intervention. Application of the FMAP is illustrated using examples from a study adapting psychotherapy for Chinese Americans, but can also be readily applied to modify therapy for other ethnic groups. PMID:20625458

  13. IAA multilingual space dictionary, current status and future prospects

    NASA Astrophysics Data System (ADS)

    Yoshimitsu, Tetsuo; McKenna-Lawlor, Susan; Candel, Danielle; Ninomiya, Keiken; Contant, Jean-Michel

    2015-12-01

    Terminology is a key issue for a better understanding among people using various languages. Since 1986, when the International Academy of Astronautics (IAA) multilingual terminology database committee on astronautics was formed, the committee and its successor IAA study groups on the IAA multilingual space dictionary have made a continuous effort to construct a multilingual dictionary database on astronautical terms. In 2002, the dictionary was computerized using a database server and some recent internet technologies. The database is accessible from all over the world via the internet. You can search for terms at your home and office using a web browser installed on the computer with an internet connection. Since then, the number of terms and languages included in the database has increased. The current version includes about 3500 terms in 22 languages. The flexibility of the database enables the addition and the revision of new terms without much effort. The computerization has also demonstrated another possibility to utilize the database. When total of four paper books about the multilingual space terminology were published on the 50th anniversary of IAA in 2010, one of the lexicon books was edited by a computer program which accessed to the database. In this paper, the authors present the current status of the IAA multilingual database as well as the future possibilities on the utilization of the database.

  14. Extreme Sea Levels and Approaches to Adaptation in Germany

    NASA Astrophysics Data System (ADS)

    Weisse, R.; Kappenberg, J.; Sothmann, J.

    2014-12-01

    Germany's coastal areas are exposed to extra-tropical storms and related marine hazards such as wind waves and storm surges. About 50% of the coast is below 5 m NN and considerable parts are protected by an almost continuous dike line. Rising mean and extreme sea levels provide substantial threat. In this presentation we briefly review the present situation. Storm related sea level changes are characterized by pronounced inter-annual and decadal variability but do not show a long-term trend over the last century. Mean sea level has increased over the past about 100-150 years at a rate roughly comparable to global mean sea level rise. As a consequence extreme sea levels have increased in the area as increasing mean sea level shifts the baseline for storm surges and wind waves towards higher values. Different approaches for adaptation are investigated in a number ongoing research projects. Some case studies for potential adaptation and challenges are presented. Examples range from detailed analyses of retreat and accommodation strategies to multi-purpose strategies such as concepts for sustainable development of tidal estuaries.

  15. Salt stress adaptation of Bacillus subtilis: a physiological proteomics approach.

    PubMed

    Höper, Dirk; Bernhardt, Jörg; Hecker, Michael

    2006-03-01

    The adaptation to osmotic stress is crucial for growth and survival of Bacillus subtilis in its natural ecosystem. Dual channel imaging and warping of 2-D protein gels were used to visualize global changes in the protein synthesis pattern of cells in response to osmotic stress (6% NaCl). Many vegetative enzymes were repressed in response to salt stress and derepressed after resumption of growth. The enzymes catalyzing the metabolic steps from glucose to 2-oxoglutarate, however, were almost constantly synthesized during salt stress despite the growth arrest. This indicates an enhanced need for the proline precursor glutamate. The synthesis of enzymes involved in sulfate assimilation and in the formation of Fe-S clusters was also induced, suggesting an enhanced need for the formation or repair of Fe-S clusters in response to salt stress. One of the most obvious changes in the protein synthesis profile can be followed by the very strong induction of the SigB regulon. Furthermore, members of the SigW regulon and of the PerR regulon, indicating oxidative stress after salt challenge, were also induced. This proteomic approach provides an overview of cell adaptation to an osmotic upshift in B. subtilis visualizing the most dramatic changes in the protein synthesis pattern.

  16. Adaptive Neuro-fuzzy approach in friction identification

    NASA Astrophysics Data System (ADS)

    Zaiyad Muda @ Ismail, Muhammad

    2016-05-01

    Friction is known to affect the performance of motion control system, especially in terms of its accuracy. Therefore, a number of techniques or methods have been explored and implemented to alleviate the effects of friction. In this project, the Artificial Intelligent (AI) approach is used to model the friction which will be then used to compensate the friction. The Adaptive Neuro-Fuzzy Inference System (ANFIS) is chosen among several other AI methods because of its reliability and capabilities of solving complex computation. ANFIS is a hybrid AI-paradigm that combines the best features of neural network and fuzzy logic. This AI method (ANFIS) is effective for nonlinear system identification and compensation and thus, being used in this project.

  17. [Spanish adaptation of Hobfoll's Strategic Approach to Coping Scale (SACS)].

    PubMed

    Pedrero Pérez, Eduardo J; Santed Germán, Miguel A; Pérez García, Ana M

    2012-01-01

    The present research adapted the Strategic Approach to Coping Scale (SACS), developed by Hobfoll and colleagues, to the Spanish population. SACS is an instrument derived from Hobfoll's Conservation of Resources Theory, which emphasises the contribution of social factors to coping processes. This instrument assesses coping strategies in 9-subscales, organised in three dimensions: orientation to the problem (active/passive), use of social resources (prosocial/antisocial), and orientation to others involved (direct/indirect). The Spanish version, administered to a non-clinical sample (N= 767), found 7-subscales structured in prosocial/antisocial, active/passive and reflexive/intuitive dimensions, with adequate reliability and construct validity. To conclude, the Spanish SACS is a potentially useful and reliable instrument for research and clinical purposes, mainly in areas in which social components need to be explicitly considered.

  18. Adapting to Uncertainty: Comparing Methodological Approaches to Climate Adaptation and Mitigation Policy

    NASA Astrophysics Data System (ADS)

    Huda, J.; Kauneckis, D. L.

    2013-12-01

    Climate change adaptation represents a number of unique policy-making challenges. Foremost among these is dealing with the range of future climate impacts to a wide scope of inter-related natural systems, their interaction with social and economic systems, and uncertainty resulting from the variety of downscaled climate model scenarios and climate science projections. These cascades of uncertainty have led to a number of new approaches as well as a reexamination of traditional methods for evaluating risk and uncertainty in policy-making. Policy makers are required to make decisions and formulate policy irrespective of the level of uncertainty involved and while a debate continues regarding the level of scientific certainty required in order to make a decision, incremental change in the climate policy continues at multiple governance levels. This project conducts a comparative analysis of the range of methodological approaches that are evolving to address uncertainty in climate change policy. It defines 'methodologies' to include a variety of quantitative and qualitative approaches involving both top-down and bottom-up policy processes that attempt to enable policymakers to synthesize climate information into the policy process. The analysis examines methodological approaches to decision-making in climate policy based on criteria such as sources of policy choice information, sectors to which the methodology has been applied, sources from which climate projections were derived, quantitative and qualitative methods used to deal with uncertainty, and the benefits and limitations of each. A typology is developed to better categorize the variety of approaches and methods, examine the scope of policy activities they are best suited for, and highlight areas for future research and development.

  19. Analyzing Hedges in Verbal Communication: An Adaptation-Based Approach

    ERIC Educational Resources Information Center

    Wang, Yuling

    2010-01-01

    Based on Adaptation Theory, the article analyzes the production process of hedges. The procedure consists of the continuous making of choices in linguistic forms and communicative strategies. These choices are made just for adaptation to the contextual correlates. Besides, the adaptation process is dynamic, intentional and bidirectional.

  20. Implementation and use of a highly available and innovative IaaS solution: the Cloud Area Padovana

    NASA Astrophysics Data System (ADS)

    Aiftimiei, C.; Andreetto, P.; Bertocco, S.; Biasotto, M.; Dal Pra, S.; Costa, F.; Crescente, A.; Dorigo, A.; Fantinel, S.; Fanzago, F.; Frizziero, E.; Gulmini, M.; Michelotto, M.; Sgaravatto, M.; Traldi, S.; Venaruzzo, M.; Verlato, M.; Zangrando, L.

    2015-12-01

    While in the business world the cloud paradigm is typically implemented purchasing resources and services from third party providers (e.g. Amazon), in the scientific environment there's usually the need of on-premises IaaS infrastructures which allow efficient usage of the hardware distributed among (and owned by) different scientific administrative domains. In addition, the requirement of open source adoption has led to the choice of products like OpenStack by many organizations. We describe a use case of the Italian National Institute for Nuclear Physics (INFN) which resulted in the implementation of a unique cloud service, called ’Cloud Area Padovana’, which encompasses resources spread over two different sites: the INFN Legnaro National Laboratories and the INFN Padova division. We describe how this IaaS has been implemented, which technologies have been adopted and how services have been configured in high-availability (HA) mode. We also discuss how identity and authorization management were implemented, adopting a widely accepted standard architecture based on SAML2 and OpenID: by leveraging the versatility of those standards the integration with authentication federations like IDEM was implemented. We also discuss some other innovative developments, such as a pluggable scheduler, implemented as an extension of the native OpenStack scheduler, which allows the allocation of resources according to a fair-share based model and which provides a persistent queuing mechanism for handling user requests that can not be immediately served. Tools, technologies, procedures used to install, configure, monitor, operate this cloud service are also discussed. Finally we present some examples that show how this IaaS infrastructure is being used.

  1. Division IAA Football Players and Risk Factors for Metabolic Syndrome

    ERIC Educational Resources Information Center

    Repovich, Wendy E. S.; Babcock, Garth J.

    2012-01-01

    The purpose of this study was to determine if body composition and blood pressure (BP), two markers for Metabolic Syndrome (MetS), were correlated in college football players. Height, weight, BMI, systolic (SBP) and Diastolic (DBP) blood pressure and body composition (three measures) were assessed in a Division IAA football team (N = 55). Data…

  2. Demonstrations at School Level of the Effects of IAA

    ERIC Educational Resources Information Center

    Falk, Peter

    1973-01-01

    Describes demonstrations suitable for secondary school biology classes relating to the effects of the hormone IAA on plant growth. Demonstrations illustrate how hormone treatments affect stem elongation, callus formation, inhibition of axillary buds, stimulation of secondary growth and initiation of adventitious root development, root elongation,…

  3. Diversity of Stability, Localization, Interaction and Control of Downstream Gene Activity in the Maize Aux/IAA Protein Family

    PubMed Central

    Ludwig, Yvonne; Berendzen, Kenneth W.; Xu, Changzheng; Piepho, Hans-Peter; Hochholdinger, Frank

    2014-01-01

    AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) proteins are central regulators of auxin signal transduction. They control many aspects of plant development, share a conserved domain structure and are localized in the nucleus. In the present study, five maize Aux/IAA proteins (ZmIAA2, ZmIAA11, ZmIAA15, ZmIAA20 and ZmIAA33) representing the evolutionary, phylogenetic and expression diversity of this gene family were characterized. Subcellular localization studies revealed that ZmIAA2, ZmIAA11 and ZmIAA15 are confined to the nucleus while ZmIAA20 and ZmIAA33 are localized in both the nucleus and the cytoplasm. Introduction of specific point mutations in the degron sequence (VGWPPV) of domain II by substituting the first proline by serine or the second proline by leucine stabilized the Aux/IAA proteins. While protein half-life times between ∼11 min (ZmIAA2) to ∼120 min (ZmIAA15) were observed in wild-type proteins, the mutated forms of all five proteins were almost as stable as GFP control proteins. Moreover, all five maize Aux/IAA proteins repressed downstream gene expression in luciferase assays to different degrees. In addition, bimolecular fluorescence complementation (BiFC) analyses demonstrated interaction of all five Aux/IAA proteins with RUM1 (ROOTLESS WITH UNDETECTABLE MERISTEM 1, ZmIAA10) while only ZmIAA15 and ZmIAA33 interacted with the RUM1 paralog RUL1 (RUM-LIKE 1, ZmIAA29). Moreover, ZmIAA11, ZmIAA15 ZmIAA33 displayed homotypic interaction. Hence, despite their conserved domain structure, maize Aux/IAA proteins display a significant variability in their molecular characteristics which is likely associated with the wide spectrum of their developmental functions. PMID:25203637

  4. Mutation in domain II of IAA1 confers diverse auxin-related phenotypes and represses auxin-activated expression of Aux/IAA genes in steroid regulator-inducible system.

    PubMed

    Park, Jin-Young; Kim, Hye-Joung; Kim, Jungmook

    2002-12-01

    Most of Aux/IAA genes are rapidly induced by auxin. The Aux/IAA proteins are short-lived nuclear proteins sharing the four conserved domains. Domain II is critical for rapid degradation of Aux/IAA proteins. Among these gene family members, IAA1 is one of the earliest auxin-inducible genes. We used a steroid hormone-inducible system to reveal putative roles and downstream signaling of IAA1 in auxin response. Arabidopsis transgenic plants were generated expressing fusion protein of IAA1 (IAA1-GR) or IAA1 with a mutation in domain II (iaa1-GR) and the glucocorticoid hormone-binding domain (GR). IAA1-GR transgenic plants did not exhibit any discernable phenotypic differences by DEX treatment that allows nuclear translocation of the fusion protein. In contrast, diverse auxin-related physiological processes including gravitropism and phototropism were impaired by DEX treatment in roots, hypocotyls, stems, and leaves in iaa1-GR transgenic plants. Auxin induction of seven Aux/IAA mRNAs including IAA1 itself was repressed by DEX treatment, suggesting that IAA1 functions in the nucleus by mediating auxin response and might act as a negative feedback regulator for the expression of Aux/IAA genes including IAA1 itself. Auxin induction of Aux/IAA genes in the presence of cycloheximide can be repressed by DEX treatment, showing that the repression of transcription of the Aux/IAAs by the iaa1 mutant protein is primary. Wild-type IAA1-GR could not suppress auxin induction of IAA1 and IAA2. These results indicate that inhibition of auxin-activated transcription of Aux/IAA genes by the iaa1 mutant protein might be responsible for alteration of various auxin responses.

  5. Expression of wild-type PtrIAA14.1, a poplar Aux/IAA gene causes morphological changes in Arabidopsis

    PubMed Central

    Liu, Shanda; Hu, Qingnan; Luo, Sha; Li, Qianqian; Yang, Xiyu; Wang, Xianling; Wang, Shucai

    2015-01-01

    Aux/IAA proteins are transcriptional repressors that control auxin signaling by interacting with auxin response factors (ARFs). So far all of the identified Aux/IAA mutants with auxin-related phenotypes in Arabidopsis and rice (Oryza sativa) are dominant gain-of-function mutants, with mutations in Domain II that affected stability of the corresponding Aux/IAA proteins. On the other hand, morphological changes were observed in knock-down mutants of Aux/IAA genes in tomato (Solanum lycopersicum), suggesting that functions of Aux/IAA proteins may be specific for certain plant species. We report here the characterization of PtrIAA14.1, a poplar (Populus trichocarpa) homolog of IAA7. Bioinformatics analysis showed that PtrIAA14.1 is a classic Aux/IAA protein. It contains four conserved domains with the repressor motif in Domain I, the degron in Domain II, and the conserved amino acid signatures for protein–protein interactions in Domain III and Domain IV. Protoplast transfection assays showed that PtrIAA14.1 is localized in nucleus. It is unable in the presence of auxin, and it represses auxin response reporter gene expression. Expression of wild-type PtrIAA14.1 in Arabidopsis resulted in auxin-related phenotypes including down-curling leaves, semi-draft with increased number of branches, and greatly reduced fertility, but expression of the Arabidopsis Aux/IAA genes tested remain largely unchanged in the transgenic plants. Protein–protein interaction assays in yeast and protoplasts showed that PtrIAA14.1 interacted with ARF5, but not other ARFs. Consistent with this observation, vascular patterning was altered in the transgenic plants, and the expression of AtHB8 (Arabidopsis thaliana homeobox gene 8) was reduced in transgenic plants. PMID:26082787

  6. Discrete adaptive zone light elements (DAZLE): a new approach to adaptive imaging

    NASA Astrophysics Data System (ADS)

    Kellogg, Robert L.; Escuti, Michael J.

    2007-09-01

    New advances in Liquid Crystal Spatial Light Modulators (LCSLM) offer opportunities for large adaptive optics in the midwave infrared spectrum. A light focusing adaptive imaging system, using the zero-order diffraction state of a polarizer-free liquid crystal polarization grating modulator to create millions of high transmittance apertures, is envisioned in a system called DAZLE (Discrete Adaptive Zone Light Elements). DAZLE adaptively selects large sets of LCSLM apertures using the principles of coded masks, embodied in a hybrid Discrete Fresnel Zone Plate (DFZP) design. Issues of system architecture, including factors of LCSLM aperture pattern and adaptive control, image resolution and focal plane array (FPA) matching, and trade-offs between filter bandwidths, background photon noise, and chromatic aberration are discussed.

  7. Approach for Using Learner Satisfaction to Evaluate the Learning Adaptation Policy

    ERIC Educational Resources Information Center

    Jeghal, Adil; Oughdir, Lahcen; Tairi, Hamid; Radouane, Abdelhay

    2016-01-01

    The learning adaptation is a very important phase in a learning situation in human learning environments. This paper presents the authors' approach used to evaluate the effectiveness of learning adaptive systems. This approach is based on the analysis of learner satisfaction notices collected by a questionnaire on a learning situation; to analyze…

  8. An adaptive demodulation approach for bearing fault detection based on adaptive wavelet filtering and spectral subtraction

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Tang, Baoping; Liu, Ziran; Chen, Rengxiang

    2016-02-01

    Fault diagnosis of rolling element bearings is important for improving mechanical system reliability and performance. Vibration signals contain a wealth of complex information useful for state monitoring and fault diagnosis. However, any fault-related impulses in the original signal are often severely tainted by various noises and the interfering vibrations caused by other machine elements. Narrow-band amplitude demodulation has been an effective technique to detect bearing faults by identifying bearing fault characteristic frequencies. To achieve this, the key step is to remove the corrupting noise and interference, and to enhance the weak signatures of the bearing fault. In this paper, a new method based on adaptive wavelet filtering and spectral subtraction is proposed for fault diagnosis in bearings. First, to eliminate the frequency associated with interfering vibrations, the vibration signal is bandpass filtered with a Morlet wavelet filter whose parameters (i.e. center frequency and bandwidth) are selected in separate steps. An alternative and efficient method of determining the center frequency is proposed that utilizes the statistical information contained in the production functions (PFs). The bandwidth parameter is optimized using a local ‘greedy’ scheme along with Shannon wavelet entropy criterion. Then, to further reduce the residual in-band noise in the filtered signal, a spectral subtraction procedure is elaborated after wavelet filtering. Instead of resorting to a reference signal as in the majority of papers in the literature, the new method estimates the power spectral density of the in-band noise from the associated PF. The effectiveness of the proposed method is validated using simulated data, test rig data, and vibration data recorded from the transmission system of a helicopter. The experimental results and comparisons with other methods indicate that the proposed method is an effective approach to detecting the fault-related impulses

  9. Non-adaptive and adaptive hybrid approaches for enhancing water quality management

    NASA Astrophysics Data System (ADS)

    Kalwij, Ineke M.; Peralta, Richard C.

    2008-09-01

    SummaryUsing optimization to help solve groundwater management problems cost-effectively is becoming increasingly important. Hybrid optimization approaches, that combine two or more optimization algorithms, will become valuable and common tools for addressing complex nonlinear hydrologic problems. Hybrid heuristic optimizers have capabilities far beyond those of a simple genetic algorithm (SGA), and are continuously improving. SGAs having only parent selection, crossover, and mutation are inefficient and rarely used for optimizing contaminant transport management. Even an advanced genetic algorithm (AGA) that includes elitism (to emphasize using the best strategies as parents) and healing (to help assure optimal strategy feasibility) is undesirably inefficient. Much more efficient than an AGA is the presented hybrid (AGCT), which adds comprehensive tabu search (TS) features to an AGA. TS mechanisms (TS probability, tabu list size, search coarseness and solution space size, and a TS threshold value) force the optimizer to search portions of the solution space that yield superior pumping strategies, and to avoid reproducing similar or inferior strategies. An AGCT characteristic is that TS control parameters are unchanging during optimization. However, TS parameter values that are ideal for optimization commencement can be undesirable when nearing assumed global optimality. The second presented hybrid, termed global converger (GC), is significantly better than the AGCT. GC includes AGCT plus feedback-driven auto-adaptive control that dynamically changes TS parameters during run-time. Before comparing AGCT and GC, we empirically derived scaled dimensionless TS control parameter guidelines by evaluating 50 sets of parameter values for a hypothetical optimization problem. For the hypothetical area, AGCT optimized both well locations and pumping rates. The parameters are useful starting values because using trial-and-error to identify an ideal combination of control

  10. The Lunar Farside Radio Lab Study of the IAA

    NASA Astrophysics Data System (ADS)

    Maccone, Claudio

    2002-01-01

    The "Lunar Farside Radio Lab" Study of the IAA, started in 1998 by late French astronomer Jean Heidmann (1923-2000), underwent substantial extensions and revisions since its coordination was taken up by this author. These modifications can be summarized as follows: 1) The goal of the Study was enlarged so as to encompass the whole of radio astronomy, rather 2) It was stressed that, from the Lunar Farside, one can detect radio frequencies lower than 15 3) Lunar Farside Crater Saha, initially selected by Heidmann to host a radiotelescope, was 4) Four different scenarios were envisaged for the relevant space mission, dubbed RadioMoon: Finally, legal protection of Daedalus from radio-pollution was sought, initially by virtue of the IISL. The "Lunar Farside Radio Lab" Study of the IAA should be completed by October 2003 with a number of distinguished contributions. Its present status and prospects are explained and motivated in this paper.

  11. An examination of the handheld adapter approach for measuring hand-transmitted vibration exposure

    PubMed Central

    Xu, Xueyan S.; Dong, Ren G.; Welcome, Daniel E.; Warren, Christopher; McDowell, Thomas W.

    2015-01-01

    The use of a handheld adapter equipped with a tri-axial accelerometer is the most convenient and efficient approach for measuring vibration exposure at the hand-tool interface, especially when the adapter is incorporated into a miniature handheld or wrist-strapped dosimeter. To help optimize the adapter approach, the specific aims of this study are to identify and understand the major sources and mechanisms of measurement errors and uncertainties associated with using these adapters, and to explore their improvements. Five representative adapter models were selected and used in the experiment. Five human subjects served as operators in the experiment on a hand-arm vibration test system. The results of this study confirm that many of the handheld adapters can produce substantial overestimations of vibration exposure, and measurement errors can significantly vary with tool, adapter model, mounting position, mounting orientation, and subject. Major problems with this approach include unavoidable influence of the hand dynamic motion on the adapter, unstable attachment, insufficient attachment contact force, and inappropriate adapter structure. However, the results of this study also suggest that measurement errors can be substantially reduced if the design and use of an adapter can be systematically optimized toward minimizing the combined effects of the identified factors. Some potential methods for improving the design and use of the adapters are also proposed and discussed. PMID:26744580

  12. Hierarchy-Direction Selective Approach for Locally Adaptive Sparse Grids

    SciTech Connect

    Stoyanov, Miroslav K

    2013-09-01

    We consider the problem of multidimensional adaptive hierarchical interpolation. We use sparse grids points and functions that are induced from a one dimensional hierarchical rule via tensor products. The classical locally adaptive sparse grid algorithm uses an isotropic refinement from the coarser to the denser levels of the hierarchy. However, the multidimensional hierarchy provides a more complex structure that allows for various anisotropic and hierarchy selective refinement techniques. We consider the more advanced refinement techniques and apply them to a number of simple test functions chosen to demonstrate the various advantages and disadvantages of each method. While there is no refinement scheme that is optimal for all functions, the fully adaptive family-direction-selective technique is usually more stable and requires fewer samples.

  13. Classification of EEG for Affect Recognition: An Adaptive Approach

    NASA Astrophysics Data System (ADS)

    Alzoubi, Omar; Calvo, Rafael A.; Stevens, Ronald H.

    Research on affective computing is growing rapidly and new applications are being developed more frequently. They use information about the affective/mental states of users to adapt their interfaces or add new functionalities. Face activity, voice, text physiology and other information about the user are used as input to affect recognition modules, which are built as classification algorithms. Brain EEG signals have rarely been used to build such classifiers due to the lack of a clear theoretical framework. We present here an evaluation of three different classification techniques and their adaptive variations of a 10-class emotion recognition experiment. Our results show that affect recognition from EEG signals might be possible and an adaptive algorithm improves the performance of the classification task.

  14. Taking a Broad Approach to Public Health Program Adaptation: Adapting a Family-Based Diabetes Education Program

    ERIC Educational Resources Information Center

    Reinschmidt, Kerstin M.; Teufel-Shone, Nicolette I.; Bradford, Gail; Drummond, Rebecca L.; Torres, Emma; Redondo, Floribella; Elenes, Jo Jean; Sanders, Alicia; Gastelum, Sylvia; Moore-Monroy, Martha; Barajas, Salvador; Fernandez, Lourdes; Alvidrez, Rosy; de Zapien, Jill Guernsey; Staten, Lisa K.

    2010-01-01

    Diabetes health disparities among Hispanic populations have been countered with federally funded health promotion and disease prevention programs. Dissemination has focused on program adaptation to local cultural contexts for greater acceptability and sustainability. Taking a broader approach and drawing on our experience in Mexican American…

  15. Combined phylogenetic and genomic approaches for the high-throughput study of microbial habitat adaptation

    PubMed Central

    Zaneveld, Jesse RR.; Parfrey, Laura Wegener; Van Treuren, Will; Lozupone, Catherine; Clemente, Jose C.; Knights, Dan; Stombaugh, Jesse; Kuczynski, Justin; Knight, Rob

    2011-01-01

    High-throughput sequencing technologies provide new opportunities to address longstanding questions about habitat adaptation in microbial organisms. How have microbes managed to adapt to such a wide range of environments, and what genomic features allow for such adaptation? We review recent large-scale studies of habitat adaptation, with emphasis on those that utilize phylogenetic techniques. On the basis of current trends, we summarize methodological challenges faced by investigators, and the tools, techniques, and analytical approaches available to overcome them. Phylogenetic approaches and detailed information about each environmental sample will be critical as the ability to collect genome sequences continues to expand. PMID:21872475

  16. A Monte Carlo Approach for Adaptive Testing with Content Constraints

    ERIC Educational Resources Information Center

    Belov, Dmitry I.; Armstrong, Ronald D.; Weissman, Alexander

    2008-01-01

    This article presents a new algorithm for computerized adaptive testing (CAT) when content constraints are present. The algorithm is based on shadow CAT methodology to meet content constraints but applies Monte Carlo methods and provides the following advantages over shadow CAT: (a) lower maximum item exposure rates, (b) higher utilization of the…

  17. Dissociating Conflict Adaptation from Feature Integration: A Multiple Regression Approach

    ERIC Educational Resources Information Center

    Notebaert, Wim; Verguts, Tom

    2007-01-01

    Congruency effects are typically smaller after incongruent than after congruent trials. One explanation is in terms of higher levels of cognitive control after detection of conflict (conflict adaptation; e.g., M. M. Botvinick, T. S. Braver, D. M. Barch, C. S. Carter, & J. D. Cohen, 2001). An alternative explanation for these results is based on…

  18. Adaptive E-Learning Environments: Research Dimensions and Technological Approaches

    ERIC Educational Resources Information Center

    Di Bitonto, Pierpaolo; Roselli, Teresa; Rossano, Veronica; Sinatra, Maria

    2013-01-01

    One of the most closely investigated topics in e-learning research has always been the effectiveness of adaptive learning environments. The technological evolutions that have dramatically changed the educational world in the last six decades have allowed ever more advanced and smarter solutions to be proposed. The focus of this paper is to depict…

  19. The Canadian approach to the settlement and adaptation of immigrants.

    PubMed

    1986-01-01

    Canada has been the host to over 400,000 refugees since World War II. The settlement and adaptation process is supported by the federal government and by the majority of provincial governments. Under the national and regional Employment and Immigration Commission CEIC) settlement organizations the major programs administered to effect the adaptation of newcomers are: 1) the Adjustment Assistance Program, 2) the Immigrant Settlement and Adaptation Program, 3) the Language/Skill Training Program, and 4) the Employment Services Program. Ontario, the recipient of more than 1/2 the newcomers that arrive in Canada each year, pursues active programs in the reception of newcomers through their Welcome House Program which offers a wide range of reception services to the newcomers. The employment and unemployment experiences of refugees is very much influenced by the prevailing labor market conditions, the refugees' proficiency in the country's official languages, the amount of sympathy evoked by the media reports on the plight of refugees, the availability of people of the same ethnic origin already well settled in the country, and the adaptability of the refugees themselves. The vast majority of refugee groups that came to Canada during the last 1/4 century seem to have adjusted well economically, despite having had difficulty in entering the occupations they intended to join. It is calculated that an average of $6607 per arrival is needed to cover the CEIC program costs of 1983-1984.

  20. Alternative mechanism for the evaluation of indole-3-acetic acid (IAA) production by Azospirillum brasilense strains and its effects on the germination and growth of maize seedlings.

    PubMed

    Masciarelli, Oscar; Urbani, Lucia; Reinoso, Herminda; Luna, Virginia

    2013-10-01

    We evaluated the production of indole-3-acetic acid (IAA) by Azospirillum brasilense strains in vitro (cell culture supernatants) and in vivo (stems and roots of maize seedlings) to clarify the role of this phytohormone as a signaling and effector molecule in the symbiotic interaction between maize and A. brasilense. The three strains all showed IAA production when cultured in NFb medium supplemented with 100 μg/ml L-tryptophan. The level of IAA production was 41.5 μg/ml for Yu62, 12.9 μg/ml for Az39, and 0.15 μg/ml for ipdC-. The release of IAA into culture medium by the bacteria appeared to be the main activator of the early growth promotion observed in the inoculated maize seedlings. The application of supernatants with different IAA contents caused significant differences in the seedling growth. This observation provides the basis for novel technological tools for effective quality control procedures on inoculants. The approach described can be incorporated into different inoculation methods, including line sowing, downspout, and foliar techniques, and increase the sustainability of symbiotic plant-bacteria systems.

  1. An approach to fabrication of large adaptive optics mirrors

    NASA Astrophysics Data System (ADS)

    Schwartz, Eric; Rey, Justin; Blaszak, David; Cavaco, Jeffrey

    2014-07-01

    For more than two decades, Northrop Grumman Xinetics has been the principal supplier of small deformable mirrors that enable adaptive optical (AO) systems for the ground-based astronomical telescope community. With today's drive toward extremely large aperture systems, and the desire of telescope designers to include adaptive optics in the main optical path of the telescope, Xinetics has recognized the need for large active mirrors with the requisite bandwidth and actuator stoke. Presented in this paper is the proposed use of Northrop Grumman Xinetics' large, ultra-lightweight Silicon Carbide substrates with surface parallel actuation of sufficient spatial density and bandwidth to meet the requirements of tomorrow's AO systems, while reducing complexity and cost.

  2. Assessing confidence in management adaptation approaches for climate-sensitive ecosystems

    NASA Astrophysics Data System (ADS)

    West, J. M.; Julius, S. H.; Weaver, C. P.

    2012-03-01

    A number of options are available for adapting ecosystem management to improve resilience in the face of climatic changes. However, uncertainty exists as to the effectiveness of these options. A report prepared for the US Climate Change Science Program reviewed adaptation options for a range of federally managed systems in the United States. The report included a qualitative uncertainty analysis of conceptual approaches to adaptation derived from the review. The approaches included reducing anthropogenic stressors, protecting key ecosystem features, maintaining representation, replicating, restoring, identifying refugia and relocating organisms. The results showed that the expert teams had the greatest scientific confidence in adaptation options that reduce anthropogenic stresses. Confidence in other approaches was lower because of gaps in understanding of ecosystem function, climate change impacts on ecosystems, and management effectiveness. This letter discusses insights gained from the confidence exercise and proposes strategies for improving future assessments of confidence for management adaptations to climate change.

  3. Genome-Wide Analysis and Characterization of Aux/IAA Family Genes in Brassica rapa.

    PubMed

    Paul, Parameswari; Dhandapani, Vignesh; Rameneni, Jana Jeevan; Li, Xiaonan; Sivanandhan, Ganesan; Choi, Su Ryun; Pang, Wenxing; Im, Subin; Lim, Yong Pyo

    2016-01-01

    Auxins are the key players in plant growth development involving leaf formation, phototropism, root, fruit and embryo development. Auxin/Indole-3-Acetic Acid (Aux/IAA) are early auxin response genes noted as transcriptional repressors in plant auxin signaling. However, many studies focus on Aux/ARF gene families and much less is known about the Aux/IAA gene family in Brassica rapa (B. rapa). Here we performed a comprehensive genome-wide analysis and identified 55 Aux/IAA genes in B. rapa using four conserved motifs of Aux/IAA family (PF02309). Chromosomal mapping of the B. rapa Aux/IAA (BrIAA) genes facilitated understanding cluster rearrangement of the crucifer building blocks in the genome. Phylogenetic analysis of BrIAA with Arabidopsis thaliana, Oryza sativa and Zea mays identified 51 sister pairs including 15 same species (BrIAA-BrIAA) and 36 cross species (BrIAA-AtIAA) IAA genes. Among the 55 BrIAA genes, expression of 43 and 45 genes were verified using Genebank B. rapa ESTs and in home developed microarray data from mature leaves of Chiifu and RcBr lines. Despite their huge morphological difference, tissue specific expression analysis of BrIAA genes between the parental lines Chiifu and RcBr showed that the genes followed a similar pattern of expression during leaf development and a different pattern during bud, flower and siliqua development stages. The response of the BrIAA genes to abiotic and auxin stress at different time intervals revealed their involvement in stress response. Single Nucleotide Polymorphisms between IAA genes of reference genome Chiifu and RcBr were focused and identified. Our study examines the scope of conservation and divergence of Aux/IAA genes and their structures in B. rapa. Analyzing the expression and structural variation between two parental lines will significantly contribute to functional genomics of Brassica crops and we belive our study would provide a foundation in understanding the Aux/IAA genes in B. rapa.

  4. Genome-Wide Analysis and Characterization of Aux/IAA Family Genes in Brassica rapa.

    PubMed

    Paul, Parameswari; Dhandapani, Vignesh; Rameneni, Jana Jeevan; Li, Xiaonan; Sivanandhan, Ganesan; Choi, Su Ryun; Pang, Wenxing; Im, Subin; Lim, Yong Pyo

    2016-01-01

    Auxins are the key players in plant growth development involving leaf formation, phototropism, root, fruit and embryo development. Auxin/Indole-3-Acetic Acid (Aux/IAA) are early auxin response genes noted as transcriptional repressors in plant auxin signaling. However, many studies focus on Aux/ARF gene families and much less is known about the Aux/IAA gene family in Brassica rapa (B. rapa). Here we performed a comprehensive genome-wide analysis and identified 55 Aux/IAA genes in B. rapa using four conserved motifs of Aux/IAA family (PF02309). Chromosomal mapping of the B. rapa Aux/IAA (BrIAA) genes facilitated understanding cluster rearrangement of the crucifer building blocks in the genome. Phylogenetic analysis of BrIAA with Arabidopsis thaliana, Oryza sativa and Zea mays identified 51 sister pairs including 15 same species (BrIAA-BrIAA) and 36 cross species (BrIAA-AtIAA) IAA genes. Among the 55 BrIAA genes, expression of 43 and 45 genes were verified using Genebank B. rapa ESTs and in home developed microarray data from mature leaves of Chiifu and RcBr lines. Despite their huge morphological difference, tissue specific expression analysis of BrIAA genes between the parental lines Chiifu and RcBr showed that the genes followed a similar pattern of expression during leaf development and a different pattern during bud, flower and siliqua development stages. The response of the BrIAA genes to abiotic and auxin stress at different time intervals revealed their involvement in stress response. Single Nucleotide Polymorphisms between IAA genes of reference genome Chiifu and RcBr were focused and identified. Our study examines the scope of conservation and divergence of Aux/IAA genes and their structures in B. rapa. Analyzing the expression and structural variation between two parental lines will significantly contribute to functional genomics of Brassica crops and we belive our study would provide a foundation in understanding the Aux/IAA genes in B. rapa. PMID

  5. A regional approach to climate adaptation in the Nile Basin

    NASA Astrophysics Data System (ADS)

    Butts, Michael B.; Buontempo, Carlo; Lørup, Jens K.; Williams, Karina; Mathison, Camilla; Jessen, Oluf Z.; Riegels, Niels D.; Glennie, Paul; McSweeney, Carol; Wilson, Mark; Jones, Richard; Seid, Abdulkarim H.

    2016-10-01

    The Nile Basin is one of the most important shared basins in Africa. Managing and developing the water resources within the basin must not only address different water uses but also the trade-off between developments upstream and water use downstream, often between different countries. Furthermore, decision-makers in the region need to evaluate and implement climate adaptation measures. Previous work has shown that the Nile flows can be highly sensitive to climate change and that there is considerable uncertainty in climate projections in the region with no clear consensus as to the direction of change. Modelling current and future changes in river runoff must address a number of challenges; including the large size of the basin, the relative scarcity of data, and the corresponding dramatic variety of climatic conditions and diversity in hydrological characteristics. In this paper, we present a methodology, to support climate adaptation on a regional scale, for assessing climate change impacts and adaptation potential for floods, droughts and water scarcity within the basin.

  6. The adaptive significance of adult neurogenesis: an integrative approach

    PubMed Central

    Konefal, Sarah; Elliot, Mick; Crespi, Bernard

    2013-01-01

    Adult neurogenesis in mammals is predominantly restricted to two brain regions, the dentate gyrus (DG) of the hippocampus and the olfactory bulb (OB), suggesting that these two brain regions uniquely share functions that mediate its adaptive significance. Benefits of adult neurogenesis across these two regions appear to converge on increased neuronal and structural plasticity that subserves coding of novel, complex, and fine-grained information, usually with contextual components that include spatial positioning. By contrast, costs of adult neurogenesis appear to center on potential for dysregulation resulting in higher risk of brain cancer or psychological dysfunctions, but such costs have yet to be quantified directly. The three main hypotheses for the proximate functions and adaptive significance of adult neurogenesis, pattern separation, memory consolidation, and olfactory spatial, are not mutually exclusive and can be reconciled into a simple general model amenable to targeted experimental and comparative tests. Comparative analysis of brain region sizes across two major social-ecological groups of primates, gregarious (mainly diurnal haplorhines, visually-oriented, and in large social groups) and solitary (mainly noctural, territorial, and highly reliant on olfaction, as in most rodents) suggest that solitary species, but not gregarious species, show positive associations of population densities and home range sizes with sizes of both the hippocampus and OB, implicating their functions in social-territorial systems mediated by olfactory cues. Integrated analyses of the adaptive significance of adult neurogenesis will benefit from experimental studies motivated and structured by ecologically and socially relevant selective contexts. PMID:23882188

  7. Effect of IAA produced by Klebsiella oxytoca Rs-5 on cotton growth under salt stress.

    PubMed

    Liu, Yan; Shi, Zaiqiang; Yao, Lixia; Yue, Haitao; Li, Hui; Li, Chun

    2013-01-01

    Klebsiella oxytoca Rs-5 isolated with ACC (1-aminocyclopropane-1-carboxylate) deaminase activity as the sole nitrogen source could obviously promote cotton seedling growth under salt stress and produce phytohormone indole-3-acetic acid (IAA). The amount of IAA produced by the strain Rs-5 was measured, and the effect of IAA on cotton growth under salt stress was studied. Different treatments were set to treat cotton seeds with fermentation broth containing strain Rs-5 (FB), strain Rs-5, fermentation broth with bacteria removed (FB-NB), fermentation broth without bacteria or IAA (FB-NB-NI) and single IAA solutions (SI) according to the IAA concentration after strain Rs-5 culturing of 48, 72 and 120 h. The germination rate, dry weight, plant height, root length and malondialdehyde (MDA), proline and endogenous IAA content in roots were determined. The results showed that both IAA produced by strain Rs-5 and the strain were effective in promoting cotton growth under salt stress. The growth and ability to resist salt stress of cotton seedlings were increased with the enhancement of IAA concentration. The treatment of FB containing bacteria and IAA at 120 h obtained the best state of cotton growth, when the IAA content was the highest in the fermentation broth (42.14 μg·L(-1)). The germination rate, dry weight, plant height and root length were increased by 29.4%, 24.3%, 27.2% and 27.2% , respectively, compared to the saline control. The strain Rs-5 and/or IAA could obviously reduce the MDA and proline content and increase the endogenous IAA content in cotton seedlings. However, the efficacy of other components in the fermentation broth was inconspicuous.

  8. The Application of the Monte Carlo Approach to Cognitive Diagnostic Computerized Adaptive Testing With Content Constraints

    ERIC Educational Resources Information Center

    Mao, Xiuzhen; Xin, Tao

    2013-01-01

    The Monte Carlo approach which has previously been implemented in traditional computerized adaptive testing (CAT) is applied here to cognitive diagnostic CAT to test the ability of this approach to address multiple content constraints. The performance of the Monte Carlo approach is compared with the performance of the modified maximum global…

  9. Evidence of an Adaptive Level Grading Practice through a Causal Approach.

    ERIC Educational Resources Information Center

    Gallini, Joan

    1982-01-01

    The adaptation level theory in grading implies that students select major programs whose grading practices are realistic with their ability. A causal approach using a system of multiple equations was used to investigate this theory. The results lent support to occurrence of the adaptive grading practice. (Author/CM)

  10. An Adaptive Approach to Managing Knowledge Development in a Project-Based Learning Environment

    ERIC Educational Resources Information Center

    Tilchin, Oleg; Kittany, Mohamed

    2016-01-01

    In this paper we propose an adaptive approach to managing the development of students' knowledge in the comprehensive project-based learning (PBL) environment. Subject study is realized by two-stage PBL. It shapes adaptive knowledge management (KM) process and promotes the correct balance between personalized and collaborative learning. The…

  11. Making CORBA objects persistent: The object database adapter approach

    SciTech Connect

    Reverbel, F.C.R.

    1997-05-01

    In spite of its remarkable successes in promoting standards for distributed object systems, the Object Management Group (OMG) has not yet settled the issue of object persistence in the Object Request Broker (ORB) environment. The Common Object Request Broker Architecture (CORBA) specification briefly mentions an Object-Oriented Database Adapter that makes objects stored in an object-oriented database accessible through the ORB. This idea is pursued in the Appendix B of the ODMG standard, which identifies a number of issues involved in using an Object Database Management System (ODBMS) in a CORBA environment, and proposes an Object Database Adapter (ODA) to realize the integration of the ORB with the ODBMS. This paper discusses the design and implementation of an ODA that integrates an ORB and an ODBMS with C++ bindings. For the author`s purposes, an ODBMS is a system with programming interfaces. It may be a pure object-oriented DBMS (an OODBMS), or a combination of a relational DBMS and an object-relational mapper.

  12. [Molecular genetic bases of adaptation processes and approaches to their analysis].

    PubMed

    Salmenkova, E A

    2013-01-01

    Great interest in studying the molecular genetic bases of the adaptation processes is explained by their importance in understanding evolutionary changes, in the development ofintraspecific and interspecific genetic diversity, and in the creation of approaches and programs for maintaining and restoring the population. The article examines the sources and conditions for generating adaptive genetic variability and contribution of neutral and adaptive genetic variability to the population structure of the species; methods for identifying the adaptive genetic variability on the genome level are also described. Considerable attention is paid to the potential of new technologies of genome analysis, including next-generation sequencing and some accompanying methods. In conclusion, the important role of the joint use of genomics and proteomics approaches in understanding the molecular genetic bases of adaptation is emphasized.

  13. An Evidence-Based Public Health Approach to Climate Change Adaptation

    PubMed Central

    Eidson, Millicent; Tlumak, Jennifer E.; Raab, Kristin K.; Luber, George

    2014-01-01

    Background: Public health is committed to evidence-based practice, yet there has been minimal discussion of how to apply an evidence-based practice framework to climate change adaptation. Objectives: Our goal was to review the literature on evidence-based public health (EBPH), to determine whether it can be applied to climate change adaptation, and to consider how emphasizing evidence-based practice may influence research and practice decisions related to public health adaptation to climate change. Methods: We conducted a substantive review of EBPH, identified a consensus EBPH framework, and modified it to support an EBPH approach to climate change adaptation. We applied the framework to an example and considered implications for stakeholders. Discussion: A modified EBPH framework can accommodate the wide range of exposures, outcomes, and modes of inquiry associated with climate change adaptation and the variety of settings in which adaptation activities will be pursued. Several factors currently limit application of the framework, including a lack of higher-level evidence of intervention efficacy and a lack of guidelines for reporting climate change health impact projections. To enhance the evidence base, there must be increased attention to designing, evaluating, and reporting adaptation interventions; standardized health impact projection reporting; and increased attention to knowledge translation. This approach has implications for funders, researchers, journal editors, practitioners, and policy makers. Conclusions: The current approach to EBPH can, with modifications, support climate change adaptation activities, but there is little evidence regarding interventions and knowledge translation, and guidelines for projecting health impacts are lacking. Realizing the goal of an evidence-based approach will require systematic, coordinated efforts among various stakeholders. Citation: Hess JJ, Eidson M, Tlumak JE, Raab KK, Luber G. 2014. An evidence-based public

  14. IAA transport in corn roots includes the root cap

    SciTech Connect

    Hasenstein, K.H. )

    1989-04-01

    In earlier reports we concluded that auxin is the growth regulator that controls gravicurvature in roots and that the redistribution of auxin occurs within the root cap. Since other reports did not detect auxin in the root cap, we attempted to confirm the IAA does move through the cap. Agar blocks containing {sup 3}H-IAA were applied to the cut surface of 5 mm long apical segments of primary roots of corn (mo17xB73). After 30 to 120 min radioactivity (RA) of the cap and root tissue was determined. While segments suspended in water-saturated air accumulated very little RA in the cap, application of 0.5 {mu}1 of dist. water to the cap (=controls) increased RA of the cap dramatically. Application to the cap of 0.5 {mu}1 of sorbitol or the Ca{sup 2+} chelator EGTA reduced cap RA to 46% and 70% respectively compared to water, without affecting uptake. Control root segments gravireacted faster than non-treated or osmoticum or EGTA treated segments. The data indicate that both the degree of hydration and calcium control the amount of auxin moving through the cap.

  15. Genome-Wide Analysis and Characterization of Aux/IAA Family Genes in Brassica rapa

    PubMed Central

    Rameneni, Jana Jeevan; Li, Xiaonan; Sivanandhan, Ganesan; Choi, Su Ryun; Pang, Wenxing; Im, Subin; Lim, Yong Pyo

    2016-01-01

    Auxins are the key players in plant growth development involving leaf formation, phototropism, root, fruit and embryo development. Auxin/Indole-3-Acetic Acid (Aux/IAA) are early auxin response genes noted as transcriptional repressors in plant auxin signaling. However, many studies focus on Aux/ARF gene families and much less is known about the Aux/IAA gene family in Brassica rapa (B. rapa). Here we performed a comprehensive genome-wide analysis and identified 55 Aux/IAA genes in B. rapa using four conserved motifs of Aux/IAA family (PF02309). Chromosomal mapping of the B. rapa Aux/IAA (BrIAA) genes facilitated understanding cluster rearrangement of the crucifer building blocks in the genome. Phylogenetic analysis of BrIAA with Arabidopsis thaliana, Oryza sativa and Zea mays identified 51 sister pairs including 15 same species (BrIAA—BrIAA) and 36 cross species (BrIAA—AtIAA) IAA genes. Among the 55 BrIAA genes, expression of 43 and 45 genes were verified using Genebank B. rapa ESTs and in home developed microarray data from mature leaves of Chiifu and RcBr lines. Despite their huge morphological difference, tissue specific expression analysis of BrIAA genes between the parental lines Chiifu and RcBr showed that the genes followed a similar pattern of expression during leaf development and a different pattern during bud, flower and siliqua development stages. The response of the BrIAA genes to abiotic and auxin stress at different time intervals revealed their involvement in stress response. Single Nucleotide Polymorphisms between IAA genes of reference genome Chiifu and RcBr were focused and identified. Our study examines the scope of conservation and divergence of Aux/IAA genes and their structures in B. rapa. Analyzing the expression and structural variation between two parental lines will significantly contribute to functional genomics of Brassica crops and we belive our study would provide a foundation in understanding the Aux/IAA genes in B. rapa. PMID

  16. Adaptation to floods in future climate: a practical approach

    NASA Astrophysics Data System (ADS)

    Doroszkiewicz, Joanna; Romanowicz, Renata; Radon, Radoslaw; Hisdal, Hege

    2016-04-01

    In this study some aspects of the application of the 1D hydraulic model are discussed with a focus on its suitability for flood adaptation under future climate conditions. The Biała Tarnowska catchment is used as a case study. A 1D hydraulic model is developed for the evaluation of inundation extent and risk maps in future climatic conditions. We analyse the following flood indices: (i) extent of inundation area; (ii) depth of water on flooded land; (iii) the flood wave duration; (iv) the volume of a flood wave over the threshold value. In this study we derive a model cross-section geometry following the results of primary research based on a 500-year flood inundation extent. We compare two methods of localisation of cross-sections from the point of view of their suitability to the derivation of the most precise inundation outlines. The aim is to specify embankment heights along the river channel that would protect the river valley in the most vulnerable locations under future climatic conditions. We present an experimental design for scenario analysis studies and uncertainty reduction options for future climate projections obtained from the EUROCORDEX project. Acknowledgements: This work was supported by the project CHIHE (Climate Change Impact on Hydrological Extremes), carried out in the Institute of Geophysics Polish Academy of Sciences, funded by Norway Grants (contract No. Pol-Nor/196243/80/2013). The hydro-meteorological observations were provided by the Institute of Meteorology and Water Management (IMGW), Poland.

  17. Developmental Structuralist Approach to the Classification of Adaptive and Pathologic Personality Organizations: Infancy and Early Childhood.

    ERIC Educational Resources Information Center

    Greenspan, Stanley I.; Lourie, Reginald S.

    This paper applies a developmental structuralist approach to the classification of adaptive and pathologic personality organizations and behavior in infancy and early childhood, and it discusses implications of this approach for preventive intervention. In general, as development proceeds, the structural capacity of the developing infant and child…

  18. Adaptation of a weighted regression approach to evaluate water quality trends in anestuary

    EPA Science Inventory

    To improve the description of long-term changes in water quality, a weighted regression approach developed to describe trends in pollutant transport in rivers was adapted to analyze a long-term water quality dataset from Tampa Bay, Florida. The weighted regression approach allows...

  19. Adaptation of a Weighted Regression Approach to Evaluate Water Quality Trends in an Estuary

    EPA Science Inventory

    To improve the description of long-term changes in water quality, we adapted a weighted regression approach to analyze a long-term water quality dataset from Tampa Bay, Florida. The weighted regression approach, originally developed to resolve pollutant transport trends in rivers...

  20. Adaptive Role Playing Games: An Immersive Approach for Problem Based Learning

    ERIC Educational Resources Information Center

    Sancho, Pilar; Moreno-Ger, Pablo; Fuentes-Fernandez, Ruben; Fernandez-Manjon, Baltasar

    2009-01-01

    In this paper we present a general framework, called NUCLEO, for the application of socio-constructive educational approaches in higher education. The underlying pedagogical approach relies on an adaptation model in order to improve group dynamics, as this has been identified as one of the key features in the success of collaborative learning…

  1. A continuum of approaches toward developing culturally focused prevention interventions: from adaptation to grounding.

    PubMed

    Okamoto, Scott K; Kulis, Stephen; Marsiglia, Flavio F; Steiker, Lori K Holleran; Dustman, Patricia

    2014-04-01

    The purpose of this article is to describe a conceptual model of methods used to develop culturally focused interventions. We describe a continuum of approaches ranging from non-adapted/surface-structure adapted programs to culturally grounded programs, and present recent examples of interventions resulting from the application of each of these approaches. The model has implications for categorizing culturally focused prevention efforts more accurately, and for gauging the time, resources, and level of community engagement necessary to develop programs using each of the different methods. The model also has implications for funding decisions related to the development and evaluation of programs, and for planning of participatory research approaches with community members.

  2. Risk assessment of nanomaterials and nanoproducts - adaptation of traditional approaches

    NASA Astrophysics Data System (ADS)

    Jahnel, J.; Fleischer, T.; Seitz, S. B.

    2013-04-01

    Different approaches have been adopted for assessing the potential risks of conventional chemicals and products for human health. In general, the traditional paradigm is a toxicological-driven chemical-by-chemical approach, focusing on single toxic endpoints. Scope and responsibilities for the development and implementation of a risk assessment concept vary across sectors and areas and depends on the specific regulatory environment and the specific protection goals. Thus, risk assessment implication is a complex task based not only on science based knowledge but also on the regulatory context involving different parties and stakeholders. Questions have been raised whether standard paradigms for conventional chemicals would be applicable and adequate for new materials, products and applications of nanotechnology. Most scientists and stakeholders assume that current standard methods are in principle applicable to nanomaterials, but specific aspects require further development. The paper presents additional technical improvements like the complementary use of the life cycle methodology and the support of risk-based classification systems. But also aspects improving the utility of risk assessment with regard to societal impacts on risk governance are discussed.

  3. Farms adaptation to changes in flood risk: a management approach

    NASA Astrophysics Data System (ADS)

    Pivot, Jean-Marc; Martin, Philippe

    2002-10-01

    Creating flood expansion areas e.g. for the protection of urban areas from flooding involves a localised increase in risk which may require farmers to be compensated for crop damage or other losses. With this in mind, the paper sets out the approach used to study the problem and gives results obtained from a survey of farms liable to flooding in central France. The approach is based on a study of decisions made by farmers in situations of uncertainty, using the concept of 'model of action'. The results show that damage caused to farming areas by flooding should be considered both at field level and at farm level. The damage caused to the field depends on the flood itself, the fixed characteristics of the field, and the plant species cultivated. However, the losses to the farm taken as a whole can differ considerably from those for the flooded field, due to 'knock-on' effects on farm operations which depend on the internal organization, the availability of production resources, and the farmer's objectives, both for the farm as a whole and for its individual enterprises. Three main strategies regarding possible flood events were identified. Reasons for choosing one of these include the way the farmer perceives the risk and the size of the area liable to flooding. Finally, the formalisation of farm system management in the face of uncertainty, especially due to flooding, enables compensation to be calculated for farmers whose land is affected by the creation of flood expansion areas.

  4. Role of IAA-Oxidase in Abscission Control in Cotton 123

    PubMed Central

    Schwertner, Harvey A.; Morgan, Page W.

    1966-01-01

    The potential role of indoleactic acid (IAA)-oxidase as an in vivo abscission regulating system in the cotton (Gossypium hirsutum L.) cotyledonary explant was investigated. Phenols (usually monophenols), which are cofactors of cotton IAA-oxidase in vitro, accelerated abscission. Phenols (usually orthodihydroxyphenols), which inhibit cotton IAA-oxidase in vitro, inhibited abscission. Inhibition or stimulation of abscission was accomplished by phenols both with and without IAA. Results were similar when treatments were applied as lanolin pastes to the cut petiole ends or as solutions in which explants were submerged. An abscission accelerating phenol stimulated the decarboxylation of IAA-1-14C by explants and an abscission inhibiting phenol inhibited the decarboxylation of IAA-1-14C. The mechanism of abscission regulation by the phenolic compounds was concluded to involve auxin destruction via IAA-oxidase. In addition to the direct relationship of this study to abscission, the results support the more general hypothesis that IAA-oxidase acts in vivo to regulate auxin levels. PMID:16656432

  5. Identification and expression analysis of primary auxin-responsive Aux/IAA gene family in cucumber (Cucumis sativus).

    PubMed

    Gan, Defang; Zhuang, Dan; Ding, Fei; Yu, Zhenzhou; Zhao, Yang

    2013-12-01

    Aux/IAA is an important gene family involved in many aspects of growth and development. Aux/IAA proteins are short-lived nuclear proteins that are induced primarily by various phytohormones. In this study, 29 Aux/IAA family genes (CsIAA01-CsIAA29) were identified and characterized in cucumber, including gene structures, phylogenetic relationships, conserved protein motifs and chromosomal locations. These genes show distinct organizational patterns of their putative motifs. The distributions of the genes vary: except for five CsIAA genes in cucumber that were not located, seven CsIAA genes were found on scaffold, while the other 17 CsIAA genes were distributed on seven other chromosomes. Based on a phylogenetic analysis of the Aux/IAA protein sequences from cucumber, Arabidopsis and other plants, the Aux/IAA genes in cucumber were categorized into seven subfamilies. To investigate whether the expression of CsIAA genes is associated with auxin induction, their transcript levels were monitored in seedlings treated with IAA (indole-3-acetic acid), and their expression patterns were analysed by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). The results showed that 11/29 CsIAA genes were expressed in leaves whether treated with IAA or not and the time course of processing and compared with the control, five CsIAA genes showed low expression only after 60 min treatment with IAA, while 11 genes showed no expression. These results provide useful information for further functional analysis of Aux/IAA gene family in cucumber.

  6. Land-based approach to evaluate sustainable land management and adaptive capacity of ecosystems/lands

    NASA Astrophysics Data System (ADS)

    Kust, German; Andreeva, Olga

    2015-04-01

    A number of new concepts and paradigms appeared during last decades, such as sustainable land management (SLM), climate change (CC) adaptation, environmental services, ecosystem health, and others. All of these initiatives still not having the common scientific platform although some agreements in terminology were reached, schemes of links and feedback loops created, and some models developed. Nevertheless, in spite of all these scientific achievements, the land related issues are still not in the focus of CC adaptation and mitigation. The last did not grow much beyond the "greenhouse gases" (GHG) concept, which makes land degradation as the "forgotten side of climate change" The possible decision to integrate concepts of climate and desertification/land degradation could be consideration of the "GHG" approach providing global solution, and "land" approach providing local solution covering other "locally manifesting" issues of global importance (biodiversity conservation, food security, disasters and risks, etc.) to serve as a central concept among those. SLM concept is a land-based approach, which includes the concepts of both ecosystem-based approach (EbA) and community-based approach (CbA). SLM can serve as in integral CC adaptation strategy, being based on the statement "the more healthy and resilient the system is, the less vulnerable and more adaptive it will be to any external changes and forces, including climate" The biggest scientific issue is the methods to evaluate the SLM and results of the SLM investments. We suggest using the approach based on the understanding of the balance or equilibrium of the land and nature components as the major sign of the sustainable system. Prom this point of view it is easier to understand the state of the ecosystem stress, size of the "health", range of adaptive capacity, drivers of degradation and SLM nature, as well as the extended land use, and the concept of environmental land management as the improved SLM approach

  7. Genome-wide analysis of Aux/IAA and ARF gene families in Populus trichocarpa

    SciTech Connect

    Kalluri, Udaya C; DiFazio, Stephen P; Brunner, A.; Tuskan, Gerald A

    2007-01-01

    Auxin/Indole-3-Acetic Acid (Aux/IAA) and Auxin Response Factor (ARF) transcription factors are key regulators of auxin responses in plants. A total of 35 Aux/IAA and 39 ARF genes were identified in the Populus genome. Comparative phylogenetic analysis revealed that the subgroups PoptrARF2, 6, 9 and 16 and PoptrIAA3, 16, 27 and 29 have differentially expanded in Populus relative to Arabidopsis. Activator ARFs were found to be two fold-overrepresented in the Populus genome. PoptrIAA and PoptrARF gene families appear to have expanded due to high segmental and low tandem duplication events. Furthermore, expression studies showed that genes in the expanded PoptrIAA3 subgroup display differential expression. The gene-family analysis reported here will be useful in conducting future functional genomics studies to understand how the molecular roles of these large gene families translate into a diversity of biologically meaningful auxin effects.

  8. Cross-cultural adaptation of instruments assessing breastfeeding determinants: a multi-step approach

    PubMed Central

    2014-01-01

    Background Cross-cultural adaptation is a necessary process to effectively use existing instruments in other cultural and language settings. The process of cross-culturally adapting, including translation, of existing instruments is considered a critical set to establishing a meaningful instrument for use in another setting. Using a multi-step approach is considered best practice in achieving cultural and semantic equivalence of the adapted version. We aimed to ensure the content validity of our instruments in the cultural context of KwaZulu-Natal, South Africa. Methods The Iowa Infant Feeding Attitudes Scale, Breastfeeding Self-Efficacy Scale-Short Form and additional items comprise our consolidated instrument, which was cross-culturally adapted utilizing a multi-step approach during August 2012. Cross-cultural adaptation was achieved through steps to maintain content validity and attain semantic equivalence in the target version. Specifically, Lynn’s recommendation to apply an item-level content validity index score was followed. The revised instrument was translated and back-translated. To ensure semantic equivalence, Brislin’s back-translation approach was utilized followed by the committee review to address any discrepancies that emerged from translation. Results Our consolidated instrument was adapted to be culturally relevant and translated to yield more reliable and valid results for use in our larger research study to measure infant feeding determinants effectively in our target cultural context. Conclusions Undertaking rigorous steps to effectively ensure cross-cultural adaptation increases our confidence that the conclusions we make based on our self-report instrument(s) will be stronger. In this way, our aim to achieve strong cross-cultural adaptation of our consolidated instruments was achieved while also providing a clear framework for other researchers choosing to utilize existing instruments for work in other cultural, geographic and population

  9. The Colorado Climate Preparedness Project: A Systematic Approach to Assessing Efforts Supporting State-Level Adaptation

    NASA Astrophysics Data System (ADS)

    Klein, R.; Gordon, E.

    2010-12-01

    Scholars and policy analysts often contend that an effective climate adaptation strategy must entail "mainstreaming," or incorporating responses to possible climate impacts into existing planning and management decision frameworks. Such an approach, however, makes it difficult to assess the degree to which decisionmaking entities are engaging in adaptive activities that may or may not be explicitly framed around a changing climate. For example, a drought management plan may not explicitly address climate change, but the activities and strategies outlined in it may reduce vulnerabilities posed by a variable and changing climate. Consequently, to generate a strategic climate adaptation plan requires identifying the entire suite of activities that are implicitly linked to climate and may affect adaptive capacity within the system. Here we outline a novel, two-pronged approach, leveraging social science methods, to understanding adaptation throughout state government in Colorado. First, we conducted a series of interviews with key actors in state and federal government agencies, non-governmental organizations, universities, and other entities engaged in state issues. The purpose of these interviews was to elicit information about current activities that may affect the state’s adaptive capacity and to identify future climate-related needs across the state. Second, we have developed an interactive database cataloging organizations, products, projects, and people actively engaged in adaptive planning and policymaking that are relevant to the state of Colorado. The database includes a wiki interface, helping create a dynamic component that will enable frequent updating as climate-relevant information emerges. The results of this project are intended to paint a clear picture of sectors and agencies with higher and lower levels of adaptation awareness and to provide a roadmap for the next gubernatorial administration to pursue a more sophisticated climate adaptation agenda

  10. Dioxygenase-encoding AtDAO1 gene controls IAA oxidation and homeostasis in Arabidopsis.

    PubMed

    Porco, Silvana; Pěnčík, Aleš; Rashed, Afaf; Voß, Ute; Casanova-Sáez, Rubén; Bishopp, Anthony; Golebiowska, Agata; Bhosale, Rahul; Swarup, Ranjan; Swarup, Kamal; Peňáková, Pavlína; Novák, Ondřej; Staswick, Paul; Hedden, Peter; Phillips, Andrew L; Vissenberg, Kris; Bennett, Malcolm J; Ljung, Karin

    2016-09-27

    Auxin represents a key signal in plants, regulating almost every aspect of their growth and development. Major breakthroughs have been made dissecting the molecular basis of auxin transport, perception, and response. In contrast, how plants control the metabolism and homeostasis of the major form of auxin in plants, indole-3-acetic acid (IAA), remains unclear. In this paper, we initially describe the function of the Arabidopsis thaliana gene DIOXYGENASE FOR AUXIN OXIDATION 1 (AtDAO1). Transcriptional and translational reporter lines revealed that AtDAO1 encodes a highly root-expressed, cytoplasmically localized IAA oxidase. Stable isotope-labeled IAA feeding studies of loss and gain of function AtDAO1 lines showed that this oxidase represents the major regulator of auxin degradation to 2-oxoindole-3-acetic acid (oxIAA) in Arabidopsis Surprisingly, AtDAO1 loss and gain of function lines exhibited relatively subtle auxin-related phenotypes, such as altered root hair length. Metabolite profiling of mutant lines revealed that disrupting AtDAO1 regulation resulted in major changes in steady-state levels of oxIAA and IAA conjugates but not IAA. Hence, IAA conjugation and catabolism seem to regulate auxin levels in Arabidopsis in a highly redundant manner. We observed that transcripts of AtDOA1 IAA oxidase and GH3 IAA-conjugating enzymes are auxin-inducible, providing a molecular basis for their observed functional redundancy. We conclude that the AtDAO1 gene plays a key role regulating auxin homeostasis in Arabidopsis, acting in concert with GH3 genes, to maintain auxin concentration at optimal levels for plant growth and development. PMID:27651491

  11. Dioxygenase-encoding AtDAO1 gene controls IAA oxidation and homeostasis in Arabidopsis

    PubMed Central

    Porco, Silvana; Pěnčík, Aleš; Rashed, Afaf; Voß, Ute; Casanova-Sáez, Rubén; Bishopp, Anthony; Golebiowska, Agata; Swarup, Ranjan; Swarup, Kamal; Peňáková, Pavlína; Novák, Ondřej; Staswick, Paul; Hedden, Peter; Phillips, Andrew L.; Vissenberg, Kris

    2016-01-01

    Auxin represents a key signal in plants, regulating almost every aspect of their growth and development. Major breakthroughs have been made dissecting the molecular basis of auxin transport, perception, and response. In contrast, how plants control the metabolism and homeostasis of the major form of auxin in plants, indole-3-acetic acid (IAA), remains unclear. In this paper, we initially describe the function of the Arabidopsis thaliana gene DIOXYGENASE FOR AUXIN OXIDATION 1 (AtDAO1). Transcriptional and translational reporter lines revealed that AtDAO1 encodes a highly root-expressed, cytoplasmically localized IAA oxidase. Stable isotope-labeled IAA feeding studies of loss and gain of function AtDAO1 lines showed that this oxidase represents the major regulator of auxin degradation to 2-oxoindole-3-acetic acid (oxIAA) in Arabidopsis. Surprisingly, AtDAO1 loss and gain of function lines exhibited relatively subtle auxin-related phenotypes, such as altered root hair length. Metabolite profiling of mutant lines revealed that disrupting AtDAO1 regulation resulted in major changes in steady-state levels of oxIAA and IAA conjugates but not IAA. Hence, IAA conjugation and catabolism seem to regulate auxin levels in Arabidopsis in a highly redundant manner. We observed that transcripts of AtDOA1 IAA oxidase and GH3 IAA-conjugating enzymes are auxin-inducible, providing a molecular basis for their observed functional redundancy. We conclude that the AtDAO1 gene plays a key role regulating auxin homeostasis in Arabidopsis, acting in concert with GH3 genes, to maintain auxin concentration at optimal levels for plant growth and development. PMID:27651491

  12. Using archaeogenomic and computational approaches to unravel the history of local adaptation in crops

    PubMed Central

    Allaby, Robin G.; Gutaker, Rafal; Clarke, Andrew C.; Pearson, Neil; Ware, Roselyn; Palmer, Sarah A.; Kitchen, James L.; Smith, Oliver

    2015-01-01

    Our understanding of the evolution of domestication has changed radically in the past 10 years, from a relatively simplistic rapid origin scenario to a protracted complex process in which plants adapted to the human environment. The adaptation of plants continued as the human environment changed with the expansion of agriculture from its centres of origin. Using archaeogenomics and computational models, we can observe genome evolution directly and understand how plants adapted to the human environment and the regional conditions to which agriculture expanded. We have applied various archaeogenomics approaches as exemplars to study local adaptation of barley to drought resistance at Qasr Ibrim, Egypt. We show the utility of DNA capture, ancient RNA, methylation patterns and DNA from charred remains of archaeobotanical samples from low latitudes where preservation conditions restrict ancient DNA research to within a Holocene timescale. The genomic level of analyses that is now possible, and the complexity of the evolutionary process of local adaptation means that plant studies are set to move to the genome level, and account for the interaction of genes under selection in systems-level approaches. This way we can understand how plants adapted during the expansion of agriculture across many latitudes with rapidity. PMID:25487329

  13. A User-Centered Approach to Adaptive Hypertext Based on an Information Relevance Model

    NASA Technical Reports Server (NTRS)

    Mathe, Nathalie; Chen, James

    1994-01-01

    Rapid and effective to information in large electronic documentation systems can be facilitated if information relevant in an individual user's content can be automatically supplied to this user. However most of this knowledge on contextual relevance is not found within the contents of documents, it is rather established incrementally by users during information access. We propose a new model for interactively learning contextual relevance during information retrieval, and incrementally adapting retrieved information to individual user profiles. The model, called a relevance network, records the relevance of references based on user feedback for specific queries and user profiles. It also generalizes such knowledge to later derive relevant references for similar queries and profiles. The relevance network lets users filter information by context of relevance. Compared to other approaches, it does not require any prior knowledge nor training. More importantly, our approach to adaptivity is user-centered. It facilitates acceptance and understanding by users by giving them shared control over the adaptation without disturbing their primary task. Users easily control when to adapt and when to use the adapted system. Lastly, the model is independent of the particular application used to access information, and supports sharing of adaptations among users.

  14. Rapid construction of multiple sgRNA vectors and knockout of the Arabidopsis IAA2 gene using the CRISPR/Cas9 genomic editing technology.

    PubMed

    Dingyuan, Liu; Ting, Qiu; Xiaohui, Ding; Miaomiao, Li; Muyuan, Zhu; Junhui, Wang

    2016-08-01

    IAA2 is a member of the Aux/IAA auxin responsive gene family in Arabidopsis thaliana. No iaa2 mutant has been reported until now, thus hindering its further mechanistic investigations. The normal genomic editing technology of CRISPR/Cas9 (Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9) uses only a single guide RNA (sgRNA) to target one site in a specific gene, and the gene knockout efficiency is not high. Instead, multiple sgRNAs can target multiple sites; therefore, the efficiency may be improved. In the present investigation, we used the golden-gate cloning strategy and two rounds of PCR reactions to combine three sgRNAs in the same entry vector. The final expression vector was obtained by LR reactions with the destination vector containing the Cas9 expression cassette. Four out of the six sgRNAs were effective, and we also obtained a lot of insertion and deletion mutations. Compared with one sgRNA approach, multiple sgRNAs displayed higher gene-knockout efficiency and produced more germ-line mutants. Thus, we established a more rapid and efficient method and generated five mutants for further studies of IAA2 functions.

  15. Rapid construction of multiple sgRNA vectors and knockout of the Arabidopsis IAA2 gene using the CRISPR/Cas9 genomic editing technology.

    PubMed

    Dingyuan, Liu; Ting, Qiu; Xiaohui, Ding; Miaomiao, Li; Muyuan, Zhu; Junhui, Wang

    2016-08-01

    IAA2 is a member of the Aux/IAA auxin responsive gene family in Arabidopsis thaliana. No iaa2 mutant has been reported until now, thus hindering its further mechanistic investigations. The normal genomic editing technology of CRISPR/Cas9 (Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9) uses only a single guide RNA (sgRNA) to target one site in a specific gene, and the gene knockout efficiency is not high. Instead, multiple sgRNAs can target multiple sites; therefore, the efficiency may be improved. In the present investigation, we used the golden-gate cloning strategy and two rounds of PCR reactions to combine three sgRNAs in the same entry vector. The final expression vector was obtained by LR reactions with the destination vector containing the Cas9 expression cassette. Four out of the six sgRNAs were effective, and we also obtained a lot of insertion and deletion mutations. Compared with one sgRNA approach, multiple sgRNAs displayed higher gene-knockout efficiency and produced more germ-line mutants. Thus, we established a more rapid and efficient method and generated five mutants for further studies of IAA2 functions. PMID:27531614

  16. Adapt

    NASA Astrophysics Data System (ADS)

    Bargatze, L. F.

    2015-12-01

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

  17. An enhanced adaptive management approach for remediation of legacy mercury in the South River.

    PubMed

    Foran, Christy M; Baker, Kelsie M; Grosso, Nancy R; Linkov, Igor

    2015-01-01

    Uncertainties about future conditions and the effects of chosen actions, as well as increasing resource scarcity, have been driving forces in the utilization of adaptive management strategies. However, many applications of adaptive management have been criticized for a number of shortcomings, including a limited ability to learn from actions and a lack of consideration of stakeholder objectives. To address these criticisms, we supplement existing adaptive management approaches with a decision-analytical approach that first informs the initial selection of management alternatives and then allows for periodic re-evaluation or phased implementation of management alternatives based on monitoring information and incorporation of stakeholder values. We describe the application of this enhanced adaptive management (EAM) framework to compare remedial alternatives for mercury in the South River, based on an understanding of the loading and behavior of mercury in the South River near Waynesboro, VA. The outcomes show that the ranking of remedial alternatives is influenced by uncertainty in the mercury loading model, by the relative importance placed on different criteria, and by cost estimates. The process itself demonstrates that a decision model can link project performance criteria, decision-maker preferences, environmental models, and short- and long-term monitoring information with management choices to help shape a remediation approach that provides useful information for adaptive, incremental implementation.

  18. Evaluating adaptive governance approaches to sustainable water management in north-west Thailand.

    PubMed

    Clark, Julian R A; Semmahasak, Chutiwalanch

    2013-04-01

    Adaptive governance is advanced as a potent means of addressing institutional fit of natural resource systems with prevailing modes of political-administrative management. Its advocates also argue that it enhances participatory and learning opportunities for stakeholders over time. Yet an increasing number of studies demonstrate real difficulties in implementing adaptive governance 'solutions'. This paper builds on these debates by examining the introduction of adaptive governance to water management in Chiang Mai province, north-west Thailand. The paper considers, first, the limitations of current water governance modes at the provincial scale, and the rationale for implementation of an adaptive approach. The new approach is then critically examined, with its initial performance and likely future success evaluated by (i) analysis of water stakeholders' opinions of its first year of operation; and (ii) comparison of its governance attributes against recent empirical accounts of implementation difficulty and failure of adaptive governance of natural resource management more generally. The analysis confirms the potentially significant role that the new approach can play in brokering and resolving the underlying differences in stakeholder representation and knowledge construction at the heart of the prevailing water governance modes in north-west Thailand.

  19. Shape anomaly detection under strong measurement noise: An analytical approach to adaptive thresholding

    NASA Astrophysics Data System (ADS)

    Krasichkov, Alexander S.; Grigoriev, Eugene B.; Bogachev, Mikhail I.; Nifontov, Eugene M.

    2015-10-01

    We suggest an analytical approach to the adaptive thresholding in a shape anomaly detection problem. We find an analytical expression for the distribution of the cosine similarity score between a reference shape and an observational shape hindered by strong measurement noise that depends solely on the noise level and is independent of the particular shape analyzed. The analytical treatment is also confirmed by computer simulations and shows nearly perfect agreement. Using this analytical solution, we suggest an improved shape anomaly detection approach based on adaptive thresholding. We validate the noise robustness of our approach using typical shapes of normal and pathological electrocardiogram cycles hindered by additive white noise. We show explicitly that under high noise levels our approach considerably outperforms the conventional tactic that does not take into account variations in the noise level.

  20. A Time-Critical Adaptive Approach for Visualizing Natural Scenes on Different Devices

    PubMed Central

    Dong, Tianyang; Liu, Siyuan; Xia, Jiajia; Fan, Jing; Zhang, Ling

    2015-01-01

    To automatically adapt to various hardware and software environments on different devices, this paper presents a time-critical adaptive approach for visualizing natural scenes. In this method, a simplified expression of a tree model is used for different devices. The best rendering scheme is intelligently selected to generate a particular scene by estimating the rendering time of trees based on their visual importance. Therefore, this approach can ensure the reality of natural scenes while maintaining a constant frame rate for their interactive display. To verify its effectiveness and flexibility, this method is applied in different devices, such as a desktop computer, laptop, iPad and smart phone. Applications show that the method proposed in this paper can not only adapt to devices with different computing abilities and system resources very well but can also achieve rather good visual realism and a constant frame rate for natural scenes. PMID:25723177

  1. A Monte Carlo Approach to the Design, Assembly, and Evaluation of Multistage Adaptive Tests

    ERIC Educational Resources Information Center

    Belov, Dmitry I.; Armstrong, Ronald D.

    2008-01-01

    This article presents an application of Monte Carlo methods for developing and assembling multistage adaptive tests (MSTs). A major advantage of the Monte Carlo assembly over other approaches (e.g., integer programming or enumerative heuristics) is that it provides a uniform sampling from all MSTs (or MST paths) available from a given item pool.…

  2. Complexity Thinking in PE: Game-Centred Approaches, Games as Complex Adaptive Systems, and Ecological Values

    ERIC Educational Resources Information Center

    Storey, Brian; Butler, Joy

    2013-01-01

    Background: This article draws on the literature relating to game-centred approaches (GCAs), such as Teaching Games for Understanding, and dynamical systems views of motor learning to demonstrate a convergence of ideas around games as complex adaptive learning systems. This convergence is organized under the title "complexity thinking"…

  3. An Enhanced Approach to Combine Item Response Theory with Cognitive Diagnosis in Adaptive Testing

    ERIC Educational Resources Information Center

    Wang, Chun; Zheng, Chanjin; Chang, Hua-Hua

    2014-01-01

    Computerized adaptive testing offers the possibility of gaining information on both the overall ability and cognitive profile in a single assessment administration. Some algorithms aiming for these dual purposes have been proposed, including the shadow test approach, the dual information method (DIM), and the constraint weighted method. The…

  4. Development of an Assistance Environment for Tutors Based on a Co-Adaptive Design Approach

    ERIC Educational Resources Information Center

    Lavoue, Elise; George, Sebastien; Prevot, Patrick

    2012-01-01

    In this article, we present a co-adaptive design approach named TE-Cap (Tutoring Experience Capitalisation) that we applied for the development of an assistance environment for tutors. Since tasks assigned to tutors in educational contexts are not well defined, we are developing an environment which responds to needs which are not precisely…

  5. Three Authentic Curriculum-Integration Approaches to Bird Adaptations That Incorporate Technology and Thinking Skills

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Barrera, Manuel T., III

    2008-01-01

    Integration of subject areas with technology and thinking skills is a way to help teachers cope with today's overloaded curriculum and to help students see the connectedness of different curriculum areas. This study compares three authentic approaches to teaching a science unit on bird adaptations for habitat that integrate thinking skills and…

  6. A Hybrid Acoustic and Pronunciation Model Adaptation Approach for Non-native Speech Recognition

    NASA Astrophysics Data System (ADS)

    Oh, Yoo Rhee; Kim, Hong Kook

    In this paper, we propose a hybrid model adaptation approach in which pronunciation and acoustic models are adapted by incorporating the pronunciation and acoustic variabilities of non-native speech in order to improve the performance of non-native automatic speech recognition (ASR). Specifically, the proposed hybrid model adaptation can be performed at either the state-tying or triphone-modeling level, depending at which acoustic model adaptation is performed. In both methods, we first analyze the pronunciation variant rules of non-native speakers and then classify each rule as either a pronunciation variant or an acoustic variant. The state-tying level hybrid method then adapts pronunciation models and acoustic models by accommodating the pronunciation variants in the pronunciation dictionary and by clustering the states of triphone acoustic models using the acoustic variants, respectively. On the other hand, the triphone-modeling level hybrid method initially adapts pronunciation models in the same way as in the state-tying level hybrid method; however, for the acoustic model adaptation, the triphone acoustic models are then re-estimated based on the adapted pronunciation models and the states of the re-estimated triphone acoustic models are clustered using the acoustic variants. From the Korean-spoken English speech recognition experiments, it is shown that ASR systems employing the state-tying and triphone-modeling level adaptation methods can relatively reduce the average word error rates (WERs) by 17.1% and 22.1% for non-native speech, respectively, when compared to a baseline ASR system.

  7. Constitutive auxin response in Physcomitrella reveals complex interactions between Aux/IAA and ARF proteins.

    PubMed

    Lavy, Meirav; Prigge, Michael J; Tao, Sibo; Shain, Stephanie; Kuo, April; Kirchsteiger, Kerstin; Estelle, Mark

    2016-01-01

    The coordinated action of the auxin-sensitive Aux/IAA transcriptional repressors and ARF transcription factors produces complex gene-regulatory networks in plants. Despite their importance, our knowledge of these two protein families is largely based on analysis of stabilized forms of the Aux/IAAs, and studies of a subgroup of ARFs that function as transcriptional activators. To understand how auxin regulates gene expression we generated a Physcomitrella patens line that completely lacks Aux/IAAs. Loss of the repressors causes massive changes in transcription with misregulation of over a third of the annotated genes. Further, we find that the aux/iaa mutant is blind to auxin indicating that auxin regulation of transcription occurs exclusively through Aux/IAA function. We used the aux/iaa mutant as a simplified platform for studies of ARF function and demonstrate that repressing ARFs regulate auxin-induced genes and fine-tune their expression. Further the repressing ARFs coordinate gene induction jointly with activating ARFs and the Aux/IAAs. PMID:27247276

  8. Apigenin and quercetin promote. Delta. pH-dependent accumulation of IAA in membrane vesicles

    SciTech Connect

    Woolard, D.D.; Clark, K.A. )

    1990-05-01

    Flavonoids may act as regulators of polar auxin transport. In the presence of a pH gradient (pH 8{sub in}/6{sub out}) the flavonoids quercetin and apigenin, as well as the synthetic herbicide napthylphthalamic acid (NPA), promote the accumulation of IAA in membrane vesicles from dark-grown zucchini hypocotyls. Simultaneous accumulation of {sup 3}H-IAA (10 nM) and {sup 14}C-butyric acid (5 {mu}M; included as a pH probe) was determined by a filtration assay after incubating the vesicles with 3 nM to 100 {mu}M quercetin, apigenin, NPA or unlabeled IAA. Maximal stimulation (% of Control) was observed with 3 {mu}M NPA (130%), 1 {mu}M quercetin (120%), or 3 {mu}M apigenin (115%); {Delta}pH was not affected by these concentrations. As reported by others, IAA uptake was saturable: 1 {mu}M unlabeled IAA eliminated {Delta}pH-dependent uptake of {sup 3}H-IAA without altering {Delta}pH. However, at 30 to 100 {mu}M, every compound tested collapsed the imposed pH gradient and therefore abolished specific {sup 3}H-IAA uptake.

  9. Graphene oxide modulates root growth of Brassica napus L. and regulates ABA and IAA concentration.

    PubMed

    Cheng, Fan; Liu, Yu-Feng; Lu, Guang-Yuan; Zhang, Xue-Kun; Xie, Ling-Li; Yuan, Cheng-Fei; Xu, Ben-Bo

    2016-04-01

    Researchers have proven that nanomaterials have a significant effect on plant growth and development. To better understand the effects of nanomaterials on plants, Zhongshuang 11 was treated with different concentrations of graphene oxide. The results indicated that 25-100mg/l graphene oxide treatment resulted in shorter seminal root length compared with the control samples. The fresh root weight decreased when treated with 50-100mg/l graphene oxide. The graphene oxide treatment had no significant effect on the Malondialdehyde (MDA) content. Treatment with 50mg/l graphene oxide increased the transcript abundance of genes involved in ABA biosynthesis (NCED, AAO, and ZEP) and some genes involved in IAA biosynthesis (ARF2, ARF8, IAA2, and IAA3), but inhibited the transcript levels of IAA4 and IAA7. The graphene oxide treatment also resulted in a higher ABA content, but a lower IAA content compared with the control samples. The results indicated that graphene oxide modulated the root growth of Brassica napus L. and affected ABA and IAA biosynthesis and concentration. PMID:26945480

  10. Constitutive auxin response in Physcomitrella reveals complex interactions between Aux/IAA and ARF proteins

    PubMed Central

    Lavy, Meirav; Prigge, Michael J; Tao, Sibo; Shain, Stephanie; Kuo, April; Kirchsteiger, Kerstin; Estelle, Mark

    2016-01-01

    The coordinated action of the auxin-sensitive Aux/IAA transcriptional repressors and ARF transcription factors produces complex gene-regulatory networks in plants. Despite their importance, our knowledge of these two protein families is largely based on analysis of stabilized forms of the Aux/IAAs, and studies of a subgroup of ARFs that function as transcriptional activators. To understand how auxin regulates gene expression we generated a Physcomitrella patens line that completely lacks Aux/IAAs. Loss of the repressors causes massive changes in transcription with misregulation of over a third of the annotated genes. Further, we find that the aux/iaa mutant is blind to auxin indicating that auxin regulation of transcription occurs exclusively through Aux/IAA function. We used the aux/iaa mutant as a simplified platform for studies of ARF function and demonstrate that repressing ARFs regulate auxin-induced genes and fine-tune their expression. Further the repressing ARFs coordinate gene induction jointly with activating ARFs and the Aux/IAAs. DOI: http://dx.doi.org/10.7554/eLife.13325.001 PMID:27247276

  11. The role of adaptive management as an operational approach for resource management agencies

    USGS Publications Warehouse

    Johnson, B.L.

    1999-01-01

    In making resource management decisions, agencies use a variety of approaches that involve different levels of political concern, historical precedence, data analyses, and evaluation. Traditional decision-making approaches have often failed to achieve objectives for complex problems in large systems, such as the Everglades or the Colorado River. I contend that adaptive management is the best approach available to agencies for addressing this type of complex problem, although its success has been limited thus far. Traditional decision-making approaches have been fairly successful at addressing relatively straightforward problems in small, replicated systems, such as management of trout in small streams or pulp production in forests. However, this success may be jeopardized as more users place increasing demands on these systems. Adaptive management has received little attention from agencies for addressing problems in small-scale systems, but I suggest that it may be a useful approach for creating a holistic view of common problems and developing guidelines that can then be used in simpler, more traditional approaches to management. Although adaptive management may be more expensive to initiate than traditional approaches, it may be less expensive in the long run if it leads to more effective management. The overall goal of adaptive management is not to maintain an optimal condition of the resource, but to develop an optimal management capacity. This is accomplished by maintaining ecological resilience that allows the system to react to inevitable stresses, and generating flexibility in institutions and stakeholders that allows managers to react when conditions change. The result is that, rather than managing for a single, optimal state, we manage within a range of acceptable outcomes while avoiding catastrophes and irreversible negative effects. Copyright ?? 1999 by The Resilience Alliance.

  12. An adaptive online learning approach for Support Vector Regression: Online-SVR-FID

    NASA Astrophysics Data System (ADS)

    Liu, Jie; Zio, Enrico

    2016-08-01

    Support Vector Regression (SVR) is a popular supervised data-driven approach for building empirical models from available data. Like all data-driven methods, under non-stationary environmental and operational conditions it needs to be provided with adaptive learning capabilities, which might become computationally burdensome with large datasets cumulating dynamically. In this paper, a cost-efficient online adaptive learning approach is proposed for SVR by combining Feature Vector Selection (FVS) and Incremental and Decremental Learning. The proposed approach adaptively modifies the model only when different pattern drifts are detected according to proposed criteria. Two tolerance parameters are introduced in the approach to control the computational complexity, reduce the influence of the intrinsic noise in the data and avoid the overfitting problem of SVR. Comparisons of the prediction results is made with other online learning approaches e.g. NORMA, SOGA, KRLS, Incremental Learning, on several artificial datasets and a real case study concerning time series prediction based on data recorded on a component of a nuclear power generation system. The performance indicators MSE and MARE computed on the test dataset demonstrate the efficiency of the proposed online learning method.

  13. Station-keeping control for a stratospheric airship platform via fuzzy adaptive backstepping approach

    NASA Astrophysics Data System (ADS)

    Yang, Yueneng; Wu, Jie; Zheng, Wei

    2013-04-01

    This paper presents a novel approach for station-keeping control of a stratospheric airship platform in the presence of parametric uncertainty and external disturbance. First, conceptual design of the stratospheric airship platform is introduced, including the target mission, configuration, energy sources, propeller and payload. Second, the dynamics model of the airship platform is presented, and the mathematical model of its horizontal motion is derived. Third, a fuzzy adaptive backstepping control approach is proposed to develop the station-keeping control system for the simplified horizontal motion. The backstepping controller is designed assuming that the airship model is accurately known, and a fuzzy adaptive algorithm is used to approximate the uncertainty of the airship model. The stability of the closed-loop control system is proven via the Lyapunov theorem. Finally, simulation results illustrate the effectiveness and robustness of the proposed control approach.

  14. A Continuum of Approaches Toward Developing Culturally Focused Prevention Interventions: From Adaptation to Grounding

    PubMed Central

    Okamoto, Scott K.; Kulis, Stephen; Marsiglia, Flavio F.; Holleran Steiker, Lori K.; Dustman, Patricia

    2014-01-01

    The purpose of this article is to describe a conceptual model of methods used to develop culturally focused interventions. We describe a continuum of approaches ranging from nonadapted/surface-structure adapted programs to culturally grounded programs, and present recent examples of interventions resulting from the application of each of these approaches. The model has implications for categorizing culturally focused prevention efforts more accurately, and for gauging the time, resources, and level of community engagement necessary to develop programs using each of the different methods. The model also has implications for funding decisions related to the development and evaluation of programs, and for planning of participatory research approaches with community members. PMID:24322970

  15. An Efficient Adaptive Angle-Doppler Compensation Approach for Non-Sidelooking Airborne Radar STAP

    PubMed Central

    Shen, Mingwei; Yu, Jia; Wu, Di; Zhu, Daiyin

    2015-01-01

    In this study, the effects of non-sidelooking airborne radar clutter dispersion on space-time adaptive processing (STAP) is considered, and an efficient adaptive angle-Doppler compensation (EAADC) approach is proposed to improve the clutter suppression performance. In order to reduce the computational complexity, the reduced-dimension sparse reconstruction (RDSR) technique is introduced into the angle-Doppler spectrum estimation to extract the required parameters for compensating the clutter spectral center misalignment. Simulation results to demonstrate the effectiveness of the proposed algorithm are presented. PMID:26053755

  16. An Efficient Adaptive Angle-Doppler Compensation Approach for Non-Sidelooking Airborne Radar STAP.

    PubMed

    Shen, Mingwei; Yu, Jia; Wu, Di; Zhu, Daiyin

    2015-06-04

    In this study, the effects of non-sidelooking airborne radar clutter dispersion on space-time adaptive processing (STAP) is considered, and an efficient adaptive angle-Doppler compensation (EAADC) approach is proposed to improve the clutter suppression performance. In order to reduce the computational complexity, the reduced-dimension sparse reconstruction (RDSR) technique is introduced into the angle-Doppler spectrum estimation to extract the required parameters for compensating the clutter spectral center misalignment. Simulation results to demonstrate the effectiveness of the proposed algorithm are presented.

  17. An Efficient Adaptive Angle-Doppler Compensation Approach for Non-Sidelooking Airborne Radar STAP.

    PubMed

    Shen, Mingwei; Yu, Jia; Wu, Di; Zhu, Daiyin

    2015-01-01

    In this study, the effects of non-sidelooking airborne radar clutter dispersion on space-time adaptive processing (STAP) is considered, and an efficient adaptive angle-Doppler compensation (EAADC) approach is proposed to improve the clutter suppression performance. In order to reduce the computational complexity, the reduced-dimension sparse reconstruction (RDSR) technique is introduced into the angle-Doppler spectrum estimation to extract the required parameters for compensating the clutter spectral center misalignment. Simulation results to demonstrate the effectiveness of the proposed algorithm are presented. PMID:26053755

  18. A new approach for designing self-organizing systems and application to adaptive control

    NASA Technical Reports Server (NTRS)

    Ramamoorthy, P. A.; Zhang, Shi; Lin, Yueqing; Huang, Song

    1993-01-01

    There is tremendous interest in the design of intelligent machines capable of autonomous learning and skillful performance under complex environments. A major task in designing such systems is to make the system plastic and adaptive when presented with new and useful information and stable in response to irrelevant events. A great body of knowledge, based on neuro-physiological concepts, has evolved as a possible solution to this problem. Adaptive resonance theory (ART) is a classical example under this category. The system dynamics of an ART network is described by a set of differential equations with nonlinear functions. An approach for designing self-organizing networks characterized by nonlinear differential equations is proposed.

  19. Constitutive Expression of OsIAA9 Affects Starch Granules Accumulation and Root Gravitropic Response in Arabidopsis

    PubMed Central

    Luo, Sha; Li, Qianqian; Liu, Shanda; Pinas, Nicholaas M.; Tian, Hainan; Wang, Shucai

    2015-01-01

    Auxin/Indole-3-Acetic Acid (Aux/IAA) genes are early auxin response genes ecoding short-lived transcriptional repressors, which regulate auxin signaling in plants by interplay with Auxin Response Factors (ARFs). Most of the Aux/IAA proteins contain four different domains, namely Domain I, Domain II, Domain III, and Domain IV. So far all Aux/IAA mutants with auxin-related phenotypes identified in both Arabidopsis and rice (Oryza sativa) are dominant gain-of-function mutants with mutations in Domain II of the corresponding Aux/IAA proteins, suggest that Aux/IAA proteins in both Arabidopsis and rice are largely functional redundantly, and they may have conserved functions. We report here the functional characterization of a rice Aux/IAA gene, OsIAA9. RT-PCR results showed that expression of OsIAA9 was induced by exogenously applied auxin, suggesting that OsIAA9 is an auxin response gene. Bioinformatic analysis showed that OsIAA9 has a repressor motif in Domain I, a degron in Domain II, and the conserved amino acid signatures for protein-protein interactions in Domain III and Domain IV. By generating transgenic plants expressing GFP-OsIAA9 and examining florescence in the transgenic plants, we found that OsIAA9 is localized in the nucleus. When transfected into protoplasts isolated from rosette leaves of Arabidopsis, OsIAA9 repressed reporter gene expression, and the repression was partially released by exogenously IAA. These results suggest that OsIAA9 is a canonical Aux/IAA protein. Protoplast transfection assays showed that OsIAA9 interacted ARF5, but not ARF6, 7, 8 and 19. Transgenic Arabidopsis plants expressing OsIAA9 have increased number of lateral roots, and reduced gravitropic response. Further analysis showed that OsIAA9 transgenic Arabidopsis plants accumulated fewer granules in their root tips and the distribution of granules was also affected. Taken together, our study showed that OsIAA9 is a transcriptional repressor, and it regulates gravitropic

  20. A Direct Adaptive Control Approach in the Presence of Model Mismatch

    NASA Technical Reports Server (NTRS)

    Joshi, Suresh M.; Tao, Gang; Khong, Thuan

    2009-01-01

    This paper considers the problem of direct model reference adaptive control when the plant-model matching conditions are violated due to abnormal changes in the plant or incorrect knowledge of the plant's mathematical structure. The approach consists of direct adaptation of state feedback gains for state tracking, and simultaneous estimation of the plant-model mismatch. Because of the mismatch, the plant can no longer track the state of the original reference model, but may be able to track a new reference model that still provides satisfactory performance. The reference model is updated if the estimated plant-model mismatch exceeds a bound that is determined via robust stability and/or performance criteria. The resulting controller is a hybrid direct-indirect adaptive controller that offers asymptotic state tracking in the presence of plant-model mismatch as well as parameter deviations.

  1. Prediction of contact forces of underactuated finger by adaptive neuro fuzzy approach

    NASA Astrophysics Data System (ADS)

    Petković, Dalibor; Shamshirband, Shahaboddin; Abbasi, Almas; Kiani, Kourosh; Al-Shammari, Eiman Tamah

    2015-12-01

    To obtain adaptive finger passive underactuation can be used. Underactuation principle can be used to adapt shapes of the fingers for grasping objects. The fingers with underactuation do not require control algorithm. In this study a kinetostatic model of the underactuated finger mechanism was analyzed. The underactuation is achieved by adding the compliance in every finger joint. Since the contact forces of the finger depend on contact position of the finger and object, it is suitable to make a prediction model for the contact forces in function of contact positions of the finger and grasping objects. In this study prediction of the contact forces was established by a soft computing approach. Adaptive neuro-fuzzy inference system (ANFIS) was applied as the soft computing method to perform the prediction of the finger contact forces.

  2. A simple and flexible graphical approach for adaptive group-sequential clinical trials.

    PubMed

    Sugitani, Toshifumi; Bretz, Frank; Maurer, Willi

    2016-01-01

    In this article, we introduce a graphical approach to testing multiple hypotheses in group-sequential clinical trials allowing for midterm design modifications. It is intended for structured study objectives in adaptive clinical trials and extends the graphical group-sequential designs from Maurer and Bretz (Statistics in Biopharmaceutical Research 2013; 5: 311-320) to adaptive trial designs. The resulting test strategies can be visualized graphically and performed iteratively. We illustrate the methodology with two examples from our clinical trial practice. First, we consider a three-armed gold-standard trial with the option to reallocate patients to either the test drug or the active control group, while stopping the recruitment of patients to placebo, after having demonstrated superiority of the test drug over placebo at an interim analysis. Second, we consider a confirmatory two-stage adaptive design with treatment selection at interim.

  3. A human factors approach to adapted access device prescription and customization.

    PubMed

    August, S; Weiss, P L

    1992-01-01

    Adapted access device prescription and customization is often a lengthy and cumbersome process. To date, few objective procedures are available to assist in the prescription process. Rather, clinician and client rely on a trial-and-error approach that is often severely constrained by the size of their adaptive device collection as well as the extent of clinical expertise. Furthermore, the large number of available options and lack of information delineating the mechanical and physical characteristics of these devices means that therapists must take time away from direct clinical contact to probe each adaptation in detail. There is available in the human factors domain a body of literature that is highly relevant to adapted access. Of particular interest are the studies that have addressed issues related to the suitability of standard and alternative input devices in terms of task productivity (via improvements in input speed, accuracy, and endurance), and their ability to minimize the risk of acute and chronic work-related dysfunction. This paper aims to consider the relevance of human factors research for physically disabled individuals. Three human factors issues--digit travel, digit loading, and device positioning--have been selected as representative of factors important in the configuration of adapted access devices.

  4. A Unified Nonlinear Adaptive Approach for Detection and Isolation of Engine Faults

    NASA Technical Reports Server (NTRS)

    Tang, Liang; DeCastro, Jonathan A.; Zhang, Xiaodong; Farfan-Ramos, Luis; Simon, Donald L.

    2010-01-01

    A challenging problem in aircraft engine health management (EHM) system development is to detect and isolate faults in system components (i.e., compressor, turbine), actuators, and sensors. Existing nonlinear EHM methods often deal with component faults, actuator faults, and sensor faults separately, which may potentially lead to incorrect diagnostic decisions and unnecessary maintenance. Therefore, it would be ideal to address sensor faults, actuator faults, and component faults under one unified framework. This paper presents a systematic and unified nonlinear adaptive framework for detecting and isolating sensor faults, actuator faults, and component faults for aircraft engines. The fault detection and isolation (FDI) architecture consists of a parallel bank of nonlinear adaptive estimators. Adaptive thresholds are appropriately designed such that, in the presence of a particular fault, all components of the residual generated by the adaptive estimator corresponding to the actual fault type remain below their thresholds. If the faults are sufficiently different, then at least one component of the residual generated by each remaining adaptive estimator should exceed its threshold. Therefore, based on the specific response of the residuals, sensor faults, actuator faults, and component faults can be isolated. The effectiveness of the approach was evaluated using the NASA C-MAPSS turbofan engine model, and simulation results are presented.

  5. Approaches to evaluating climate change impacts on species: a guide to initiating the adaptation planning process.

    PubMed

    Rowland, Erika L; Davison, Jennifer E; Graumlich, Lisa J

    2011-03-01

    Assessing the impact of climate change on species and associated management objectives is a critical initial step for engaging in the adaptation planning process. Multiple approaches are available. While all possess limitations to their application associated with the uncertainties inherent in the data and models that inform their results, conducting and incorporating impact assessments into the adaptation planning process at least provides some basis for making resource management decisions that are becoming inevitable in the face of rapidly changing climate. Here we provide a non-exhaustive review of long-standing (e.g., species distribution models) and newly developed (e.g., vulnerability indices) methods used to anticipate the response to climate change of individual species as a guide for managers grappling with how to begin the climate change adaptation process. We address the limitations (e.g., uncertainties in climate change projections) associated with these methods, and other considerations for matching appropriate assessment approaches with the management questions and goals. Thorough consideration of the objectives, scope, scale, time frame and available resources for a climate impact assessment allows for informed method selection. With many data sets and tools available on-line, the capacity to undertake and/or benefit from existing species impact assessments is accessible to those engaged in resource management. With some understanding of potential impacts, even if limited, adaptation planning begins to move toward the development of management strategies and targeted actions that may help to sustain functioning ecosystems and their associated services into the future.

  6. An implicit and adaptive nonlinear frequency domain approach for periodic viscous flows

    NASA Astrophysics Data System (ADS)

    Mosahebi, A.; Nadarajah, S.

    2014-12-01

    An implicit nonlinear Lower-Upper symmetric Gauss-Seidel (LU-SGS) solver has been extended to the adaptive Nonlinear Frequency Domain method (adaptive NLFD) for periodic viscous flows. The discretized equations are linearized in both spatial and temporal directions, yielding an innovative segregate approach, where the effects of the neighboring cells are transferred to the right-hand-side and are updated iteratively. This property of the solver is aligned with the adaptive NLFD concept, in which different cells have different number of modes; hence, should be treated individually. The segregate analysis of the modal equations prevents assembling and inversion of a large left-hand-side matrix, when high number of modes are involved. This is an important characteristic for a selected flow solver of the adaptive NLFD method, where a high modal content may be required in highly unsteady parts of the flow field. The implicit nonlinear LU-SGS solver has demonstrated to be both robust and computationally efficient as the number of modes is increased. The developed solver is thoroughly validated for the laminar vortex shedding behind a stationary cylinder, high angle of attack NACA0012 airfoil, and a plunging NACA0012 airfoil. An order of magnitude improvement in the computational time is observed through the developed implicit approach over the classical modified 5-stage Runge-Kutta method.

  7. IAA8 Involved in Lateral Root Formation Interacts with the TIR1 Auxin Receptor and ARF Transcription Factors in Arabidopsis

    PubMed Central

    Egusa, Mayumi; Nishimoto, Nami; Sakurai, Sumiko; Sakamoto, Naho; Kaminaka, Hironori

    2012-01-01

    The expression of auxin-responsive genes is regulated by the TIR1/AFB auxin receptor-dependent degradation of Aux/IAA transcriptional repressors, which interact with auxin-responsive factors (ARFs). Most of the 29 Aux/IAA genes present in Arabidopsis have not been functionally characterized to date. IAA8 appears to have a distinct function from the other Aux/IAA genes, due to its unique transcriptional response to auxin and the stability of its encoded protein. In this study, we characterized the function of Arabidopsis IAA8 in various developmental processes governed by auxin and in the transcriptional regulation of the auxin response. Transgenic plants expressing estrogen-inducible IAA8 (XVE::IAA8) exhibited significantly fewer lateral roots than the wild type, and an IAA8 loss-of-function mutant exhibited significantly more. Ectopic overexpression of IAA8 resulted in abnormal gravitropism. The strong induction of early auxin-responsive marker genes by auxin treatment was delayed by IAA8 overexpression. GFP-fusion analysis revealed that IAA8 localized not only to the nucleus, but, in contrast to other Aux/IAAs, also to the cytosol. Furthermore, we demonstrated that IAA8 interacts with TIR1, in an auxin-dependent fashion, and with ARF proteins, both in yeast and in planta. Taken together, our results show that IAA8 is involved in lateral root formation, and that this process is regulated through the interaction with the TIR1 auxin receptor and ARF transcription factors in the nucleus. PMID:22912871

  8. Bayesian approach increases accuracy when selecting cowpea genotypes with high adaptability and phenotypic stability.

    PubMed

    Barroso, L M A; Teodoro, P E; Nascimento, M; Torres, F E; Dos Santos, A; Corrêa, A M; Sagrilo, E; Corrêa, C C G; Silva, F A; Ceccon, G

    2016-01-01

    This study aimed to verify that a Bayesian approach could be used for the selection of upright cowpea genotypes with high adaptability and phenotypic stability, and the study also evaluated the efficiency of using informative and minimally informative a priori distributions. Six trials were conducted in randomized blocks, and the grain yield of 17 upright cowpea genotypes was assessed. To represent the minimally informative a priori distributions, a probability distribution with high variance was used, and a meta-analysis concept was adopted to represent the informative a priori distributions. Bayes factors were used to conduct comparisons between the a priori distributions. The Bayesian approach was effective for selection of upright cowpea genotypes with high adaptability and phenotypic stability using the Eberhart and Russell method. Bayes factors indicated that the use of informative a priori distributions provided more accurate results than minimally informative a priori distributions. PMID:26985961

  9. Bayesian approach increases accuracy when selecting cowpea genotypes with high adaptability and phenotypic stability.

    PubMed

    Barroso, L M A; Teodoro, P E; Nascimento, M; Torres, F E; Dos Santos, A; Corrêa, A M; Sagrilo, E; Corrêa, C C G; Silva, F A; Ceccon, G

    2016-03-11

    This study aimed to verify that a Bayesian approach could be used for the selection of upright cowpea genotypes with high adaptability and phenotypic stability, and the study also evaluated the efficiency of using informative and minimally informative a priori distributions. Six trials were conducted in randomized blocks, and the grain yield of 17 upright cowpea genotypes was assessed. To represent the minimally informative a priori distributions, a probability distribution with high variance was used, and a meta-analysis concept was adopted to represent the informative a priori distributions. Bayes factors were used to conduct comparisons between the a priori distributions. The Bayesian approach was effective for selection of upright cowpea genotypes with high adaptability and phenotypic stability using the Eberhart and Russell method. Bayes factors indicated that the use of informative a priori distributions provided more accurate results than minimally informative a priori distributions.

  10. An Adaptive Particle Filtering Approach to Tracking Modes in a Varying Shallow Ocean Environment

    SciTech Connect

    Candy, J V

    2011-03-22

    The shallow ocean environment is ever changing mostly due to temperature variations in its upper layers (< 100m) directly affecting sound propagation throughout. The need to develop processors that are capable of tracking these changes implies a stochastic as well as an 'adaptive' design. The stochastic requirement follows directly from the multitude of variations created by uncertain parameters and noise. Some work has been accomplished in this area, but the stochastic nature was constrained to Gaussian uncertainties. It has been clear for a long time that this constraint was not particularly realistic leading a Bayesian approach that enables the representation of any uncertainty distribution. Sequential Bayesian techniques enable a class of processors capable of performing in an uncertain, nonstationary (varying statistics), non-Gaussian, variable shallow ocean. In this paper adaptive processors providing enhanced signals for acoustic hydrophonemeasurements on a vertical array as well as enhanced modal function estimates are developed. Synthetic data is provided to demonstrate that this approach is viable.

  11. Increased IAA transport in axillary buds upon release from apical dominance

    SciTech Connect

    Tamas, I.A.; Reimels, A.J. )

    1989-04-01

    To investigate the transport of indoleacetic acid (IAA) simultaneously in the stem and the axillary bud, bud-bearing nodal stem segments of Phaseolus vulgaris L. were excised and agar blocks containing {sup 14}C-IAA or {sup 3}H-IAA were placed on the apical cut surface and the bud stump respectively. A plain receiver block was placed on the basal end. After a period of transport, the stem segment and the attached bud stump were sectioned, and the activity of sections and agar blocks was counted. We found that the transport of {sup 3}H-IAA from the bud stump to the receiver was greatly accelerated in plants decapitated one or two days prior to the experiment, compared to the intact controls. Decapitation also caused a decrease in the ability of the stem axis to transport {sup 14}C-IAA from the apical to the basal end of the stem segment. The increased ability of the axillary bud to transport IAA, relative to that of the stem axis, may play a role int he release of the bud from apical dominance.

  12. Introduction of a novel pathway for IAA biosynthesis to rhizobia alters vetch root nodule development.

    PubMed

    Camerini, Serena; Senatore, Beatrice; Lonardo, Enza; Imperlini, Esther; Bianco, Carmen; Moschetti, Giancarlo; Rotino, Giuseppe L; Campion, Bruno; Defez, Roberto

    2008-07-01

    We introduced into Rhizobium leguminosarum bv. viciae LPR1105 a new pathway for the biosynthesis of the auxin, indole-3-acetic acid (IAA), under the control of a stationary phase-activated promoter active both in free-living bacteria and bacteroids. The newly introduced genes are the iaaM gene from Pseudomonas savastanoi and the tms2 gene from Agrobacterium tumefaciens. Free-living bacteria harbouring the promoter-iaaMtms2 construct release into the growth medium 14-fold more IAA than the wild-type parental strain. This IAA overproducing R. l. viciae, the RD20 strain, elicits the development of vetch root nodules containing up to 60-fold more IAA than nodules infected by the wild-type strain LPR1105. Vetch root nodules derived from RD20 are fewer in number per plant, heavier in terms of dry weight and show an enlarged and more active meristem. A significant increase in acetylene reduction activity was measured in nodules elicited in vetch by RD20.

  13. How phytohormone IAA and chelator EDTA affect lead uptake by Zn/Cd hyperaccumulator Picris divaricata.

    PubMed

    Du, Rui-Jun; He, Er-Kai; Tang, Ye-Tao; Hu, Peng-Jie; Ying, Rong-Rong; Morel, Jean-Louis; Qiu, Rong-Liang

    2011-01-01

    In this paper, the effects of indole-3-acetic acid (IAA) and/or ethylenediaminetetraacetic acid (EDTA) on lead uptake by a Zn/Cd hyperaccumulator Picris divaricata were studied. P. divaricata responded to Pb by better root system and increased biomass in presence of phytohormone IAA, which was able to reduce the inhibiting effects of Pb on transpiration without reducing the uptake of Pb The application of 100 microM IAA increased plant transpiration rate by about 20% and Pb concentration in leaves by about 37.3% as compared to treatment exposed to Pb alone. The enhanced phytoextraction efficiency could be attributed to the mechanisms played by IAA through alleviating Pb toxicity, creating better root system and plant biomass, promoting a higher transpiration rate as well as regulating the level of nutrient elements. On the contrary, inefficiency of phytoextraction was found with EDTA or the combination of IAA and EDTA probably because most Pb was in the form of Pb-EDTA complex which blocked the uptake by P. divaricata. The present study demonstrated that IAA was able to enhance the phytoextraction of Pb by Zn/Cd hyperaccumulator P. divaricata, providing a feasible method for the phytoremediation of polymetallic contaminated soils. PMID:21972569

  14. A unique approach to the development of adaptive sensor systems for future spacecraft

    NASA Technical Reports Server (NTRS)

    Schappell, R. T.; Tietz, J. C.; Sivertson, W. E.; Wilson, R. G.

    1979-01-01

    In the Shuttle era, it should be possible to develop adaptive remote sensor systems serving more directly specific researcher and user needs and at the same time alleviating the data management problem via intelligent sensor capabilities. The present paper provides a summary of such an approach, wherein specific capabilities have been developed for future global monitoring applications. A detailed description of FILE-I (Feature Identification and Location Experiment) is included along with a summary of future experiments currently under development.

  15. Performance Monitoring and Assessment of Neuro-Adaptive Controllers for Aerospace Applications Using a Bayesian Approach

    NASA Technical Reports Server (NTRS)

    Gupta, Pramod; Guenther, Kurt; Hodgkinson, John; Jacklin, Stephen; Richard, Michael; Schumann, Johann; Soares, Fola

    2005-01-01

    Modern exploration missions require modern control systems-control systems that can handle catastrophic changes in the system's behavior, compensate for slow deterioration in sustained operations, and support fast system ID. Adaptive controllers, based upon Neural Networks have these capabilities, but they can only be used safely if proper verification & validation (V&V) can be done. In this paper we present our V & V approach and simulation result within NASA's Intelligent Flight Control Systems (IFCS).

  16. Adaptive Critic Neural Network-Based Terminal Area Energy Management and Approach and Landing Guidance

    NASA Technical Reports Server (NTRS)

    Grantham, Katie

    2003-01-01

    Reusable Launch Vehicles (RLVs) have different mission requirements than the Space Shuttle, which is used for benchmark guidance design. Therefore, alternative Terminal Area Energy Management (TAEM) and Approach and Landing (A/L) Guidance schemes can be examined in the interest of cost reduction. A neural network based solution for a finite horizon trajectory optimization problem is presented in this paper. In this approach the optimal trajectory of the vehicle is produced by adaptive critic based neural networks, which were trained off-line to maintain a gradual glideslope.

  17. Reducing False Negative Reads in RFID Data Streams Using an Adaptive Sliding-Window Approach

    PubMed Central

    Massawe, Libe Valentine; Kinyua, Johnson D. M.; Vermaak, Herman

    2012-01-01

    Unreliability of the data streams generated by RFID readers is among the primary factors which limit the widespread adoption of the RFID technology. RFID data cleaning is, therefore, an essential task in the RFID middleware systems in order to reduce reading errors, and to allow these data streams to be used to make a correct interpretation and analysis of the physical world they are representing. In this paper we propose an adaptive sliding-window based approach called WSTD which is capable of efficiently coping with both environmental variation and tag dynamics. Our experimental results demonstrate the efficacy of the proposed approach. PMID:22666027

  18. A decision analysis approach to climate adaptation: comparing multiple pathways for multi-decadal decision making

    NASA Astrophysics Data System (ADS)

    Lin, B. B.; Little, L.

    2013-12-01

    Policy planners around the world are required to consider the implications of adapting to climatic change across spatial contexts and decadal timeframes. However, local level information for planning is often poorly defined, even though climate adaptation decision-making is made at this scale. This is especially true when considering sea level rise and coastal impacts of climate change. We present a simple approach using sea level rise simulations paired with adaptation scenarios to assess a range of adaptation options available to local councils dealing with issues of beach recession under present and future sea level rise and storm surge. Erosion and beach recession pose a large socioeconomic risk to coastal communities because of the loss of key coastal infrastructure. We examine the well-known adaptation technique of beach nourishment and assess various timings and amounts of beach nourishment at decadal time spans in relation to beach recession impacts. The objective was to identify an adaptation strategy that would allow for a low frequency of management interventions, the maintenance of beach width, and the ability to minimize variation in beach width over the 2010 to 2100 simulation period. 1000 replications of each adaptation option were produced against the 90 year simulation in order to model the ability each adaptation option to achieve the three key objectives. Three sets of adaptation scenarios were identified. Within each scenario, a number of adaptation options were tested. The three scenarios were: 1) Fixed periodic beach replenishment of specific amounts at 20 and 50 year intervals, 2) Beach replenishment to the initial beach width based on trigger levels of recession (5m, 10m, 20m), and 3) Fixed period beach replenishment of a variable amount at decadal intervals (every 10, 20, 30, 40, 50 years). For each adaptation option, we show the effectiveness of each beach replenishment scenario to maintain beach width and consider the implications of more

  19. Modern control concepts in hydrology. [parameter identification in adaptive stochastic control approach

    NASA Technical Reports Server (NTRS)

    Duong, N.; Winn, C. B.; Johnson, G. R.

    1975-01-01

    Two approaches to an identification problem in hydrology are presented, based upon concepts from modern control and estimation theory. The first approach treats the identification of unknown parameters in a hydrologic system subject to noisy inputs as an adaptive linear stochastic control problem; the second approach alters the model equation to account for the random part in the inputs, and then uses a nonlinear estimation scheme to estimate the unknown parameters. Both approaches use state-space concepts. The identification schemes are sequential and adaptive and can handle either time-invariant or time-dependent parameters. They are used to identify parameters in the Prasad model of rainfall-runoff. The results obtained are encouraging and confirm the results from two previous studies; the first using numerical integration of the model equation along with a trial-and-error procedure, and the second using a quasi-linearization technique. The proposed approaches offer a systematic way of analyzing the rainfall-runoff process when the input data are imbedded in noise.

  20. A New Approach to Interference Excision in Radio Astronomy: Real-Time Adaptive Cancellation

    NASA Astrophysics Data System (ADS)

    Barnbaum, Cecilia; Bradley, Richard F.

    1998-11-01

    Every year, an increasing amount of radio-frequency (RF) spectrum in the VHF, UHF, and microwave bands is being utilized to support new commercial and military ventures, and all have the potential to interfere with radio astronomy observations. Such services already cause problems for radio astronomy even in very remote observing sites, and the potential for this form of light pollution to grow is alarming. Preventive measures to eliminate interference through FCC legislation and ITU agreements can be effective; however, many times this approach is inadequate and interference excision at the receiver is necessary. Conventional techniques such as RF filters, RF shielding, and postprocessing of data have been only somewhat successful, but none has been sufficient. Adaptive interference cancellation is a real-time approach to interference excision that has not been used before in radio astronomy. We describe here, for the first time, adaptive interference cancellation in the context of radio astronomy instrumentation, and we present initial results for our prototype receiver. In the 1960s, analog adaptive interference cancelers were developed that obtain a high degree of cancellation in problems of radio communications and radar. However, analog systems lack the dynamic range, noised performance, and versatility required by radio astronomy. The concept of digital adaptive interference cancellation was introduced in the mid-1960s as a way to reduce unwanted noise in low-frequency (audio) systems. Examples of such systems include the canceling of maternal ECG in fetal electrocardiography and the reduction of engine noise in the passenger compartments of automobiles. These audio-frequency applications require bandwidths of only a few tens of kilohertz. Only recently has high-speed digital filter technology made high dynamic range adaptive canceling possible in a bandwidth as large as a few megahertz, finally opening the door to application in radio astronomy. We have

  1. An optimal dynamic inversion-based neuro-adaptive approach for treatment of chronic myelogenous leukemia.

    PubMed

    Padhi, Radhakant; Kothari, Mangal

    2007-09-01

    Combining the advanced techniques of optimal dynamic inversion and model-following neuro-adaptive control design, an innovative technique is presented to design an automatic drug administration strategy for effective treatment of chronic myelogenous leukemia (CML). A recently developed nonlinear mathematical model for cell dynamics is used to design the controller (medication dosage). First, a nominal controller is designed based on the principle of optimal dynamic inversion. This controller can treat the nominal model patients (patients who can be described by the mathematical model used here with the nominal parameter values) effectively. However, since the system parameters for a realistic model patient can be different from that of the nominal model patients, simulation studies for such patients indicate that the nominal controller is either inefficient or, worse, ineffective; i.e. the trajectory of the number of cancer cells either shows non-satisfactory transient behavior or it grows in an unstable manner. Hence, to make the drug dosage history more realistic and patient-specific, a model-following neuro-adaptive controller is augmented to the nominal controller. In this adaptive approach, a neural network trained online facilitates a new adaptive controller. The training process of the neural network is based on Lyapunov stability theory, which guarantees both stability of the cancer cell dynamics as well as boundedness of the network weights. From simulation studies, this adaptive control design approach is found to be very effective to treat the CML disease for realistic patients. Sufficient generality is retained in the mathematical developments so that the technique can be applied to other similar nonlinear control design problems as well.

  2. An Integrated Systems Approach to Designing Climate Change Adaptation Policy in Water Resources

    NASA Astrophysics Data System (ADS)

    Ryu, D.; Malano, H. M.; Davidson, B.; George, B.

    2014-12-01

    Climate change projections are characterised by large uncertainties with rainfall variability being the key challenge in designing adaptation policies. Climate change adaptation in water resources shows all the typical characteristics of 'wicked' problems typified by cognitive uncertainty as new scientific knowledge becomes available, problem instability, knowledge imperfection and strategic uncertainty due to institutional changes that inevitably occur over time. Planning that is characterised by uncertainties and instability requires an approach that can accommodate flexibility and adaptive capacity for decision-making. An ability to take corrective measures in the event that scenarios and responses envisaged initially derive into forms at some future stage. We present an integrated-multidisciplinary and comprehensive framework designed to interface and inform science and decision making in the formulation of water resource management strategies to deal with climate change in the Musi Catchment of Andhra Pradesh, India. At the core of this framework is a dialogue between stakeholders, decision makers and scientists to define a set of plausible responses to an ensemble of climate change scenarios derived from global climate modelling. The modelling framework used to evaluate the resulting combination of climate scenarios and adaptation responses includes the surface and groundwater assessment models (SWAT & MODFLOW) and the water allocation modelling (REALM) to determine the water security of each adaptation strategy. Three climate scenarios extracted from downscaled climate models were selected for evaluation together with four agreed responses—changing cropping patterns, increasing watershed development, changing the volume of groundwater extraction and improving irrigation efficiency. Water security in this context is represented by the combination of level of water availability and its associated security of supply for three economic activities (agriculture

  3. Genome-wide analysis of Aux/IAA gene family in Solanaceae species using tomato as a model.

    PubMed

    Wu, Jian; Peng, Zhen; Liu, Songyu; He, Yanjun; Cheng, Lin; Kong, Fuling; Wang, Jie; Lu, Gang

    2012-04-01

    Auxin plays key roles in a wide variety of plant activities, including embryo development, leaf formation, phototropism, fruit development and root initiation and development. Auxin/indoleacetic acid (Aux/IAA) genes, encoding short-lived nuclear proteins, are key regulators in the auxin transduction pathway. But how they work is still unknown. In order to conduct a systematic analysis of this gene family in Solanaceae species, a genome-wide search for the homologues of auxin response genes was carried out. Here, 26 and 27 non redundant AUX/IAAs were identified in tomato and potato, respectively. Using tomato as a model, a comprehensive overview of SlIAA gene family is presented, including the gene structures, phylogeny, chromosome locations, conserved motifs and cis-elements in promoter sequences. A phylogenetic tree generated from alignments of the predicted protein sequences of 31 OsIAAs, 29 AtIAAs, 31 ZmIAAs, and 26 SlIAAs revealed that these IAAs were clustered into three major groups and ten subgroups. Among them, seven subgroups were present in both monocot and dicot species, which indicated that the major functional diversification within the IAA family predated the monocot/dicot divergence. In contrast, group C and some other subgroups seemed to be species-specific. Quantitative real-time PCR (qRT-PCR) analysis showed that 19 of the 26 SlIAA genes could be detected in all tomato organs/tissues, however, seven of them were specifically expressed in some of tomato tissues. The transcript abundance of 17 SlIAA genes were increased within a few hours when the seedlings were treated with exogenous IAA. However, those of other six SlIAAs were decreased. The results of stress treatments showed that most SIIAA family genes responded to at least one of the three stress treatments, however, they exhibited diverse expression levels under different abiotic stress conditions in tomato seedlings. SlIAA20, SlIAA21 and SlIAA22 were not significantly influenced by stress

  4. A problem-oriented approach to understanding adaptation: lessons learnt from Alpine Shire, Victoria Australia.

    NASA Astrophysics Data System (ADS)

    Roman, Carolina

    2010-05-01

    Climate change is gaining attention as a significant strategic issue for localities that rely on their business sectors for economic viability. For businesses in the tourism sector, considerable research effort has sought to characterise the vulnerability to the likely impacts of future climate change through scenarios or ‘end-point' approaches (Kelly & Adger, 2000). Whilst useful, there are few demonstrable case studies that complement such work with a ‘start-point' approach that seeks to explore contextual vulnerability (O'Brien et al., 2007). This broader approach is inclusive of climate change as a process operating within a biophysical system and allows recognition of the complex interactions that occur in the coupled human-environmental system. A problem-oriented and interdisciplinary approach was employed at Alpine Shire, in northeast Victoria Australia, to explore the concept of contextual vulnerability and adaptability to stressors that include, but are not limited to climatic change. Using a policy sciences approach, the objective was to identify factors that influence existing vulnerabilities and that might consequently act as barriers to effective adaptation for the Shire's business community involved in the tourism sector. Analyses of results suggest that many threats, including the effects climate change, compete for the resources, strategy and direction of local tourism management bodies. Further analysis of conditioning factors revealed that many complex and interacting factors define the vulnerability and adaptive capacity of the Shire's tourism sector to the challenges of global change, which collectively have more immediate implications for policy and planning than long-term future climate change scenarios. An approximation of the common interest, i.e. enhancing capacity in business acumen amongst tourism operators, would facilitate adaptability and sustainability through the enhancement of social capital in this business community. Kelly, P

  5. A Functional Approach To Uncover the Low-Temperature Adaptation Strategies of the Archaeon Methanosarcina barkeri

    PubMed Central

    McCay, Paul; Fuszard, Matthew; Botting, Catherine H.; Abram, Florence; O'Flaherty, Vincent

    2013-01-01

    Low-temperature anaerobic digestion (LTAD) technology is underpinned by a diverse microbial community. The methanogenic archaea represent a key functional group in these consortia, undertaking CO2 reduction as well as acetate and methylated C1 metabolism with subsequent biogas (40 to 60% CH4 and 30 to 50% CO2) formation. However, the cold adaptation strategies, which allow methanogens to function efficiently in LTAD, remain unclear. Here, a pure-culture proteomic approach was employed to study the functional characteristics of Methanosarcina barkeri (optimum growth temperature, 37°C), which has been detected in LTAD bioreactors. Two experimental approaches were undertaken. The first approach aimed to characterize a low-temperature shock response (LTSR) of M. barkeri DSMZ 800T grown at 37°C with a temperature drop to 15°C, while the second experimental approach aimed to examine the low-temperature adaptation strategies (LTAS) of the same strain when it was grown at 15°C. The latter experiment employed cell viability and growth measurements (optical density at 600 nm [OD600]), which directly compared M. barkeri cells grown at 15°C with those grown at 37°C. During the LTSR experiment, a total of 127 proteins were detected in 37°C and 15°C samples, with 20 proteins differentially expressed with respect to temperature, while in the LTAS experiment 39% of proteins identified were differentially expressed between phases of growth. Functional categories included methanogenesis, cellular information processing, and chaperones. By applying a polyphasic approach (proteomics and growth studies), insights into the low-temperature adaptation capacity of this mesophilically characterized methanogen were obtained which suggest that the metabolically diverse Methanosarcinaceae could be functionally relevant for LTAD systems. PMID:23645201

  6. Dynamic experiment design regularization approach to adaptive imaging with array radar/SAR sensor systems.

    PubMed

    Shkvarko, Yuriy; Tuxpan, José; Santos, Stewart

    2011-01-01

    We consider a problem of high-resolution array radar/SAR imaging formalized in terms of a nonlinear ill-posed inverse problem of nonparametric estimation of the power spatial spectrum pattern (SSP) of the random wavefield scattered from a remotely sensed scene observed through a kernel signal formation operator and contaminated with random Gaussian noise. First, the Sobolev-type solution space is constructed to specify the class of consistent kernel SSP estimators with the reproducing kernel structures adapted to the metrics in such the solution space. Next, the "model-free" variational analysis (VA)-based image enhancement approach and the "model-based" descriptive experiment design (DEED) regularization paradigm are unified into a new dynamic experiment design (DYED) regularization framework. Application of the proposed DYED framework to the adaptive array radar/SAR imaging problem leads to a class of two-level (DEED-VA) regularized SSP reconstruction techniques that aggregate the kernel adaptive anisotropic windowing with the projections onto convex sets to enforce the consistency and robustness of the overall iterative SSP estimators. We also show how the proposed DYED regularization method may be considered as a generalization of the MVDR, APES and other high-resolution nonparametric adaptive radar sensing techniques. A family of the DYED-related algorithms is constructed and their effectiveness is finally illustrated via numerical simulations.

  7. Dynamic Experiment Design Regularization Approach to Adaptive Imaging with Array Radar/SAR Sensor Systems

    PubMed Central

    Shkvarko, Yuriy; Tuxpan, José; Santos, Stewart

    2011-01-01

    We consider a problem of high-resolution array radar/SAR imaging formalized in terms of a nonlinear ill-posed inverse problem of nonparametric estimation of the power spatial spectrum pattern (SSP) of the random wavefield scattered from a remotely sensed scene observed through a kernel signal formation operator and contaminated with random Gaussian noise. First, the Sobolev-type solution space is constructed to specify the class of consistent kernel SSP estimators with the reproducing kernel structures adapted to the metrics in such the solution space. Next, the “model-free” variational analysis (VA)-based image enhancement approach and the “model-based” descriptive experiment design (DEED) regularization paradigm are unified into a new dynamic experiment design (DYED) regularization framework. Application of the proposed DYED framework to the adaptive array radar/SAR imaging problem leads to a class of two-level (DEED-VA) regularized SSP reconstruction techniques that aggregate the kernel adaptive anisotropic windowing with the projections onto convex sets to enforce the consistency and robustness of the overall iterative SSP estimators. We also show how the proposed DYED regularization method may be considered as a generalization of the MVDR, APES and other high-resolution nonparametric adaptive radar sensing techniques. A family of the DYED-related algorithms is constructed and their effectiveness is finally illustrated via numerical simulations. PMID:22163859

  8. Testing for Adaptation to Climate in Arabidopsis thaliana: A Calibrated Common Garden Approach

    PubMed Central

    Rutter, Matthew T.; Fenster, Charles B.

    2007-01-01

    Background and Aims A recent method used to test for local adaptation is a common garden experiment where analyses are calibrated to the environmental conditions of the garden. In this study the calibrated common garden approach is used to test for patterns of adaptation to climate in accessions of Arabidopsis thaliana. Methods Seedlings from 21 accessions of A. thaliana were planted outdoors in College Park, MD, USA, and development was monitored during the course of a growing season. ANOVA and multiple regression analysis were used to determine if development traits were significant predictors of plant success. Previously published data relating to accessional differences in genetic and physiological characters were also examined. Historical records of climate were used to evaluate whether properties of the site of origin of an accession affected the fitness of plants in a novel environment. Key Results By calibrating the analysis to the climatic conditions of the common garden site, performance differences were detected among the accessions consistent with a pattern of adaptation to latitude and climatic conditions. Relatively higher accession fitness was predicted by a latitude and climatic history similar to that of College Park in April and May during the main growth period of this experiment. The climatic histories of the accessions were better predictors of performance than many of the life-history and growth measures taken during the experiment. Conclusions It is concluded that the calibrated common garden experiment can detect local adaptation and guide subsequent reciprocal transplant experiments. PMID:17293351

  9. Transcriptome Profiling of Petal Abscission Zone and Functional Analysis of an Aux/IAA Family Gene RhIAA16 Involved in Petal Shedding in Rose

    PubMed Central

    Gao, Yuerong; Liu, Chun; Li, Xiaodong; Xu, Haiqian; Liang, Yue; Ma, Nan; Fei, Zhangjun; Gao, Junping; Jiang, Cai-Zhong; Ma, Chao

    2016-01-01

    Roses are one of the most important cut flowers among ornamental plants. Rose flower longevity is largely dependent on the timing of petal shedding occurrence. To understand the molecular mechanism underlying petal abscission in rose, we performed transcriptome profiling of the petal abscission zone during petal shedding using Illumina technology. We identified a total of 2592 differentially transcribed genes (DTGs) during rose petal shedding. Gene ontology term enrichment and pathway analysis revealed that major biochemical pathways the DTGs were involved in included ethylene biosynthesis, starch degradation, superpathway of cytosolic glycolysis, pyruvate dehydrogenase and TCA cycle, photorespiration and the lactose degradation III pathway. This suggests that alterations in carbon metabolism are an important part of rose petal abscission. Among these DTGs, approximately 150 genes putatively encoding transcription factors were identified in rose abscission zone. These included zinc finger, WRKY, ERF, and Aux/IAA gene families, suggesting that petal abscission involves complex transcriptional reprogramming. Approximately 108 DTGs were related to hormone pathways, of which auxin and ethylene related DTGs were the largest groups including 52 and 41 genes, respectively. These also included 12 DTGs related to gibberellin and 6 DTGs in jasmonic acid pathway. Surprisingly, no DTGs involved in the biosynthesis/signaling of abscisic acid, cytokinin, brassinosteroid, and salicylic acid pathways were detected. Moreover, among DTGs related to auxin, we identified an Aux/IAA gene RhIAA16 that was up-regulated in response to petal shedding. Down-regulation of RhIAA16 by virus-induced gene silencing in rose promoted petal abscission, suggesting that RhIAA16 plays an important role in rose petal abscission. PMID:27695465

  10. Transcriptome Profiling of Petal Abscission Zone and Functional Analysis of an Aux/IAA Family Gene RhIAA16 Involved in Petal Shedding in Rose

    PubMed Central

    Gao, Yuerong; Liu, Chun; Li, Xiaodong; Xu, Haiqian; Liang, Yue; Ma, Nan; Fei, Zhangjun; Gao, Junping; Jiang, Cai-Zhong; Ma, Chao

    2016-01-01

    Roses are one of the most important cut flowers among ornamental plants. Rose flower longevity is largely dependent on the timing of petal shedding occurrence. To understand the molecular mechanism underlying petal abscission in rose, we performed transcriptome profiling of the petal abscission zone during petal shedding using Illumina technology. We identified a total of 2592 differentially transcribed genes (DTGs) during rose petal shedding. Gene ontology term enrichment and pathway analysis revealed that major biochemical pathways the DTGs were involved in included ethylene biosynthesis, starch degradation, superpathway of cytosolic glycolysis, pyruvate dehydrogenase and TCA cycle, photorespiration and the lactose degradation III pathway. This suggests that alterations in carbon metabolism are an important part of rose petal abscission. Among these DTGs, approximately 150 genes putatively encoding transcription factors were identified in rose abscission zone. These included zinc finger, WRKY, ERF, and Aux/IAA gene families, suggesting that petal abscission involves complex transcriptional reprogramming. Approximately 108 DTGs were related to hormone pathways, of which auxin and ethylene related DTGs were the largest groups including 52 and 41 genes, respectively. These also included 12 DTGs related to gibberellin and 6 DTGs in jasmonic acid pathway. Surprisingly, no DTGs involved in the biosynthesis/signaling of abscisic acid, cytokinin, brassinosteroid, and salicylic acid pathways were detected. Moreover, among DTGs related to auxin, we identified an Aux/IAA gene RhIAA16 that was up-regulated in response to petal shedding. Down-regulation of RhIAA16 by virus-induced gene silencing in rose promoted petal abscission, suggesting that RhIAA16 plays an important role in rose petal abscission.

  11. Validation of MIPAS IMK/IAA methane profiles

    NASA Astrophysics Data System (ADS)

    Laeng, A.; Plieninger, J.; von Clarmann, T.; Grabowski, U.; Stiller, G.; Eckert, E.; Glatthor, N.; Haenel, F.; Kellmann, S.; Kiefer, M.; Linden, A.; Lossow, S.; Deaver, L.; Engel, A.; Hervig, M.; Levin, I.; McHugh, M.; Noël, S.; Toon, G.; Walker, K.

    2015-06-01

    The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) was an infra-red (IR) limb emission spectrometer on the Envisat platform. It measured during day and night, pole-to-pole, over an altitude range from 6 to 70 km in nominal mode and up to 170 km in special modes, depending on the measurement mode, producing more than 1000 profiles day-1. We present the results of a validation study of methane version V5R_CH4_222 retrieved with the IMK/IAA MIPAS scientific level 2 processor. The level 1 spectra are provided by ESA, the version 5 was used. The time period covered corresponds to the period when MIPAS measured at reduced spectral resolution, i.e. 2005-2012. The comparison with satellite instruments includes the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS), the HALogen Occultation Experiment (HALOE), the Solar Occultation For Ice Experiment (SOFIE) and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). Furthermore, comparisons with MkIV balloon-borne solar occultation measurements and with air sampling measurements performed by the University of Frankfurt are presented. The validation activities include bias determination, in selected cases, assessment of histograms and comparison of corresponding climatologies. Above 50 km altitude, MIPAS methane mixing ratios agree within 3% with ACE-FTS and SOFIE. Between 30 and 40 km an agreement within 3% with SCIAMACHY has been found. In the middle stratosphere, there is no clear indication of a MIPAS bias since comparisons with various instruments contradict each other. In the lower stratosphere (below about 25-30 km) MIPAS CH4 is biased high with respect to satellite instruments, and the most likely estimate of this bias is 14%. However, in the comparison with CH4 data obtained from cryosampler measurements, there is no evidence of a MIPAS high bias between 20 and 25 km altitude. Precision validation is performed on collocated MIPAS-MIPAS pairs

  12. Validation of MIPAS IMK/IAA methane profiles

    NASA Astrophysics Data System (ADS)

    Laeng, A.; Plieninger, J.; von Clarmann, T.; Grabowski, U.; Stiller, G.; Eckert, E.; Glatthor, N.; Haenel, F.; Kellmann, S.; Kiefer, M.; Linden, A.; Lossow, S.; Deaver, L.; Engel, A.; Hervig, M.; Levin, I.; McHugh, M.; Noël, S.; Toon, G.; Walker, K.

    2015-12-01

    The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is an infrared (IR) limb emission spectrometer on the Envisat platform. It measures trace gas distributions during day and night, pole-to-pole, over an altitude range from 6 to 70 km in nominal mode and up to 170 km in special modes, depending on the measurement mode, producing more than 1000 profiles day-1. We present the results of a validation study of methane, version V5R_CH4_222, retrieved with the IMK/IAA (Institut für Meteorologie und Klimaforschung, Karlsruhe/Instituto de Astrofisica de Andalucia, Grenada) MIPAS scientific level 2 processor. The level 1 spectra are provided by the ESA (European Space Agency) and version 5 was used. The time period covered is 2005-2012, which corresponds to the period when MIPAS measured trace gas distributions at a reduced spectral resolution of 0.0625 cm-1. The comparison with satellite instruments includes the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS), the HALogen Occultation Experiment (HALOE), the Solar Occultation For Ice Experiment (SOFIE) and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). Furthermore, comparisons with MkIV balloon-borne solar occultation measurements and with air sampling measurements performed by the University of Frankfurt are presented. The validation activities include bias determination, assessment of stability, precision validation, analysis of histograms and comparison of corresponding climatologies. Above 50 km altitude, MIPAS methane mixing ratios agree within 3 % with ACE-FTS and SOFIE. Between 30 and 40 km an agreement within 3 % with SCIAMACHY has been found. In the middle stratosphere, there is no clear indication of a MIPAS bias since comparisons with various instruments contradict each other. In the lower stratosphere (below 25 km) MIPAS CH4 is biased high with respect to satellite instruments, and the most likely estimate of this bias is 14

  13. Participation of IAA in transduction of gravistimulus in apical cells of moss protonema

    NASA Astrophysics Data System (ADS)

    Oksyniuk, U. A.; Khorkavtsiv, O. Y.; Lesniak, Y. I.

    Growth movements of vascular plant axis organs -- photo-, gravi- and other tropisms -- are tightly connected with IAA transport (Hertel, 1983; Medvedev, 1996; Kiss, 2000). Moss protonema synthesizes IAA (indole-3-acetic acid) and transports it basipetally favouring growth and differentiation of caulonema (Bopp, 1979; Rose, Bopp, 1983; Rose et al., 1983). We aimed at studying the role of IAA in moss protonema gravitropism using exogenous IAA, 1-NAA (1-naphthaleneacetic acid), 2,4D (2,4-dichlorophenoxyacetic acid) and inhibitors of polar IAA transport -- phytotropins NPA (N-1-naphthylphthalamic acid) and TIBA (2,3,5-triiodobenzoic acid). Six-day gravitropic protonema of Ceratodon purpureus and Pohlia nutans were taken for experiments. Auxin and phytotropins solutions were laid on protonema mats the latters being kept in solutions for 30 min. Then the surplus of solutions were poured off and Petri dishes were placed vertically for 6 h. 20 μ M of IAA and of other synthetic auxins did not significantly influence the angle of protonema gravity bending, 40 μ M of the agents, howewer, reduced the per cent of apical cells bendings and their angles. The most expressed influence on the angles of bending had the inhibitors of polar IAA transport -- NPA. 0,1 -- 3,0 μ M of this phytotropin did not change the form of apical cell, did not disturb the general distribution of amyloplasts and did not significantly lower the per cent and the value of gravity bending angle, though 10 μ M of the phytotropin - inhibited gravity bending. The mixture of 1-NAA and NPA having been added into the medium the influence of NPA was lowered and gravitropic growth renewed in course of time. 10 μ M of other phytopropin TIBA also inhibited gravitropism of Ceratodon purpureus and Pohlia nutans protonema. The analysis of basipetal transport of IAA in moss rhizoids and protonema may indicate the availability of special IAA transport in these structures (Bopp, Cerier, 1988). On the basis of the

  14. The co-adaptive neural network approach to the Euclidean Travelling Salesman Problem.

    PubMed

    Cochrane, E M; Beasley, J E

    2003-12-01

    In this paper we consider the Euclidean Travelling Salesman Problem (ETSP). This is the problem of finding the shortest tour around a number of cities where the cities correspond to points in the Euclidean plane and the distances between cities are given by the usual Euclidean distance metric. We present a review of the literature with respect to neural network (NN) approaches for the ETSP, and the computational results that have been reported. Based upon this review we highlight two areas that are, in our judgement, currently neglected/lacking in the literature. These are: failure to make significant use of publicly available ETSP test problems in computational work, failure to address co-operation between neurons. Drawing upon our literature survey this paper presents a new Self-Organising NN approach, called the Co-Adaptive Net, which involves not just unsupervised learning to train neurons, but also allows neurons to co-operate and compete amongst themselves depending on their situation. Our Co-Adaptive Net algorithm also includes a number of algorithmic mechanisms that, based upon our literature review, we consider to have contributed to the computational success of previous algorithms. Results for 91 publicly available standard ETSP's are presented in this paper. The largest of these problems involves 85,900 cities. This paper presents: the most extensive computational evaluation of any NN approach on publicly available ETSP test problems that has been made to date in the literature, a NN approach that performs better, with respect to solution quality and/or computation time, than other NN approaches given previously in the literature. Drawing upon computational results produced as a result of the DIMACS TSP Challenge, we highlight the fact that none of the current NN approaches for the ETSP can compete with state of the art Operations Research heuristics. We discuss why we consider continuing to study and develop NN approaches for the ETSP to be of value.

  15. An adaptive gating approach for x-ray dose reduction during cardiac interventional procedures

    SciTech Connect

    Abdel-Malek, A.; Yassa, F.; Bloomer, J. )

    1994-03-01

    The increasing number of cardiac interventional procedures has resulted in a tremendous increase in the absorbed x-ray dose by radiologists as well as patients. A new method is presented for x-ray dose reduction which utilizes adaptive tube pulse-rate scheduling in pulsed fluoroscopic systems. In the proposed system, pulse-rate scheduling depends on the heart muscle activity phase determined through continuous guided segmentation of the patient's electrocardiogram (ECG). Displaying images generated at the proposed adaptive nonuniform rate is visually unacceptable; therefore, a frame-filling approach is devised to ensure a 30 frame/sec display rate. The authors adopted two approaches for the frame-filling portion of the system depending on the imaging mode used in the procedure. During cine-mode imaging (high x-ray dose), collected image frame-to-frame pixel motion is estimated using a pel-recursive algorithm followed by motion-based pixel interpolation to estimate the frames necessary to increase the rate to 30 frames/sec. The other frame-filling approach is adopted during fluoro-mode imaging (low x-ray dose), characterized by low signal-to-noise ratio images. This approach consists of simply holding the last collected frame for as many frames as necessary to maintain the real-time display rate.

  16. Solution-Adaptive Cartesian Cell Approach for Viscous and Inviscid Flows

    NASA Technical Reports Server (NTRS)

    Coirier, William J.; Powell, Kenneth G.

    1996-01-01

    A Cartesian cell-based approach for adaptively refined solutions of the Euler and Navier-Stokes equations in two dimensions is presented. Grids about geometrically complicated bodies are generated automatically, by the recursive subdivision of a single Cartesian cell encompassing the entire flow domain. Where the resulting cells intersect bodies, polygonal cut cells are created using modified polygon-clipping algorithms. The grid is stored in a binary tree data structure that provides a natural means of obtaining cell-to-cell connectivity and of carrying out solution-adaptive mesh refinement. The Euler and Navier-Stokes equations are solved on the resulting grids using a finite volume formulation. The convective terms are upwinded: A linear reconstruction of the primitive variables is performed, providing input states to an approximate Riemann solver for computing the fluxes between neighboring cells. The results of a study comparing the accuracy and positivity of two classes of cell-centered, viscous gradient reconstruction procedures is briefly summarized. Adaptively refined solutions of the Navier-Stokes equations are shown using the more robust of these gradient reconstruction procedures, where the results computed by the Cartesian approach are compared to theory, experiment, and other accepted computational results for a series of low and moderate Reynolds number flows.

  17. Adaptive variable-fidelity wavelet-based eddy-capturing approaches for compressible turbulence

    NASA Astrophysics Data System (ADS)

    Brown-Dymkoski, Eric; Vasilyev, Oleg V.

    2015-11-01

    Multiresolution wavelet methods have been developed for efficient simulation of compressible turbulence. They rely upon a filter to identify dynamically important coherent flow structures and adapt the mesh to resolve them. The filter threshold parameter, which can be specified globally or locally, allows for a continuous tradeoff between computational cost and fidelity, ranging seamlessly between DNS and adaptive LES. There are two main approaches to specifying the adaptive threshold parameter. It can be imposed as a numerical error bound, or alternatively, derived from real-time flow phenomena to ensure correct simulation of desired turbulent physics. As LES relies on often imprecise model formulations that require a high-quality mesh, this variable-fidelity approach offers a further tool for improving simulation by targeting deficiencies and locally increasing the resolution. Simultaneous physical and numerical criteria, derived from compressible flow physics and the governing equations, are used to identify turbulent regions and evaluate the fidelity. Several benchmark cases are considered to demonstrate the ability to capture variable density and thermodynamic effects in compressible turbulence. This work was supported by NSF under grant No. CBET-1236505.

  18. Cloning and expression analysis of novel Aux/IAA family genes in Gossypium hirsutum.

    PubMed

    Han, Xiaoyong; Xu, Xiaoyang; Fang, David D; Zhang, Tianzhen; Guo, Wangzhen

    2012-07-15

    Members of the Aux/IAA gene family encode proteins that mediate the responses of auxin-regulated gene expression and regulate various aspects of plant morphological development. Here, we provide the first identification and characterization of nine cDNAs encoding the complete open reading frame (ORF) of the Aux/IAA family in cotton. These were designated GhAux1 to GhAux9 (Gossypiumhirsutum Aux/IAA). The proteins encoded by these nine genes had either whole or partially conserved domains of the Aux/IAA superfamily, with sequence identity ranging from 14% to 69%. A pair of homeologs exists for each Aux/IAA in G. hirsutum acc. TM-1 with high identity both in ORF sequences and amino acid level. Tissue- and organ-specific analysis showed that transcripts of GhAux1, GhAux2, and GhAux3 were abundant in vegetative organs, whereas GhAux4, GhAux5, GhAux6, and GhAux7 were preferentially expressed in ovules on the day of anthesis. GhAux8 and GhIAA16 (previously reported) were also preferentially expressed during fiber developmental stages, especially GhAux8 in fiber early elongation stages, and GhIAA16 in fiber initiation and secondary cell wall thickening stage. GhAux9 was specifically expressed in developing fibers. During the fiber initiation stage, except for GhAux3 and GhAux6, the expression of the other eight GhAuxs in various lintless-fuzzless and linted-fuzzless mutants demonstrated that they were significantly up-regulated compared with linted-fuzzy TM-1. PMID:22575728

  19. An adaptive fusion approach for infrared and visible images based on NSCT and compressed sensing

    NASA Astrophysics Data System (ADS)

    Zhang, Qiong; Maldague, Xavier

    2016-01-01

    A novel nonsubsampled contourlet transform (NSCT) based image fusion approach, implementing an adaptive-Gaussian (AG) fuzzy membership method, compressed sensing (CS) technique, total variation (TV) based gradient descent reconstruction algorithm, is proposed for the fusion computation of infrared and visible images. Compared with wavelet, contourlet, or any other multi-resolution analysis method, NSCT has many evident advantages, such as multi-scale, multi-direction, and translation invariance. As is known, a fuzzy set is characterized by its membership function (MF), while the commonly known Gaussian fuzzy membership degree can be introduced to establish an adaptive control of the fusion processing. The compressed sensing technique can sparsely sample the image information in a certain sampling rate, and the sparse signal can be recovered by solving a convex problem employing gradient descent based iterative algorithm(s). In the proposed fusion process, the pre-enhanced infrared image and the visible image are decomposed into low-frequency subbands and high-frequency subbands, respectively, via the NSCT method as a first step. The low-frequency coefficients are fused using the adaptive regional average energy rule; the highest-frequency coefficients are fused using the maximum absolute selection rule; the other high-frequency coefficients are sparsely sampled, fused using the adaptive-Gaussian regional standard deviation rule, and then recovered by employing the total variation based gradient descent recovery algorithm. Experimental results and human visual perception illustrate the effectiveness and advantages of the proposed fusion approach. The efficiency and robustness are also analyzed and discussed through different evaluation methods, such as the standard deviation, Shannon entropy, root-mean-square error, mutual information and edge-based similarity index.

  20. Origin and basipetal transport of the IAA responsible for rooting of carnation cuttings.

    PubMed

    Garrido, Germán; Ramón Guerrero, Juan; Angel Cano, Emilio; Acosta, Manuel; Sánchez-Bravo, José

    2002-02-01

    The origin and transport of the IAA responsible for rooting was studied in carnation (Dianthus caryophyllus L.) cuttings obtained from secondary shoots of the mother plants. The presence of mature leaves in the cuttings was essential for rooting. Removal of the apex and/or the youngest leaves did not reduce the rooting percentage as long as mature leaves remained attached. Removal of mature leaves inhibited rooting for a 24-day period during which the basal leaves grew and reached maturity. After this period rooting progressed as in intact cuttings. Auxin (NAA + IBA) applied to the stem base of defoliated cuttings was about 60% as effective as mature leaves in stimulating rooting. Application of NPA to the basal internode resulted in full inhibition of rooting. The view, deduced from these results, that auxin from mature leaves is the main factor controlling the rooting process was reinforced by the fact that mature leaves contained IAA and exported labelled IAA to the stem. The distribution of radioactivity after application of (5-3H)-IAA to mature leaves showed that auxin movement in the stem was basipetal and sensitive to NPA inhibition. The features of this transport were studied by applying 3H-IAA to the apical cut surface of stem sections excised from cuttings. The intensity of the transport was lower in the oldest node than in the basal internode, probably due to the presence of vascular traces of leaves. Irrespective of the localization of the sections and the carnation cultivar used, basipetal IAA transport was severely reduced when the temperature was lowered from 25 to 4 degrees C. The polar nature of the IAA transport in the sections was confirmed by the inhibition produced by NPA. Local application of IAA to different tissues of the sections revealed that polar auxin transport was associated with the vascular cylinder, the transport in the pith and cortex being low and apolar. The present results strongly support the conclusion that IAA originating

  1. One Adaptive Synchronization Approach for Fractional-Order Chaotic System with Fractional-Order 1 < q < 2

    PubMed Central

    Zhou, Ping; Bai, Rongji

    2014-01-01

    Based on a new stability result of equilibrium point in nonlinear fractional-order systems for fractional-order lying in 1 < q < 2, one adaptive synchronization approach is established. The adaptive synchronization for the fractional-order Lorenz chaotic system with fractional-order 1 < q < 2 is considered. Numerical simulations show the validity and feasibility of the proposed scheme. PMID:25247207

  2. One adaptive synchronization approach for fractional-order chaotic system with fractional-order 1 < q < 2.

    PubMed

    Zhou, Ping; Bai, Rongji

    2014-01-01

    Based on a new stability result of equilibrium point in nonlinear fractional-order systems for fractional-order lying in 1 < q < 2, one adaptive synchronization approach is established. The adaptive synchronization for the fractional-order Lorenz chaotic system with fractional-order 1 < q < 2 is considered. Numerical simulations show the validity and feasibility of the proposed scheme. PMID:25247207

  3. Approach for Structurally Clearing an Adaptive Compliant Trailing Edge Flap for Flight

    NASA Technical Reports Server (NTRS)

    Miller, Eric J.; Lokos, William A.; Cruz, Josue; Crampton, Glen; Stephens, Craig A.; Kota, Sridhar; Ervin, Gregory; Flick, Pete

    2015-01-01

    The Adaptive Compliant Trailing Edge (ACTE) flap was flown on the NASA Gulfstream GIII test bed at the NASA Armstrong Flight Research Center. This smoothly curving flap replaced the existing Fowler flaps creating a seamless control surface. This compliant structure, developed by FlexSys Inc. in partnership with Air Force Research Laboratory, supported NASA objectives for airframe structural noise reduction, aerodynamic efficiency, and wing weight reduction through gust load alleviation. A thorough structures airworthiness approach was developed to move this project safely to flight.

  4. Stereo matching based on adaptive support-weight approach in RGB vector space.

    PubMed

    Geng, Yingnan; Zhao, Yan; Chen, Hexin

    2012-06-01

    Gradient similarity is a simple, yet powerful, data descriptor which shows robustness in stereo matching. In this paper, a RGB vector space is defined for stereo matching. Based on the adaptive support-weight approach, a matching algorithm, which uses the pixel gradient similarity, color similarity, and proximity in RGB vector space to compute the corresponding support-weights and dissimilarity measurements, is proposed. The experimental results are evaluated on the Middlebury stereo benchmark, showing that our algorithm outperforms other stereo matching algorithms and the algorithm with gradient similarity can achieve better results in stereo matching. PMID:22695592

  5. An Adaptive Nonlinear Aircraft Maneuvering Envelope Estimation Approach for Online Applications

    NASA Technical Reports Server (NTRS)

    Schuet, Stefan R.; Lombaerts, Thomas Jan; Acosta, Diana; Wheeler, Kevin; Kaneshige, John

    2014-01-01

    A nonlinear aircraft model is presented and used to develop an overall unified robust and adaptive approach to passive trim and maneuverability envelope estimation with uncertainty quantification. The concept of time scale separation makes this method suitable for the online characterization of altered safe maneuvering limitations after impairment. The results can be used to provide pilot feedback and/or be combined with flight planning, trajectory generation, and guidance algorithms to help maintain safe aircraft operations in both nominal and off-nominal scenarios.

  6. Evidence-Based Approach to Treating Lateral Epicondylitis Using the Occupational Adaptation Model.

    PubMed

    Bachman, Stephanie

    2016-01-01

    The occupational therapy Centennial Vision reinforces the importance of informing consumers about the benefit of occupational therapy and continuing to advocate for the unique client-centered role of occupational therapy. Occupational therapy practitioners working in hand therapy have traditionally found it difficult to combine the biomechanical foundations of hand therapy with the fundamental client-centered tenets of occupational therapy. Embracing our historical roots will become more important as health care evolves and third-party payers continue to scrutinize the need for the profession of occupational therapy. This article outlines a client-centered approach for hand therapists for the treatment of lateral epicondylitis using the Occupational Adaptation Model.

  7. Superiority of radiobinding assay over ELISA for detection of IAAs in newly diagnosed type I diabetic children

    SciTech Connect

    Levy-Marchal, C.; Bridel, M.P.; Sodoyez-Goffaux, F.; Koch, M.; Tichet, J.; Czernichow, P.; Sodoyez, J.C. )

    1991-01-01

    Liquid- or solid-phase assays have been used for insulin autoantibody (IAA) determination, and the method of IAA measurement has not been standardized. IAAs were determined by radiobinding assay (RBA) and enzyme-linked immunosorbent assay (ELISA) in two large age-matched groups of nondiabetic and newly diagnosed insulin-dependent (type I) diabetic children. Positivity for IAA by RBA (greater than or equal to nondiabetic mean + 3SD) was 2 of 178 (1.1%) and 55 of 173 (32%) in nondiabetic and diabetic children, respectively. Prevalence of IAA by RBA was significantly higher in the youngest age-group (63% between 0-4 yr). Positivity for IAA by ELISA was 1 of 178 (0.6%) and 8 of 169 (4.7%) in nondiabetic and diabetic children, respectively. Concordance rates between both assays were 0 of 3 (0%) in control subjects and 5 of 58 (8.6%) in diabetic children. We conclude that RBA is more appropriate than ELISA for IAA detection at the onset of the disease. In addition, because available data suggest that IAAs detected by RBA only are high-affinity antibodies, it is tempting to speculate that IAAs reflect a mature immune reaction against endogenous insulin.

  8. Protein-protein interaction and gene co-expression maps of ARFs and Aux/IAAs in Arabidopsis

    PubMed Central

    Piya, Sarbottam; Shrestha, Sandesh K.; Binder, Brad; Stewart, C. Neal; Hewezi, Tarek

    2014-01-01

    The phytohormone auxin regulates nearly all aspects of plant growth and development. Based on the current model in Arabidopsis thaliana, Auxin/indole-3-acetic acid (Aux/IAA) proteins repress auxin-inducible genes by inhibiting auxin response transcription factors (ARFs). Experimental evidence suggests that heterodimerization between Aux/IAA and ARF proteins are related to their unique biological functions. The objective of this study was to generate the Aux/IAA-ARF protein-protein interaction map using full length sequences and locate the interacting protein pairs to specific gene co-expression networks in order to define tissue-specific responses of the Aux/IAA-ARF interactome. Pairwise interactions between 19 ARFs and 29 Aux/IAAs resulted in the identification of 213 specific interactions of which 79 interactions were previously unknown. The incorporation of co-expression profiles with protein-protein interaction data revealed a strong correlation of gene co-expression for 70% of the ARF-Aux/IAA interacting pairs in at least one tissue/organ, indicative of the biological significance of these interactions. Importantly, ARF4-8 and 19, which were found to interact with almost all Aux-Aux/IAA showed broad co-expression relationships with Aux/IAA genes, thus, formed the central hubs of the co-expression network. Our analyses provide new insights into the biological significance of ARF-Aux/IAA associations in the morphogenesis and development of various plant tissues and organs. PMID:25566309

  9. Developing integrated approaches to climate change adaptation in rural communities of the Peruvian Andes

    NASA Astrophysics Data System (ADS)

    Huggel, Christian

    2010-05-01

    Over centuries, Andean communities have developed strategies to cope with climate variability and extremes, such as cold waves or droughts, which can have severe impacts on their welfare. Nevertheless, the rural population, living at altitudes of 3000 to 4000 m asl or even higher, remains highly vulnerable to external stresses, partly because of the extreme living conditions, partly as a consequence of high poverty. Moreover, recent studies indicate that climatic extreme events have increased in frequency in the past years. A Peruvian-Swiss Climate Change Adaptation Programme in Peru (PACC) is currently undertaking strong efforts to understand the links between climatic conditions and local livelihood assets. The goal is to propose viable strategies for adaptation in collaboration with the local population and governments. The program considers three main areas of action, i.e. (i) water resource management; (ii) disaster risk reduction; and (iii) food security. The scientific studies carried out within the programme follow a highly transdisciplinary approach, spanning the whole range from natural and social sciences. Moreover, the scientific Peruvian-Swiss collaboration is closely connected to people and institutions operating at the implementation and political level. In this contribution we report on first results of thematic studies, address critical questions, and outline the potential of integrative research for climate change adaptation in mountain regions in the context of a developing country.

  10. Impact of adaptive signal control on major and minor approach delay

    SciTech Connect

    Wolshon, B.; Taylor, W.C.

    1999-01-01

    One of the primary difficulties in completing evaluations of real-time adaptive traffic signal systems has been the lack of effective modeling tools to perform controlled and repeatable analytical experiments. Recently, a method to analyze the delay characteristics of an existing real-time adaptive traffic signal control system has been developed. The procedure has been used to evaluate the performance of the Sydney Coordinated Adaptive Traffic System (SCATS) in South Lyon, Michigan. The objective of this study was to more closely examine the relationship of major and minor street delay under the SCATS and fixed-time forms of signal control. The effect on left turn delay at critical locations was also compared to the delay change in the through traffic. The comparisons showed that SCATS control resulted in significant delay reductions to left turn traffic compared to the through movements. The improvement was especially pronounced at the major street approaches. To further address the delay effect of SCATS control in South Lyon, the relationships between volume, delay, and green time of the various traffic moments were also compared. These comparisons showed that SCATS tended to allocate more green time to left turn traffic when compared to the fixed-time system.

  11. New approach for selecting pectinase producing mutants of Aspergillus niger well adapted to solid state fermentation.

    PubMed

    Antier, P; Minjares, A; Roussos, S; Viniegra-González, G

    1993-01-01

    The aim of this paper is to review and study a new approach for improving strains of Aspergillus niger specially adapted to produce pectinases by Solid State Fermentation (SSF) with materials having low levels of water activity (a(w)), i.e., coffee pulp. Special emphasis is placed on the use of two antimetabolic compounds: 2-deoxy-glucose (DG) and 2,4-dinitro-phenol (DNP) combined with a water depressant (ethylene glycol = EG) in order to put strong selection pressures on UV treated spores from parental strain C28B25 isolated from a coffee plantation. Such a strain was found to be DG sensitive. Results suggested the existence of a reciprocal relation between adaptation of isolated strains to SSF or to Submerged Fermentation (SmF) systems. Preliminary physiological analysis of isolated strains showed that at least some few initially DG resistant mutants could revert to DG sensitive phenotype but conserving increased pectinase production. Also it was found that phenotype for DNP resistance could be associated to changes of DG resistance. Finally, it was found that low levels of a(w) produced by adding 15% EG to agar plates, were a significant selection factor for strains well adapted to SSF system.

  12. A Risk-based Model Predictive Control Approach to Adaptive Interventions in Behavioral Health

    PubMed Central

    Zafra-Cabeza, Ascensión; Rivera, Daniel E.; Collins, Linda M.; Ridao, Miguel A.; Camacho, Eduardo F.

    2010-01-01

    This paper examines how control engineering and risk management techniques can be applied in the field of behavioral health through their use in the design and implementation of adaptive behavioral interventions. Adaptive interventions are gaining increasing acceptance as a means to improve prevention and treatment of chronic, relapsing disorders, such as abuse of alcohol, tobacco, and other drugs, mental illness, and obesity. A risk-based Model Predictive Control (MPC) algorithm is developed for a hypothetical intervention inspired by Fast Track, a real-life program whose long-term goal is the prevention of conduct disorders in at-risk children. The MPC-based algorithm decides on the appropriate frequency of counselor home visits, mentoring sessions, and the availability of after-school recreation activities by relying on a model that includes identifiable risks, their costs, and the cost/benefit assessment of mitigating actions. MPC is particularly suited for the problem because of its constraint-handling capabilities, and its ability to scale to interventions involving multiple tailoring variables. By systematically accounting for risks and adapting treatment components over time, an MPC approach as described in this paper can increase intervention effectiveness and adherence while reducing waste, resulting in advantages over conventional fixed treatment. A series of simulations are conducted under varying conditions to demonstrate the effectiveness of the algorithm. PMID:21643450

  13. Interindividual differences in intraindividual changes in proactivity during organizational entry: a latent growth modeling approach to understanding newcomer adaptation.

    PubMed

    Chan, D; Schmitt, N

    2000-04-01

    Intraindividual change over time is the essence of the change phenomenon hypothesized to occur in the individual newcomer adaptation process. Many important adaptation questions cannot be answered without an adequate conceptualization and assessment of intraindividual change. Using a latent growth modeling approach to data collected from 146 doctoral program newcomers over 4 repeated measurements spaced at 1-month intervals, the authors explicitly modeled interindividual differences in intraindividual changes in newcomer proactivities (information seeking, relationship building) and proximal adaptation outcomes (task mastery, role clarity, social integration) during organizational entry. Results indicated that changes in proactivity may be related to newcomer characteristics and adaptation outcomes in interesting ways that have not been previously examined.

  14. Where do adaptive shifts occur during invasion A multidisciplinary approach to unravel cold adaptation in a tropical ant species invading the Mediterranean zone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although evolution is now recognized as improving the invasive success of populations, where and when key adaptation event(s) occur often remains unclear. Here we used a multidisciplinary approach to disentangle the eco-evolutionary scenario of invasion of a Mediterranean zone (i.e. Israel) by the t...

  15. Reconstruction for distributed video coding: a Markov random field approach with context-adaptive smoothness prior

    NASA Astrophysics Data System (ADS)

    Zhang, Yongsheng; Xiong, Hongkai; He, Zhihai; Yu, Songyu

    2010-07-01

    An important issue in Wyner-Ziv video coding is the reconstruction of Wyner-Ziv frames with decoded bit-planes. So far, there are two major approaches: the Maximum a Posteriori (MAP) reconstruction and the Minimum Mean Square Error (MMSE) reconstruction algorithms. However, these approaches do not exploit smoothness constraints in natural images. In this paper, we model a Wyner-Ziv frame by Markov random fields (MRFs), and produce reconstruction results by finding an MAP estimation of the MRF model. In the MRF model, the energy function consists of two terms: a data term, MSE distortion metric in this paper, measuring the statistical correlation between side-information and the source, and a smoothness term enforcing spatial coherence. In order to better describe the spatial constraints of images, we propose a context-adaptive smoothness term by analyzing the correspondence between the output of Slepian-Wolf decoding and successive frames available at decoders. The significance of the smoothness term varies in accordance with the spatial variation within different regions. To some extent, the proposed approach is an extension to the MAP and MMSE approaches by exploiting the intrinsic smoothness characteristic of natural images. Experimental results demonstrate a considerable performance gain compared with the MAP and MMSE approaches.

  16. Adaptive Filter-bank Approach to Restoration and Spectral Analysis of Gapped Data

    NASA Astrophysics Data System (ADS)

    Stoica, Petre; Larsson, Erik G.; Li, Jian

    2000-10-01

    The main topic of this paper is the nonparametric estimation of complex (both amplitude and phase) spectra from gapped data, as well as the restoration of such data. The focus is on the extension of the APES (amplitude and phase estimation) approach to data sequences with gaps. APES, which is one of the most successful existing nonparametric approaches to the spectral analysis of full data sequences, uses a bank of narrowband adaptive (both frequency and data dependent) filters to estimate the spectrum. A recent interpretation of this approach showed that the filterbank used by APES and the resulting spectrum minimize a least-squares (LS) fitting criterion between the filtered sequence and its spectral decomposition. The extended approach, which is called GAPES for somewhat obvious reasons, capitalizes on the aforementioned interpretation: it minimizes the APES-LS fitting criterion with respect to the missing data as well. This should be a sensible thing to do whenever the full data sequence is stationary, and hence the missing data have the same spectral content as the available data. We use both simulated and real data examples to show that GAPES estimated spectra and interpolated data sequences have excellent accuracy. We also show the performance gain achieved by GAPES over two of the most commonly used approaches for gapped-data spectral analysis, viz., the periodogram and the parametric CLEAN method. This work was partly supported by the Swedish Foundation for Strategic Research.

  17. Adaptive convex combination approach for the identification of improper quaternion processes.

    PubMed

    Ujang, Bukhari Che; Jahanchahi, Cyrus; Took, Clive Cheong; Mandic, Danilo P

    2014-01-01

    Data-adaptive optimal modeling and identification of real-world vector sensor data is provided by combining the fractional tap-length (FT) approach with model order selection in the quaternion domain. To account rigorously for the generality of such processes, both second-order circular (proper) and noncircular (improper), the proposed approach in this paper combines the FT length optimization with both the strictly linear quaternion least mean square (QLMS) and widely linear QLMS (WL-QLMS). A collaborative approach based on QLMS and WL-QLMS is shown to both identify the type of processes (proper or improper) and to track their optimal parameters in real time. Analysis shows that monitoring the evolution of the convex mixing parameter within the collaborative approach allows us to track the improperness in real time. Further insight into the properties of those algorithms is provided by establishing a relationship between the steady-state error and optimal model order. The approach is supported by simulations on model order selection and identification of both strictly linear and widely linear quaternion-valued systems, such as those routinely used in renewable energy (wind) and human-centered computing (biomechanics). PMID:24806652

  18. Difference, adapted physical activity and human development: potential contribution of capabilities approach.

    PubMed

    Silva, Carla Filomena; Howe, P David

    2012-01-01

    This paper is a call to Adapted Physical Activity (APA) professionals to increase the reflexive nature of their practice. Drawing upon Foucault's concept of governmentality (1977) APA action may work against its own publicized goals of empowerment and self-determination. To highlight these inconsistencies, we will draw upon historical and social factors that explain the implicit dangers of practice not following policy. We propose that APA practitioners work according to ethical guidelines, based upon a capabilities approach (Nussbaum, 2006, 2011; Sen, 2009) to counteract possible adverse effects of APA practitioner action. A capabilities approach is conducive to the development of each individual's human potential, by holistically considering the consequences of physical activity (i.e., biological, cultural, social, and psychological dimensions). To conclude, this paper will offer suggestions that may lead to an ethical reflection aligned with the best interest of APA's users.

  19. Adaptive life simulator: A novel approach to modeling the cardiovascular system

    SciTech Connect

    Kangas, L.J.; Keller, P.E.; Hashem, S.

    1995-06-01

    In this paper, an adaptive life simulator (ALS) is introduced. The ALS models a subset of the dynamics of the cardiovascular behavior of an individual by using a recurrent artificial neural network. These models are developed for use in applications that require simulations of cardiovascular systems, such as medical mannequins, and in medical diagnostic systems. This approach is unique in that each cardiovascular model is developed from physiological measurements of an individual. Any differences between the modeled variables and the actual variables of an individual can subsequently be used for diagnosis. This approach also exploits sensor fusion applied to biomedical sensors. Sensor fusion optimizes the utilization of the sensors. The advantage of sensor fusion has been demonstrated in applications including control and diagnostics of mechanical and chemical processes.

  20. Enhancement and bias removal of optical coherence tomography images: An iterative approach with adaptive bilateral filtering.

    PubMed

    Sudeep, P V; Issac Niwas, S; Palanisamy, P; Rajan, Jeny; Xiaojun, Yu; Wang, Xianghong; Luo, Yuemei; Liu, Linbo

    2016-04-01

    Optical coherence tomography (OCT) has continually evolved and expanded as one of the most valuable routine tests in ophthalmology. However, noise (speckle) in the acquired images causes quality degradation of OCT images and makes it difficult to analyze the acquired images. In this paper, an iterative approach based on bilateral filtering is proposed for speckle reduction in multiframe OCT data. Gamma noise model is assumed for the observed OCT image. First, the adaptive version of the conventional bilateral filter is applied to enhance the multiframe OCT data and then the bias due to noise is reduced from each of the filtered frames. These unbiased filtered frames are then refined using an iterative approach. Finally, these refined frames are averaged to produce the denoised OCT image. Experimental results on phantom images and real OCT retinal images demonstrate the effectiveness of the proposed filter. PMID:26907572

  1. Adaptive MANET multipath routing algorithm based on the simulated annealing approach.

    PubMed

    Kim, Sungwook

    2014-01-01

    Mobile ad hoc network represents a system of wireless mobile nodes that can freely and dynamically self-organize network topologies without any preexisting communication infrastructure. Due to characteristics like temporary topology and absence of centralized authority, routing is one of the major issues in ad hoc networks. In this paper, a new multipath routing scheme is proposed by employing simulated annealing approach. The proposed metaheuristic approach can achieve greater and reciprocal advantages in a hostile dynamic real world network situation. Therefore, the proposed routing scheme is a powerful method for finding an effective solution into the conflict mobile ad hoc network routing problem. Simulation results indicate that the proposed paradigm adapts best to the variation of dynamic network situations. The average remaining energy, network throughput, packet loss probability, and traffic load distribution are improved by about 10%, 10%, 5%, and 10%, respectively, more than the existing schemes.

  2. Localization of IAA transporting tissue by tissue printing and autoradiography. [Coleus; maize

    SciTech Connect

    Mee-Rye Cha; Evans, M.L.; Hangarter, R.P. )

    1991-05-01

    Tissue printing on nitrocellulose membranes provides a useful technique for visualizing anatomical details of tissue morphology of cut ends of stem segments. Basal ends of Coleus stem and corn coleoptile segments that were transporting {sup 14}C-IAA were gently blotted onto DEAE-nitrocellulose for several minutes to allow {sup 14}C-IAA to efflux from the tissue. Because of the anion exchange properties of DEAE-nitrocellulose the {sup 14}C-IAA remains on the membrane at the point it leaves the transporting tissue. Autoradiography of the DEAE membrane allowed indirect visualization of the tissues preferentially involved in auxin transport. The authors observed that polar transport through the stem segments occurred primarily through or in association with vascular tissues. However, in Coleus stems, substantial amounts of the label appeared to move through the tissue by diffusion as well as by active transport.

  3. Pseudomonas savastanoi pv. savastanoi Contains Two iaaL Paralogs, One of Which Exhibits a Variable Number of a Trinucleotide (TAC) Tandem Repeat▿ †

    PubMed Central

    Matas, Isabel M.; Pérez-Martínez, Isabel; Quesada, José M.; Rodríguez-Herva, José J.; Penyalver, Ramón; Ramos, Cayo

    2009-01-01

    In this study, Pseudomonas savastanoi pv. savastanoi isolates were demonstrated to contain two iaaL paralogs, which are both chromosomally located in most strains. Comparative analysis of iaaL nucleotide sequences amplified from these two paralogs revealed that one paralog, iaaLPsn, is 100% identical to iaaL from P. savastanoi pv. nerii, while the other paralog, iaaLPsv, exhibited 93% identity to iaaL from Pseudomonas syringae pv. tomato (iaaLPto). A 3-nucleotide motif (TAC) comprised of 3 to 15 repeats, which remained stable after propagation of the strains in olive plants, was found in iaaLPsv. Based on the observed nucleotide sequence variations, a restriction fragment length polymorphism assay was developed that allowed differentiation among iaaLPsn, iaaLPsv, and iaaLPto. In addition, reverse transcriptase PCR on total RNA from P. savastanoi pv. savastanoi strains demonstrated that both iaaLPsv and iaaLPsn containing 14 or fewer TAC repeats are transcribed. Capillary electrophoresis analysis of PCR-amplified DNA fragments containing the TAC repeats from iaaLPsv allowed the differentiation of P. savastanoi pv. savastanoi isolates. PMID:19098222

  4. Integrating adaptive behaviour in large-scale flood risk assessments: an Agent-Based Modelling approach

    NASA Astrophysics Data System (ADS)

    Haer, Toon; Aerts, Jeroen

    2015-04-01

    Between 1998 and 2009, Europe suffered over 213 major damaging floods, causing 1126 deaths, displacing around half a million people. In this period, floods caused at least 52 billion euro in insured economic losses making floods the most costly natural hazard faced in Europe. In many low-lying areas, the main strategy to cope with floods is to reduce the risk of the hazard through flood defence structures, like dikes and levees. However, it is suggested that part of the responsibility for flood protection needs to shift to households and businesses in areas at risk, and that governments and insurers can effectively stimulate the implementation of individual protective measures. However, adaptive behaviour towards flood risk reduction and the interaction between the government, insurers, and individuals has hardly been studied in large-scale flood risk assessments. In this study, an European Agent-Based Model is developed including agent representatives for the administrative stakeholders of European Member states, insurers and reinsurers markets, and individuals following complex behaviour models. The Agent-Based Modelling approach allows for an in-depth analysis of the interaction between heterogeneous autonomous agents and the resulting (non-)adaptive behaviour. Existing flood damage models are part of the European Agent-Based Model to allow for a dynamic response of both the agents and the environment to changing flood risk and protective efforts. By following an Agent-Based Modelling approach this study is a first contribution to overcome the limitations of traditional large-scale flood risk models in which the influence of individual adaptive behaviour towards flood risk reduction is often lacking.

  5. Adaptive speed/position control of induction motor based on SPR approach

    NASA Astrophysics Data System (ADS)

    Lee, Hou-Tsan

    2014-11-01

    A sensorless speed/position tracking control scheme for induction motors is proposed subject to unknown load torque via adaptive strictly positive real (SPR) approach design. A special nonlinear coordinate transform is first provided to reform the dynamical model of the induction motor. The information on rotor fluxes can thus be derived from the dynamical model to decide on the proportion of input voltage in the d-q frame under the constraint of the maximum power transfer property of induction motors. Based on the SPR approach, the speed and position control objectives can be achieved. The proposed control scheme is to provide the speed/position control of induction motors while lacking the knowledge of some mechanical system parameters, such as the motor inertia, motor damping coefficient, and the unknown payload. The adaptive control technique is thus involved in the field oriented control scheme to deal with the unknown parameters. The thorough proof is derived to guarantee the stability of the speed and position of control systems of induction motors. Besides, numerical simulation and experimental results are also provided to validate the effectiveness of the proposed control scheme.

  6. Wavefront sensorless approaches to adaptive optics for in vivo fluorescence imaging of mouse retina

    NASA Astrophysics Data System (ADS)

    Wahl, Daniel J.; Bonora, Stefano; Mata, Oscar S.; Haunerland, Bengt K.; Zawadzki, Robert J.; Sarunic, Marinko V.; Jian, Yifan

    2016-03-01

    Adaptive optics (AO) is necessary to correct aberrations when imaging the mouse eye with high numerical aperture. In order to obtain cellular resolution, we have implemented wavefront sensorless adaptive optics for in vivo fluorescence imaging of mouse retina. Our approach includes a lens-based system and MEMS deformable mirror for aberration correction. The AO system was constructed with a reflectance channel for structural images and fluorescence channel for functional images. The structural imaging was used in real-time for navigation on the retina using landmarks such as blood vessels. We have also implemented a tunable liquid lens to select the retinal layer of interest at which to perform the optimization. At the desired location on the mouse retina, the optimization algorithm used the fluorescence image data to drive a modal hill-climbing algorithm using an intensity or sharpness image quality metric. The optimization requires ~30 seconds to complete a search up to the 20th Zernike mode. In this report, we have demonstrated the AO performance for high-resolution images of the capillaries in a fluorescence angiography. We have also made progress on an approach to AO with pupil segmentation as a possible sensorless technique suitable for small animal retinal imaging. Pupil segmentation AO was implemented on the same ophthalmic system and imaging performance was demonstrated on fluorescent beads with induced aberrations.

  7. Differentially Private Histogram Publication For Dynamic Datasets: An Adaptive Sampling Approach

    PubMed Central

    Li, Haoran; Jiang, Xiaoqian; Xiong, Li; Liu, Jinfei

    2016-01-01

    Differential privacy has recently become a de facto standard for private statistical data release. Many algorithms have been proposed to generate differentially private histograms or synthetic data. However, most of them focus on “one-time” release of a static dataset and do not adequately address the increasing need of releasing series of dynamic datasets in real time. A straightforward application of existing histogram methods on each snapshot of such dynamic datasets will incur high accumulated error due to the composibility of differential privacy and correlations or overlapping users between the snapshots. In this paper, we address the problem of releasing series of dynamic datasets in real time with differential privacy, using a novel adaptive distance-based sampling approach. Our first method, DSFT, uses a fixed distance threshold and releases a differentially private histogram only when the current snapshot is sufficiently different from the previous one, i.e., with a distance greater than a predefined threshold. Our second method, DSAT, further improves DSFT and uses a dynamic threshold adaptively adjusted by a feedback control mechanism to capture the data dynamics. Extensive experiments on real and synthetic datasets demonstrate that our approach achieves better utility than baseline methods and existing state-of-the-art methods. PMID:26973795

  8. Effect of IAA on in vitro growth and colonization of Nostoc in plant roots

    PubMed Central

    Hussain, Anwar; Shah, Syed T.; Rahman, Hazir; Irshad, Muhammad; Iqbal, Amjad

    2015-01-01

    Nostoc is widely known for its ability to fix atmospheric nitrogen and the establishment of symbiotic relationship with a wide range of plants from various taxonomic groups. Several strains of Nostoc produce phytohormones that promote growth of its plant partners. Nostoc OS-1 was therefore selected for study because of the presence of putative ipdC gene that encodes a key enzyme to produce Indole-3-acetic acid (IAA). The results indicated that both cellular and released IAA was found high with increasing incubation time and reached to a peak value (i.e., 21 pmol mg-1ch-a) on the third week as determined by UPLC-ESI-MS/MS. Also the Nostoc OS-1 strain efficiently colonized the roots and promoted the growth of rice as well as wheat under axenic conditions and induced ipdC gene that suggested the possible involvement of IAA in these phenotypes. To confirm the impact of IAA on root colonization efficiency and plant promoting phenotypes of Nostoc OS-1, an ipdC knockout mutant was generated by homologous recombinant method. The amount of releasing IAA, in vitro growth, root colonization, and plant promoting efficiency of the ipdC knockout mutant was observed significantly lower than wild type strain under axenic conditions. Importantly, these phenotypes were restored to wild-type levels when the ipdC knockout mutant was complemented with wild type ipdC gene. These results together suggested that ipdC and/or synthesized IAA of Nostoc OS-1 is required for its efficient root colonization and plant promoting activity. PMID:25699072

  9. Behavior Change Interventions to Improve the Health of Racial and Ethnic Minority Populations: A Tool Kit of Adaptation Approaches

    PubMed Central

    Davidson, Emma M; Liu, Jing Jing; Bhopal, Raj; White, Martin; Johnson, Mark RD; Netto, Gina; Wabnitz, Cecile; Sheikh, Aziz

    2013-01-01

    Context Adapting behavior change interventions to meet the needs of racial and ethnic minority populations has the potential to enhance their effectiveness in the target populations. But because there is little guidance on how best to undertake these adaptations, work in this field has proceeded without any firm foundations. In this article, we present our Tool Kit of Adaptation Approaches as a framework for policymakers, practitioners, and researchers interested in delivering behavior change interventions to ethnically diverse, underserved populations in the United Kingdom. Methods We undertook a mixed-method program of research on interventions for smoking cessation, increasing physical activity, and promoting healthy eating that had been adapted to improve salience and acceptability for African-, Chinese-, and South Asian–origin minority populations. This program included a systematic review (reported using PRISMA criteria), qualitative interviews, and a realist synthesis of data. Findings We compiled a richly informative data set of 161 publications and twenty-six interviews detailing the adaptation of behavior change interventions and the contexts in which they were undertaken. On the basis of these data, we developed our Tool Kit of Adaptation Approaches, which contains (1) a forty-six-item Typology of Adaptation Approaches; (2) a Pathway to Adaptation, which shows how to use the Typology to create a generic behavior change intervention; and (3) RESET, a decision tool that provides practical guidance on which adaptations to use in different contexts. Conclusions Our Tool Kit of Adaptation Approaches provides the first evidence-derived suite of materials to support the development, design, implementation, and reporting of health behavior change interventions for minority groups. The Tool Kit now needs prospective, empirical evaluation in a range of intervention and population settings. PMID:24320170

  10. Growth Promotion of Yunnan Pine Early Seedlings in Response to Foliar Application of IAA and IBA

    PubMed Central

    Xu, Yulan; Zhang, Yuemin; Li, Yunfei; Li, Genqian; Liu, Daiyi; Zhao, Minchong; Cai, Nianhui

    2012-01-01

    A field experiment was conducted using a 3 × 3 orthogonal regression design to explore the growth promotion of one-year-old Yunnan pine seedlings (Pinus yunnanensis Franch.) in response to foliar application of IAA (indole-3-acetic acid) at rates of 0, 200 and 400 mg·L−1 and IBA (indole-3-butyric acid) at rates of 0, 200 and 400 mg·L−1 in order to promote the growth during the seedlings’ early stage. The experiment was conducted at the Lufeng Village Forest Farm of Yiliang County in Kunming, Yunnan, China. The results showed that IAA and IBA were effective in growth promotion of Yunnan pine seedlings. The response of both growth increment and biomass accumulation to the concentration of IAA and IBA can be modeled using a bivariate surface response, and each growth index had a peak value. Growth indexes increased with the increase of the dosage of photohormones before reaching a peak value, and then decreased. The different growth indexes had various responses to the concentrations and ratio of IAA and IBA. The foliar application of IAA in combination with IBA showed the largest improvement on the biomass of the needles, followed by stems and roots. The higher ratio of IAA promoted stem diameter growth, root system development and biomass accumulation in the needles, while a higher ratio of IBA contributed to height growth and biomass accumulation in the stem. Based on the auxin effect equations on the different growth indexes and surface response, the optimum concentrations and the (IAA:IBA) ratios can be obtained. The optimum concentrations of IAA and IBA were 167 and 186, 310 and 217, 193 and 159, 191 and 221, and 206 and 186 mg·L−1, with corresponding ratios of 1:1.11, 1:0.70, 1:0.82, 1:1.15 and 1:0.90, respectively, at the maximum seedling height and collar diameter growth as well as biomass accumulation at the root, stem and needle. The above growth indexes were 22.00%, 79.80%, 48.65%, 82.20% and 107.00% higher than the control treatment. PMID

  11. Integrated approaches to natural resources management in practice: the catalyzing role of National Adaptation Programmes for Action.

    PubMed

    Stucki, Virpi; Smith, Mark

    2011-06-01

    The relationship of forests in water quantity and quality has been debated during the past years. At the same time, focus on climate change has increased interest in ecosystem restoration as a means for adaptation. Climate change might become one of the key drivers pushing integrated approaches for natural resources management into practice. The National Adaptation Programme of Action (NAPA) is an initiative agreed under the UN Framework Convention on Climate Change. An analysis was done to find out how widely ecosystem restoration and integrated approaches have been incorporated into NAPA priority adaptation projects. The data show that that the NAPAs can be seen as potentially important channel for operationalizing various integrated concepts. Key challenge is to implement the NAPA projects. The amount needed to implement the NAPA projects aiming at ecosystem restoration using integrated approaches presents only 0.7% of the money pledged in Copenhagen for climate change adaptation.

  12. Solution structure of the PsIAA4 oligomerization domain reveals interaction modes for transcription factors in early auxin response.

    PubMed

    Dinesh, Dhurvas Chandrasekaran; Kovermann, Michael; Gopalswamy, Mohanraj; Hellmuth, Antje; Calderón Villalobos, Luz Irina A; Lilie, Hauke; Balbach, Jochen; Abel, Steffen

    2015-05-12

    The plant hormone auxin activates primary response genes by facilitating proteolytic removal of auxin/indole-3-acetic acid (AUX/IAA)-inducible repressors, which directly bind to transcriptional auxin response factors (ARF). Most AUX/IAA and ARF proteins share highly conserved C-termini mediating homotypic and heterotypic interactions within and between both protein families. The high-resolution NMR structure of C-terminal domains III and IV of the AUX/IAA protein PsIAA4 from pea (Pisum sativum) revealed a globular ubiquitin-like β-grasp fold with homologies to the Phox and Bem1p (PB1) domain. The PB1 domain of wild-type PsIAA4 features two distinct surface patches of oppositely charged amino acid residues, mediating front-to-back multimerization via electrostatic interactions. Mutations of conserved basic or acidic residues on either face suppressed PsIAA4 PB1 homo-oligomerization in vitro and confirmed directional interaction of full-length PsIAA4 in vivo (yeast two-hybrid system). Mixing of oppositely mutated PsIAA4 PB1 monomers enabled NMR mapping of the negatively charged interface of the reconstituted PsIAA4 PB1 homodimer variant, whose stoichiometry (1:1) and equilibrium binding constant (KD ∼ 6.4 μM) were determined by isothermal titration calorimetry. In silico protein-protein docking studies based on NMR and yeast interaction data derived a model of the PsIAA4 PB1 homodimer, which is comparable with other PB1 domain dimers, but indicated considerable differences between the homodimeric interfaces of AUX/IAA and ARF PB1 domains. Our study provides an impetus for elucidating the molecular determinants that confer specificity to complex protein-protein interaction circuits between members of the two central families of transcription factors important to the regulation of auxin-responsive gene expression. PMID:25918389

  13. Solution structure of the PsIAA4 oligomerization domain reveals interaction modes for transcription factors in early auxin response.

    PubMed

    Dinesh, Dhurvas Chandrasekaran; Kovermann, Michael; Gopalswamy, Mohanraj; Hellmuth, Antje; Calderón Villalobos, Luz Irina A; Lilie, Hauke; Balbach, Jochen; Abel, Steffen

    2015-05-12

    The plant hormone auxin activates primary response genes by facilitating proteolytic removal of auxin/indole-3-acetic acid (AUX/IAA)-inducible repressors, which directly bind to transcriptional auxin response factors (ARF). Most AUX/IAA and ARF proteins share highly conserved C-termini mediating homotypic and heterotypic interactions within and between both protein families. The high-resolution NMR structure of C-terminal domains III and IV of the AUX/IAA protein PsIAA4 from pea (Pisum sativum) revealed a globular ubiquitin-like β-grasp fold with homologies to the Phox and Bem1p (PB1) domain. The PB1 domain of wild-type PsIAA4 features two distinct surface patches of oppositely charged amino acid residues, mediating front-to-back multimerization via electrostatic interactions. Mutations of conserved basic or acidic residues on either face suppressed PsIAA4 PB1 homo-oligomerization in vitro and confirmed directional interaction of full-length PsIAA4 in vivo (yeast two-hybrid system). Mixing of oppositely mutated PsIAA4 PB1 monomers enabled NMR mapping of the negatively charged interface of the reconstituted PsIAA4 PB1 homodimer variant, whose stoichiometry (1:1) and equilibrium binding constant (KD ∼ 6.4 μM) were determined by isothermal titration calorimetry. In silico protein-protein docking studies based on NMR and yeast interaction data derived a model of the PsIAA4 PB1 homodimer, which is comparable with other PB1 domain dimers, but indicated considerable differences between the homodimeric interfaces of AUX/IAA and ARF PB1 domains. Our study provides an impetus for elucidating the molecular determinants that confer specificity to complex protein-protein interaction circuits between members of the two central families of transcription factors important to the regulation of auxin-responsive gene expression.

  14. Adaptive Management

    EPA Science Inventory

    Adaptive management is an approach to natural resource management that emphasizes learning through management where knowledge is incomplete, and when, despite inherent uncertainty, managers and policymakers must act. Unlike a traditional trial and error approach, adaptive managem...

  15. A User-Driven and Data-Driven Approach for Supporting Teachers in Reflection and Adaptation of Adaptive Tutorials

    ERIC Educational Resources Information Center

    Ben-Naim, Dror; Bain, Michael; Marcus, Nadine

    2009-01-01

    It has been recognized that in order to drive Intelligent Tutoring Systems (ITSs) into mainstream use by the teaching community, it is essential to support teachers through the entire ITS process: Design, Development, Deployment, Reflection and Adaptation. Although research has been done on supporting teachers through design to deployment of ITSs,…

  16. Adaptive Methods within a Sequential Bayesian Approach for Structural Health Monitoring

    NASA Astrophysics Data System (ADS)

    Huff, Daniel W.

    computational burden is decreased significantly and the number of possible observation modes can be increased. Using sensor measurements from real experiments, the overall sequential Bayesian estimation approach, with the adaptive capability of varying the state dynamics and observation modes, is demonstrated for tracking crack damage.

  17. An adaptive neural swarm approach for intrusion defense in ad hoc networks

    NASA Astrophysics Data System (ADS)

    Cannady, James

    2011-06-01

    Wireless sensor networks (WSN) and mobile ad hoc networks (MANET) are being increasingly deployed in critical applications due to the flexibility and extensibility of the technology. While these networks possess numerous advantages over traditional wireless systems in dynamic environments they are still vulnerable to many of the same types of host-based and distributed attacks common to those systems. Unfortunately, the limited power and bandwidth available in WSNs and MANETs, combined with the dynamic connectivity that is a defining characteristic of the technology, makes it extremely difficult to utilize traditional intrusion detection techniques. This paper describes an approach to accurately and efficiently detect potentially damaging activity in WSNs and MANETs. It enables the network as a whole to recognize attacks, anomalies, and potential vulnerabilities in a distributive manner that reflects the autonomic processes of biological systems. Each component of the network recognizes activity in its local environment and then contributes to the overall situational awareness of the entire system. The approach utilizes agent-based swarm intelligence to adaptively identify potential data sources on each node and on adjacent nodes throughout the network. The swarm agents then self-organize into modular neural networks that utilize a reinforcement learning algorithm to identify relevant behavior patterns in the data without supervision. Once the modular neural networks have established interconnectivity both locally and with neighboring nodes the analysis of events within the network can be conducted collectively in real-time. The approach has been shown to be extremely effective in identifying distributed network attacks.

  18. Characterization of GM events by insert knowledge adapted re-sequencing approaches.

    PubMed

    Yang, Litao; Wang, Congmao; Holst-Jensen, Arne; Morisset, Dany; Lin, Yongjun; Zhang, Dabing

    2013-01-01

    Detection methods and data from molecular characterization of genetically modified (GM) events are needed by stakeholders of public risk assessors and regulators. Generally, the molecular characteristics of GM events are incomprehensively revealed by current approaches and biased towards detecting transformation vector derived sequences. GM events are classified based on available knowledge of the sequences of vectors and inserts (insert knowledge). Herein we present three insert knowledge-adapted approaches for characterization GM events (TT51-1 and T1c-19 rice as examples) based on paired-end re-sequencing with the advantages of comprehensiveness, accuracy, and automation. The comprehensive molecular characteristics of two rice events were revealed with additional unintended insertions comparing with the results from PCR and Southern blotting. Comprehensive transgene characterization of TT51-1 and T1c-19 is shown to be independent of a priori knowledge of the insert and vector sequences employing the developed approaches. This provides an opportunity to identify and characterize also unknown GM events. PMID:24088728

  19. Seeking mathematics success for college students: a randomized field trial of an adapted approach

    NASA Astrophysics Data System (ADS)

    Gula, Taras; Hoessler, Carolyn; Maciejewski, Wes

    2015-11-01

    Many students enter the Canadian college system with insufficient mathematical ability and leave the system with little improvement. Those students who enter with poor mathematics ability typically take a developmental mathematics course as their first and possibly only mathematics course. The educational experiences that comprise a developmental mathematics course vary widely and are, too often, ineffective at improving students' ability. This trend is concerning, since low mathematics ability is known to be related to lower rates of success in subsequent courses. To date, little attention has been paid to the selection of an instructional approach to consistently apply across developmental mathematics courses. Prior research suggests that an appropriate instructional method would involve explicit instruction and practising mathematical procedures linked to a mathematical concept. This study reports on a randomized field trial of a developmental mathematics approach at a college in Ontario, Canada. The new approach is an adaptation of the JUMP Math program, an explicit instruction method designed for primary and secondary school curriculae, to the college learning environment. In this study, a subset of courses was assigned to JUMP Math and the remainder was taught in the same style as in the previous years. We found consistent, modest improvement in the JUMP Math sections compared to the non-JUMP sections, after accounting for potential covariates. The findings from this randomized field trial, along with prior research on effective education for developmental mathematics students, suggest that JUMP Math is a promising way to improve college student outcomes.

  20. An efficient and self-adapted approach to the sharpening of color images.

    PubMed

    Kau, Lih-Jen; Lee, Tien-Lin

    2013-01-01

    An efficient approach to the sharpening of color images is proposed in this paper. For this, the image to be sharpened is first transformed to the HSV color model, and then only the channel of Value will be used for the process of sharpening while the other channels are left unchanged. We then apply a proposed edge detector and low-pass filter to the channel of Value to pick out pixels around boundaries. After that, those pixels detected as around edges or boundaries are adjusted so that the boundary can be sharpened, and those nonedge pixels are kept unaltered. The increment or decrement magnitude that is to be added to those edge pixels is determined in an adaptive manner based on global statistics of the image and local statistics of the pixel to be sharpened. With the proposed approach, the discontinuities can be highlighted while most of the original information contained in the image can be retained. Finally, the adjusted channel of Value and that of Hue and Saturation will be integrated to get the sharpened color image. Extensive experiments on natural images will be given in this paper to highlight the effectiveness and efficiency of the proposed approach. PMID:24348136

  1. The adaptive approach for storage assignment by mining data of warehouse management system for distribution centres

    NASA Astrophysics Data System (ADS)

    Ming-Huang Chiang, David; Lin, Chia-Ping; Chen, Mu-Chen

    2011-05-01

    Among distribution centre operations, order picking has been reported to be the most labour-intensive activity. Sophisticated storage assignment policies adopted to reduce the travel distance of order picking have been explored in the literature. Unfortunately, previous research has been devoted to locating entire products from scratch. Instead, this study intends to propose an adaptive approach, a Data Mining-based Storage Assignment approach (DMSA), to find the optimal storage assignment for newly delivered products that need to be put away when there is vacant shelf space in a distribution centre. In the DMSA, a new association index (AIX) is developed to evaluate the fitness between the put away products and the unassigned storage locations by applying association rule mining. With AIX, the storage location assignment problem (SLAP) can be formulated and solved as a binary integer programming. To evaluate the performance of DMSA, a real-world order database of a distribution centre is obtained and used to compare the results from DMSA with a random assignment approach. It turns out that DMSA outperforms random assignment as the number of put away products and the proportion of put away products with high turnover rates increase.

  2. Adaptation policies to increase terrestrial ecosystem resilience. Potential utility of a multicriteria approach

    SciTech Connect

    de Bremond, Ariane; Engle, Nathan L.

    2014-01-30

    Climate change is rapidly undermining terrestrial ecosystem resilience and capacity to continue providing their services to the benefit of humanity and nature. Because of the importance of terrestrial ecosystems to human well-being and supporting services, decision makers throughout the world are busy creating policy responses that secure multiple development and conservation objectives- including that of supporting terrestrial ecosystem resilience in the context of climate change. This article aims to advance analyses on climate policy evaluation and planning in the area of terrestrial ecosystem resilience by discussing adaptation policy options within the ecology-economy-social nexus. The paper evaluates these decisions in the realm of terrestrial ecosystem resilience and evaluates the utility of a set of criteria, indicators, and assessment methods, proposed by a new conceptual multi-criteria framework for pro-development climate policy and planning developed by the United Nations Environment Programme. Potential applications of a multicriteria approach to climate policy vis-A -vis terrestrial ecosystems are then explored through two hypothetical case study examples. The paper closes with a brief discussion of the utility of the multi-criteria approach in the context of other climate policy evaluation approaches, considers lessons learned as a result efforts to evaluate climate policy in the realm of terrestrial ecosystems, and reiterates the role of ecosystem resilience in creating sound policies and actions that support the integration of climate change and development goals.

  3. Characterization of GM events by insert knowledge adapted re-sequencing approaches

    PubMed Central

    Yang, Litao; Wang, Congmao; Holst-Jensen, Arne; Morisset, Dany; Lin, Yongjun; Zhang, Dabing

    2013-01-01

    Detection methods and data from molecular characterization of genetically modified (GM) events are needed by stakeholders of public risk assessors and regulators. Generally, the molecular characteristics of GM events are incomprehensively revealed by current approaches and biased towards detecting transformation vector derived sequences. GM events are classified based on available knowledge of the sequences of vectors and inserts (insert knowledge). Herein we present three insert knowledge-adapted approaches for characterization GM events (TT51-1 and T1c-19 rice as examples) based on paired-end re-sequencing with the advantages of comprehensiveness, accuracy, and automation. The comprehensive molecular characteristics of two rice events were revealed with additional unintended insertions comparing with the results from PCR and Southern blotting. Comprehensive transgene characterization of TT51-1 and T1c-19 is shown to be independent of a priori knowledge of the insert and vector sequences employing the developed approaches. This provides an opportunity to identify and characterize also unknown GM events. PMID:24088728

  4. Data-adaptive unfolding of nuclear excitation spectra: a time-series approach

    NASA Astrophysics Data System (ADS)

    Torres Vargas, G.; Fossion, R.; Velázquez, V.; López Vieyra, J. C.

    2014-03-01

    A common problem in the statistical characterization of the excitation spectrum of quantum systems is the adequate separation of global system-dependent properties from the local fluctuations that are universal. In this process, called unfolding, the functional form to describe the global behaviour is often imposed externally on the data and can introduce arbitrarities in the statistical results. In this contribution, we show that a quantum excitation spectrum can readily be interpreted as a time series, before any previous unfolding. An advantage of the time-series approach is that specialized methods such as Singular Spectrum Analysis (SSA) can be used to perform the unfolding procedure in a data-adaptive way. We will show how SSA separates the components that describe the global properties from the components that describe the local fluctuations. The partial variances, associated with the fluctuations, follow a definite power law that distinguishes between soft and rigid excitation spectra. The data-adaptive fluctuation and trend components can be used to reconstruct customary fluctuation measures without ambiguities or artifacts introduced by an arbitrary unfolding, and also define the global level density of the excitation spectrum. The method is applied to nuclear shell-model calculations for 48Ca, using a realistic force and Two-Body Random Ensemble (TBRE) interactions. We show that the statistical results are very robust against a variation in the parameters of the SSA method.

  5. Thermal genetic adaptation in the water flea Daphnia and its impact: an evolving metacommunity approach.

    PubMed

    De Meester, Luc; Van Doorslaer, Wendy; Geerts, Aurora; Orsini, Luisa; Stoks, Robby

    2011-11-01

    Genetic adaptation to temperature change can impact responses of populations and communities to global warming. Here we integrate previously published results on experimental evolution trials with follow-up experiments involving the water flea Daphnia as a model system. Our research shows (1) the capacity of natural populations of this species to genetically adapt to changes in temperature in a time span of months to years, (2) the context-dependence of these genetic changes, emphasizing the role of ecology and community composition on evolutionary responses to climatic change, and (3) the impact of micro-evolutionary changes on immigration success of preadapted genotypes. Our study involves (1) experimental evolution trials in the absence and presence of the community of competitors, predators, and parasites, (2) life-table and competition experiments to assess the fitness consequences of micro-evolution, and (3) competition experiments with putative immigrant genotypes. We use these observations as building blocks of an evolving metacommunity to understand biological responses to climatic change. This approach integrates both local and regional responses at both the population and community levels. Finally, we provide an outline of current gaps in knowledge and suggest fruitful avenues for future research.

  6. Neural network approach to continuous-time direct adaptive optimal control for partially unknown nonlinear systems.

    PubMed

    Vrabie, Draguna; Lewis, Frank

    2009-04-01

    In this paper we present in a continuous-time framework an online approach to direct adaptive optimal control with infinite horizon cost for nonlinear systems. The algorithm converges online to the optimal control solution without knowledge of the internal system dynamics. Closed-loop dynamic stability is guaranteed throughout. The algorithm is based on a reinforcement learning scheme, namely Policy Iterations, and makes use of neural networks, in an Actor/Critic structure, to parametrically represent the control policy and the performance of the control system. The two neural networks are trained to express the optimal controller and optimal cost function which describes the infinite horizon control performance. Convergence of the algorithm is proven under the realistic assumption that the two neural networks do not provide perfect representations for the nonlinear control and cost functions. The result is a hybrid control structure which involves a continuous-time controller and a supervisory adaptation structure which operates based on data sampled from the plant and from the continuous-time performance dynamics. Such control structure is unlike any standard form of controllers previously seen in the literature. Simulation results, obtained considering two second-order nonlinear systems, are provided.

  7. Identification of novel serum peptide biomarkers for high-altitude adaptation: a comparative approach

    NASA Astrophysics Data System (ADS)

    Yang, Juan; Li, Wenhua; Liu, Siyuan; Yuan, Dongya; Guo, Yijiao; Jia, Cheng; Song, Tusheng; Huang, Chen

    2016-05-01

    We aimed to identify serum biomarkers for screening individuals who could adapt to high-altitude hypoxia at sea level. HHA (high-altitude hypoxia acclimated; n = 48) and HHI (high-altitude hypoxia illness; n = 48) groups were distinguished at high altitude, routine blood tests were performed for both groups at high altitude and at sea level. Serum biomarkers were identified by comparing serum peptidome profiling between HHI and HHA groups collected at sea level. Routine blood tests revealed the concentration of hemoglobin and red blood cells were significantly higher in HHI than in HHA at high altitude. Serum peptidome profiling showed that ten significantly differentially expressed peaks between HHA and HHI at sea level. Three potential serum peptide peaks (m/z values: 1061.91, 1088.33, 4057.63) were further sequence identified as regions of the inter-α trypsin inhibitor heavy chain H4 fragment (ITIH4 347–356), regions of the inter-α trypsin inhibitor heavy chain H1 fragment (ITIH1 205–214), and isoform 1 of fibrinogen α chain precursor (FGA 588–624). Expression of their full proteins was also tested by ELISA in HHA and HHI samples collected at sea level. Our study provided a novel approach for identifying potential biomarkers for screening people at sea level who can adapt to high altitudes.

  8. Neural network approach to continuous-time direct adaptive optimal control for partially unknown nonlinear systems.

    PubMed

    Vrabie, Draguna; Lewis, Frank

    2009-04-01

    In this paper we present in a continuous-time framework an online approach to direct adaptive optimal control with infinite horizon cost for nonlinear systems. The algorithm converges online to the optimal control solution without knowledge of the internal system dynamics. Closed-loop dynamic stability is guaranteed throughout. The algorithm is based on a reinforcement learning scheme, namely Policy Iterations, and makes use of neural networks, in an Actor/Critic structure, to parametrically represent the control policy and the performance of the control system. The two neural networks are trained to express the optimal controller and optimal cost function which describes the infinite horizon control performance. Convergence of the algorithm is proven under the realistic assumption that the two neural networks do not provide perfect representations for the nonlinear control and cost functions. The result is a hybrid control structure which involves a continuous-time controller and a supervisory adaptation structure which operates based on data sampled from the plant and from the continuous-time performance dynamics. Such control structure is unlike any standard form of controllers previously seen in the literature. Simulation results, obtained considering two second-order nonlinear systems, are provided. PMID:19362449

  9. Formation tracker design of multiple mobile robots with wheel perturbations: adaptive output-feedback approach

    NASA Astrophysics Data System (ADS)

    Yoo, Sung Jin

    2016-11-01

    This paper presents a theoretical design approach for output-feedback formation tracking of multiple mobile robots under wheel perturbations. It is assumed that these perturbations are unknown and the linear and angular velocities of the robots are unmeasurable. First, adaptive state observers for estimating unmeasurable velocities of the robots are developed under the robots' kinematics and dynamics including wheel perturbation effects. Then, we derive a virtual-structure-based formation tracker scheme according to the observer dynamic surface design procedure. The main difficulty of the output-feedback control design is to manage the coupling problems between unmeasurable velocities and unknown wheel perturbation effects. These problems are avoided by using the adaptive technique and the function approximation property based on fuzzy logic systems. From the Lyapunov stability analysis, it is shown that point tracking errors of each robot and synchronisation errors for the desired formation converge to an adjustable neighbourhood of the origin, while all signals in the controlled closed-loop system are semiglobally uniformly ultimately bounded.

  10. Supportive Communication to Facilitate Chinese Patients' Adaptation to a Permanent Colostomy: A Qualitative Case Study Approach.

    PubMed

    Tao, Hui; Songwathana, Praneed; Isaramalai, Sang-Arun; Wang, Qingxi

    2016-01-01

    This study, which is a part of action research, aims to explore how supportive communication can impact individuals' adaptation to a permanent colostomy in a Chinese cultural context. Two Chinese rectal cancer patients with complexity and difficulty in living with a permanent colostomy were selected using a qualitative case study approach. The researcher (H.T.) interacted with the participants along their journey from the preoperative period until the third postoperative month after discharge via face-to-face or telephone interviews. Content analysis was applied. Supportive communication was characterized by "communication as a supportive tool," which consisted of 4 elements: respect, description, empathy, and empowerment. The nursing strategies included (1) developing a collaborative relationship with patients and families; (2) understanding patients' concerns and problems; (3) discussing potential solutions; (4) encouraging patients to take action; (5) bringing out emotional expression; (6) normalizing negative emotions; and (7) protecting hope. The findings of this study informed that supportive communication is a valuable tool for nurses to provide informational and emotional support to Chinese patients in order to enhance their adaptation to living with a permanent colostomy. Developing an operational manual to enhance supportive communication for patients with colostomy is suggested. PMID:27684635

  11. Requirements and approaches to adapting laser writers for fabrication of gray-scale masks

    NASA Astrophysics Data System (ADS)

    Korolkov, Victor P.; Shimansky, Ruslan; Poleshchuk, Alexander G.; Cherkashin, Vadim V.; Kharissov, Andrey A.; Denk, Dmitry

    2001-11-01

    The photolithography using gray-scale masks (GSM) with multilevel transmittance is now one of promising ways for manufacturing of high efficiency diffractive optical elements and microoptics. Such masks can be most effectively fabricated by laser or electron-beam writers on materials with a transmittance changing under influence of high-energy beams. The basic requirements for adaptation of existing and developed scanning laser writers are formulated. These systems create an image by continuous movement of a writing beam along one coordinate and overlapping of adjacent written tracks along another coordinate. Several problems must be solved at the GSM manufacturing: the calibration of the influence of the laser beam on a recording material without transferring the gray-scale structure into photoresist; the transmittance at the current exposed pixel depends on surrounding structures generated before recording of the current track and a character of the laser beam power modulation; essential increasing of the computed data in comparison with binary elements. The offered solutions are based on the results of investigations of the materials with variable transmittance (LDW-glass, a-Si film) and takes into account the specificity of diffractive blazed microstructures. The reduction of data amount for fabrication of multi-level DOEs is effectively performed using offered vector-gradient data format, which is based on piecewise-linear approximation of phase profile. The presented approaches to adaptation of laser writers are realized in software and hardware, and they allow to solve the basic problems of manufacturing GSMs.

  12. Analytic approach to co-evolving dynamics in complex networks: dissatisfied adaptive snowdrift game

    NASA Astrophysics Data System (ADS)

    Gräser, Oliver; Xu, Chen; Hui, P. M.

    2011-08-01

    We investigate the formulation of mean-field (MF) approaches for co-evolving dynamic model systems, focusing on the accuracy and validity of different schemes in closing MF equations. Within the context of a recently introduced co-evolutionary snowdrift game in which rational adaptive actions are driven by dissatisfaction in the payoff, we introduce a method to test the validity of closure schemes and analyse the shortcomings of previous schemes. A previous scheme suitable for adaptive epidemic models is shown to be invalid for the model studied here. A binomial-style closure scheme that significantly improves upon the previous schemes is introduced. Fixed-point analysis of the MF equations not only explains the numerical observed transition between a connected state with suppressed cooperation and a highly cooperative disconnected state, but also reveals a previously undetected connected state that exhibits the unusual behaviour of decreasing cooperation as the temptation for uncooperative action drops. We proposed a procedure for selecting proper initial conditions to realize the unusual state in numerical simulations. The effects of the mean number of connections that an agent carries are also studied.

  13. Identification of novel serum peptide biomarkers for high-altitude adaptation: a comparative approach.

    PubMed

    Yang, Juan; Li, Wenhua; Liu, Siyuan; Yuan, Dongya; Guo, Yijiao; Jia, Cheng; Song, Tusheng; Huang, Chen

    2016-01-01

    We aimed to identify serum biomarkers for screening individuals who could adapt to high-altitude hypoxia at sea level. HHA (high-altitude hypoxia acclimated; n = 48) and HHI (high-altitude hypoxia illness; n = 48) groups were distinguished at high altitude, routine blood tests were performed for both groups at high altitude and at sea level. Serum biomarkers were identified by comparing serum peptidome profiling between HHI and HHA groups collected at sea level. Routine blood tests revealed the concentration of hemoglobin and red blood cells were significantly higher in HHI than in HHA at high altitude. Serum peptidome profiling showed that ten significantly differentially expressed peaks between HHA and HHI at sea level. Three potential serum peptide peaks (m/z values: 1061.91, 1088.33, 4057.63) were further sequence identified as regions of the inter-α trypsin inhibitor heavy chain H4 fragment (ITIH4 347-356), regions of the inter-α trypsin inhibitor heavy chain H1 fragment (ITIH1 205-214), and isoform 1 of fibrinogen α chain precursor (FGA 588-624). Expression of their full proteins was also tested by ELISA in HHA and HHI samples collected at sea level. Our study provided a novel approach for identifying potential biomarkers for screening people at sea level who can adapt to high altitudes.

  14. A new adaptive multiple modelling approach for non-linear and non-stationary systems

    NASA Astrophysics Data System (ADS)

    Chen, Hao; Gong, Yu; Hong, Xia

    2016-07-01

    This paper proposes a novel adaptive multiple modelling algorithm for non-linear and non-stationary systems. This simple modelling paradigm comprises K candidate sub-models which are all linear. With data available in an online fashion, the performance of all candidate sub-models are monitored based on the most recent data window, and M best sub-models are selected from the K candidates. The weight coefficients of the selected sub-model are adapted via the recursive least square (RLS) algorithm, while the coefficients of the remaining sub-models are unchanged. These M model predictions are then optimally combined to produce the multi-model output. We propose to minimise the mean square error based on a recent data window, and apply the sum to one constraint to the combination parameters, leading to a closed-form solution, so that maximal computational efficiency can be achieved. In addition, at each time step, the model prediction is chosen from either the resultant multiple model or the best sub-model, whichever is the best. Simulation results are given in comparison with some typical alternatives, including the linear RLS algorithm and a number of online non-linear approaches, in terms of modelling performance and time consumption.

  15. Oligomerization of SCFTIR1 Is Essential for Aux/IAA Degradation and Auxin Signaling in Arabidopsis.

    PubMed

    Dezfulian, Mohammad H; Jalili, Espanta; Roberto, Don Karl A; Moss, Britney L; Khoo, Kerry; Nemhauser, Jennifer L; Crosby, William L

    2016-09-01

    The phytohormone auxin is a key regulator of plant growth and development. Molecular studies in Arabidopsis have shown that auxin perception and signaling is mediated via TIR1/AFB-Aux/IAA co-receptors that assemble as part of the SCFTIR1/AFB E3 ubiquitin-ligase complex and direct the auxin-regulated degradation of Aux/IAA transcriptional repressors. Despite the importance of auxin signaling, little is known about the functional regulation of the TIR1/AFB receptor family. Here we show that TIR1 can oligomerize in planta via a set of spatially clustered amino acid residues. While none of the residues identified reside in the interaction interface of the TIR1-Aux/IAA degron, they nonetheless regulate the binding of TIR1 to Aux/IAA substrate proteins and their subsequent degradation in vivo as an essential aspect of auxin signaling. We propose oligomerization of TIR1 as a novel regulatory mechanism in the regulation of auxin-mediated plant patterning and development.

  16. Oligomerization of SCFTIR1 Is Essential for Aux/IAA Degradation and Auxin Signaling in Arabidopsis

    PubMed Central

    Dezfulian, Mohammad H.; Jalili, Espanta; Khoo, Kerry; Nemhauser, Jennifer L.; Crosby, William L.

    2016-01-01

    The phytohormone auxin is a key regulator of plant growth and development. Molecular studies in Arabidopsis have shown that auxin perception and signaling is mediated via TIR1/AFB–Aux/IAA co-receptors that assemble as part of the SCFTIR1/AFB E3 ubiquitin-ligase complex and direct the auxin-regulated degradation of Aux/IAA transcriptional repressors. Despite the importance of auxin signaling, little is known about the functional regulation of the TIR1/AFB receptor family. Here we show that TIR1 can oligomerize in planta via a set of spatially clustered amino acid residues. While none of the residues identified reside in the interaction interface of the TIR1-Aux/IAA degron, they nonetheless regulate the binding of TIR1 to Aux/IAA substrate proteins and their subsequent degradation in vivo as an essential aspect of auxin signaling. We propose oligomerization of TIR1 as a novel regulatory mechanism in the regulation of auxin-mediated plant patterning and development. PMID:27618443

  17. Oligomerization of SCFTIR1 Is Essential for Aux/IAA Degradation and Auxin Signaling in Arabidopsis.

    PubMed

    Dezfulian, Mohammad H; Jalili, Espanta; Roberto, Don Karl A; Moss, Britney L; Khoo, Kerry; Nemhauser, Jennifer L; Crosby, William L

    2016-09-01

    The phytohormone auxin is a key regulator of plant growth and development. Molecular studies in Arabidopsis have shown that auxin perception and signaling is mediated via TIR1/AFB-Aux/IAA co-receptors that assemble as part of the SCFTIR1/AFB E3 ubiquitin-ligase complex and direct the auxin-regulated degradation of Aux/IAA transcriptional repressors. Despite the importance of auxin signaling, little is known about the functional regulation of the TIR1/AFB receptor family. Here we show that TIR1 can oligomerize in planta via a set of spatially clustered amino acid residues. While none of the residues identified reside in the interaction interface of the TIR1-Aux/IAA degron, they nonetheless regulate the binding of TIR1 to Aux/IAA substrate proteins and their subsequent degradation in vivo as an essential aspect of auxin signaling. We propose oligomerization of TIR1 as a novel regulatory mechanism in the regulation of auxin-mediated plant patterning and development. PMID:27618443

  18. An adaptive learning approach for 3-D surface reconstruction from point clouds.

    PubMed

    Junior, Agostinho de Medeiros Brito; Neto, Adrião Duarte Dória; de Melo, Jorge Dantas; Goncalves, Luiz Marcos Garcia

    2008-06-01

    In this paper, we propose a multiresolution approach for surface reconstruction from clouds of unorganized points representing an object surface in 3-D space. The proposed method uses a set of mesh operators and simple rules for selective mesh refinement, with a strategy based on Kohonen's self-organizing map (SOM). Basically, a self-adaptive scheme is used for iteratively moving vertices of an initial simple mesh in the direction of the set of points, ideally the object boundary. Successive refinement and motion of vertices are applied leading to a more detailed surface, in a multiresolution, iterative scheme. Reconstruction was experimented on with several point sets, including different shapes and sizes. Results show generated meshes very close to object final shapes. We include measures of performance and discuss robustness.

  19. Event-driven approach of layered multicast to network adaptation in RED-based IP networks

    NASA Astrophysics Data System (ADS)

    Nahm, Kitae; Li, Qing; Kuo, C.-C. J.

    2003-11-01

    In this work, we investigate the congestion control problem for layered video multicast in IP networks of active queue management (AQM) using a simple random early detection (RED) queue model. AQM support from networks improves the visual quality of video streaming but makes network adaptation more di+/-cult for existing layered video multicast proticols that use the event-driven timer-based approach. We perform a simplified analysis on the response of the RED algorithm to burst traffic. The analysis shows that the primary problem lies in the weak correlation between the network feedback and the actual network congestion status when the RED queue is driven by burst traffic. Finally, a design guideline of the layered multicast protocol is proposed to overcome this problem.

  20. Spin Adapted versus Broken Symmetry Approaches in the Description of Magnetic Coupling in Heterodinuclear Complexes.

    PubMed

    Costa, Ramon; Valero, Rosendo; Reta Mañeru, Daniel; Moreira, Ibério de P R; Illas, Francesc

    2015-03-10

    The performance of a series of wave function and density functional theory based methods in predicting the magnetic coupling constant of a family of heterodinuclear magnetic complexes has been studied. For the former, the accuracy is similar to other simple cases involving homodinuclear complexes, the main limitation being a sufficient inclusion of dynamical correlation effects. Nevertheless, these series of calculations provide an appropriate benchmark for density functional theory based methods. Here, the usual broken symmetry approach provides a convenient framework to predict the magnetic coupling constants but requires deriving the appropriate mapping. At variance with simple dinuclear complexes, spin projection based techniques cannot recover the corresponding (approximate) spin adapted solution. Present results also show that current implementation of spin flip techniques leads to unphysical results. PMID:26579753

  1. Approach for Structurally Clearing an Adaptive Compliant Trailing Edge Flap for Flight

    NASA Technical Reports Server (NTRS)

    Miller, Eric J.; Lokos, William A.; Cruz, Josue; Crampton, Glen; Stephens, Craig A.; Kota, Sridhar; Ervin, Gregory; Flick, Pete

    2015-01-01

    The Adaptive Compliant Trailing Edge (ACTE) flap was flown on the National Aeronautics and Space Administration (NASA) Gulfstream GIII testbed at the NASA Armstrong Flight Research Center. This smoothly curving flap replaced the existing Fowler flaps creating a seamless control surface. This compliant structure, developed by FlexSys Inc. in partnership with the Air Force Research Laboratory, supported NASA objectives for airframe structural noise reduction, aerodynamic efficiency, and wing weight reduction through gust load alleviation. A thorough structures airworthiness approach was developed to move this project safely to flight. A combination of industry and NASA standard practice require various structural analyses, ground testing, and health monitoring techniques for showing an airworthy structure. This paper provides an overview of compliant structures design, the structural ground testing leading up to flight, and the flight envelope expansion and monitoring strategy. Flight data will be presented, and lessons learned along the way will be highlighted.

  2. Building the framework for climate change adaptation in the urban areas using participatory approach: the Czech Republic experience

    NASA Astrophysics Data System (ADS)

    Emmer, Adam; Hubatová, Marie; Lupač, Miroslav; Pondělíček, Michael; Šafařík, Miroslav; Šilhánková, Vladimíra; Vačkář, David

    2016-04-01

    The Czech Republic has experienced numerous extreme hydrometeorological / climatological events such as floods (significant ones in 1997, 2002, 2010, 2013), droughts (2013, 2015), heat waves (2015) and windstorms (2007) during past decades. These events are generally attributed to the ongoing climate change and caused loss of lives and significant material damages (up to several % of GDP in some years), especially in urban areas. To initiate the adaptation process of urban areas, the main objective was to prepare a framework for creating climate change adaptation strategies of individual cities reflecting physical-geographical and socioeconomical conditions of the Czech Republic. Three pilot cities (Hradec Králové, Žďár nad Sázavou, Dobru\\vska) were used to optimize entire procedure. Two sets of participatory seminars were organised in order to involve all key stakeholders (the city council, department of the environment, department of the crisis management, hydrometeorological institute, local experts, ...) into the process of creation of the adaptation strategy from its early stage. Lesson learned for the framework were related especially to its applicability on a local level, which is largely a matter of the understandability of the concept. Finally, this illustrative and widely applicable framework (so called 'road map to adaptation strategy') includes five steps: (i) analysis of existing strategies and plans on national, regional and local levels; (ii) analysing climate-change related hazards and key vulnerabilities; (iii) identification of adaptation needs, evaluation of existing adaptation capacity and formulation of future adaptation priorities; (iv) identification of limits and barriers for the adaptation (economical, environmental, ...); and (v) selection of specific types of adaptation measures reflecting identified adaptation needs and formulated adaptation priorities. Keywords: climate change adaptation (CCA); urban areas; participatory approach

  3. Lysine Residues Are Not Required for Proteasome-Mediated Proteolysis of the Auxin/Indole Acidic Acid Protein IAA1.

    PubMed

    Gilkerson, Jonathan; Kelley, Dior R; Tam, Raymond; Estelle, Mark; Callis, Judy

    2015-06-01

    Although many ubiquitin-proteasome substrates have been characterized in plants, very little is known about the corresponding ubiquitin attachment(s) underlying regulated proteolysis. Current dogma asserts that ubiquitin is typically covalently attached to a substrate through an isopeptide bond between the ubiquitin carboxy terminus and a substrate lysyl amino group. However, nonlysine (non-Lys) ubiquitin attachment has been observed in other eukaryotes, including the N terminus, cysteine, and serine/threonine modification. Here, we investigate site(s) of ubiquitin attachment on indole-3-acetic acid1 (IAA1), a short-lived Arabidopsis (Arabidopsis thaliana) Auxin/indole-3-acetic acid (Aux/IAA) family member. Most Aux/IAA proteins function as negative regulators of auxin responses and are targeted for degradation after ubiquitination by the ubiquitin ligase SCF(TIR1/AFB) (for S-Phase Kinase-Associated Protein1, Cullin, F-box [SCF] with Transport Inhibitor Response1 [TIR1]/Auxin Signaling F-box [AFB]) by an interaction directly facilitated by auxin. Surprisingly, using a Histidine-Hemaglutinin (HIS(6x)-HA(3x)) epitope-tagged version expressed in vivo, Lys-less IAA1 was ubiquitinated and rapidly degraded in vivo. Lys-substituted versions of IAA1 localized to the nucleus as Yellow Fluorescent Protein fusions and interacted with both TIR1 and IAA7 in yeast (Saccharomyces cerevisiae) two-hybrid experiments, indicating that these proteins were functional. Ubiquitination on both HIS(6x)-HA(3x)-IAA1 and Lys-less HIS(6x)-HA(3x)-IAA1 proteins was sensitive to sodium hydroxide treatment, indicative of ubiquitin oxyester formation on serine or threonine residues. Additionally, base-resistant forms of ubiquitinated IAA1 were observed for HIS(6x)-HA(3x)-IAA1, suggesting additional lysyl-linked ubiquitin on this protein. Characterization of other Aux/IAA proteins showed that they have diverse degradation rates, adding additional complexity to auxin signaling. Altogether, these data

  4. Lysine Residues Are Not Required for Proteasome-Mediated Proteolysis of the Auxin/Indole Acidic Acid Protein IAA1.

    PubMed

    Gilkerson, Jonathan; Kelley, Dior R; Tam, Raymond; Estelle, Mark; Callis, Judy

    2015-06-01

    Although many ubiquitin-proteasome substrates have been characterized in plants, very little is known about the corresponding ubiquitin attachment(s) underlying regulated proteolysis. Current dogma asserts that ubiquitin is typically covalently attached to a substrate through an isopeptide bond between the ubiquitin carboxy terminus and a substrate lysyl amino group. However, nonlysine (non-Lys) ubiquitin attachment has been observed in other eukaryotes, including the N terminus, cysteine, and serine/threonine modification. Here, we investigate site(s) of ubiquitin attachment on indole-3-acetic acid1 (IAA1), a short-lived Arabidopsis (Arabidopsis thaliana) Auxin/indole-3-acetic acid (Aux/IAA) family member. Most Aux/IAA proteins function as negative regulators of auxin responses and are targeted for degradation after ubiquitination by the ubiquitin ligase SCF(TIR1/AFB) (for S-Phase Kinase-Associated Protein1, Cullin, F-box [SCF] with Transport Inhibitor Response1 [TIR1]/Auxin Signaling F-box [AFB]) by an interaction directly facilitated by auxin. Surprisingly, using a Histidine-Hemaglutinin (HIS(6x)-HA(3x)) epitope-tagged version expressed in vivo, Lys-less IAA1 was ubiquitinated and rapidly degraded in vivo. Lys-substituted versions of IAA1 localized to the nucleus as Yellow Fluorescent Protein fusions and interacted with both TIR1 and IAA7 in yeast (Saccharomyces cerevisiae) two-hybrid experiments, indicating that these proteins were functional. Ubiquitination on both HIS(6x)-HA(3x)-IAA1 and Lys-less HIS(6x)-HA(3x)-IAA1 proteins was sensitive to sodium hydroxide treatment, indicative of ubiquitin oxyester formation on serine or threonine residues. Additionally, base-resistant forms of ubiquitinated IAA1 were observed for HIS(6x)-HA(3x)-IAA1, suggesting additional lysyl-linked ubiquitin on this protein. Characterization of other Aux/IAA proteins showed that they have diverse degradation rates, adding additional complexity to auxin signaling. Altogether, these data

  5. Adaptive fuzzy approach to modeling of operational space for autonomous mobile robots

    NASA Astrophysics Data System (ADS)

    Musilek, Petr; Gupta, Madan M.

    1998-10-01

    Robots operating in an unstructured environment need high level of modeling of their operational space in order to plan a suitable path from an initial position to a desired goal. From this perspective, operational space modeling seems to be crucial to ensure a sufficient level of autonomy. In order to compile the information from various sources, we propose a fuzzy approach to evaluate each unit region on a grid map by a certain value of transition cost. This value expresses the cost of movement over the unit region: the higher the value, the more expensive the movement through the region in terms of energy, time, danger, etc. The approach for modeling, proposed in this paper, employs fuzzy granulation of information on various terrain features and their combination based on a fuzzy neural network. In order to adapt to the changing environmental conditions, and to improve the validity of constructed cost maps on-line, the system can be endowed with learning abilities. The learning subsystem would change parameters of the fuzzy neural network based decision system by reinforcements derived from comparisons of the actual cost of transition with the cost obtained from the model.

  6. An adaptive remaining energy prediction approach for lithium-ion batteries in electric vehicles

    NASA Astrophysics Data System (ADS)

    Wang, Yujie; Zhang, Chenbin; Chen, Zonghai

    2016-02-01

    With the growing number of electric vehicle (EV) applications, the function of the battery management system (BMS) becomes more sophisticated. The accuracy of remaining energy estimation is critical for energy optimization and management in EVs. Therefore the state-of-energy (SoE) is defined to indicate the remaining available energy of the batteries. Considering that there are inevitable accumulated errors caused by current and voltage integral method, an adaptive SoE estimator is first established in this paper. In order to establish a reasonable battery equivalent model, based on the experimental data of the LiFePO4 battery, a data-driven model is established to describe the relationship between the open-circuit voltage (OCV) and the SoE. What is more, the forgetting factor recursive least-square (RLS) method is used for parameter identification to get accurate model parameters. Finally, in order to analyze the robustness and the accuracy of the proposed approach, different types of dynamic current profiles are conducted on the lithium-ion batteries and the performances are calculated and compared. The results indicate that the proposed approach has robust and accurate SoE estimation results under dynamic working conditions.

  7. An error function minimization approach for the inverse problem of adaptive mirrors tuning

    NASA Astrophysics Data System (ADS)

    Vannoni, Maurizio; Yang, Fan; Siewert, Frank; Sinn, Harald

    2014-09-01

    Adaptive x-ray optics are more and more used in synchrotron beamlines, and it is probable that they will be considered for the future high-power free-electron laser sources, as the European XFEL now under construction in Hamburg, or similar projects now in discussion. These facilities will deliver a high power x-ray beam, with an expected high heat load delivered on the optics. For this reason, bendable mirrors are required to actively compensate the resulting wavefront distortion. On top of that, the mirror could have also intrinsic surface defects, as polishing errors or mounting stresses. In order to be able to correct the mirror surface with a high precision to maintain its challenging requirements, the mirror surface is usually characterized with a high accuracy metrology to calculate the actuators pulse functions and to assess its initial shape. After that, singular value decomposition (SVD) is used to find the signals to be applied into the actuators, to reach the desired surface deformation or correction. But in some cases this approach could be not robust enough for the needed performance. We present here a comparison between the classical SVD method and an error function minimization based on root-mean-square calculation. Some examples are provided, using a simulation of the European XFEL mirrors design as a case of study, and performances of the algorithms are evaluated in order to reach the ultimate quality in different scenarios. The approach could be easily generalized to other situations as well.

  8. An adaptive level set approach for incompressible two-phase flows

    SciTech Connect

    Sussman, M.; Almgren, A.S.; Bell, J.B.

    1997-04-01

    In Sussman, Smereka and Osher, a numerical method using the level set approach was formulated for solving incompressible two-phase flow with surface tension. In the level set approach, the interface is represented as the zero level set of a smooth function; this has the effect of replacing the advection of density, which has steep gradients at the interface, with the advection of the level set function, which is smooth. In addition, the interface can merge or break up with no special treatment. The authors maintain the level set function as the signed distance from the interface in order to robustly compute flows with high density ratios and stiff surface tension effects. In this work, they couple the level set scheme to an adaptive projection method for the incompressible Navier-Stokes equations, in order to achieve higher resolution of the interface with a minimum of additional expense. They present two-dimensional axisymmetric and fully three-dimensional results of air bubble and water drop computations.

  9. A combined bottom-up and top-down approach for assessment of climate change adaptation options

    NASA Astrophysics Data System (ADS)

    Bhave, Ajay Gajanan; Mishra, Ashok; Raghuwanshi, Narendra Singh

    2014-10-01

    Focus of recent scientific research in the water sector has shifted from analysis of climate change impacts to assessment of climate change adaptation options. However, limited attention has been given to integration of bottom-up and top-down methods for assessment of adaptation options. The integrated approach used in this study uses hydrological modelling to assess the effect of stakeholder prioritized adaptation options for the Kangsabati river catchment in India. A series of 14 multi-level stakeholder consultations are used to ascertain locally relevant no-regret adaptation options using Multi-Criteria Analysis (MCA) and scenario analysis methods. A validated Water Evaluation And Planning (WEAP) model is then used to project the effect of three options; option 1 check dams (CD), option 2 increasing forest cover (IFC) and option 3 combined CD and IFC, on future (2021-2050) streamflow. High resolution (˜25 km) climatic projections from four Regional Climate Models (RCMs) and their ensemble based on the SRES A1B scenario for the mid-21st century period are used to force the WEAP model. Results indicate that although all three adaptation options reduce streamflow, in comparison with scenario without adaptation, their magnitude, temporal pattern and effect on high and low streamflows are different. Options 2 and 3 reduce streamflow percentage by an order of magnitude greater than option 1. These characteristics affect their ability to address key adaptation requirements and therefore, we find that IFC emerges as a hydrologically suitable adaptation option for the study area. Based on study results we also conclude that such an integrated approach is advantageous and is a valuable tool for locally relevant climate change adaptation policymaking.

  10. Genome-wide survey of Aux/IAA gene family members in potato (Solanum tuberosum): Identification, expression analysis, and evaluation of their roles in tuber development.

    PubMed

    Gao, Junpeng; Cao, Xiaoli; Shi, Shandang; Ma, Yuling; Wang, Kai; Liu, Shengjie; Chen, Dan; Chen, Qin; Ma, Haoli

    2016-03-01

    The Auxin/indole-3-acetic acid (Aux/IAA) genes encode short-lived nuclear proteins that are known to be involved in the primary cellular responses to auxin. To date, systematic analysis of the Aux/IAA genes in potato (Solanum tuberosum) has not been conducted. In this study, a total of 26 potato Aux/IAA genes were identified (designated from StIAA1 to StIAA26), and the distribution of four conserved domains shared by the StIAAs were analyzed based on multiple sequence alignment and a motif-based sequence analysis. A phylogenetic analysis of the Aux/IAA gene families of potato and Arabidopsis was also conducted. In order to assess the roles of StIAA genes in tuber development, the results of RNA-seq studies were reformatted to analyze the expression patterns of StIAA genes, and then verified by quantitative real-time PCR. A large number of StIAA genes (12 genes) were highly expressed in stolon organs and in during the tuber initiation and expansion developmental stages, and most of these genes were responsive to indoleacetic acid treatment. Our results suggested that StIAA genes were involved in the process of tuber development and provided insights into functional roles of potato Aux/IAA genes.

  11. Adapting Rational Unified Process (RUP) approach in designing a secure e-Tendering model

    NASA Astrophysics Data System (ADS)

    Mohd, Haslina; Robie, Muhammad Afdhal Muhammad; Baharom, Fauziah; Darus, Norida Muhd; Saip, Mohamed Ali; Yasin, Azman

    2016-08-01

    e-Tendering is an electronic processing of the tender document via internet and allow tenderer to publish, communicate, access, receive and submit all tender related information and documentation via internet. This study aims to design the e-Tendering system using Rational Unified Process approach. RUP provides a disciplined approach on how to assign tasks and responsibilities within the software development process. RUP has four phases that can assist researchers to adjust the requirements of various projects with different scope, problem and the size of projects. RUP is characterized as a use case driven, architecture centered, iterative and incremental process model. However the scope of this study only focusing on Inception and Elaboration phases as step to develop the model and perform only three of nine workflows (business modeling, requirements, analysis and design). RUP has a strong focus on documents and the activities in the inception and elaboration phases mainly concern the creation of diagrams and writing of textual descriptions. The UML notation and the software program, Star UML are used to support the design of e-Tendering. The e-Tendering design based on the RUP approach can contribute to e-Tendering developers and researchers in e-Tendering domain. In addition, this study also shows that the RUP is one of the best system development methodology that can be used as one of the research methodology in Software Engineering domain related to secured design of any observed application. This methodology has been tested in various studies in certain domains, such as in Simulation-based Decision Support, Security Requirement Engineering, Business Modeling and Secure System Requirement, and so forth. As a conclusion, these studies showed that the RUP one of a good research methodology that can be adapted in any Software Engineering (SE) research domain that required a few artifacts to be generated such as use case modeling, misuse case modeling, activity

  12. A Surrogate-based Adaptive Sampling Approach for History Matching and Uncertainty Quantification

    SciTech Connect

    Li, Weixuan; Zhang, Dongxiao; Lin, Guang

    2015-02-25

    A critical procedure in reservoir simulations is history matching (or data assimilation in a broader sense), which calibrates model parameters such that the simulation results are consistent with field measurements, and hence improves the credibility of the predictions given by the simulations. Often there exist non-unique combinations of parameter values that all yield the simulation results matching the measurements. For such ill-posed history matching problems, Bayesian theorem provides a theoretical foundation to represent different solutions and to quantify the uncertainty with the posterior PDF. Lacking an analytical solution in most situations, the posterior PDF may be characterized with a sample of realizations, each representing a possible scenario. A novel sampling algorithm is presented here for the Bayesian solutions to history matching problems. We aim to deal with two commonly encountered issues: 1) as a result of the nonlinear input-output relationship in a reservoir model, the posterior distribution could be in a complex form, such as multimodal, which violates the Gaussian assumption required by most of the commonly used data assimilation approaches; 2) a typical sampling method requires intensive model evaluations and hence may cause unaffordable computational cost. In the developed algorithm, we use a Gaussian mixture model as the proposal distribution in the sampling process, which is simple but also flexible to approximate non-Gaussian distributions and is particularly efficient when the posterior is multimodal. Also, a Gaussian process is utilized as a surrogate model to speed up the sampling process. Furthermore, an iterative scheme of adaptive surrogate refinement and re-sampling ensures sampling accuracy while keeping the computational cost at a minimum level. The developed approach is demonstrated with an illustrative example and shows its capability in handling the above-mentioned issues. Multimodal posterior of the history matching

  13. The Fate of Early Experience Following Developmental Change: Longitudinal Approaches to Individual Adaptation in Childhood.

    ERIC Educational Resources Information Center

    Sroufe, L. Alan; And Others

    1990-01-01

    Examined Bowlby's proposition that early experiences and the adaptations to which they give rise influence later development, even beyond the influence of current circumstances or very recent adaptation. Groups whose adaptation were similar during preschool years but consistently different earlier were defined and compared. Results supported…

  14. An Adaptive Management Approach for Summer Water Level Reductions on the Upper Mississippi River System

    USGS Publications Warehouse

    Johnson, B.L.; Barko, J.W.; Clevenstine, R.; Davis, M.; Galat, D.L.; Lubinski, S.J.; Nestler, J.M.

    2010-01-01

    The primary purpose of this report is to provide an adaptive management approach for learning more about summer water level reductions (drawdowns) as a management tool, including where and how drawdowns can be applied most effectively within the Upper Mississippi River System. The report reviews previous drawdowns conducted within the system and provides specific recommendations for learning more about the lesser known effects of drawdowns and how the outcomes can be influenced by different implementation strategies and local conditions. The knowledge gained can be used by managers to determine how best to implement drawdowns in different parts of the UMRS to help achieve management goals. The information and recommendations contained in the report are derived from results of previous drawdown projects, insights from regional disciplinary experts, and the experience of the authors in experimental design, modeling, and monitoring. Modeling is a critical part of adaptive management and can involve conceptual models, simulation models, and empirical models. In this report we present conceptual models that express current understanding regarding functioning of the UMRS as related to drawdowns and highlight interactions among key ecological components of the system. The models were developed within the constraints of drawdown timing, magnitude (depth), and spatial differences in effects (longitudinal and lateral) with attention to ecological processes affected by drawdowns. With input from regional experts we focused on the responses of vegetation, fish, mussels, other invertebrates, and birds. The conceptual models reflect current understanding about relations and interactions among system components, the expected strength of those interactions, potential responses of system components to drawdowns, likelihood of the response occurring, and key uncertainties that limit our ability to make accurate predictions of effects (Table 1, Fig. 4-10). Based on this current

  15. An integrated stochastic approach to the assessment of agricultural water demand and adaptation to water scarcity

    NASA Astrophysics Data System (ADS)

    Foster, T.; Butler, A. P.; McIntyre, N.

    2012-12-01

    Increasing water demands from growing populations coupled with changing water availability, for example due to climate change, are likely to increase water scarcity. Agriculture will be exposed to risk due to the importance of reliable water supplies as an input to crop production. To assess the efficiency of agricultural adaptation options requires a sound understanding of the relationship between crop growth and water application. However, most water resource planning models quantify agricultural water demand using highly simplified, temporally lumped estimated crop-water production functions (CWPFs). Such CWPFs fail to capture the biophysical complexities in crop-water relations and mischaracterise farmers ability to respond to water scarcity. Application of these models in policy analyses will be ineffective and may lead to unsustainable water policies. Crop simulation models provide an alternative means of defining the complex nature of the CWPF. Here we develop a daily water-limited crop model for this purpose. The model is based on the approach used in the FAO's AquaCrop model, balancing biophysical and computational complexities. We further develop the model by incorporating improved simulation routines to calculate the distribution of water through the soil profile. Consequently we obtain a more realistic representation of the soil water balance with concurrent improvements in the prediction of water-limited yield. We introduce a methodology to utilise this model for the generation of stochastic crop-water production functions (SCWPFs). This is achieved by running the model iteratively with both time series of climatic data and variable quantities of irrigation water, employing a realistic rule-based approach to farm irrigation scheduling. This methodology improves the representation of potential crop yields, capturing both the variable effects of water deficits on crop yield and the stochastic nature of the CWPF due to climatic variability. Application to

  16. Stability evaluation and improvement of adaptive optics systems by using the Lyapunov stability approach

    NASA Astrophysics Data System (ADS)

    Wang, Liang; Chen, Tao; Liu, Xin-yue; Lin, Xu-dong; Yang, Xiao-xia; Li, Hong-zhuang

    2016-02-01

    In this research, investigations on the closed-loop control stability of adaptive optics systems are conducted by using the Lyapunov approach. As an direct metric of the control stability, the error propagator includes the effects of both the integral gain and the influence matrix and is effective for control-stability evaluation. An experimental 97-element AO system is developed for the control-stability investigation, and the Southwell sensor-actuator configuration rather than the Fried geometry is adopted so as to suppress the potential waffle mode. Because filtering out small singular values of the influence matrix can be used to improve the control stability, the effect of the influence matrix and the effect of the integral gain are considered as a whole by using the error propagator. Then, the control stability of the AO system is evaluated for varying the integral gains and the number of filtered-out singular values. Afterwards, an analysis of the evaluations of the error propagator is made, and a conclusion can be drawn that the control stability can be improved by filtering out more singular values of the influence matrix when the integral gain is high. In other words, the error propagator is useful for trading off the bandwidth error and the fitting error of AO systems in a control-stability approach. Finally, a performance measurement of the experimental AO system is conducted when 13 smaller singular values of the influence matrix are filtered out, and the results show that filtering out a small fraction of the singular values has a minor influence on the performance of this AO system.

  17. The role of idiotypic interactions in the adaptive immune system: a belief-propagation approach

    NASA Astrophysics Data System (ADS)

    Bartolucci, Silvia; Mozeika, Alexander; Annibale, Alessia

    2016-08-01

    In this work we use belief-propagation techniques to study the equilibrium behaviour of a minimal model for the immune system comprising interacting T and B clones. We investigate the effect of the so-called idiotypic interactions among complementary B clones on the system’s activation. Our results show that B-B interactions increase the system’s resilience to noise, making clonal activation more stable, while increasing the cross-talk between different clones. We derive analytically the noise level at which a B clone gets activated, in the absence of cross-talk, and find that this increases with the strength of idiotypic interactions and with the number of T cells sending signals to the B clones. We also derive, analytically and numerically, via population dynamics, the critical line where clonal cross-talk arises. Our approach allows us to derive the B clone size distribution, which can be experimentally measured and gives important information about the adaptive immune system response to antigens and vaccination.

  18. The role of idiotypic interactions in the adaptive immune system: a belief-propagation approach

    NASA Astrophysics Data System (ADS)

    Bartolucci, Silvia; Mozeika, Alexander; Annibale, Alessia

    2016-08-01

    In this work we use belief-propagation techniques to study the equilibrium behaviour of a minimal model for the immune system comprising interacting T and B clones. We investigate the effect of the so-called idiotypic interactions among complementary B clones on the system’s activation. Our results show that B–B interactions increase the system’s resilience to noise, making clonal activation more stable, while increasing the cross-talk between different clones. We derive analytically the noise level at which a B clone gets activated, in the absence of cross-talk, and find that this increases with the strength of idiotypic interactions and with the number of T cells sending signals to the B clones. We also derive, analytically and numerically, via population dynamics, the critical line where clonal cross-talk arises. Our approach allows us to derive the B clone size distribution, which can be experimentally measured and gives important information about the adaptive immune system response to antigens and vaccination.

  19. A New Controller for PMSM Servo Drive Based on the Sliding Mode Approach with Parameter Adaptation

    NASA Astrophysics Data System (ADS)

    Gjini, Orges; Kaneko, Takayuki; Ohsawa, Hiroshi

    A novel controller based on the Sliding Mode (SM) approach is designed for controlling a permanent magnet synchronous motor (PMSM) in a servo drive. After analyzing the classical SM controller, changes are made in the controller design such that its performance is substantially improved. To improve the controller performance in steady state (zero error positioning) an integral block is added to the controller resulting in a new controller configuration, which we call Sliding Mode Integral (SMI) controller. The new controller is tuned based on the results from parameter identification of the motor and the working machine. To cope with model parameter variations, especially unpredictable friction changes, gain scheduling and fuzzy based adaptive techniques are used in the control algorithm. Experiments and simulations are carried out and their results show a high performance control. The new controller offers very good tracking; it is highly robust, reaches the final position very fast and has a large stall torque. Furthermore the application of the SM ensures reduction of the system order by one. For comparison, the new controller's performance is compared with that of a PI controller. From the experimental results it is obvious the superiority of the new proposed controller.

  20. Trickle-down evolution: an approach to getting major evolutionary adaptive changes into textbooks and curricula.

    PubMed

    Padian, Kevin

    2008-08-01

    Although contemporary high school and college textbooks of biology generally cover the principles and data of microevolution (genetic and populational change) and speciation rather well, coverage of what is known of the major changes in evolution (macroevolution), and how the evidence is understood is generally poor to nonexistent. It is critical to improve this because acceptance of evolution by the American public rests on the understanding of how we know what we know about the emergence of major new taxonomic groups, and about their adaptations, behaviors, and ecologies in geologic time. An efficient approach to this problem is to improve the illustrations in college textbooks to show the consilience of different lines of fossil, morphological, and molecular evidence mapped on phylogenies. Such "evograms" will markedly improve traditional illustrations of phylogenies, "menageries," and "companatomies." If "evograms" are installed at the college level, the basic principles and evidence of macroevolution will be more likely taught in K-12, thus providing an essential missing piece in biological education. PMID:21669782

  1. Estimating oxygen consumption from heart rate using adaptive neuro-fuzzy inference system and analytical approaches.

    PubMed

    Kolus, Ahmet; Dubé, Philippe-Antoine; Imbeau, Daniel; Labib, Richard; Dubeau, Denise

    2014-11-01

    In new approaches based on adaptive neuro-fuzzy systems (ANFIS) and analytical method, heart rate (HR) measurements were used to estimate oxygen consumption (VO2). Thirty-five participants performed Meyer and Flenghi's step-test (eight of which performed regeneration release work), during which heart rate and oxygen consumption were measured. Two individualized models and a General ANFIS model that does not require individual calibration were developed. Results indicated the superior precision achieved with individualized ANFIS modelling (RMSE = 1.0 and 2.8 ml/kg min in laboratory and field, respectively). The analytical model outperformed the traditional linear calibration and Flex-HR methods with field data. The General ANFIS model's estimates of VO2 were not significantly different from actual field VO2 measurements (RMSE = 3.5 ml/kg min). With its ease of use and low implementation cost, the General ANFIS model shows potential to replace any of the traditional individualized methods for VO2 estimation from HR data collected in the field. PMID:24793823

  2. An Adaptive Approach to Family Intervention: Linking Engagement in Family-Centered Intervention to Reductions in Adolescent Problem Behavior

    ERIC Educational Resources Information Center

    Connell, Arin M.; Dishion, Thomas J.; Yasui, Miwa; Kavanagh, Kathryn

    2007-01-01

    This study used Complier Average Causal Effect analysis (CACE; see G. Imbens & D. Rubin, 1997) to examine the impact of an adaptive approach to family intervention in the public schools on rates of substance use and antisocial behavior among students ages 11-17. Students were randomly assigned to a family-centered intervention (N = 998) in 6th…

  3. Genetics of Aux/IAA and ARF action in plant growth and development.

    PubMed

    Liscum, E; Reed, J W

    2002-01-01

    Dramatic advances in our understanding of auxin signal-response pathways have been made in recent years. Much of this new knowledge has come through the study of mutants in Arabidopsis thaliana. Mutations have been identified in a wide variety of auxin-response components, including auxin transporters, protein kinases and phosphatases, components of a ubiquitin-proteosome pathway, and transcriptional regulators. This review focuses on mutations that affect auxin-modulated transcription factors, in particular those in the Aux/IAA and AUXIN RESPONSE FACTOR (ARF) genes. Mutants in members of these related gene families exhibit phenotypes that indicate both unique localized functions, as well as overlapping redundant functions, throughout plant development - from embryogenesis to flowering. Effects of specific mutations on Aux/IAA and ARF protein functions at the biochemical and physiological levels will be discussed. We will also discuss potential mechanisms for interactions between auxin and light response pathways that are suggested by these mutants.

  4. Studies on the longitudinal and lateral transport of IAA in the shoots of etiolated corn seedlings

    NASA Technical Reports Server (NTRS)

    Epel, B. L.; Warmbrodt, R. P.; Bandurski, R. S.

    1992-01-01

    The auxin, indole-3-acetic acid, and the symplastic probe, carboxyfluorescein diacetate, were applied to the cut mesocotyl base or coleoptile apex of etiolated Zea mays seedlings and their transport measured and tissue distribution determined. The longitudinal transport of indole-3-acetate was strongly basipolar, while that of carboxyfluorescein was essentially apolar. The longitudinal transport of IAA, like carboxyfluorescein, was mainly in the stele. IAA exhibited a much higher lateral mobility from stele to cortex than did carboxyfluorescein. Based on the calculation of moles probe/kg fw, IAA is 4 times more concentrated in the stele than in the cortex while CF is 24 times higher in concentration in the stele than in the cortex. The structure of the node and the mesocotyl regions just below the node, regions of maximum growth, were examined and plasmodesmatal structure and frequency in these regions determined. The plasmodesmatal frequency, about 3 per micrometer2, between all cell types of the mesocotyl was found to be about 5-8 fold higher than that found for the root. Hypotheses of lateral auxin transport are discussed.

  5. Influence of zygomycete-derived D'orenone on IAA signalling in Tricholoma-spruce ectomycorrhiza.

    PubMed

    Wagner, Katharina; Krause, Katrin; David, Anja; Kai, Marco; Jung, Elke-Martina; Sammer, Dominik; Kniemeyer, Olaf; Boland, Wilhelm; Kothe, Erika

    2016-09-01

    Despite the rising interest in microbial communication, only few studies relate to mycorrhization and the pool of potential morphogenic substances produced by the surrounding soil community. Here, we investigated the effect exerted by the C18 - ketone β-apo-13-carotenone, D'orenone, on the ectomycorrhizal basidiomycete Tricholoma vaccinum and its symbiosis with the economically important host tree, spruce (Picea abies). D'orenone is an early intermediate in the biosynthesis of morphogens in sexual development of mucoromycetes, the trisporoids. In the ectomycorrhizal fungus T. vaccinum, D'orenone increased the production and/or release of the phytohormone indole-3-acetic acid (IAA) which had been proposed to be involved in the mutual symbiosis. The induced expression of the fungal aldehyde dehydrogenase, Ald5 is associated with IAA synthesis and excretion. In the host tree, D'orenone modulated root architecture by increasing lateral root length and hypertrophy of root cortex cells, likely via changed IAA concentrations and flux. Thus, we report for the first time on carotenoid metabolites from soil fungi affecting both ectomycorrhizal partners. The data imply a complex network of functions for secondary metabolites which act in an inter-kingdom signalling in soil. PMID:26636983

  6. Adaptive patch-based POCS approach for super resolution reconstruction of 4D-CT lung data.

    PubMed

    Wang, Tingting; Cao, Lei; Yang, Wei; Feng, Qianjin; Chen, Wufan; Zhang, Yu

    2015-08-01

    Image enhancement of lung four-dimensional computed tomography (4D-CT) data is highly important because image resolution remains a crucial point in lung cancer radiotherapy. In this paper, we proposed a method for lung 4D-CT super resolution (SR) by using an adaptive-patch-based projection onto convex sets (POCS) approach, which is in contrast with the global POCS SR algorithm, to recover fine details with lesser artifacts in images. The main contribution of this patch-based approach is that the interfering local structure from other phases can be rejected by employing a similar patch adaptive selection strategy. The effectiveness of our approach is demonstrated through experiments on simulated images and real lung 4D-CT datasets. A comparison with previously published SR reconstruction methods highlights the favorable characteristics of the proposed method.

  7. Adaptive patch-based POCS approach for super resolution reconstruction of 4D-CT lung data

    NASA Astrophysics Data System (ADS)

    Wang, Tingting; Cao, Lei; Yang, Wei; Feng, Qianjin; Chen, Wufan; Zhang, Yu

    2015-08-01

    Image enhancement of lung four-dimensional computed tomography (4D-CT) data is highly important because image resolution remains a crucial point in lung cancer radiotherapy. In this paper, we proposed a method for lung 4D-CT super resolution (SR) by using an adaptive-patch-based projection onto convex sets (POCS) approach, which is in contrast with the global POCS SR algorithm, to recover fine details with lesser artifacts in images. The main contribution of this patch-based approach is that the interfering local structure from other phases can be rejected by employing a similar patch adaptive selection strategy. The effectiveness of our approach is demonstrated through experiments on simulated images and real lung 4D-CT datasets. A comparison with previously published SR reconstruction methods highlights the favorable characteristics of the proposed method.

  8. Student Approaches to Learning in Physics--Validity and Exploration Using Adapted SPQ

    ERIC Educational Resources Information Center

    Sharma, Manjula Devi; Stewart, Chris; Wilson, Rachel; Gokalp, Muhammed Sait

    2013-01-01

    The aim of this study was to investigate an adaptation of the Study Processes Questionnaire for the discipline of physics. A total of 2030 first year physics students at an Australian metropolitan university completed the questionnaire over three different year cohorts. The resultant data has been used to explore whether the adaptation of the…

  9. An object-oriented approach for parallel self adaptive mesh refinement on block structured grids

    NASA Technical Reports Server (NTRS)

    Lemke, Max; Witsch, Kristian; Quinlan, Daniel

    1993-01-01

    Self-adaptive mesh refinement dynamically matches the computational demands of a solver for partial differential equations to the activity in the application's domain. In this paper we present two C++ class libraries, P++ and AMR++, which significantly simplify the development of sophisticated adaptive mesh refinement codes on (massively) parallel distributed memory architectures. The development is based on our previous research in this area. The C++ class libraries provide abstractions to separate the issues of developing parallel adaptive mesh refinement applications into those of parallelism, abstracted by P++, and adaptive mesh refinement, abstracted by AMR++. P++ is a parallel array class library to permit efficient development of architecture independent codes for structured grid applications, and AMR++ provides support for self-adaptive mesh refinement on block-structured grids of rectangular non-overlapping blocks. Using these libraries, the application programmers' work is greatly simplified to primarily specifying the serial single grid application and obtaining the parallel and self-adaptive mesh refinement code with minimal effort. Initial results for simple singular perturbation problems solved by self-adaptive multilevel techniques (FAC, AFAC), being implemented on the basis of prototypes of the P++/AMR++ environment, are presented. Singular perturbation problems frequently arise in large applications, e.g. in the area of computational fluid dynamics. They usually have solutions with layers which require adaptive mesh refinement and fast basic solvers in order to be resolved efficiently.

  10. Development and Climate Change: A Mainstreaming Approach for Assessing Economic, Social, and Environmental Impacts of Adaptation Measures

    NASA Astrophysics Data System (ADS)

    Halsnæs, Kirsten; Trærup, Sara

    2009-05-01

    The paper introduces the so-called climate change mainstreaming approach, where vulnerability and adaptation measures are assessed in the context of general development policy objectives. The approach is based on the application of a limited set of indicators. These indicators are selected as representatives of focal development policy objectives, and a stepwise approach for addressing climate change impacts, development linkages, and the economic, social and environmental dimensions related to vulnerability and adaptation are introduced. Within this context it is illustrated using three case studies how development policy indicators in practice can be used to assess climate change impacts and adaptation measures based on three case studies, namely a road project in flood prone areas of Mozambique, rainwater harvesting in the agricultural sector in Tanzania and malaria protection in Tanzania. The conclusions of the paper confirm that climate risks can be reduced at relatively low costs, but the uncertainty is still remaining about some of the wider development impacts of implementing climate change adaptation measures.

  11. Development and climate change: a mainstreaming approach for assessing economic, social, and environmental impacts of adaptation measures.

    PubMed

    Halsnaes, Kirsten; Traerup, Sara

    2009-05-01

    The paper introduces the so-called climate change mainstreaming approach, where vulnerability and adaptation measures are assessed in the context of general development policy objectives. The approach is based on the application of a limited set of indicators. These indicators are selected as representatives of focal development policy objectives, and a stepwise approach for addressing climate change impacts, development linkages, and the economic, social and environmental dimensions related to vulnerability and adaptation are introduced. Within this context it is illustrated using three case studies how development policy indicators in practice can be used to assess climate change impacts and adaptation measures based on three case studies, namely a road project in flood prone areas of Mozambique, rainwater harvesting in the agricultural sector in Tanzania and malaria protection in Tanzania. The conclusions of the paper confirm that climate risks can be reduced at relatively low costs, but the uncertainty is still remaining about some of the wider development impacts of implementing climate change adaptation measures.

  12. Genome-wide survey and comprehensive expression profiling of Aux/IAA gene family in chickpea and soybean

    PubMed Central

    Singh, Vikash K.; Jain, Mukesh

    2015-01-01

    Auxin plays a central role in many aspects of plant growth and development. Auxin/Indole-3-Acetic Acid (Aux/IAA) genes cooperate with several other components in the perception and signaling of plant hormone auxin. An investigation of chickpea and soybean genomes revealed 22 and 63 putative Aux/IAA genes, respectively. These genes were classified into six subfamilies on the basis of phylogenetic analysis. Among 63 soybean Aux/IAA genes, 57 (90.5%) were found to be duplicated via whole genome duplication (WGD)/segmental events. Transposed duplication played a significant role in tandem arrangements between the members of different subfamilies. Analysis of Ka/Ks ratio of duplicated Aux/IAA genes revealed purifying selection pressure with restricted functional divergence. Promoter sequence analysis revealed several cis-regulatory elements related to auxin, abscisic acid, desiccation, salt, seed, and endosperm, indicating their role in development and stress responses. Expression analysis of chickpea and soybean Aux/IAA genes in various tissues and stages of development demonstrated tissue/stage specific differential expression. In soybean, at least 16 paralog pairs, duplicated via WGD/segmental events, showed almost indistinguishable expression pattern, but eight pairs exhibited significantly diverse expression patterns. Under abiotic stress conditions, such as desiccation, salinity and/or cold, many Aux/IAA genes of chickpea and soybean revealed differential expression. qRT-PCR analysis confirmed the differential expression patterns of selected Aux/IAA genes in chickpea. The analyses presented here provide insights on putative roles of chickpea and soybean Aux/IAA genes and will facilitate elucidation of their precise functions during development and abiotic stress responses. PMID:26579165

  13. Increased levels of IAA are required for system 2 ethylene synthesis causing fruit softening in peach (Prunus persica L. Batsch).

    PubMed

    Tatsuki, Miho; Nakajima, Naoko; Fujii, Hiroshi; Shimada, Takehiko; Nakano, Michiharu; Hayashi, Ken-ichiro; Hayama, Hiroko; Yoshioka, Hirohito; Nakamura, Yuri

    2013-02-01

    The fruit of melting-flesh peach (Prunus persica L. Batsch) cultivars produce high levels of ethylene caused by high expression of PpACS1 (an isogene of 1-aminocyclopropane-1-carboxylic acid synthase), resulting in rapid fruit softening at the late-ripening stage. In contrast, the fruit of stony hard peach cultivars do not soften and produce little ethylene due to low expression of PpACS1. To elucidate the mechanism for suppressing PpACS1 expression in stony hard peaches, a microarray analysis was performed. Several genes that displayed similar expression patterns as PpACS1 were identified and shown to be indole-3-acetic acid (IAA)-inducible genes (Aux/IAA, SAUR). That is, expression of IAA-inducible genes increased at the late-ripening stage in melting flesh peaches; however, these transcripts were low in mature fruit of stony hard peaches. The IAA concentration increased suddenly just before harvest time in melting flesh peaches exactly coinciding with system 2 ethylene production. In contrast, the IAA concentration did not increase in stony hard peaches. Application of 1-naphthalene acetic acid, a synthetic auxin, to stony hard peaches induced a high level of PpACS1 expression, a large amount of ethylene production and softening. Application of an anti-auxin, α-(phenylethyl-2-one)-IAA, to melting flesh peaches reduced levels of PpACS1 expression and ethylene production. These observations indicate that suppression of PpACS1 expression at the late-ripening stage of stony hard peach may result from a low level of IAA and that a high concentration of IAA is required to generate a large amount of system 2 ethylene in peaches.

  14. Development of a new adaptive ordinal approach to continuous-variable probabilistic optimization.

    SciTech Connect

    Romero, Vicente JosÔe; Chen, Chun-Hung (George Mason University, Fairfax, VA)

    2006-11-01

    A very general and robust approach to solving continuous-variable optimization problems involving uncertainty in the objective function is through the use of ordinal optimization. At each step in the optimization problem, improvement is based only on a relative ranking of the uncertainty effects on local design alternatives, rather than on precise quantification of the effects. One simply asks ''Is that alternative better or worse than this one?'' -not ''HOW MUCH better or worse is that alternative to this one?'' The answer to the latter question requires precise characterization of the uncertainty--with the corresponding sampling/integration expense for precise resolution. However, in this report we demonstrate correct decision-making in a continuous-variable probabilistic optimization problem despite extreme vagueness in the statistical characterization of the design options. We present a new adaptive ordinal method for probabilistic optimization in which the trade-off between computational expense and vagueness in the uncertainty characterization can be conveniently managed in various phases of the optimization problem to make cost-effective stepping decisions in the design space. Spatial correlation of uncertainty in the continuous-variable design space is exploited to dramatically increase method efficiency. Under many circumstances the method appears to have favorable robustness and cost-scaling properties relative to other probabilistic optimization methods, and uniquely has mechanisms for quantifying and controlling error likelihood in design-space stepping decisions. The method is asymptotically convergent to the true probabilistic optimum, so could be useful as a reference standard against which the efficiency and robustness of other methods can be compared--analogous to the role that Monte Carlo simulation plays in uncertainty propagation.

  15. A neural learning approach for adaptive image restoration using a fuzzy model-based network architecture.

    PubMed

    Wong, H S; Guan, L

    2001-01-01

    We address the problem of adaptive regularization in image restoration by adopting a neural-network learning approach. Instead of explicitly specifying the local regularization parameter values, they are regarded as network weights which are then modified through the supply of appropriate training examples. The desired response of the network is in the form of a gray level value estimate of the current pixel using weighted order statistic (WOS) filter. However, instead of replacing the previous value with this estimate, this is used to modify the network weights, or equivalently, the regularization parameters such that the restored gray level value produced by the network is closer to this desired response. In this way, the single WOS estimation scheme can allow appropriate parameter values to emerge under different noise conditions, rather than requiring their explicit selection in each occasion. In addition, we also consider the separate regularization of edges and textures due to their different noise masking capabilities. This in turn requires discriminating between these two feature types. Due to the inability of conventional local variance measures to distinguish these two high variance features, we propose the new edge-texture characterization (ETC) measure which performs this discrimination based on a scalar value only. This is then incorporated into a fuzzified form of the previous neural network which determines the degree of membership of each high variance pixel in two fuzzy sets, the EDGE and TEXTURE fuzzy sets, from the local ETC value, and then evaluates the appropriate regularization parameter by appropriately combining these two membership function values.

  16. a Local Adaptive Approach for Dense Stereo Matching in Architectural Scene Reconstruction

    NASA Astrophysics Data System (ADS)

    Stentoumis, C.; Grammatikopoulos, L.; Kalisperakis, I.; Petsa, E.; Karras, G.

    2013-02-01

    In recent years, a demand for 3D models of various scales and precisions has been growing for a wide range of applications; among them, cultural heritage recording is a particularly important and challenging field. We outline an automatic 3D reconstruction pipeline, mainly focusing on dense stereo-matching which relies on a hierarchical, local optimization scheme. Our matching framework consists of a combination of robust cost measures, extracted via an intuitive cost aggregation support area and set within a coarse-tofine strategy. The cost function is formulated by combining three individual costs: a cost computed on an extended census transformation of the images; the absolute difference cost, taking into account information from colour channels; and a cost based on the principal image derivatives. An efficient adaptive method of aggregating matching cost for each pixel is then applied, relying on linearly expanded cross skeleton support regions. Aggregated cost is smoothed via a 3D Gaussian function. Finally, a simple "winnertakes- all" approach extracts the disparity value with minimum cost. This keeps algorithmic complexity and system computational requirements acceptably low for high resolution images (or real-time applications), when compared to complex matching functions of global formulations. The stereo algorithm adopts a hierarchical scheme to accommodate high-resolution images and complex scenes. In a last step, a robust post-processing work-flow is applied to enhance the disparity map and, consequently, the geometric quality of the reconstructed scene. Successful results from our implementation, which combines pre-existing algorithms and novel considerations, are presented and evaluated on the Middlebury platform.

  17. Magnesium deficiency effects on IAA-1-/sup 14/C decarboxylation in Alaska and Little Marvel pea tissues

    SciTech Connect

    Henry, E.W.; Haduck, P.; Haduck, W.; Joyner, M.

    1987-04-01

    This investigation seeks to determine the effects of magnesium deficiency on light and dark exposed Alaska (normal) and Little Marvel (dwarf) pea tissue, with respect to IAA-1-/sup 14/C decarboxylation, in root, stem, and leaf tissues. There is both a higher rate of IAA-1-/sup 14/C decarboxylation and enhanced stem growth in Alaska, vs. Little Marvel pea tissue. The decarboxylation of IAA-1-/sup 14/C is highest in roots, slightly lower in leaves, followed by the proximal and distal designated stem tissues. With respect to light effects, the absence of light causes a decrease in IAA-1-/sup 14/C decarboxylation, the effect being most prominent in the leaves, with the least effect being exhibited in the root tissue. In summary, magnesium deficiency causes a decrease in IAA-1-/sup 14/C decarboxylation in both Alaska and Little Marvel pea tissues. It is suggested that the lack of available magnesium causes general physiological stress, with the plant attempting to redistribute any of the still available endogenous ion. The rate and pathway of IAA metabolism may vary significant between different types of cells in magnesium deficient tissues.

  18. Effect of surface and membrane potentials on IAA (indoleactic acid) uptake and binding by zucchini membrane vesicles

    SciTech Connect

    Clark, K.A.; Goldsmith, M.H.M.

    1986-08-01

    The polar transport of the endogenous hormone controlling extension growth of plant cells, indoleacetic acid (IAA), is thought to depend on transmembrane pH and electrical gradients resulting in part from the action of proton ATPases in the plasma membrane. Elements of this transport process are permeation of the membrane by the undissociated lipophilic indoleacetic acid (IAAH) from the acidic apoplast, followed by dissociation of the weak acid and accumulation of the IAA anion (IAA/sup -/) in the alkaline cytoplasm; a saturable symport of IAA/sup -/ with one or more protons; a carrier-mediated efflux of IAA/sup -/ down a considerable electrochemical gradient. The efflux is greater from the basal than the apical end of cells and is thought to be responsible for the overall polarity of the process. This step is also the site of action of napthylphthalamic acid (NPA) and herbicides that inhibit polar transport but stimulate net accumulation of auxin by tissues and cells. We are using membrane vesicles as a simplified system for studying the mechanisms involved in the transport and accumulation of auxin. In particular, we are interested in determining the involvement of the transmembrane pH (pH/sub o/ < pH/sub i/) and voltage gradients (K/sup +/ diffusion potential, (K/sup +/)/sub in/ > (K/sup +/)/sub out/) in IAA uptake. 19 refs., 6 figs.

  19. The auxin Sl-IAA17 transcriptional repressor controls fruit size via the regulation of endoreduplication-related cell expansion.

    PubMed

    Su, Liyan; Bassa, Carole; Audran, Corinne; Mila, Isabelle; Cheniclet, Catherine; Chevalier, Christian; Bouzayen, Mondher; Roustan, Jean-Paul; Chervin, Christian

    2014-11-01

    Auxin is known to regulate cell division and cell elongation, thus controlling plant growth and development. Part of the auxin signaling pathway depends on the fine-tuned degradation of the auxin/indole acetic acid (Aux/IAA) transcriptional repressors. Recent evidence indicates that Aux/IAA proteins play a role in fruit development in tomato (Solanum lycopersicum Mill.), a model species for fleshy fruit development. We report here on the functional characterization of Sl-IAA17 during tomato fruit development. Silencing of Sl-IAA17 by an RNA interference (RNAi) strategy resulted in the production of larger fruit than the wild type. Histological analyses of the fruit organ and tissues demonstrated that this phenotype was associated with a thicker pericarp, rather than larger locules and/or a larger number of seeds. Microscopic analysis demonstrated that the higher pericarp thickness in Sl-IAA17 RNAi fruits was not due to a larger number of cells, but to the increase in cell size. Finally, we observed that the cell expansion in the transgenic fruits is tightly coupled with higher ploidy levels than in the wild type, suggesting a stimulation of the endoreduplication process. In conclusion, this work provides new insights into the function of the Aux/IAA pathway in fleshy fruit development, especially fruit size and cell size determination in tomato.

  20. Integrating evolutionary and functional approaches to infer adaptation at specific loci.

    PubMed

    Storz, Jay F; Wheat, Christopher W

    2010-09-01

    Inferences about adaptation at specific loci are often exclusively based on the static analysis of DNA sequence variation. Ideally,population-genetic evidence for positive selection serves as a stepping-off point for experimental studies to elucidate the functional significance of the putatively adaptive variation. We argue that inferences about adaptation at specific loci are best achieved by integrating the indirect, retrospective insights provided by population-genetic analyses with the more direct, mechanistic insights provided by functional experiments. Integrative studies of adaptive genetic variation may sometimes be motivated by experimental insights into molecular function, which then provide the impetus to perform population genetic tests to evaluate whether the functional variation is of adaptive significance. In other cases, studies may be initiated by genome scans of DNA variation to identify candidate loci for recent adaptation. Results of such analyses can then motivate experimental efforts to test whether the identified candidate loci do in fact contribute to functional variation in some fitness-related phenotype. Functional studies can provide corroborative evidence for positive selection at particular loci, and can potentially reveal specific molecular mechanisms of adaptation.

  1. Systems and Methods for Parameter Dependent Riccati Equation Approaches to Adaptive Control

    NASA Technical Reports Server (NTRS)

    Kim, Kilsoo (Inventor); Yucelen, Tansel (Inventor); Calise, Anthony J. (Inventor)

    2015-01-01

    Systems and methods for adaptive control are disclosed. The systems and methods can control uncertain dynamic systems. The control system can comprise a controller that employs a parameter dependent Riccati equation. The controller can produce a response that causes the state of the system to remain bounded. The control system can control both minimum phase and non-minimum phase systems. The control system can augment an existing, non-adaptive control design without modifying the gains employed in that design. The control system can also avoid the use of high gains in both the observer design and the adaptive control law.

  2. New Approach for IIR Adaptive Lattice Filter Structure Using Simultaneous Perturbation Algorithm

    NASA Astrophysics Data System (ADS)

    Martinez, Jorge Ivan Medina; Nakano, Kazushi; Higuchi, Kohji

    Adaptive infinite impulse response (IIR), or recursive, filters are less attractive mainly because of the stability and the difficulties associated with their adaptive algorithms. Therefore, in this paper the adaptive IIR lattice filters are studied in order to devise algorithms that preserve the stability of the corresponding direct-form schemes. We analyze the local properties of stationary points, a transformation achieving this goal is suggested, which gives algorithms that can be efficiently implemented. Application to the Steiglitz-McBride (SM) and Simple Hyperstable Adaptive Recursive Filter (SHARF) algorithms is presented. Also a modified version of Simultaneous Perturbation Stochastic Approximation (SPSA) is presented in order to get the coefficients in a lattice form more efficiently and with a lower computational cost and complexity. The results are compared with previous lattice versions of these algorithms. These previous lattice versions may fail to preserve the stability of stationary points.

  3. Bounded Linear Stability Analysis - A Time Delay Margin Estimation Approach for Adaptive Control

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.; Ishihara, Abraham K.; Krishnakumar, Kalmanje Srinlvas; Bakhtiari-Nejad, Maryam

    2009-01-01

    This paper presents a method for estimating time delay margin for model-reference adaptive control of systems with almost linear structured uncertainty. The bounded linear stability analysis method seeks to represent the conventional model-reference adaptive law by a locally bounded linear approximation within a small time window using the comparison lemma. The locally bounded linear approximation of the combined adaptive system is cast in a form of an input-time-delay differential equation over a small time window. The time delay margin of this system represents a local stability measure and is computed analytically by a matrix measure method, which provides a simple analytical technique for estimating an upper bound of time delay margin. Based on simulation results for a scalar model-reference adaptive control system, both the bounded linear stability method and the matrix measure method are seen to provide a reasonably accurate and yet not too conservative time delay margin estimation.

  4. The ARF, AUX/IAA and GH3 gene families in citrus: genome-wide identification and expression analysis during fruitlet drop from abscission zone A.

    PubMed

    Xie, Rangjin; Pang, Shaoping; Ma, Yanyan; Deng, Lie; He, Shaolan; Yi, Shilai; Lv, Qiang; Zheng, Yongqiang

    2015-12-01

    Completion of the whole genome sequencing of citrus enabled us to perform genome-wide identification and functional analysis of the gene families involved in agronomic traits and morphological diversity of citrus. In this study, 22 CitARF, 11 CitGH3 and 26 CitAUX/IAA genes were identified in citrus, respectively. Phylogenetic analysis revealed that all the genes of each gene family could be subdivided into three groups and showed strong evolutionary conservation. The GH3 and AUX/IAA gene families shrank and ARF gene family was highly conserved in the citrus genome after speciation from Arabidopsis thaliana. Tissue-specific expression profiles revealed that 54 genes were expressed in at least one tissue while just 5 genes including CitARF07, CitARF20, CitGH3.04, CitAUX/IAA25 and CitAUX/IAA26 with very low expression level in all tissues tested, suggesting that the CitARF, CitGH3 and CitAUX/IAA gene families played important roles in the development of citrus organs. In addition, our data found that the expression of 2 CitARF, 4 CitGH3 and 4 AUX/IAA genes was affected by IAA treatment, and 7 genes including, CitGH3.04, CitGH3.07, CitAUX/IAA03, CitAUX/IAA04, CitAUX/IAA18, CitAUX/IAA19 and CitAUX/IAA23 were related to fruitlet abscission. This study provides a foundation for future studies on elucidating the precise role of citrus ARF, GH3 and AUX/IAA genes in early steps of auxin signal transduction and open up a new opportunity to uncover the molecular mechanism underlying citrus fruitlet abscission.

  5. The ARF, AUX/IAA and GH3 gene families in citrus: genome-wide identification and expression analysis during fruitlet drop from abscission zone A.

    PubMed

    Xie, Rangjin; Pang, Shaoping; Ma, Yanyan; Deng, Lie; He, Shaolan; Yi, Shilai; Lv, Qiang; Zheng, Yongqiang

    2015-12-01

    Completion of the whole genome sequencing of citrus enabled us to perform genome-wide identification and functional analysis of the gene families involved in agronomic traits and morphological diversity of citrus. In this study, 22 CitARF, 11 CitGH3 and 26 CitAUX/IAA genes were identified in citrus, respectively. Phylogenetic analysis revealed that all the genes of each gene family could be subdivided into three groups and showed strong evolutionary conservation. The GH3 and AUX/IAA gene families shrank and ARF gene family was highly conserved in the citrus genome after speciation from Arabidopsis thaliana. Tissue-specific expression profiles revealed that 54 genes were expressed in at least one tissue while just 5 genes including CitARF07, CitARF20, CitGH3.04, CitAUX/IAA25 and CitAUX/IAA26 with very low expression level in all tissues tested, suggesting that the CitARF, CitGH3 and CitAUX/IAA gene families played important roles in the development of citrus organs. In addition, our data found that the expression of 2 CitARF, 4 CitGH3 and 4 AUX/IAA genes was affected by IAA treatment, and 7 genes including, CitGH3.04, CitGH3.07, CitAUX/IAA03, CitAUX/IAA04, CitAUX/IAA18, CitAUX/IAA19 and CitAUX/IAA23 were related to fruitlet abscission. This study provides a foundation for future studies on elucidating the precise role of citrus ARF, GH3 and AUX/IAA genes in early steps of auxin signal transduction and open up a new opportunity to uncover the molecular mechanism underlying citrus fruitlet abscission. PMID:25982744

  6. Adaptive-optic approach to mitigating aero-optic disturbances for a forced shear layer

    NASA Astrophysics Data System (ADS)

    Nightingale, Alice M.

    Non-uniform, variable-density fields, resulting from compressibility effects in turbulent flows, are the source of aero-optical distortions which cause significant reductions in optical system performance. As a laser beam transverses through an optically active medium, containing index-of-refraction variations, several optical phenomena occur including beam wander, image distortion, and beam defocus. When encountering a variation in the index field, light waves refract causing an otherwise planar wavefront of a laser beam to become aberrated, contributing to the adverse effects mentioned above. Adaptive-Optics (AO) is a technique used to correct for such spatially and temporally varying aberrations on an optical beam by applying a conjugate waveform correction prior to the beams transmission through the flow. Conventional AO systems are bandwidth limited by real-time processing issues and wavefront sensor limitations. Therefore, an alternative to the conventional AO approach has been proposed, developed and evaluated with the goal of overcoming such bandwidth limitations. The alternative AO system, presented throughout this document, consists of two main features; feed-forward flow control and a phase-locked-loop AO control strategy. Initially irregular, unpredictable large-scale structures within a shear layer are regularized using flow control. Subsequently, the resulting optical wavefront, and corresponding optical signal, emerging from the regularized flow becomes more periodic and predictable effectively reducing the bandwidth necessary to make real-time corrections. A phase-lock-loop controller is then used to perform real-time corrections. Wavefront corrections are estimated based upon the regularized flow, while two small aperture laser beams provide a non-intrusive means of acquiring amplitude and phase error measurements. The phase-lock-loop controller uses these signals as feedback to synchronize the deformable mirror's waveform to that of the shear

  7. Developing Coastal Adaptation to Climate Change in the New York City Infrastructure-Shed: Process, Approach, Tools, and Strategies

    NASA Technical Reports Server (NTRS)

    Rosenzweig, Cynthia; Solecki, William D.; Blake, Reginald; Bowman, Malcolm; Faris, Craig; Gornitz, Vivien; Horton, Radley; Jacob, Klaus; LeBlanc, Alice; Leichenko, Robin; Linkin, Megan; Major, David; O'Grady, Megan; Patrick, Lesley; Sussman, Edna; Yohe, Gary; Zimmerman, Rae

    2010-01-01

    While current rates of sea level rise and associated coastal flooding in the New York City region appear to be manageable by stakeholders responsible for communications, energy, transportation, and water infrastructure, projections for sea level rise and associated flooding in the future, especially those associated with rapid icemelt of the Greenland and West Antarctic Icesheets, may be beyond the range of current capacity because an extreme event might cause flooding and inundation beyond the planning and preparedness regimes. This paper describes the comprehensive process, approach, and tools developed by the New York City Panel on Climate Change (NPCC) in conjunction with the region s stakeholders who manage its critical infrastructure, much of which lies near the coast. It presents the adaptation approach and the sea-level rise and storm projections related to coastal risks developed through the stakeholder process. Climate change adaptation planning in New York City is characterized by a multi-jurisdictional stakeholder-scientist process, state-of-the-art scientific projections and mapping, and development of adaptation strategies based on a risk-management approach.

  8. IAA-producing rhizobacteria from chickpea (Cicer arietinum L.) induce changes in root architecture and increase root biomass.

    PubMed

    Fierro-Coronado, Rosario Alicia; Quiroz-Figueroa, Francisco Roberto; García-Pérez, Luz María; Ramírez-Chávez, Enrique; Molina-Torres, Jorge; Maldonado-Mendoza, Ignacio Eduardo

    2014-10-01

    Rhizobacteria promote and have beneficial effects on plant growth, making them useful to agriculture. Nevertheless, the rhizosphere of the chickpea plant has not been extensively examined. The aim of the present study was to select indole-3-acetic acid (IAA) producing rhizobacteria from the rhizosphere of chickpea plants for their potential use as biofertilizers. After obtaining a collection of 864 bacterial isolates, we performed a screen using the Salkowski reaction for the presence of auxin compounds (such as IAA) in bacterial Luria-Bertani supernatant (BLBS). Our results demonstrate that the Salkowski reaction has a greater specificity for detecting IAA than other tested auxins. Ten bacterial isolates displaying a wide range of auxin accumulation were selected, producing IAA levels of 5 to 90 μmol/L (according to the Salkowski reaction). Bacterial isolates were identified on the basis of 16S rDNA partial sequences: 9 isolates belonged to Enterobacter, and 1 isolate was classified as Serratia. The effect of BLBS on root morphology was evaluated in Arabidopsis thaliana. IAA production by rhizobacteria was confirmed by means of a DR5::GFP construct that is responsive to IAA, and also by HPLC-GC/MS. Finally, we observed that IAA secreted by rhizobacteria (i) modified the root architecture of A. thaliana, (ii) caused an increase in chickpea root biomass, and (iii) activated the green fluorescent protein (GFP) reporter gene driven by the DR5 promoter. These findings provide evidence that these novel bacterial isolates may be considered as putative plant-growth-promoting rhizobacteria modifying root architecture and increasing root biomass.

  9. Approaching sign language test construction: adaptation of the German sign language receptive skills test.

    PubMed

    Haug, Tobias

    2011-01-01

    There is a current need for reliable and valid test instruments in different countries in order to monitor deaf children's sign language acquisition. However, very few tests are commercially available that offer strong evidence for their psychometric properties. A German Sign Language (DGS) test focusing on linguistic structures that are acquired in preschool- and school-aged children (4-8 years old) is urgently needed. Using the British Sign Language Receptive Skills Test, that has been standardized and has sound psychometric properties, as a template for adaptation thus provides a starting point for tests of a sign language that is less documented, such as DGS. This article makes a novel contribution to the field by examining linguistic, cultural, and methodological issues in the process of adapting a test from the source language to the target language. The adapted DGS test has sound psychometric properties and provides the basis for revision prior to standardization. PMID:21208998

  10. Adaptive cluster expansion approach for predicting the structure evolution of graphene oxide

    SciTech Connect

    Li, Xi-Bo; Guo, Pan; Wang, D.; Liu, Li-Min; Zhang, Yongsheng

    2014-12-14

    An adaptive cluster expansion (CE) method is used to explore surface adsorption and growth processes. Unlike the traditional CE method, suitable effective cluster interaction (ECI) parameters are determined, and then the selected fixed number of ECIs is continually optimized to predict the stable configurations with gradual increase of adatom coverage. Comparing with traditional CE method, the efficiency of the adaptive CE method could be greatly enhanced. As an application, the adsorption and growth of oxygen atoms on one side of pristine graphene was carefully investigated using this method in combination with first-principles calculations. The calculated results successfully uncover the structural evolution of graphene oxide for the different numbers of oxygen adatoms on graphene. The aggregation behavior of the stable configurations for different oxygen adatom coverages is revealed for increasing coverages of oxygen atoms. As a targeted method, adaptive CE can also be applied to understand the evolution of other surface adsorption and growth processes.

  11. Automatic off-body overset adaptive Cartesian mesh method based on an octree approach

    SciTech Connect

    Peron, Stephanie; Benoit, Christophe

    2013-01-01

    This paper describes a method for generating adaptive structured Cartesian grids within a near-body/off-body mesh partitioning framework for the flow simulation around complex geometries. The off-body Cartesian mesh generation derives from an octree structure, assuming each octree leaf node defines a structured Cartesian block. This enables one to take into account the large scale discrepancies in terms of resolution between the different bodies involved in the simulation, with minimum memory requirements. Two different conversions from the octree to Cartesian grids are proposed: the first one generates Adaptive Mesh Refinement (AMR) type grid systems, and the second one generates abutting or minimally overlapping Cartesian grid set. We also introduce an algorithm to control the number of points at each adaptation, that automatically determines relevant values of the refinement indicator driving the grid refinement and coarsening. An application to a wing tip vortex computation assesses the capability of the method to capture accurately the flow features.

  12. Approaching sign language test construction: adaptation of the German sign language receptive skills test.

    PubMed

    Haug, Tobias

    2011-01-01

    There is a current need for reliable and valid test instruments in different countries in order to monitor deaf children's sign language acquisition. However, very few tests are commercially available that offer strong evidence for their psychometric properties. A German Sign Language (DGS) test focusing on linguistic structures that are acquired in preschool- and school-aged children (4-8 years old) is urgently needed. Using the British Sign Language Receptive Skills Test, that has been standardized and has sound psychometric properties, as a template for adaptation thus provides a starting point for tests of a sign language that is less documented, such as DGS. This article makes a novel contribution to the field by examining linguistic, cultural, and methodological issues in the process of adapting a test from the source language to the target language. The adapted DGS test has sound psychometric properties and provides the basis for revision prior to standardization.

  13. Evaluation of Online/Offline Image Guidance/Adaptation Approaches for Prostate Cancer Radiation Therapy

    SciTech Connect

    Qin, An; Sun, Ying; Liang, Jian; Yan, Di

    2015-04-01

    Purpose: To evaluate online/offline image-guided/adaptive treatment techniques for prostate cancer radiation therapy with daily cone-beam CT (CBCT) imaging. Methods and Materials: Three treatment techniques were evaluated retrospectively using daily pre- and posttreatment CBCT images on 22 prostate cancer patients. Prostate, seminal vesicles (SV), rectal wall, and bladder were delineated on all CBCT images. For each patient, a pretreatment intensity modulated radiation therapy plan with clinical target volume (CTV) = prostate + SV and planning target volume (PTV) = CTV + 3 mm was created. The 3 treatment techniques were as follows: (1) Daily Correction: The pretreatment intensity modulated radiation therapy plan was delivered after online CBCT imaging, and position correction; (2) Online Planning: Daily online inverse plans with 3-mm CTV-to-PTV margin were created using online CBCT images, and delivered; and (3) Hybrid Adaption: Daily Correction plus an offline adaptive inverse planning performed after the first week of treatment. The adaptive plan was delivered for all remaining 15 fractions. Treatment dose for each technique was constructed using the daily posttreatment CBCT images via deformable image registration. Evaluation was performed using treatment dose distribution in target and critical organs. Results: Treatment equivalent uniform dose (EUD) for the CTV was within [85.6%, 100.8%] of the pretreatment planned target EUD for Daily Correction; [98.7%, 103.0%] for Online Planning; and [99.2%, 103.4%] for Hybrid Adaptation. Eighteen percent of the 22 patients in Daily Correction had a target dose deficiency >5%. For rectal wall, the mean ± SD of the normalized EUD was 102.6% ± 2.7% for Daily Correction, 99.9% ± 2.5% for Online Planning, and 100.6% ± 2.1% for Hybrid Adaptation. The mean ± SD of the normalized bladder EUD was 108.7% ± 8.2% for Daily Correction, 92.7% ± 8.6% for Online Planning, and 89.4% ± 10.8% for Hybrid

  14. Modeling and control of nonlinear systems using novel fuzzy wavelet networks: The output adaptive control approach

    NASA Astrophysics Data System (ADS)

    Mousavi, Seyyed Hossein; Noroozi, Navid; Safavi, Ali Akbar; Ebadat, Afrooz

    2011-09-01

    This paper proposes an observer based self-structuring robust adaptive fuzzy wave-net (FWN) controller for a class of nonlinear uncertain multi-input multi-output systems. The control signal is comprised of two parts. The first part arises from an adaptive fuzzy wave-net based controller that approximates the system structural uncertainties. The second part comes from a robust H∞ based controller that is used to attenuate the effect of function approximation error and disturbance. Moreover, a new self structuring algorithm is proposed to determine the location of basis functions. Simulation results are provided for a two DOF robot to show the effectiveness of the proposed method.

  15. An adaptive approach to the dynamic allocation of buffer storage. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Crooke, S. C.

    1970-01-01

    Several strategies for the dynamic allocation of buffer storage are simulated and compared. The basic algorithms investigated, using actual statistics observed in the Univac 1108 EXEC 8 System, include the buddy method and the first-fit method. Modifications are made to the basic methods in an effort to improve and to measure allocation performance. A simulation model of an adaptive strategy is developed which permits interchanging the two different methods, the buddy and the first-fit methods with some modifications. Using an adaptive strategy, each method may be employed in the statistical environment in which its performance is superior to the other method.

  16. A Multiple Objective Test Assembly Approach for Exposure Control Problems in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Veldkamp, Bernard P.; Verschoor, Angela J.; Eggen, Theo J. H. M.

    2010-01-01

    Overexposure and underexposure of items in the bank are serious problems in operational computerized adaptive testing (CAT) systems. These exposure problems might result in item compromise, or point at a waste of investments. The exposure control problem can be viewed as a test assembly problem with multiple objectives. Information in the test has…

  17. Constructive, Self-Regulated, Situated, and Collaborative Learning: An Approach for the Acquisition of Adaptive Competence

    ERIC Educational Resources Information Center

    de Corte, Erik

    2012-01-01

    In today's learning society, education must focus on fostering adaptive competence (AC) defined as the ability to apply knowledge and skills flexibly in different contexts. In this article, four major types of learning are discussed--constructive, self-regulated, situated, and collaborative--in relation to what students must learn in order to…

  18. Values and Subjective Mental Health in America: A Social Adaptation Approach.

    ERIC Educational Resources Information Center

    Kahle, Lynn R.; And Others

    Although surveys of mental health involve some controversy, a significant relationship between values and mental health appears to exist. To study the adaption of individuals with alternative values to their psychological worlds, over 2,000 adults identified their most important values. Alcohol abuse, drug abuse, dizziness, anxiety, and general…

  19. An adaptive approach to computing the spectrum and mean frequency of Doppler signals.

    PubMed

    Herment, A; Giovannelli, J F

    1995-01-01

    Modern ultrasound Doppler systems are facing the problem of processing increasingly shorter data sets. Spectral analysis of the strongly nonstationary Doppler signal needs to shorten the analysis window while maintaining a low variance and high resolution spectrum. Color flow imaging requires estimation of the Doppler mean frequency from even shorter Doppler data sets to obtain both a high frame rate and high spatial resolution. We reconsider these two estimation problems in light of adaptive methods. A regularized parametric method for spectral analysis as well as an adapted mean frequency estimator are developed. The choice of the adaptive criterion is then addressed and adaptive spectral and mean frequency estimators are developed to minimize the mean square error on estimation in the presence of noise. Two suboptimal spectral and mean-frequency estimators are then derived for real-time applications. Finally, their performance is compared to that of both the FFT based periodogram and the AR parametric spectral analysis for the spectral estimator, and, to both the correlation angle and the Kristoffersen's [8] estimators for the mean frequency estimator using Doppler data recorded in vitro. PMID:7638930

  20. Difference, Adapted Physical Activity and Human Development: Potential Contribution of Capabilities Approach

    ERIC Educational Resources Information Center

    Silva, Carla Filomena; Howe, P. David

    2012-01-01

    This paper is a call to Adapted Physical Activity (APA) professionals to increase the reflexive nature of their practice. Drawing upon Foucault's concept of governmentality (1977) APA action may work against its own publicized goals of empowerment and self-determination. To highlight these inconsistencies, we will draw upon historical and social…

  1. An Approach for Automatic Generation of Adaptive Hypermedia in Education with Multilingual Knowledge Discovery Techniques

    ERIC Educational Resources Information Center

    Alfonseca, Enrique; Rodriguez, Pilar; Perez, Diana

    2007-01-01

    This work describes a framework that combines techniques from Adaptive Hypermedia and Natural Language processing in order to create, in a fully automated way, on-line information systems from linear texts in electronic format, such as textbooks. The process is divided into two steps: an "off-line" processing step, which analyses the source text,…

  2. Peers as Resources for Learning: A Situated Learning Approach to Adapted Physical Activity in Rehabilitation

    ERIC Educational Resources Information Center

    Standal, Oyvind F.; Jespersen, Ejgil

    2008-01-01

    The purpose of this study was to investigate the learning that takes place when people with disabilities interact in a rehabilitation context. Data were generated through in-depth interviews and close observations in a 2 one-half week-long rehabilitation program, where the participants learned both wheelchair skills and adapted physical…

  3. Who Needs Contingency Approaches and Guidelines in Order to Adapt Vague Management Ideas?

    ERIC Educational Resources Information Center

    Ortenblad, Anders

    2010-01-01

    The purpose of this conceptual paper is to question the assumption that the general idea of the learning organisation needs to be adapted to the specific context before it can be put into practical use. It is suggested that there are lots of ways to use management ideas, other than implementing them in the practice of organisations. It is further…

  4. Can Approaches to Research in Art and Design Be Beneficially Adapted for Research into Higher Education?

    ERIC Educational Resources Information Center

    Trowler, Paul

    2013-01-01

    This paper examines the research practices in Art and Design that are distinctively different from those common in research into higher education outside those fields. It considers whether and what benefit could be derived from their adaptation by the latter. The paper also examines the factors that are conducive and obstructive to adaptive…

  5. An Approach to Evaluating Adolescent Adaptive Processes: Validity of an Interview-Based Measure.

    ERIC Educational Resources Information Center

    Beardslee, William R.; And Others

    1986-01-01

    An initial exploration of the validity of 15 scales designed to assess adaptive ego processes in adolescence is presented. Diabetic youngsters, psychiatric patients, and high school students with no illness are compared using the scales. Correlations are found between the scales and a separate, conceptually related measure of ego development.…

  6. A hierarchical Bayesian approach to adaptive vision testing: A case study with the contrast sensitivity function

    PubMed Central

    Gu, Hairong; Kim, Woojae; Hou, Fang; Lesmes, Luis Andres; Pitt, Mark A.; Lu, Zhong-Lin; Myung, Jay I.

    2016-01-01

    Measurement efficiency is of concern when a large number of observations are required to obtain reliable estimates for parametric models of vision. The standard entropy-based Bayesian adaptive testing procedures addressed the issue by selecting the most informative stimulus in sequential experimental trials. Noninformative, diffuse priors were commonly used in those tests. Hierarchical adaptive design optimization (HADO; Kim, Pitt, Lu, Steyvers, & Myung, 2014) further improves the efficiency of the standard Bayesian adaptive testing procedures by constructing an informative prior using data from observers who have already participated in the experiment. The present study represents an empirical validation of HADO in estimating the human contrast sensitivity function. The results show that HADO significantly improves the accuracy and precision of parameter estimates, and therefore requires many fewer observations to obtain reliable inference about contrast sensitivity, compared to the method of quick contrast sensitivity function (Lesmes, Lu, Baek, & Albright, 2010), which uses the standard Bayesian procedure. The improvement with HADO was maintained even when the prior was constructed from heterogeneous populations or a relatively small number of observers. These results of this case study support the conclusion that HADO can be used in Bayesian adaptive testing by replacing noninformative, diffuse priors with statistically justified informative priors without introducing unwanted bias. PMID:27105061

  7. Assessing the effects of heavy metals in ACC deaminase and IAA production on plant growth-promoting bacteria.

    PubMed

    Carlos, Mendoza-Hernández José; Stefani, Perea-Vélez Yazmin; Janette, Arriola-Morales; Melani, Martínez-Simón Sara; Gabriela, Pérez-Osorio

    2016-01-01

    This study poses a methodology in order to simultaneously quantify ACC deaminase and IAA levels in the same culture medium. Ten bacterial strains isolated from plant rhizosphere naturally settled in mining residues were chosen. These bacterial strains were characterized as PGPB, and all of them showed at least three characteristics (indole-3 acetic acid and siderophore production, ACC deaminase enzyme activity, and inorganic phosphate solubilization). Taxonomic identification showed that the strains belong to Enterobacter, Serratia, Klebsiella, and Escherichia genera. Similarly, both the ACC deaminase enzyme activity and the IAA synthesis in the presence of Cu, As, Pb, Ni, Cd, and Mn were measured. The results showed that both the ACC deaminase enzyme activity and the IAA synthesis were higher with the Pb, As, and Cu treatments than with the Escherichia N16, Enterobacter K131, Enterobacter N9, and Serratia K120 control treatments. On the other hand, Ni, Cd, and Mn negatively affected both the ACC deaminase enzyme activity and the IAA production on every bacterium except on the Klebsiella Mc173 strain. Serratia K120 bacterium got a positive correlation between ACC deaminase and IAA in the presence of every heavy metal, and it also promoted Helianthus annuus plant growth, showing a potential use in phytoremediation systems.

  8. Assessing the effects of heavy metals in ACC deaminase and IAA production on plant growth-promoting bacteria.

    PubMed

    Carlos, Mendoza-Hernández José; Stefani, Perea-Vélez Yazmin; Janette, Arriola-Morales; Melani, Martínez-Simón Sara; Gabriela, Pérez-Osorio

    2016-01-01

    This study poses a methodology in order to simultaneously quantify ACC deaminase and IAA levels in the same culture medium. Ten bacterial strains isolated from plant rhizosphere naturally settled in mining residues were chosen. These bacterial strains were characterized as PGPB, and all of them showed at least three characteristics (indole-3 acetic acid and siderophore production, ACC deaminase enzyme activity, and inorganic phosphate solubilization). Taxonomic identification showed that the strains belong to Enterobacter, Serratia, Klebsiella, and Escherichia genera. Similarly, both the ACC deaminase enzyme activity and the IAA synthesis in the presence of Cu, As, Pb, Ni, Cd, and Mn were measured. The results showed that both the ACC deaminase enzyme activity and the IAA synthesis were higher with the Pb, As, and Cu treatments than with the Escherichia N16, Enterobacter K131, Enterobacter N9, and Serratia K120 control treatments. On the other hand, Ni, Cd, and Mn negatively affected both the ACC deaminase enzyme activity and the IAA production on every bacterium except on the Klebsiella Mc173 strain. Serratia K120 bacterium got a positive correlation between ACC deaminase and IAA in the presence of every heavy metal, and it also promoted Helianthus annuus plant growth, showing a potential use in phytoremediation systems. PMID:27296962

  9. Solanum lycopersicum IAA15 functions in the 2,4-dichlorophenoxyacetic acid herbicide mechanism of action by mediating abscisic acid signalling.

    PubMed

    Xu, Tao; Wang, Yanling; Liu, Xin; Gao, Song; Qi, Mingfang; Li, Tianlai

    2015-07-01

    2,4-Dichlorophenoxyacetic acid (2,4-D), an important plant growth regulator, is the herbicide most commonly used worldwide to control weeds. However, broad-leaf fruits and vegetables are extremely sensitive to herbicides, which can cause damage and result in lost crops when applied in a manner inconsistent with the directions. Despite detailed knowledge of the mechanism of 2,4-D, the regulation of auxin signalling is still unclear. For example, although the major mediators of auxin signalling, including auxin/indole acetic acid (AUX/IAA) proteins and auxin response factors (ARFs), are known to mediate auxinic herbicides, the underlying mechanisms are still unclear. In this study, the effects of 2,4-D on AUX/IAA gene expression in tomato were investigated, and the two most notably up-regulated genes, SlIAA15 and SlIAA29, were selected for further study. Western blotting revealed the substantial accumulation of both SlIAA15 and SlIAA29, and the expression levels of the corresponding genes were increased following abscisic acid (ABA) and ethylene treatment. Overexpressing SlIAA15, but not SlIAA29, induced a 2,4-D herbicide damage phenotype. The 35S::SlIAA15 line exhibited a strong reduction in leaf stomatal density and altered expression of some R2R3 MYB genes that are putatively involved in the regulation of stomatal differentiation. Further study revealed that root elongation in 35S::SlIAA15 was sensitive to ABA treatment, and was most probably due to the altered expression of an ABA signal transduction gene. In addition, the altered auxin sensitivities of SlIAA15 transformants were also explored. These results suggested that SlIAA15 plays an important role in determining the effects of the herbicide 2,4-D.

  10. ASICs Approach for the Implementation of a Symmetric Triangular Fuzzy Coprocessor and Its Application to Adaptive Filtering

    NASA Technical Reports Server (NTRS)

    Starks, Scott; Abdel-Hafeez, Saleh; Usevitch, Bryan

    1997-01-01

    This paper discusses the implementation of a fuzzy logic system using an ASICs design approach. The approach is based upon combining the inherent advantages of symmetric triangular membership functions and fuzzy singleton sets to obtain a novel structure for fuzzy logic system application development. The resulting structure utilizes a fuzzy static RAM to store the rule-base and the end-points of the triangular membership functions. This provides advantages over other approaches in which all sampled values of membership functions for all universes must be stored. The fuzzy coprocessor structure implements the fuzzification and defuzzification processes through a two-stage parallel pipeline architecture which is capable of executing complex fuzzy computations in less than 0.55us with an accuracy of more than 95%, thus making it suitable for a wide range of applications. Using the approach presented in this paper, a fuzzy logic rule-base can be directly downloaded via a host processor to an onchip rule-base memory with a size of 64 words. The fuzzy coprocessor's design supports up to 49 rules for seven fuzzy membership functions associated with each of the chip's two input variables. This feature allows designers to create fuzzy logic systems without the need for additional on-board memory. Finally, the paper reports on simulation studies that were conducted for several adaptive filter applications using the least mean squared adaptive algorithm for adjusting the knowledge rule-base.

  11. A Cartesian, cell-based approach for adaptively-refined solutions of the Euler and Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Coirier, William J.; Powell, Kenneth G.

    1995-01-01

    A Cartesian, cell-based approach for adaptively-refined solutions of the Euler and Navier-Stokes equations in two dimensions is developed and tested. Grids about geometrically complicated bodies are generated automatically, by recursive subdivision of a single Cartesian cell encompassing the entire flow domain. Where the resulting cells intersect bodies, N-sided 'cut' cells are created using polygon-clipping algorithms. The grid is stored in a binary-tree data structure which provides a natural means of obtaining cell-to-cell connectivity and of carrying out solution-adaptive mesh refinement. The Euler and Navier-Stokes equations are solved on the resulting grids using a finite-volume formulation. The convective terms are upwinded: A gradient-limited, linear reconstruction of the primitive variables is performed, providing input states to an approximate Riemann solver for computing the fluxes between neighboring cells. The more robust of a series of viscous flux functions is used to provide the viscous fluxes at the cell interfaces. Adaptively-refined solutions of the Navier-Stokes equations using the Cartesian, cell-based approach are obtained and compared to theory, experiment and other accepted computational results for a series of low and moderate Reynolds number flows.

  12. A Cartesian, cell-based approach for adaptively-refined solutions of the Euler and Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Coirier, William J.; Powell, Kenneth G.

    1994-01-01

    A Cartesian, cell-based approach for adaptively-refined solutions of the Euler and Navier-Stokes equations in two dimensions is developed and tested. Grids about geometrically complicated bodies are generated automatically, by recursive subdivision of a single Cartesian cell encompassing the entire flow domain. Where the resulting cells intersect bodies, N-sided 'cut' cells are created using polygon-clipping algorithms. The grid is stored in a binary-tree structure which provides a natural means of obtaining cell-to-cell connectivity and of carrying out solution-adaptive mesh refinement. The Euler and Navier-Stokes equations are solved on the resulting grids using a finite-volume formulation. The convective terms are upwinded: a gradient-limited, linear reconstruction of the primitive variables is performed, providing input states to an approximate Riemann solver for computing the fluxes between neighboring cells. The more robust of a series of viscous flux functions is used to provide the viscous fluxes at the cell interfaces. Adaptively-refined solutions of the Navier-Stokes equations using the Cartesian, cell-based approach are obtained and compared to theory, experiment, and other accepted computational results for a series of low and moderate Reynolds number flows.

  13. Adaptive fuzzy output-feedback controller design for nonlinear systems via backstepping and small-gain approach.

    PubMed

    Liu, Zhi; Wang, Fang; Zhang, Yun; Chen, Xin; Chen, C L Philip

    2014-10-01

    This paper focuses on an input-to-state practical stability (ISpS) problem of nonlinear systems which possess unmodeled dynamics in the presence of unstructured uncertainties and dynamic disturbances. The dynamic disturbances depend on the states and the measured output of the system, and its assumption conditions are relaxed compared with the common restrictions. Based on an input-driven filter, fuzzy logic systems are directly used to approximate the unknown and desired control signals instead of the unknown nonlinear functions, and an integrated backstepping technique is used to design an adaptive output-feedback controller that ensures robustness with respect to unknown parameters and uncertain nonlinearities. This paper, by applying the ISpS theory and the generalized small-gain approach, shows that the proposed adaptive fuzzy controller guarantees the closed-loop system being semi-globally uniformly ultimately bounded. A main advantage of the proposed controller is that it contains only three adaptive parameters that need to be updated online, no matter how many states there are in the systems. Finally, the effectiveness of the proposed approach is illustrated by two simulation examples. PMID:25222716

  14. The DefH9-iaaM-containing construct efficiently induces parthenocarpy in cucumber.

    PubMed

    Yin, Zhimin; Malinowski, Robert; Ziółkowska, Agnieszka; Sommer, Hans; Plcader, Wojciech; Malepszy, Stefan

    2006-01-01

    Parthenocarpy (seedless fruits) is a desirable trait that has been achieved in many plant cultivars. We generated parthenocarpic cucumber fruits by introducing the chimeric DefH9-iaaM construct into the cucumber genome using an Agrobacterium tumefaciens-mediated protocol. The construct consists of the DefH9 promoter from Antirrhinum majus and the iaaM coding sequence from Pseudomonas syringae. Transgenic plants were obtained from nine independent transformation events: half of these were tetraploid and did not produce seeds following self-pollination, while the remaining half were capable of displaying parthenocarpy in the subsequent reproductive generation. Of the fruits produced by the transgenic lines, 70-90% were parthenocarpic. The segregation of the marker gene in the transgenic T(1) progeny indicated single gene inheritance. The seed set in the transgenic lines and their F(1) hybrids was lower than in the non-transgenic control plants. Some of the methodological details and the practical significance of the results are discussed. PMID:16847572

  15. Down-regulation of SlIAA15 in tomato altered stem xylem development and production of volatile compounds in leaf exudates.

    PubMed

    Deng, Wei; Yan, Fang; Liu, Minchun; Wang, Xinyu; Li, Zhengguo

    2012-08-01

    The Aux/IAA family genes encode short-lived nuclear proteins that function as transcriptional regulators in auxin signal transduction. Aux/IAA genes have been reported to control many processes of plant development. Our recent study showed that down-regulation of SlIAA15 in tomato reduced apical dominance, altered pattern of axillary shoot development, increased lateral root formation and leaves thickness. The SlIAA15 suppressed lines display strong reduction of trichome density, suggesting that SlIAA15 is involved in trichome formation. Here, we reported that SlIAA15-suppressed transgenic lines display increased number of xylem cells compared to wild-type plants. Moreover, the monoterpene content in trichome exudates are significantly reduced in SlIAA15 down-regulated leaves. The results provide the roles of SlIAA15 in production of volatile compounds in leaf exudates and xylem development, clearly indicating that members of the Aux/IAA gene family can play distinct and specific functions.  PMID:22836503

  16. Kinetic Boltzmann approach adapted for modeling highly ionized matter created by x-ray irradiation of a solid

    NASA Astrophysics Data System (ADS)

    Ziaja, Beata; Saxena, Vikrant; Son, Sang-Kil; Medvedev, Nikita; Barbrel, Benjamin; Woloncewicz, Bianca; Stransky, Michal

    2016-05-01

    We report on the kinetic Boltzmann approach adapted for simulations of highly ionized matter created from a solid by its x-ray irradiation. X rays can excite inner-shell electrons, which leads to the creation of deeply lying core holes. Their relaxation, especially in heavier elements, can take complicated paths, leading to a large number of active configurations. Their number can be so large that solving the set of respective evolution equations becomes computationally inefficient and another modeling approach should be used instead. To circumvent this complexity, the commonly used continuum models employ a superconfiguration scheme. Here, we propose an alternative approach which still uses "true" atomic configurations but limits their number by restricting the sample relaxation to the predominant relaxation paths. We test its reliability, performing respective calculations for a bulk material consisting of light atoms and comparing the results with a full calculation including all relaxation paths. Prospective application for heavy elements is discussed.

  17. Kinetic Boltzmann approach adapted for modeling highly ionized matter created by x-ray irradiation of a solid.

    PubMed

    Ziaja, Beata; Saxena, Vikrant; Son, Sang-Kil; Medvedev, Nikita; Barbrel, Benjamin; Woloncewicz, Bianca; Stransky, Michal

    2016-05-01

    We report on the kinetic Boltzmann approach adapted for simulations of highly ionized matter created from a solid by its x-ray irradiation. X rays can excite inner-shell electrons, which leads to the creation of deeply lying core holes. Their relaxation, especially in heavier elements, can take complicated paths, leading to a large number of active configurations. Their number can be so large that solving the set of respective evolution equations becomes computationally inefficient and another modeling approach should be used instead. To circumvent this complexity, the commonly used continuum models employ a superconfiguration scheme. Here, we propose an alternative approach which still uses "true" atomic configurations but limits their number by restricting the sample relaxation to the predominant relaxation paths. We test its reliability, performing respective calculations for a bulk material consisting of light atoms and comparing the results with a full calculation including all relaxation paths. Prospective application for heavy elements is discussed. PMID:27300998

  18. A Monte Carlo simulation based two-stage adaptive resonance theory mapping approach for offshore oil spill vulnerability index classification.

    PubMed

    Li, Pu; Chen, Bing; Li, Zelin; Zheng, Xiao; Wu, Hongjing; Jing, Liang; Lee, Kenneth

    2014-09-15

    In this paper, a Monte Carlo simulation based two-stage adaptive resonance theory mapping (MC-TSAM) model was developed to classify a given site into distinguished zones representing different levels of offshore Oil Spill Vulnerability Index (OSVI). It consisted of an adaptive resonance theory (ART) module, an ART Mapping module, and a centroid determination module. Monte Carlo simulation was integrated with the TSAM approach to address uncertainties that widely exist in site conditions. The applicability of the proposed model was validated by classifying a large coastal area, which was surrounded by potential oil spill sources, based on 12 features. Statistical analysis of the results indicated that the classification process was affected by multiple features instead of one single feature. The classification results also provided the least or desired number of zones which can sufficiently represent the levels of offshore OSVI in an area under uncertainty and complexity, saving time and budget in spill monitoring and response. PMID:25044043

  19. An auto-adaptive optimization approach for targeting nonpoint source pollution control practices

    NASA Astrophysics Data System (ADS)

    Chen, Lei; Wei, Guoyuan; Shen, Zhenyao

    2015-10-01

    To solve computationally intensive and technically complex control of nonpoint source pollution, the traditional genetic algorithm was modified into an auto-adaptive pattern, and a new framework was proposed by integrating this new algorithm with a watershed model and an economic module. Although conceptually simple and comprehensive, the proposed algorithm would search automatically for those Pareto-optimality solutions without a complex calibration of optimization parameters. The model was applied in a case study in a typical watershed of the Three Gorges Reservoir area, China. The results indicated that the evolutionary process of optimization was improved due to the incorporation of auto-adaptive parameters. In addition, the proposed algorithm outperformed the state-of-the-art existing algorithms in terms of convergence ability and computational efficiency. At the same cost level, solutions with greater pollutant reductions could be identified. From a scientific viewpoint, the proposed algorithm could be extended to other watersheds to provide cost-effective configurations of BMPs.

  20. An auto-adaptive optimization approach for targeting nonpoint source pollution control practices.

    PubMed

    Chen, Lei; Wei, Guoyuan; Shen, Zhenyao

    2015-10-21

    To solve computationally intensive and technically complex control of nonpoint source pollution, the traditional genetic algorithm was modified into an auto-adaptive pattern, and a new framework was proposed by integrating this new algorithm with a watershed model and an economic module. Although conceptually simple and comprehensive, the proposed algorithm would search automatically for those Pareto-optimality solutions without a complex calibration of optimization parameters. The model was applied in a case study in a typical watershed of the Three Gorges Reservoir area, China. The results indicated that the evolutionary process of optimization was improved due to the incorporation of auto-adaptive parameters. In addition, the proposed algorithm outperformed the state-of-the-art existing algorithms in terms of convergence ability and computational efficiency. At the same cost level, solutions with greater pollutant reductions could be identified. From a scientific viewpoint, the proposed algorithm could be extended to other watersheds to provide cost-effective configurations of BMPs.

  1. Toward a systems-oriented approach to the role of the extended amygdala in adaptive responding.

    PubMed

    Waraczynski, Meg

    2016-09-01

    Research into the structure and function of the basal forebrain macrostructure called the extended amygdala (EA) has recently seen considerable growth. This paper reviews that work, with the objectives of identifying underlying themes and developing a common goal towards which investigators of EA function might work. The paper begins with a brief review of the structure and the ontological and phylogenetic origins of the EA. It continues with a review of research into the role of the EA in both aversive and appetitive states, noting that these two seemingly disparate avenues of research converge on the concept of reinforcement - either negative or positive - of adaptive responding. These reviews lead to a proposal as to where the EA may fit in the organization of the basal forebrain, and an invitation to investigators to place their findings in a unifying conceptual framework of the EA as a collection of neural ensembles that mediate adaptive responding. PMID:27216212

  2. Defect structure of a nematic liquid crystal around a spherical particle: adaptive mesh refinement approach.

    PubMed

    Fukuda, Jun-ichi; Yoneya, Makoto; Yokoyama, Hiroshi

    2002-04-01

    We investigate numerically the structure of topological defects close to a spherical particle immersed in a uniformly aligned nematic liquid crystal. To this end we have implemented an adaptive mesh refinement scheme in an axi-symmetric three-dimensional system, which makes it feasible to take into account properly the large length scale difference between the particle and the topological defects. The adaptive mesh refinement scheme proves to be quite efficient and useful in the investigation of not only the macroscopic properties such as the defect position but also the fine structure of defects. It can be shown that a hyperbolic hedgehog that accompanies a particle with strong homeotropic anchoring takes the structure of a ring.

  3. Adaptive finite-element approach for analysis of bone/prosthesis interaction.

    PubMed

    Hübsch, P F; Middleton, J; Meroi, E A; Natali, A N

    1995-01-01

    The study uses the finite-element method to analyse the stress field in a perfectly bonded hip prosthesis arising from loading through body weight. Special attention is paid to the accuracy of the numerical analysis, and adaptive mesh refinement is introduced to reduce the discretisation error. The finite-element procedure developed is especially well suited to analyse the behaviour of a bonded interface as it is capable of calculating accurately the stress at the nodal positions while satisfying the natural discontinuity in the stress field at this location. An orthotropic material model is used for the representation of the behaviour of the bone, and an axisymmetric geometry with non-symmetrical loading is adopted for the analysis. The results demonstrate the usefulness of adaptive mesh refinement and the significance of adopting anisotropic material modelling in the context of tissue/prosthesis interaction.

  4. An alternative approach for adaptive real-time control using a nonparametric neural network

    SciTech Connect

    Alves da Silva, A.P.; Nascimento, P.C.; Lambert-Torres, G.; Borges da Silva, L.E.

    1995-12-31

    This paper presents a nonparametric Artificial Neural Network (ANN) model for adaptive control of nonlinear systems. The proposed ANN, Functional Polynomial Network (FPN), mixes the concept of orthogonal basis functions with the idea of polynomial networks. A combination of orthogonal functions can be used to produce a desired mapping. However, there is no way besides trial and error to choose which orthogonal functions should be selected. Polynomial nets can be used for function approximation, but, it is not easy to set the order of the activation function. The combination of the two concepts produces a very powerful ANN model due to the automatic input selection capability of the polynomial networks. The proposed FPN has been tested for speed control of a DC motor. The results have been compared with the ones provided by an indirect adaptive control scheme based on multilayer perceptrons trained by backpropagation.

  5. A Neural Network Approach to Intention Modeling for User-Adapted Conversational Agents

    PubMed Central

    Griol, David

    2016-01-01

    Spoken dialogue systems have been proposed to enable a more natural and intuitive interaction with the environment and human-computer interfaces. In this contribution, we present a framework based on neural networks that allows modeling of the user's intention during the dialogue and uses this prediction to dynamically adapt the dialogue model of the system taking into consideration the user's needs and preferences. We have evaluated our proposal to develop a user-adapted spoken dialogue system that facilitates tourist information and services and provide a detailed discussion of the positive influence of our proposal in the success of the interaction, the information and services provided, and the quality perceived by the users. PMID:26819592

  6. Adaptive Developmental Delay in Chagas Disease Vectors: An Evolutionary Ecology Approach

    PubMed Central

    Menu, Frédéric; Ginoux, Marine; Rajon, Etienne; Lazzari, Claudio R.; Rabinovich, Jorge E.

    2010-01-01

    Background The developmental time of vector insects is important in population dynamics, evolutionary biology, epidemiology and in their responses to global climatic change. In the triatomines (Triatominae, Reduviidae), vectors of Chagas disease, evolutionary ecology concepts, which may allow for a better understanding of their biology, have not been applied. Despite delay in the molting in some individuals observed in triatomines, no effort was made to explain this variability. Methodology We applied four methods: (1) an e-mail survey sent to 30 researchers with experience in triatomines, (2) a statistical description of the developmental time of eleven triatomine species, (3) a relationship between development time pattern and climatic inter-annual variability, (4) a mathematical optimization model of evolution of developmental delay (diapause). Principal Findings 85.6% of responses informed on prolonged developmental times in 5th instar nymphs, with 20 species identified with remarkable developmental delays. The developmental time analysis showed some degree of bi-modal pattern of the development time of the 5th instars in nine out of eleven species but no trend between development time pattern and climatic inter-annual variability was observed. Our optimization model predicts that the developmental delays could be due to an adaptive risk-spreading diapause strategy, only if survival throughout the diapause period and the probability of random occurrence of “bad” environmental conditions are sufficiently high. Conclusions/Significance Developmental delay may not be a simple non-adaptive phenotypic plasticity in development time, and could be a form of adaptive diapause associated to a physiological mechanism related to the postponement of the initiation of reproduction, as an adaptation to environmental stochasticity through a spreading of risk (bet-hedging) strategy. We identify a series of parameters that can be measured in the field and laboratory to test

  7. Finite element/finite volume approaches with adaptive time stepping strategies for transient thermal problems

    NASA Technical Reports Server (NTRS)

    Mohan, Ram V.; Tamma, Kumar K.

    1993-01-01

    An adaptive time stepping strategy for transient thermal analysis of engineering systems is described which computes the time step based on the local truncation error with a good global error control and obtains optimal time steps to be used during the analysis. Combined mesh partitionings involving FEM/FVM meshes based on physical situations to obtain numerically improved physical representations are also proposed. Numerical test cases are described and comparative pros and cons are identified for practical situations.

  8. Dynamics of the concentration of IAA and some of its conjugates during the induction of somatic embryogenesis in Coffea canephora

    PubMed Central

    Ayil-Gutiérrez, Benajmín; Galaz-Ávalos, Rosa María; Peña-Cabrera, Eduardo; Loyola-Vargas, Victor Manuel

    2013-01-01

    Most of the somatic embryogenesis (SE) process requires the presence, either before or during the embryogenic process, of at least one exogenous auxin. This exogenous auxin induces the presence of endogenous auxins, which appears to be essential for SE induction. We found that during the preincubation period of SE in Coffea canephora, there is an important increase in both free and conjugated indole-3-acetic acid (IAA), as well as indole-3-butyric acid. This increase is accompanied by an increase in the expression of YUCCA (CcYUC), TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 (CcTAA1), and GRETCHEN HAGEN 3 (GH3) genes. On the other hand, most of the IAA compounds decreased during the induction of SE. The results presented in this research suggest that a balance between free IAA and its amide conjugates is necessary to allow the expression of SE-related genes. PMID:24299659

  9. IAA Space Terminological Multilingual Data Bank Towards an On- Line Dictionary with Definitions in French and in English

    NASA Astrophysics Data System (ADS)

    Bensaid, R.

    2002-01-01

    It has been emphasized in previous papers that the bilingual "basic list" of the IAA multilingual terminological data bank (MTDB) needed improvement before beginning works on definitions. In this communication, in a first part, we report, on the works (corrections and additions) done to improve the scope of the "basic list" . These works have yet to be done by coordinators for the others twelve languages concerned by the IAA MTBD. In a second part, according to the decision of the IAA MTDB committee to complete the MTDB with definitions in French and in English, we describe the methodology adopted and the problems encountered to elaborate a mock-up of a space dictionary, including in a first step definitions in English and in French, of the English terms and expressions beginning by the letter "A" in the basic list.

  10. Polar Microalgae: New Approaches towards Understanding Adaptations to an Extreme and Changing Environment

    PubMed Central

    Lyon, Barbara R.; Mock, Thomas

    2014-01-01

    Polar Regions are unique and highly prolific ecosystems characterized by extreme environmental gradients. Photosynthetic autotrophs, the base of the food web, have had to adapt physiological mechanisms to maintain growth, reproduction and metabolic activity despite environmental conditions that would shut-down cellular processes in most organisms. High latitudes are characterized by temperatures below the freezing point, complete darkness in winter and continuous light and high UV in the summer. Additionally, sea-ice, an ecological niche exploited by microbes during the long winter seasons when the ocean and land freezes over, is characterized by large salinity fluctuations, limited gas exchange, and highly oxic conditions. The last decade has been an exciting period of insights into the molecular mechanisms behind adaptation of microalgae to the cryosphere facilitated by the advancement of new scientific tools, particularly “omics” techniques. We review recent insights derived from genomics, transcriptomics, and proteomics studies. Genes, proteins and pathways identified from these highly adaptable polar microbes have far-reaching biotechnological applications. Furthermore, they may provide insights into life outside this planet, as well as glimpses into the past. High latitude regions also have disproportionately large inputs into global biogeochemical cycles and are the region most sensitive to climate change. PMID:24833335

  11. Polar Microalgae: New Approaches towards Understanding Adaptations to an Extreme and Changing Environment.

    PubMed

    Lyon, Barbara R; Mock, Thomas

    2014-01-01

    Polar Regions are unique and highly prolific ecosystems characterized by extreme environmental gradients. Photosynthetic autotrophs, the base of the food web, have had to adapt physiological mechanisms to maintain growth, reproduction and metabolic activity despite environmental conditions that would shut-down cellular processes in most organisms. High latitudes are characterized by temperatures below the freezing point, complete darkness in winter and continuous light and high UV in the summer. Additionally, sea-ice, an ecological niche exploited by microbes during the long winter seasons when the ocean and land freezes over, is characterized by large salinity fluctuations, limited gas exchange, and highly oxic conditions. The last decade has been an exciting period of insights into the molecular mechanisms behind adaptation of microalgae to the cryosphere facilitated by the advancement of new scientific tools, particularly "omics" techniques. We review recent insights derived from genomics, transcriptomics, and proteomics studies. Genes, proteins and pathways identified from these highly adaptable polar microbes have far-reaching biotechnological applications. Furthermore, they may provide insights into life outside this planet, as well as glimpses into the past. High latitude regions also have disproportionately large inputs into global biogeochemical cycles and are the region most sensitive to climate change. PMID:24833335

  12. Local adaptive approach toward segmentation of microscopic images of activated sludge flocs

    NASA Astrophysics Data System (ADS)

    Khan, Muhammad Burhan; Nisar, Humaira; Ng, Choon Aun; Lo, Po Kim; Yap, Vooi Voon

    2015-11-01

    Activated sludge process is a widely used method to treat domestic and industrial effluents. The conditions of activated sludge wastewater treatment plant (AS-WWTP) are related to the morphological properties of flocs (microbial aggregates) and filaments, and are required to be monitored for normal operation of the plant. Image processing and analysis is a potential time-efficient monitoring tool for AS-WWTPs. Local adaptive segmentation algorithms are proposed for bright-field microscopic images of activated sludge flocs. Two basic modules are suggested for Otsu thresholding-based local adaptive algorithms with irregular illumination compensation. The performance of the algorithms has been compared with state-of-the-art local adaptive algorithms of Sauvola, Bradley, Feng, and c-mean. The comparisons are done using a number of region- and nonregion-based metrics at different microscopic magnifications and quantification of flocs. The performance metrics show that the proposed algorithms performed better and, in some cases, were comparable to the state-of the-art algorithms. The performance metrics were also assessed subjectively for their suitability for segmentations of activated sludge images. The region-based metrics such as false negative ratio, sensitivity, and negative predictive value gave inconsistent results as compared to other segmentation assessment metrics.

  13. U.S. natural resources and climate change: concepts and approaches for management adaptation.

    PubMed

    West, Jordan M; Julius, Susan H; Kareiva, Peter; Enquist, Carolyn; Lawler, Joshua J; Petersen, Brian; Johnson, Ayana E; Shaw, M Rebecca

    2009-12-01

    Public lands and waters in the United States traditionally have been managed using frameworks and objectives that were established under an implicit assumption of stable climatic conditions. However, projected climatic changes render this assumption invalid. Here, we summarize general principles for management adaptations that have emerged from a major literature review. These general principles cover many topics including: (1) how to assess climate impacts to ecosystem processes that are key to management goals; (2) using management practices to support ecosystem resilience; (3) converting barriers that may inhibit management responses into opportunities for successful implementation; and (4) promoting flexible decision making that takes into account challenges of scale and thresholds. To date, the literature on management adaptations to climate change has mostly focused on strategies for bolstering the resilience of ecosystems to persist in their current states. Yet in the longer term, it is anticipated that climate change will push certain ecosystems and species beyond their capacity to recover. When managing to support resilience becomes infeasible, adaptation may require more than simply changing management practices--it may require changing management goals and managing transitions to new ecosystem states. After transitions have occurred, management will again support resilience--this time for a new ecosystem state. Thus, successful management of natural resources in the context of climate change will require recognition on the part of managers and decisions makers of the need to cycle between "managing for resilience" and "managing for change."

  14. Integrated approach for studying adaptation mechanisms in the human somatosensory cortical network.

    PubMed

    Venkatesan, Lalit; Barlow, Steven M; Popescu, Mihai; Popescu, Anda

    2014-11-01

    Magnetoencephalography and independent component analysis (ICA) was utilized to study and characterize neural adaptation in the somatosensory cortical network. Repetitive punctate tactile stimuli were applied unilaterally to the dominant hand and face using a custom-built pneumatic stimulator called the TAC-Cell. ICA-based source estimation from the evoked neuromagnetic responses indicated cortical activity in the contralateral primary somatosensory cortex (SI) for face stimulation, while hand stimulation resulted in robust contralateral SI and posterior parietal cortex (PPC) activation. Activity was also observed in the secondary somatosensory cortical area (SII) with reduced amplitude and higher variability across subjects. There was a significant difference in adaptation rate between SI and higher-order somatosensory cortices for hand stimulation. Adaptation was significantly dependent on stimulus frequency and pulse index within the stimulus train for both hand and face stimulation. The peak latency of the activity was significantly dependent on stimulation site (hand vs. face) and cortical area (SI vs. PPC). The difference in the peak latency of activity in SI and PPC is presumed to reflect a hierarchical serial-processing mechanism in the somatosensory cortex.

  15. A systematic approach to cross-cultural adaptation of survey tools

    PubMed Central

    Costa, Filipa A.; Duggan, Catherine; Bates, Ian

    Background Involving patients in health care is increasingly acknowledged as the best way to empower patients to manage their illness. Whilst the involvement of patients is laudable and widely recognised, how much they want to be involved needs to be ascertained. Research has shown that inappropriate provision of information to patients can increase their anxieties towards illness and alter perceptions of medicines’ usefulness, consequently impacting on medicines’ taking behaviour. Tools have been validated in the UK to identify information desires, perceived usefulness of medicines and anxiety felt about illness. There is a need to adapt validated tools for use in other settings and countries. This paper is the first of a series describing the processes involved in the adaptation and validation of these. Aim to review and adapt the processes established to translate and back translate scales and tools in practice. Methods The survey tool was translated and back- translated according to published guidelines, subsequently tested in a sample of medical patients and further refined by seeking health care professionals’ perceptions and input from lay people. Results Data demonstrates the importance of including various perspectives in this process, through which sequential modifications were made to the original scales. Issues relating to religious beliefs, educational and health literacy differences between countries highlight the relevance of taking cultural values into account. Some led to significant modifications, discussed in this first paper, and tested for validity and reliability in a second paper. PMID:25214927

  16. A morphological adaptation approach to path planning inspired by slime mould

    NASA Astrophysics Data System (ADS)

    Jones, Jeff

    2015-04-01

    Path planning is a classic problem in computer science and robotics which has recently been implemented in unconventional computing substrates such as chemical reaction-diffusion computers. These novel computing schemes utilise the parallel spatial propagation of information and often use a two-stage method involving diffusive propagation to discover all paths and a second stage to highlight or visualise the path between two particular points in the arena. The true slime mould Physarum polycephalum is known to construct efficient transport networks between nutrients in its environment. These networks are continuously remodelled as the organism adapts its body plan to changing spatial stimuli. It can be guided towards attractant stimuli (nutrients, warm regions) and it avoids locations containing hazardous stimuli (light irradiation, repellents, or regions occupied by predatory threats). Using a particle model of slime mould we demonstrate scoping experiments which explore how path planning may be performed by morphological adaptation. We initially demonstrate simple path planning by a shrinking blob of virtual plasmodium between two attractant sources within a polygonal arena. We examine the case where multiple paths are required and the subsequent selection of a single path from multiple options. Collision-free paths are implemented via repulsion from the borders of the arena. Finally, obstacle avoidance is implemented by repulsion from obstacles as they are uncovered by the shrinking blob. These examples show proof-of-concept results of path planning by morphological adaptation which complement existing research on path planning in novel computing substrates.

  17. Testing Local Adaptation in a Natural Great Tit-Malaria System: An Experimental Approach

    PubMed Central

    Jenkins, Tania; Delhaye, Jessica; Christe, Philippe

    2015-01-01

    Finding out whether Plasmodium spp. are coevolving with their vertebrate hosts is of both theoretical and applied interest and can influence our understanding of the effects and dynamics of malaria infection. In this study, we tested for local adaptation as a signature of coevolution between malaria blood parasites, Plasmodium spp. and its host, the great tit, Parus major. We conducted a reciprocal transplant experiment of birds in the field, where we exposed birds from two populations to Plasmodium parasites. This experimental set-up also provided a unique opportunity to study the natural history of malaria infection in the wild and to assess the effects of primary malaria infection on juvenile birds. We present three main findings: i) there was no support for local adaptation; ii) there was a male-biased infection rate; iii) infection occurred towards the end of the summer and differed between sites. There were also site-specific effects of malaria infection on the hosts. Taken together, we present one of the few experimental studies of parasite-host local adaptation in a natural malaria system, and our results shed light on the effects of avian malaria infection in the wild. PMID:26555892

  18. A Framework Approach to Evaluate Cross-Cultural Adaptation of Public Engagement Strategies for Radioactive Waste Management - 13430

    SciTech Connect

    Hermann, Laura

    2013-07-01

    The complex interplay of politics, economics and culture undermines attempts to define universal best practices for public engagement in the management of nuclear materials. In the international context, communicators must rely on careful adaptation and creative execution to make standard communication techniques succeed in their local communities. Nuclear professionals need an approach to assess and adapt culturally specific public engagement strategies to meet the demands of their particular political, economic and social structures. Using participant interviews and public sources, the Potomac Communications Group reviewed country-specific examples of nuclear-related communication efforts to provide insight into a proposed approach. The review considered a spectrum of cultural dimensions related to diversity, authority, conformity, proximity and time. Comparisons help to identify cross-cultural influences of various public engagement tactics and to inform a framework for communicators. While not prescriptive in its application, the framework offers a way for communicators to assess the salience of outreach tactics in specific situations. The approach can guide communicators to evaluate and tailor engagement strategies to achieve localized public outreach goals. (authors)

  19. Using graphical adaptive lasso approach to construct transcription factor and microRNA's combinatorial regulatory network in breast cancer.

    PubMed

    Su, Naifang; Dai, Ding; Deng, Chao; Qian, Minping; Deng, Minghua

    2014-06-01

    Discovering the regulation of cancer-related gene is of great importance in cancer biology. Transcription factors and microRNAs are two kinds of crucial regulators in gene expression, and they compose a combinatorial regulatory network with their target genes. Revealing the structure of this network could improve the authors' understanding of gene regulation, and further explore the molecular pathway in cancer. In this article, the authors propose a novel approach graphical adaptive lasso (GALASSO) to construct the regulatory network in breast cancer. GALASSO use a Gaussian graphical model with adaptive lasso penalties to integrate the sequence information as well as gene expression profiles. The simulation study and the experimental profiles verify the accuracy of the authors' approach. The authors further reveal the structure of the regulatory network, and explore the role of feedforward loops in gene regulation. In addition, the authors discuss the combinatorial regulatory effect between transcription factors and microRNAs, and select miR-155 for detailed analysis of microRNA's role in cancer. The proposed GALASSO approach is an efficient method to construct the combinatorial regulatory network. It also provides a new way to integrate different data sources and could find more applications in meta-analysis problem.

  20. Feasibility of Automated Adaptive GCA (Ground Controlled Approach) Controller Training System.

    ERIC Educational Resources Information Center

    Feuge, Robert L.; And Others

    An analysis of the conceptual feasibility of using automatic speech recognition and understanding technology in the design of an advanced training system was conducted. The analysis specifically explored application to Ground Controlled Approach (GCA) controller training. A systems engineering approach was followed to determine the feasibility of…

  1. The development and demonstration of hybrid programmable attitude control electronics. [with adaptable analog/digital design approach

    NASA Technical Reports Server (NTRS)

    Smith, L. S.; Kopf, E. H., Jr.

    1974-01-01

    HYPACE provides an adaptable, analog/digital design approach that permits preflight and in-flight accommodation of mission changes, component performance variations, spacecraft changes, etc., through programing. This enabled broad multimission flexibility of application in a cost-effective manner. The HYPACE design, which was demonstrated in breadboard form on a single-axis gas-bearing spacecraft simulation, uses a single control channel to perform the attitude control functions sequentially, thus significantly reducing the number of component parts over hard-wired designs. The success of this effort resulted in the concept being selected for the Mariner/Jupiter/Saturn 1977 spacecraft application.

  2. Ambient illumination revisited: A new adaptation-based approach for optimizing medical imaging reading environments

    SciTech Connect

    Chawla, Amarpreet S.; Samei, Ehsan

    2007-01-15

    Ambient lighting in soft-copy reading rooms is currently kept at low values to preserve contrast rendition in the dark regions of a medical image. Low illuminance levels, however, create inadequate viewing conditions and may also cause eye strain. This eye strain may be potentially attributed to notable variations in the luminance adaptation state of the reader's eyes when moving the gaze intermittently between the brighter display and darker surrounding surfaces. This paper presents a methodology to minimize this variation and optimize the lighting conditions of reading rooms by exploiting the properties of liquid crystal displays (LCDs) with low diffuse reflection coefficients and high luminance ratio. First, a computational model was developed to determine a global luminance adaptation value, L{sub adp}, when viewing a medical image on display. The model is based on the diameter of the pupil size, which depends on the luminance of the observed object. Second, this value was compared with the luminance reflected off surrounding surfaces, L{sub s}, under various conditions of room illuminance, E, different values of diffuse reflection coefficients of surrounding surfaces, R{sub s}, and calibration settings of a typical LCD. The results suggest that for typical luminance settings of current LCDs, it is possible to raise ambient illumination to minimize differences in eye adaptation, potentially reducing visual fatigue while also complying with the TG18 specifications for controlled contrast rendition. Specifically, room illumination in the 75-150 lux range and surface diffuse reflection coefficients in the practical range of 0.13-0.22 sr{sup -1} provide an ideal setup for typical LCDs. Future LCDs with lower diffuse reflectivity and with higher inherent luminance ratios can provide further improvement of ergonomic viewing conditions in reading rooms.

  3. Biostatistical methods for demonstrating efficacy in the regulatory setting. An epistemological approach to adaptive designs.

    PubMed

    Koch, A

    2005-05-01

    Adaptive designs are one of the most promising developments in statistics with applications to clinical trials. Obviously the knowledge at the beginning of a clinical trial will always be limited. In consequence it may be considered necessary that the knowledge from accumulating information should be used to optimize the design of the trial. This paper discusses conditions under which this may be possible in phase III clinical trials where the principle aim is confirmation of hypotheses that have been developed in earlier stages of drug development.

  4. An adaptive Newton-method based on a dynamical systems approach

    NASA Astrophysics Data System (ADS)

    Amrein, Mario; Wihler, Thomas P.

    2014-09-01

    The traditional Newton method for solving nonlinear operator equations in Banach spaces is discussed within the context of the continuous Newton method. This setting makes it possible to interpret the Newton method as a discrete dynamical system and thereby to cast it in the framework of an adaptive step size control procedure. In so doing, our goal is to reduce the chaotic behavior of the original method without losing its quadratic convergence property close to the roots. The performance of the modified scheme is illustrated with various examples from algebraic and differential equations.

  5. [New methodological approaches in assessing adaptive body reactions in the system of flight medicine expertise].

    PubMed

    Karlov, V N; Balandina, T N

    1995-01-01

    The "cost" of adjustable systemic and cellular reactions in the human body in extreme environments have been assessed from the standpoint of their potentialities for upgrading special methods of evaluating and predicting functional status practiced in flight certification examination. As was stated, the functional reserves of blood circulation should be assessed by chronotropic activity of cardiac regulation in response to hypoxic exposure. The adequacy of adaptive processes on the cellular level can be drawn from the dynamics of malon-dialdehide (the by-product of lipid peroxidation) and plasma monoaminoxidase. The biochemical investigations of peripheral blood and saliva also show promise.

  6. Improvements on adaptive optics control approaches: experimental tests of wavefront correction forecasting

    NASA Astrophysics Data System (ADS)

    Del Moro, Dario; Piazzesi, Roberto; Stangalini, Marco; Giovannelli, Luca; Berrilli, Francesco

    2015-01-01

    The FORS (closed loop forecasting system) control algorithm has been already successfully applied to improve the efficiency of a simulated adaptive optics (AO) system. To test its performance in real conditions, we implemented this algorithm in a hardware AO demonstrator, introducing controlled aberrations into the system. We present here the results of introducing into the system both a simple periodic defocus aberration and a real open loop defocus time sequence acquired at the vacuum tower telescope solar telescope. In both cases, FORS yields a significant performance increase, improving the stability of the system in closed-loop conditions and decreasing the amplitude of the residual uncorrected wavefront aberrations.

  7. The FIGS (focused identification of germplasm strategy) approach identifies traits related to drought adaptation in Vicia faba genetic resources.

    PubMed

    Khazaei, Hamid; Street, Kenneth; Bari, Abdallah; Mackay, Michael; Stoddard, Frederick L

    2013-01-01

    Efficient methods to explore plant agro-biodiversity for climate change adaptive traits are urgently required. The focused identification of germplasm strategy (FIGS) is one such approach. FIGS works on the premise that germplasm is likely to reflect the selection pressures of the environment in which it developed. Environmental parameters describing plant germplasm collection sites are used as selection criteria to improve the probability of uncovering useful variation. This study was designed to test the effectiveness of FIGS to search a large faba bean (Vicia faba L.) collection for traits related to drought adaptation. Two sets of faba bean accessions were created, one from moisture-limited environments, and the other from wetter sites. The two sets were grown under well watered conditions and leaf morpho-physiological traits related to plant water use were measured. Machine-learning algorithms split the accessions into two groups based on the evaluation data and the groups created by this process were compared to the original climate-based FIGS sets. The sets defined by trait data were in almost perfect agreement to the FIGS sets, demonstrating that ecotypic differentiation driven by moisture availability has occurred within the faba bean genepool. Leaflet and canopy temperature as well as relative water content contributed more than other traits to the discrimination between sets, indicating that their utility as drought-tolerance selection criteria for faba bean germplasm. This study supports the assertion that FIGS could be an effective tool to enhance the discovery of new genes for abiotic stress adaptation.

  8. EEG/ERP adaptive noise canceller design with controlled search space (CSS) approach in cuckoo and other optimization algorithms.

    PubMed

    Ahirwal, M K; Kumar, Anil; Singh, G K

    2013-01-01

    This paper explores the migration of adaptive filtering with swarm intelligence/evolutionary techniques employed in the field of electroencephalogram/event-related potential noise cancellation or extraction. A new approach is proposed in the form of controlled search space to stabilize the randomness of swarm intelligence techniques especially for the EEG signal. Swarm-based algorithms such as Particles Swarm Optimization, Artificial Bee Colony, and Cuckoo Optimization Algorithm with their variants are implemented to design optimized adaptive noise canceler. The proposed controlled search space technique is tested on each of the swarm intelligence techniques and is found to be more accurate and powerful. Adaptive noise canceler with traditional algorithms such as least-mean-square, normalized least-mean-square, and recursive least-mean-square algorithms are also implemented to compare the results. ERP signals such as simulated visual evoked potential, real visual evoked potential, and real sensorimotor evoked potential are used, due to their physiological importance in various EEG studies. Average computational time and shape measures of evolutionary techniques are observed 8.21E-01 sec and 1.73E-01, respectively. Though, traditional algorithms take negligible time consumption, but are unable to offer good shape preservation of ERP, noticed as average computational time and shape measure difference, 1.41E-02 sec and 2.60E+00, respectively.

  9. Finite time-Lyapunov based approach for robust adaptive control of wind-induced oscillations in power transmission lines

    NASA Astrophysics Data System (ADS)

    Ghabraei, Soheil; Moradi, Hamed; Vossoughi, Gholamreza

    2016-06-01

    Large amplitude oscillation of the power transmission lines, which is also known as galloping phenomenon, has hazardous consequences such as short circuiting and failure of transmission line. In this article, to suppress the undesirable vibrations of the transmission lines, first the governing equations of transmission line are derived via mode summation technique. Then, due to the occurrence of large amplitude vibrations, nonlinear quadratic and cubic terms are included in the derived linear equations. To suppress the vibrations, arbitrary number of the piezoelectric actuators is assumed to exert the actuation forces. Afterwards, a Lyapunov based approach is proposed for the robust adaptive suppression of the undesirable vibrations in the finite time. To compensate the supposed parametric uncertainties with unknown bands, proper adaption laws are introduced. To avoid the vibration devastating consequences as quickly as possible, appropriate control laws are designed. The vibration suppression in the finite time with supposed adaption and control laws is mathematically proved via Lyapunov finite time stability theory. Finally, to illustrate and validate the efficiency and robustness of the proposed finite time control scheme, a parametric case study with three piezoelectric actuators is performed. It is observed that the proposed active control strategy is more efficient and robust than the passive control methods.

  10. Introduction to the symposium: responses of organisms to climate change: a synthetic approach to the role of thermal adaptation.

    PubMed

    Sears, Michael W; Angilletta, Michael J

    2011-11-01

    On a global scale, changing climates are affecting ecological systems across multiple levels of biological organization. Moreover, climates are changing at rates unprecedented in recent geological history. Thus, one of the most pressing concerns of the modern era is to understand the biological responses to climate such that society can both adapt and implement measures that attempt to offset the negative impacts of a rapidly changing climate. One crucial question, to understand organismal responses to climate, is whether the ability of organisms to adapt can keep pace with quickly changing environments. To address this question, a syntheses of knowledge from a broad set of biological disciplines will be needed that integrates information from the fields of ecology, behavior, physiology, genetics, and evolution. This symposium assembled a diverse group of scientists from these subdisciplines to present their perspectives regarding the ability of organisms to adapt to changing climates. Specifically, the goals of this symposia were to (1) highlight what each discipline brings to a discussion of organismal responses to climate, (2) to initiate and foster a discussion to break barriers in the transfer of knowledge across disciplines, and (3) to synthesize an approach to address ongoing issues concerning biological responses to climate.

  11. An auto-adaptive optimization approach for targeting nonpoint source pollution control practices

    PubMed Central

    Chen, Lei; Wei, Guoyuan; Shen, Zhenyao

    2015-01-01

    To solve computationally intensive and technically complex control of nonpoint source pollution, the traditional genetic algorithm was modified into an auto-adaptive pattern, and a new framework was proposed by integrating this new algorithm with a watershed model and an economic module. Although conceptually simple and comprehensive, the proposed algorithm would search automatically for those Pareto-optimality solutions without a complex calibration of optimization parameters. The model was applied in a case study in a typical watershed of the Three Gorges Reservoir area, China. The results indicated that the evolutionary process of optimization was improved due to the incorporation of auto-adaptive parameters. In addition, the proposed algorithm outperformed the state-of-the-art existing algorithms in terms of convergence ability and computational efficiency. At the same cost level, solutions with greater pollutant reductions could be identified. From a scientific viewpoint, the proposed algorithm could be extended to other watersheds to provide cost-effective configurations of BMPs. PMID:26487474

  12. An approach for assessing human health vulnerability and public health interventions to adapt to climate change.

    PubMed

    Ebi, Kristie L; Kovats, R Sari; Menne, Bettina

    2006-12-01

    Assessments of the potential human health impacts of climate change are needed to inform the development of adaptation strategies, policies, and measures to lessen projected adverse impacts. We developed methods for country-level assessments to help policy makers make evidence-based decisions to increase resilience to current and future climates, and to provide information for national communications to the United Nations Framework Convention on Climate Change. The steps in an assessment should include the following: a) determine the scope of the assessment; b) describe the current distribution and burden of climate-sensitive health determinants and outcomes; c) identify and describe current strategies, policies, and measures designed to reduce the burden of climate-sensitive health determinants and outcomes; d) review the health implications of the potential impacts of climate variability and change in other sectors; e) estimate the future potential health impacts using scenarios of future changes in climate, socioeconomic, and other factors; f) synthesize the results; and g) identify additional adaptation policies and measures to reduce potential negative health impacts. Key issues for ensuring that an assessment is informative, timely, and useful include stakeholder involvement, an adequate management structure, and a communication strategy.

  13. Adaptive Sampling approach to environmental site characterization at Joliet Army Ammunition Plant: Phase 2 demonstration

    SciTech Connect

    Bujewski, G.E.; Johnson, R.L.

    1996-04-01

    Adaptive sampling programs provide real opportunities to save considerable time and money when characterizing hazardous waste sites. This Strategic Environmental Research and Development Program (SERDP) project demonstrated two decision-support technologies, SitePlanner{trademark} and Plume{trademark}, that can facilitate the design and deployment of an adaptive sampling program. A demonstration took place at Joliet Army Ammunition Plant (JAAP), and was unique in that it was tightly coupled with ongoing Army characterization work at the facility, with close scrutiny by both state and federal regulators. The demonstration was conducted in partnership with the Army Environmental Center`s (AEC) Installation Restoration Program and AEC`s Technology Development Program. AEC supported researchers from Tufts University who demonstrated innovative field analytical techniques for the analysis of TNT and DNT. SitePlanner{trademark} is an object-oriented database specifically designed for site characterization that provides an effective way to compile, integrate, manage and display site characterization data as it is being generated. Plume{trademark} uses a combination of Bayesian analysis and geostatistics to provide technical staff with the ability to quantitatively merge soft and hard information for an estimate of the extent of contamination. Plume{trademark} provides an estimate of contamination extent, measures the uncertainty associated with the estimate, determines the value of additional sampling, and locates additional samples so that their value is maximized.

  14. Adaptation to changing water resource availability in Northern India with respect to Himalayan Glacier retreat and changing monsoons using participatory approaches.

    PubMed

    Bhadwal, Suruchi; Groot, Annemarie; Balakrishnan, Sneha; Nair, Sreeja; Ghosh, Sambita; Lingaraj, G J; van Scheltinga, Catharien Terwisscha; Bhave, Ajay; Siderius, Christian

    2013-12-01

    Changes in rainfall patterns and temperatures are likely to affect water resources in India. Also, changes in the extreme events will have direct implications on life and property. Adapting to the adverse effects of climate change becomes critical to avoid huge material and immaterial damages. This paper discusses the use of a multi-level and participatory approach to develop adaptation options to deal with climate related risks in a manner that contributes to stakeholder engagement, understanding of the risks, identification of the adaptation responses as well as its prioritization for risk reduction. It highlights the importance of involving stakeholders from multiple levels as each level corresponds with different priorities in adaptation options.

  15. Health risk in the context of climate change and adaptation - Concept and mapping as an integrated approach

    NASA Astrophysics Data System (ADS)

    Kienberger, S.; Notenbaert, A.; Zeil, P.; Bett, B.; Hagenlocher, M.; Omolo, A.

    2012-04-01

    Climate change has been stated as being one of the greatest challenges to global health in the current century. Climate change impacts on human health and the socio-economic and related poverty consequences are however still poorly understood. While epidemiological issues are strongly coupled with environmental and climatic parameters, the social and economic circumstances of populations might be of equal or even greater importance when trying to identify vulnerable populations and design appropriate and well-targeted adaptation measures. The inter-linkage between climate change, human health risk and socio-economic impacts remains an important - but largely outstanding - research field. We present an overview on how risk is traditionally being conceptualised in the human health domain and reflect critically on integrated approaches as being currently used in the climate change context. The presentation will also review existing approaches, and how they can be integrated towards adaptation tools. Following this review, an integrated risk concept is being presented, which has been currently adapted under the EC FP7 research project (HEALTHY FUTURES; http://www.healthyfutures.eu/). In this approach, health risk is not only defined through the disease itself (as hazard) but also by the inherent vulnerability of the system, population or region under study. It is in fact the interaction of environment and society that leads to the development of diseases and the subsequent risk of being negatively affected by it. In this conceptual framework vulnerability is being attributed to domains of lack of resilience as well as underlying preconditions determining susceptibilities. To fulfil a holistic picture vulnerability can be associated to social, economic, environmental, institutional, cultural and physical dimensions. The proposed framework also establishes the important nexus to adaptation and how different measures can be related to avoid disease outbreaks, reduce

  16. Effects of Kinetin, IAA, and Gibberellin on Ethylene Production, and Their Interactions in Growth of Seedlings.

    PubMed

    Fuchs, Y; Lieberman, M

    1968-12-01

    Kinetin in concentrations of 10(-8) to 10(-4)m, stimulated ethylene production in 3 and 4-day old etiolated seedlings of Alaska pea (Pisum sativum L. var. Alaska). Seedlings of other species responded similarly. The response to kinetin depended on the age of the seedlings.Kinetin alone did not influence ethylene production in 6-day old stem sections, but it greatly increased the enhancing effect of IAA.Gibberellic acid had no effect on ethylene production by pea seedlings during the first 6 days of growth. Ethylene and gibberellic acid are antagonistic in their effects on growth of the seedlings; ethylene interfered severely with the action of gibberellic acid but did not completely suppress it.The inhibitors cycloheximide, cupferron, and N-ethylmaleimide, caused considerable inhibition of kinetin-induced ethylene production but were much less effective in the endogenous ethylene-forming system. PMID:16657004

  17. Transport of stele-associated IAA in gravistimulated roots of maize

    SciTech Connect

    Stinemetz, C.L.; Evans, M.L. )

    1989-04-01

    We tested the redistribution of label from a pulse of {sup 3}H IAA applied to the cut surface of 5 mm apical root segments. We determined the amount of label in the stele, meristematic region (MR), root cap, and cortical tissue on the lower and upper sides of gravistimulated vs control roots. Label entered the stele and moved into the MR prior to accumulating in the elongation zone (EZ). Little label moved into the cap. Gravistimulation did not increase the amount of label moving from the stele, but it increased the amount of label accumulating on the lower side of the EZ. Removal of the cap immediately following gravistimulation rendered the roots insensitive to gravity and prevented gravi-induced asymmetric redistribution of label. The results suggest that a signal originating in the root cap directs auxin redistribution in tissue behind the cap.

  18. Approach to prevent locking in a spring-damper system by adaptive load redistribution with auxiliary kinematic guidance elements

    NASA Astrophysics Data System (ADS)

    Gehb, Christopher M.; Platz, Roland; Melz, Tobias

    2015-04-01

    In many applications, kinematic structures are used to enable and disable degrees of freedom. The relative movement between a wheel and the body of a car or a landing gear and an aircraft fuselage are examples for a defined movement. In most cases, a spring-damper system determines the kinetic properties of the movement. However, unexpected high load peaks may lead to maximum displacements and maybe to locking. Thus, a hard clash between two rigid components may occur, causing acceleration peaks. This may have harmful effects for the whole system. For example a hard landing of an aircraft can result in locking the landing gear and thus damage the entire aircraft. In this paper, the potential of adaptive auxiliary kinematic guidance elements in a spring-damper system to prevent locking is investigated numerically. The aim is to provide additional forces in the auxiliary kinematic guidance elements in case of overloading the spring-damper system and thus to absorb some of the impact energy. To estimate the potential of the load redistribution in the spring-damper system, a numerical model of a two-mass oscillator is used, similar to a quarter-car-model. In numerical calculations, the reduction of the acceleration peaks of the masses with the adaptive approach is compared to the Acceleration peaks without the approach, or, respectively, when locking is not prevented. In addition, the required force of the adaptive auxiliary kinematic guidance elements is calculated as a function of the masses of the system and the drop height, or, respectively, the impact energy.

  19. The PICS Climate Insights 101 Courses: A Visual Approach to Learning About Climate Science, Mitigation and Adaptation

    NASA Astrophysics Data System (ADS)

    Pedersen, T. F.; Zwiers, F. W.; Breen, C.; Murdock, T. Q.

    2014-12-01

    The Pacific Institute for Climate Solutions (PICS) has now made available online three free, peer-reviewed, unique animated short courses in a series entitled "Climate Insights 101" that respectively address basic climate science, carbon-emissions mitigation approaches and opportunities, and adaptation. The courses are suitable for students of all ages, and use professionally narrated animations designed to hold a viewer's attention. Multiple issues are covered, including complex concerns like the construction of general circulation models, carbon pricing schemes in various countries, and adaptation approaches in the face of extreme weather events. Clips will be shown in the presentation. The first course (Climate Science Basics) has now been seen by over two hundred thousand individuals in over 80 countries, despite being offered in English only. Each course takes about two hours to work through, and in recognizing that that duration might pose an attention barrier to some students, PICS selected a number of short clips from the climate-science course and posted them as independent snippets on YouTube. A companion series of YouTube videos entitled, "Clear The Air", was created to confront the major global-warming denier myths. But a major challenge remains: despite numerous efforts to promote the availability of the free courses and the shorter YouTube pieces, they have yet to become widely known. Strategies to overcome that constraint will be discussed.

  20. An adaptive approach to centerline extraction for CT colonography using MAP-EM segmentation and distance field

    NASA Astrophysics Data System (ADS)

    Peng, Hao; Li, Lihong C.; Wang, Huafeng; Han, Hao; Pickhardt, Perry J.; Liang, Zhengrong

    2014-03-01

    In this paper, we present an adaptive approach for fully automatic centerline extraction and small intestine removal based on partial volume (PV) image segmentation and distance field modeling. Computed tomographic colonography (CTC) volume image is first segmented for the colon wall mucosa layer, which represents the PV effect around the colon wall. Then centerline extraction is performed in the presence of colon collapse and small intestine touch by the use of distance field within the segmented PV mucosa layer, where centerline breakings due to collapse are recovered and centerline branches due to small intestine tough are removed. Experimental results from 24 patient CTC scans with small intestine touch rendered 100% removal of the touch, while only 16 out of the 24 could be done by the well-known isolated component method. Our voxel-by-voxel marking strategy in the automated procedure preserves the topology and validity of the colon structure. The marked inner and outer boundaries on cleansed colon are very close to those labeled by the experts. Experimental results demonstrated the robustness and efficiency of the presented adaptive approach for CTC utility.

  1. An Adaptive CBPR Approach to Create Weight Management Materials for a School-Based Health Center Intervention

    PubMed Central

    Sussman, Andrew L.; Montoya, Carolyn; Davis, Sally; Wallerstein, Nina; Kong, Alberta S.

    2013-01-01

    Purpose. From our previous clinical work with overweight/obese youth, we identified the need for research to create an effective weight management intervention to address the growing prevalence of adolescent metabolic syndrome. Formative assessment through an adaptive community-based participatory research (CBPR) approach was conducted toward the development of a nutritional and physical activity (DVD) and clinician toolkit for a school-based health center (SBHC) weight management intervention. Methods. We first conducted parent and adolescent interviews on views and experiences about obesity while convening a community advisory council (CAC) recruited from two participating urban New Mexico high schools. Thematic findings from the interviews were analyzed with the CAC to develop culturally and developmentally appropriate intervention materials. Results. Themes from the parent and adolescent interviews included general barriers/challenges, factors influencing motivation, and change facilitators. The CAC and university-based research team reached consensus on the final content of nutrition and physical activity topics to produce a DVD and clinician toolkit through six monthly sessions. These materials used in the SBHC intervention resulted in a greater reduction of body mass index when compared to adolescents receiving standard care. Conclusions. Formative assessment using an adaptive CBPR approach resulted in the creation of culturally and age appropriate weight reduction materials that were acceptable to study participants. This trial is registered with ClinicalTrials.gov NCT00841334. PMID:23984053

  2. A Predictive Approach to Nonparametric Inference for Adaptive Sequential Sampling of Psychophysical Experiments

    PubMed Central

    Benner, Philipp; Elze, Tobias

    2012-01-01

    We present a predictive account on adaptive sequential sampling of stimulus-response relations in psychophysical experiments. Our discussion applies to experimental situations with ordinal stimuli when there is only weak structural knowledge available such that parametric modeling is no option. By introducing a certain form of partial exchangeability, we successively develop a hierarchical Bayesian model based on a mixture of Pólya urn processes. Suitable utility measures permit us to optimize the overall experimental sampling process. We provide several measures that are either based on simple count statistics or more elaborate information theoretic quantities. The actual computation of information theoretic utilities often turns out to be infeasible. This is not the case with our sampling method, which relies on an efficient algorithm to compute exact solutions of our posterior predictions and utility measures. Finally, we demonstrate the advantages of our framework on a hypothetical sampling problem. PMID:22822269

  3. A Multiagent Approach to Adaptive Continuous Analysis of Streaming Data in Complex Uncertain Environments

    NASA Astrophysics Data System (ADS)

    Kiselev, Igor; Alhajj, Reda

    The data mining task of online unsupervised learning of streaming data continually arriving at the system in complex dynamic environments under conditions of uncertainty is an NP-hard optimization problem for general metric spaces and is computationally intractable for real-world problems of practical interest. The primary contribution of this work is a multi-agent method for continuous agglomerative hierarchical clustering of streaming data, and a knowledge-based selforganizing competitive multi-agent system for implementing it. The reported experimental results demonstrate the applicability and efficiency of the implemented adaptive multi-agent learning system for continuous online clustering of both synthetic datasets and datasets from the following real-world domains: the RoboCup Soccer competition, and gene expression datasets from a bioinformatics test bed.

  4. Genetic algorithm approach for adaptive power and subcarrier allocation in multi-user OFDM systems

    NASA Astrophysics Data System (ADS)

    Reddy, Y. B.; Naraghi-Pour, Mort

    2007-04-01

    In this paper, a novel genetic algorithm application is proposed for adaptive power and subcarrier allocation in multi-user Orthogonal Frequency Division Multiplexing (OFDM) systems. To test the application, a simple genetic algorithm was implemented in MATLAB language. With the goal of minimizing the overall transmit power while ensuring the fulfillment of each user's rate and bit error rate (BER) requirements, the proposed algorithm acquires the needed allocation through genetic search. The simulations were tested for BER 0.1 to 0.00001, data rate of 256 bit per OFDM block and chromosome length of 128. The results show that genetic algorithm outperforms the results in [3] in subcarrier allocation. The convergence of GA model with 8 users and 128 subcarriers performs better in power requirement compared to that in [4] but converges more slowly.

  5. Peers as resources for learning: a situated learning approach to adapted physical activity in rehabilitation.

    PubMed

    Standal, Øyvind F; Jespersen, Ejgil

    2008-07-01

    The purpose of this study was to investigate the learning that takes place when people with disabilities interact in a rehabilitation context. Data were generated through in-depth interviews and close observations in a 2 (1/2) week-long rehabilitation program, where the participants learned both wheelchair skills and adapted physical activities. The findings from the qualitative data analysis are discussed in the context of situated learning (Lave & Wenger, 1991; Wenger, 1998). The results indicate that peer learning extends beyond skills and techniques, to include ways for the participants to make sense of their situations as wheelchair users. Also, it was found that the community of practice established between the participants represented a critical corrective to instructions provided by rehabilitation professionals.

  6. Application of ameliorative and adaptive approaches to revegetation of historic high altitude mining waste

    SciTech Connect

    Bellitto, M.W.; Williams, H.T.; Ward, J.N.

    1999-07-01

    High altitude, historic, gold and silver tailings deposits, which included a more recent cyanide heap leach operation, were decommissioned, detoxified, re-contoured and revegetated. Detoxification of the heap included rinsing with hydrogen peroxide, lime and ferric chloride, followed by evaporation and land application of remaining solution. Grading included the removal of solution ponds, construction of a geosynthetic/clay lined pond, heap removal and site drainage development. Ameliorative and adaptive revegetation methodologies were utilized. Revegetation was complicated by limited access, lack of topsoil, low pH and evaluated metals concentrations in the tailings, and a harsh climate. Water quality sampling results for the first year following revegetation, indicate reclamation activities have contributed to a decrease in metals and sediment loading to surface waters downgradient of the site. Procedures, methodologies and results, following the first year of vegetation growth, are provided.

  7. An adaptive governance approach to disaster-related behavioural health services.

    PubMed

    Andrew, Simon A; Kendra, James M

    2012-07-01

    This paper explores the provision of disaster-related behavioural and mental health (DBH) services as a problem of institutional collective action in the United States. This study reviews the challenges that providers have in surmounting multi-organizational disconnects, unstable professional legitimacy, ambiguous information, and shifting disaster needs in developing a system for delivering DBH services. Based on the adaptive governance framework, it argues that existing protocols such as the National Incident Management System (NIMS) and Incident Command System (ICS) may be helpful in advancing collective action, but that real progress will depend on a recognition of norms, expectations, and credentials across many spheres-in other words, on the ability of responders to continuously adjust their procedures and administrative boundaries for behavioural health institutions. PMID:22066735

  8. Ferrofluid based deformable mirrors: a new approach to adaptive optics using liquid mirrors

    NASA Astrophysics Data System (ADS)

    Laird, Phil R.; Bergamasco, R.; Bérubé, Vincent; Borra, Ermanno F.; Gingras, Julie; Ritcey, Anna-Marie R.; Rioux, Myriam; Robitaille, Nathalie; Thibault, Simon; Vieira da Silva, L., Jr.; Yockell-Lelièvre, Helene

    2003-02-01

    The trend towards ever larger telescopes and more advanced adaptive optics systems is driving the need for deformable mirrors with a large number of low cost actuators. Liquid mirrors have long been recognized a potential low cost alternative to conventional solid mirrors. By using a water or oil based ferrofluid we are able to benefit from a stronger magnetic response than is found in magnetic liquid metal amalgams and avoid the difficulty of passing a uniform current through a liquid. Depositing a thin silver colloid known as a metal liquid like film (MELLF) on the ferrofluid surface solves the problem of low reflectivity of pure ferrofluids. This combination provides a liquid optical surface that can be precisely shaped in a magnetic field. We present experimental results obtained with a prototype deformable liquid mirror based on this combination.

  9. Neuroelectric adaptations to cognitive processing in virtual environments: an exercise-related approach.

    PubMed

    Vogt, Tobias; Herpers, Rainer; Scherfgen, David; Strüder, Heiko K; Schneider, Stefan

    2015-04-01

    Recently, virtual environments (VEs) are suggested to encourage users to exercise regularly. The benefits of chronic exercise on cognitive performance are well documented in non-VE neurophysiological and behavioural studies. Based on event-related potentials (ERP) such as the N200 and P300, cognitive processing may be interpreted on a neuronal level. However, exercise-related neuroelectric adaptation in VE remains widely unclear and thus characterizes the primary aim of the present study. Twenty-two healthy participants performed active (moderate cycling exercise) and passive (no exercise) sessions in three VEs (control, front, surround), each generating a different sense of presence. Within sessions, conditions were randomly assigned, each lasting 5 min and including a choice reaction-time task to assess cognitive performance. According to the international 10:20 system, EEG with real-time triggered stimulus onset was recorded, and peaks of N200 and P300 components (amplitude, latency) were exported for analysis. Heart rate was recorded, and sense of presence assessed prior to and following each session and condition. Results revealed an increase in ERP amplitudes (N200: p < 0.001; P300: p < 0.001) and latencies (N200: p < 0.001) that were most pronounced over fronto-central and occipital electrode sites relative to an increased sense of presence (p < 0.001); however, ERP were not modulated by exercise (each p > 0.05). Hypothesized to mirror cognitive processing, decreases of cognitive performance's accuracy and reaction time failed significance. With respect to previous research, the present neuroelectric adaptation gives reason to believe in compensative neuronal resources that balance demanding cognitive processing in VE to avoid behavioural inefficiency. PMID:25630906

  10. Investigation of Yersinia pestis Laboratory Adaptation through a Combined Genomics and Proteomics Approach

    PubMed Central

    Clowers, Brian H.; Deatherage Kaiser, Brooke L.; Lin, Andy; Hutchison, Janine R.; Melville, Angela M.; Wagner, David M.; Keim, Paul S.; Foster, Jeffrey T.; Kreuzer, Helen W.

    2015-01-01

    The bacterial pathogen Yersinia pestis, the cause of plague in humans and animals, normally has a sylvatic lifestyle, cycling between fleas and mammals. In contrast, laboratory-grown Y. pestis experiences a more constant environment and conditions that it would not normally encounter. The transition from the natural environment to the laboratory results in a vastly different set of selective pressures, and represents what could be considered domestication. Understanding the kinds of adaptations Y. pestis undergoes as it becomes domesticated will contribute to understanding the basic biology of this important pathogen. In this study, we performed a parallel serial passage experiment (PSPE) to explore the mechanisms by which Y. pestis adapts to laboratory conditions, hypothesizing that cells would undergo significant changes in virulence and nutrient acquisition systems. Two wild strains were serially passaged in 12 independent populations each for ~750 generations, after which each population was analyzed using whole-genome sequencing, LC-MS/MS proteomic analysis, and GC/MS metabolomics. We observed considerable parallel evolution in the endpoint populations, detecting multiple independent mutations in ail, pepA, and zwf, suggesting that specific selective pressures are shaping evolutionary responses. Complementary LC-MS/MS proteomic data provide physiological context to the observed mutations, and reveal regulatory changes not necessarily associated with specific mutations, including changes in amino acid metabolism and cell envelope biogenesis. Proteomic data support hypotheses generated by genomic data in addition to suggesting future mechanistic studies, indicating that future whole-genome sequencing studies be designed to leverage proteomics as a critical complement. PMID:26599979

  11. Investigation of Yersinia pestis Laboratory Adaptation through a Combined Genomics and Proteomics Approach.

    PubMed

    Leiser, Owen P; Merkley, Eric D; Clowers, Brian H; Deatherage Kaiser, Brooke L; Lin, Andy; Hutchison, Janine R; Melville, Angela M; Wagner, David M; Keim, Paul S; Foster, Jeffrey T; Kreuzer, Helen W

    2015-01-01

    The bacterial pathogen Yersinia pestis, the cause of plague in humans and animals, normally has a sylvatic lifestyle, cycling between fleas and mammals. In contrast, laboratory-grown Y. pestis experiences a more constant environment and conditions that it would not normally encounter. The transition from the natural environment to the laboratory results in a vastly different set of selective pressures, and represents what could be considered domestication. Understanding the kinds of adaptations Y. pestis undergoes as it becomes domesticated will contribute to understanding the basic biology of this important pathogen. In this study, we performed a parallel serial passage experiment (PSPE) to explore the mechanisms by which Y. pestis adapts to laboratory conditions, hypothesizing that cells would undergo significant changes in virulence and nutrient acquisition systems. Two wild strains were serially passaged in 12 independent populations each for ~750 generations, after which each population was analyzed using whole-genome sequencing, LC-MS/MS proteomic analysis, and GC/MS metabolomics. We observed considerable parallel evolution in the endpoint populations, detecting multiple independent mutations in ail, pepA, and zwf, suggesting that specific selective pressures are shaping evolutionary responses. Complementary LC-MS/MS proteomic data provide physiological context to the observed mutations, and reveal regulatory changes not necessarily associated with specific mutations, including changes in amino acid metabolism and cell envelope biogenesis. Proteomic data support hypotheses generated by genomic data in addition to suggesting future mechanistic studies, indicating that future whole-genome sequencing studies be designed to leverage proteomics as a critical complement. PMID:26599979

  12. Investigation of Yersinia pestis Laboratory Adaptation through a Combined Genomics and Proteomics Approach.

    PubMed

    Leiser, Owen P; Merkley, Eric D; Clowers, Brian H; Deatherage Kaiser, Brooke L; Lin, Andy; Hutchison, Janine R; Melville, Angela M; Wagner, David M; Keim, Paul S; Foster, Jeffrey T; Kreuzer, Helen W

    2015-01-01

    The bacterial pathogen Yersinia pestis, the cause of plague in humans and animals, normally has a sylvatic lifestyle, cycling between fleas and mammals. In contrast, laboratory-grown Y. pestis experiences a more constant environment and conditions that it would not normally encounter. The transition from the natural environment to the laboratory results in a vastly different set of selective pressures, and represents what could be considered domestication. Understanding the kinds of adaptations Y. pestis undergoes as it becomes domesticated will contribute to understanding the basic biology of this important pathogen. In this study, we performed a parallel serial passage experiment (PSPE) to explore the mechanisms by which Y. pestis adapts to laboratory conditions, hypothesizing that cells would undergo significant changes in virulence and nutrient acquisition systems. Two wild strains were serially passaged in 12 independent populations each for ~750 generations, after which each population was analyzed using whole-genome sequencing, LC-MS/MS proteomic analysis, and GC/MS metabolomics. We observed considerable parallel evolution in the endpoint populations, detecting multiple independent mutations in ail, pepA, and zwf, suggesting that specific selective pressures are shaping evolutionary responses. Complementary LC-MS/MS proteomic data provide physiological context to the observed mutations, and reveal regulatory changes not necessarily associated with specific mutations, including changes in amino acid metabolism and cell envelope biogenesis. Proteomic data support hypotheses generated by genomic data in addition to suggesting future mechanistic studies, indicating that future whole-genome sequencing studies be designed to leverage proteomics as a critical complement.

  13. Investigation of Yersinia pestis laboratory adaptation through a combined genomics and proteomics approach

    DOE PAGES

    Leiser, Owen P.; Merkley, Eric D.; Clowers, Brian H.; Kaiser, Brooke L. Deatherage; Lin, Andy; Hutchison, Janine R.; Melville, Angela M.; Wagner, David M.; Keim, Paul S.; Foster, Jeff; et al

    2015-11-24

    Here, the bacterial pathogen Yersinia pestis, the cause of plague in humans and animals, normally has a sylvatic lifestyle, cycling between fleas and mammals. In contrast, laboratory-grown Y. pestis experiences a more constant environment and conditions that it would not normally encounter. The transition from the natural environment to the laboratory results in a vastly different set of selective pressures, and represents what could be considered domestication. Understanding the kinds of adaptations Y. pestis undergoes as it becomes domesticated will contribute to understanding the basic biology of this important pathogen. In this study, we performed a Parallel Serial Passage Experimentmore » (PSPE) to explore the mechanisms by which Y. pestis adapts to laboratory conditions, hypothesizing that cells would undergo significant changes in virulence and nutrient acquisition systems. Two wild strains were serially passaged in 12 independent populations each for ~750 generations, after which each population was analyzed using whole-genome sequencing. We observed considerable parallel evolution in the endpoint populations, detecting multiple independent mutations in ail, pepA, and zwf, suggesting that specific selective pressures are shaping evolutionary responses. Complementary LC-MS-based proteomic data provide physiological context to the observed mutations, and reveal regulatory changes not necessarily associated with specific mutations, including changes in amino acid metabolism, envelope biogenesis, iron storage and acquisition, and a type VI secretion system. Proteomic data support hypotheses generated by genomic data in addition to suggesting future mechanistic studies, indicating that future whole-genome sequencing studies be designed to leverage proteomics as a critical complement.« less

  14. Neuroelectric adaptations to cognitive processing in virtual environments: an exercise-related approach.

    PubMed

    Vogt, Tobias; Herpers, Rainer; Scherfgen, David; Strüder, Heiko K; Schneider, Stefan

    2015-04-01

    Recently, virtual environments (VEs) are suggested to encourage users to exercise regularly. The benefits of chronic exercise on cognitive performance are well documented in non-VE neurophysiological and behavioural studies. Based on event-related potentials (ERP) such as the N200 and P300, cognitive processing may be interpreted on a neuronal level. However, exercise-related neuroelectric adaptation in VE remains widely unclear and thus characterizes the primary aim of the present study. Twenty-two healthy participants performed active (moderate cycling exercise) and passive (no exercise) sessions in three VEs (control, front, surround), each generating a different sense of presence. Within sessions, conditions were randomly assigned, each lasting 5 min and including a choice reaction-time task to assess cognitive performance. According to the international 10:20 system, EEG with real-time triggered stimulus onset was recorded, and peaks of N200 and P300 components (amplitude, latency) were exported for analysis. Heart rate was recorded, and sense of presence assessed prior to and following each session and condition. Results revealed an increase in ERP amplitudes (N200: p < 0.001; P300: p < 0.001) and latencies (N200: p < 0.001) that were most pronounced over fronto-central and occipital electrode sites relative to an increased sense of presence (p < 0.001); however, ERP were not modulated by exercise (each p > 0.05). Hypothesized to mirror cognitive processing, decreases of cognitive performance's accuracy and reaction time failed significance. With respect to previous research, the present neuroelectric adaptation gives reason to believe in compensative neuronal resources that balance demanding cognitive processing in VE to avoid behavioural inefficiency.

  15. Early Fuel Cell Market Deployments: ARRA and Combined (IAA, DLA, ARRA): Quarter 4 2013 Composite Data Products

    SciTech Connect

    Kurtz, J.; Sprik, S.

    2014-06-01

    This report includes the composite data products (CDPs) for early fuel cell market deployments in quarter 4 of 2013. Results are presented for ARRA (projects funded by the American Recovery and Reinvestment Act of 2009 [ARRA]) and Combined (projects funded by DOE Interagency Agreements [IAA], Department of Defense Defense Logistics Agency [DLA], and ARRA).

  16. Early Fuel Cell Market Deployments: ARRA and Combined (IAA, DLA, ARRA); Quarter 3 2012 Composite Data Products

    SciTech Connect

    Kurtz, J.; Wipke, K.; Sprik, S.; Ramsden, T.; Ainscough, C.; Saur, G.; Post, M.

    2013-01-01

    This report from the U.S. Department of Energy's National Renewable Energy Laboratory includes early fuel cell market composite data products for the third quarter of 2012 for American Recovery and Reinvestment Act (ARRA) and combined (IAA, DLA, ARRA) deployment projects.

  17. Brassinosteroids regulate the differential growth of Arabidopsis hypocotyls through auxin signaling components IAA19 and ARF7.

    PubMed

    Zhou, Xiao-Yi; Song, Li; Xue, Hong-Wei

    2013-05-01

    Brassinosteroids (BRs) are an important class of phytohormones which regulates a wide range of physiological processes. Genetic and physiological studies have revealed that BR responses usually depend on an intact auxin signaling pathway. Here, we demonstrate that high BR concentration or enhanced BR signaling induce the differential growth of etiolated hypocotyls and result in the morphological changes, while auxin-resistant mutants, msg2 (dominant mutant of IAA19) and arf7, are insensitive to the BR effect and can partially suppress the phenotype of bzr1-D (dominant mutant of BZR1 with enhanced BR signaling). Interestingly, BZR1 protein can directly bind to the promoter regions of both IAA19 and ARF7, indicating that IAA19 and ARF7 mediate the BR-induced differential growth by serving as direct targets of BZR1. Systemic microarray analysis revealed that a number of BR-responsive genes showed reduced BR response in msg2, confirming that BR employs auxin signaling components IAA19 and ARF7 to modulate the specific downstream processes. These results provide informative clues on the crosstalk of BR-auxin signaling and the mechanisms of BR-auxin effects in regulating differential growth.

  18. GA4 and IAA were involved in the morphogenesis and development of flowers in Agapanthus praecox ssp. orientalis.

    PubMed

    Zhang, Di; Ren, Li; Yue, Jian-hua; Wang, Ling; Zhuo, Li-huan; Shen, Xiao-hui

    2014-07-01

    The transition from vegetative to reproductive growth represents a major phase change in angiosperms. Hormones play important roles in this process. In this study, gibberellic acid (GA), cytokinins (CKs), indoleacetic acid (IAA), and abscisic acid (ABA) were analyzed during the flowering in Agapanthus praecox ssp. orientalis. Eleven types of endogenous gibberellins in addition to GA1 were detected in various organs. GA9 was detected with the highest concentrations, followed by GA5, GA8, and GA19. However, GA4 was the main bioactive GA that was involved in the regulation of flowering. Eight types of endogenous cytokinins were detected in A. praecox ssp. orientalis, and zeatin, zeatin riboside, zeatin-O-glucoside, and N(6)-isopentenyladenosine-5-monophosphate were present at higher levels throughout the study, of which zeatin plays an important role in the development of various organs. IAA increased by 581% in the shoot tips from the vegetative to inflorescence bud stages and had the most significant changes during flowering. Phytohormone immunolocalization analysis suggested that IAA involved in differentiation and development of each floral organs, GA and zeatin play important roles in floret primordia differentiation and ovule development. Using exogenous plant growth regulators proved that GA signaling regulate the scape elongation and stimulate early-flowering, and IAA signaling is involved in the pedicel and corolla elongation and delay flowering slightly. PMID:24913054

  19. Native Prairie Adaptive Management: a multi region adaptive approach to invasive plant management on Fish and Wildlife Service owned native prairies

    USGS Publications Warehouse

    Gannon, Jill J.; Shaffer, Terry L.; Moore, Clinton T.

    2013-01-01

    Much of the native prairie managed by the U.S. Fish and Wildlife Service (FWS) in the Prairie Pothole Region (PPR) of the northern Great Plains is extensively invaded by the introduced cool-season grasses, smooth brome (Bromus inermis) and Kentucky bluegrass (Poa pratensis). Management to suppress these invasive plants has had poor to inconsistent success. The central challenge to managers is selecting appropriate management actions in the face of biological and environmental uncertainties. In partnership with the FWS, the U.S. Geological Survey (USGS) developed an adaptive decision support framework to assist managers in selecting management actions under uncertainty and maximizing learning from management outcomes. This joint partnership is known as the Native Prairie Adaptive Management (NPAM) initiative. The NPAM decision framework is built around practical constraints faced by FWS refuge managers and includes identification of the management objective and strategies, analysis of uncertainty and construction of competing decision models, monitoring, and mechanisms for model feedback and decision selection. Nineteen FWS field stations, spanning four states of the PPR, have participated in the initiative. These FWS cooperators share a common management objective, available management strategies, and biological uncertainties. Though the scope is broad, the initiative interfaces with individual land managers who provide site-specific information and receive updated decision guidance that incorporates understanding gained from the collective experience of all cooperators. We describe the technical components of this approach, how the components integrate and inform each other, how data feedback from individual cooperators serves to reduce uncertainty across the whole region, and how a successful adaptive management project is coordinated and maintained on a large scale. During an initial scoping workshop, FWS cooperators developed a consensus management objective

  20. An Adaptive Community-Based Participatory Approach to Formative Assessment with High Schools for Obesity Intervention

    ERIC Educational Resources Information Center

    Kong, Alberta S.; Farnsworth, Seth; Canaca, Jose A.; Harris, Amanda; Palley, Gabriel; Sussman, Andrew L.

    2012-01-01

    Background: In the emerging debate around obesity intervention in schools, recent calls have been made for researchers to include local community opinions in the design of interventions. Community-based participatory research (CBPR) is an effective approach for forming community partnerships and integrating local opinions. We used CBPR principles…

  1. Adapting a Problem-Solving Approach to Teaching Mathematics to Students with Mild Disabilities.

    ERIC Educational Resources Information Center

    Salend, Spencer J.; Hofstetter, Elaine

    1996-01-01

    Guidelines for implementing a problem-solving approach to teaching mathematics concepts and skills to students with mild disabilities include: establish connections to daily life; use visual presentations; use manipulatives; use peer-mediated instruction; provide models, cues, and prompts; teach self-management techniques and learning strategies;…

  2. A Fuzzy Genetic Algorithm Approach to an Adaptive Information Retrieval Agent.

    ERIC Educational Resources Information Center

    Martin-Bautista, Maria J.; Vila, Maria-Amparo; Larsen, Henrik Legind

    1999-01-01

    Presents an approach to a Genetic Information Retrieval Agent Filter (GIRAF) that filters and ranks documents retrieved from the Internet according to users' preferences by using a Genetic Algorithm and fuzzy set theory to handle the imprecision of users' preferences and users' evaluation of the retrieved documents. (Author/LRW)

  3. Towards an Agile Approach to Adapting Dynamic Collaboration Support to Student Needs

    ERIC Educational Resources Information Center

    Adamson, David; Dyke, Gregory; Jang, Hyeju; Rosé, Carolyn Penstein

    2014-01-01

    This paper investigates the use of conversational agents to scaffold on-line collaborative learning discussions through an approach called Academically Productive Talk (APT). In contrast to past work on dynamic support for collaborative learning, where agents were used to elevate conceptual depth by leading students through directed lines of…

  4. Biologically-inspired approaches for self-organization, adaptation, and collaboration of heterogeneous autonomous systems

    NASA Astrophysics Data System (ADS)

    Steinberg, Marc

    2011-06-01

    This paper presents a selective survey of theoretical and experimental progress in the development of biologicallyinspired approaches for complex surveillance and reconnaissance problems with multiple, heterogeneous autonomous systems. The focus is on approaches that may address ISR problems that can quickly become mathematically intractable or otherwise impractical to implement using traditional optimization techniques as the size and complexity of the problem is increased. These problems require dealing with complex spatiotemporal objectives and constraints at a variety of levels from motion planning to task allocation. There is also a need to ensure solutions are reliable and robust to uncertainty and communications limitations. First, the paper will provide a short introduction to the current state of relevant biological research as relates to collective animal behavior. Second, the paper will describe research on largely decentralized, reactive, or swarm approaches that have been inspired by biological phenomena such as schools of fish, flocks of birds, ant colonies, and insect swarms. Next, the paper will discuss approaches towards more complex organizational and cooperative mechanisms in team and coalition behaviors in order to provide mission coverage of large, complex areas. Relevant team behavior may be derived from recent advances in understanding of the social and cooperative behaviors used for collaboration by tens of animals with higher-level cognitive abilities such as mammals and birds. Finally, the paper will briefly discuss challenges involved in user interaction with these types of systems.

  5. An Adaptive Cooperative Strategy for Underlay MIMO Cognitive Radio Networks: An Opportunistic and Low-Complexity Approach

    NASA Astrophysics Data System (ADS)

    Mazoochi, M.; Pourmina, M. A.; Bakhshi, H.

    2015-03-01

    The core aim of this work is the maximization of the achievable data rate of the secondary user pairs (SU pairs), while ensuring the QoS of primary users (PUs). All users are assumed to be equipped with multiple antennas. It is assumed that when PUs are present, the direct communications between SU pairs introduces intolerable interference to PUs and thereby SUs transmit signal using the cooperation of other SUs and avoid transmitting in the direct channel. In brief, an adaptive cooperative strategy for multiple-input/multiple-output (MIMO) cognitive radio networks is proposed. At the presence of PUs, the issue of joint relay selection and power allocation in Underlay MIMO Cooperative Cognitive Radio Networks (U-MIMO-CCRN) is addressed. The optimal approach for determining the power allocation and the cooperating SU is proposed. Besides, the outage probability of the proposed communication protocol is further derived. Due to high complexity of the optimal approach, a low-complexity approach is further proposed and its performance is evaluated using simulations. The simulation results reveal that the performance loss due to the low-complexity approach is only about 14%, while the complexity is greatly reduced.

  6. Lapses, infidelities, and creative adaptations: lessons from evaluation of a participatory market development approach in the Andes.

    PubMed

    Horton, Douglas; Rotondo, Emma; Paz Ybarnegaray, Rodrigo; Hareau, Guy; Devaux, André; Thiele, Graham

    2013-08-01

    Participatory approaches are frequently recommended for international development programs, but few have been evaluated. From 2007 to 2010 the Andean Change Alliance evaluated an agricultural research and development approach known as the "Participatory Market Chain Approach" (PMCA). Based on a study of four cases, this paper examines the fidelity of implementation, the factors that influenced implementation and results, and the PMCA change model. We identify three types of deviation from the intervention protocol (lapses, creative adaptations, and true infidelities) and five groups of variables that influenced PMCA implementation and results (attributes of the macro context, the market chain, the key actors, rules in use, and the capacity development strategy). There was insufficient information to test the validity of the PMCA change model, but results were greatest where the PMCA was implemented with highest fidelity. Our analysis suggests that the single most critical component of the PMCA is engagement of market agents - not just farmers - throughout the exercise. We present four lessons for planning and evaluating participatory approaches related to the use of action and change models, the importance of monitoring implementation fidelity, the limits of baseline survey data for outcome evaluation, and the importance of capacity development for implementers. PMID:23619235

  7. Lapses, infidelities, and creative adaptations: lessons from evaluation of a participatory market development approach in the Andes.

    PubMed

    Horton, Douglas; Rotondo, Emma; Paz Ybarnegaray, Rodrigo; Hareau, Guy; Devaux, André; Thiele, Graham

    2013-08-01

    Participatory approaches are frequently recommended for international development programs, but few have been evaluated. From 2007 to 2010 the Andean Change Alliance evaluated an agricultural research and development approach known as the "Participatory Market Chain Approach" (PMCA). Based on a study of four cases, this paper examines the fidelity of implementation, the factors that influenced implementation and results, and the PMCA change model. We identify three types of deviation from the intervention protocol (lapses, creative adaptations, and true infidelities) and five groups of variables that influenced PMCA implementation and results (attributes of the macro context, the market chain, the key actors, rules in use, and the capacity development strategy). There was insufficient information to test the validity of the PMCA change model, but results were greatest where the PMCA was implemented with highest fidelity. Our analysis suggests that the single most critical component of the PMCA is engagement of market agents - not just farmers - throughout the exercise. We present four lessons for planning and evaluating participatory approaches related to the use of action and change models, the importance of monitoring implementation fidelity, the limits of baseline survey data for outcome evaluation, and the importance of capacity development for implementers.

  8. Performance Monitoring and Assessment of Neuro-Adaptive Controllers for Aerospace Applications Using a Bayesian Approach

    NASA Technical Reports Server (NTRS)

    Gupta, Pramod; Jacklin, Stephen; Schumann, Johann; Guenther, Kurt; Richard, Michael; Soares, Fola

    2005-01-01

    Modem aircraft, UAVs, and robotic spacecraft pose substantial requirements on controllers in the light of ever increasing demands for reusability, affordability, and reliability. The individual systems (which are often nonlinear) must be controlled safely and reliably in environments where it is virtually impossible to analyze-ahead of time- all the important and possible scenarios and environmental factors. For example, system components (e.g., gyros, bearings of reaction wheels, valves) may deteriorate or break during autonomous UAV operation or long-lasting space missions, leading to a sudden, drastic change in vehicle performance. Manual repair or replacement is not an option in such cases. Instead, the system must be able to cope with equipment failure and deterioration. Controllability of the system must be retained as good as possible or re-established as fast as possible with a minimum of deactivation or shutdown of the system being controlled. In such situations the control engineer has to employ adaptive control systems that automatically sense and correct themselves whenever drastic disturbances and/or severe changes in the plant or environment occur.

  9. Dynamic scenario of metabolic pathway adaptation in tumors and therapeutic approach

    PubMed Central

    Peppicelli, Silvia; Bianchini, Francesca; Calorini, Lido

    2015-01-01

    Cancer cells need to regulate their metabolic program to fuel several activities, including unlimited proliferation, resistance to cell death, invasion and metastasis. The aim of this work is to revise this complex scenario. Starting from proliferating cancer cells located in well-oxygenated regions, they may express the so-called “Warburg effect” or aerobic glycolysis, meaning that although a plenty of oxygen is available, cancer cells choose glycolysis, the sole pathway that allows a biomass formation and DNA duplication, needed for cell division. Although oxygen does not represent the primary font of energy, diffusion rate reduces oxygen tension and the emerging hypoxia promotes “anaerobic glycolysis” through the hypoxia inducible factor-1α-dependent up-regulation. The acquired hypoxic phenotype is endowed with high resistance to cell death and high migration capacities, although these cells are less proliferating. Cells using aerobic or anaerobic glycolysis survive only in case they extrude acidic metabolites acidifying the extracellular space. Acidosis drives cancer cells from glycolysis to OxPhos, and OxPhos transforms the available alternative substrates into energy used to fuel migration and distant organ colonization. Thus, metabolic adaptations sustain different energy-requiring ability of cancer cells, but render them responsive to perturbations by anti-metabolic agents, such as inhibitors of glycolysis and/or OxPhos. PMID:25897425

  10. Dynamic scenario of metabolic pathway adaptation in tumors and therapeutic approach.

    PubMed

    Peppicelli, Silvia; Bianchini, Francesca; Calorini, Lido

    2015-01-01

    Cancer cells need to regulate their metabolic program to fuel several activities, including unlimited proliferation, resistance to cell death, invasion and metastasis. The aim of this work is to revise this complex scenario. Starting from proliferating cancer cells located in well-oxygenated regions, they may express the so-called "Warburg effect" or aerobic glycolysis, meaning that although a plenty of oxygen is available, cancer cells choose glycolysis, the sole pathway that allows a biomass formation and DNA duplication, needed for cell division. Although oxygen does not represent the primary font of energy, diffusion rate reduces oxygen tension and the emerging hypoxia promotes "anaerobic glycolysis" through the hypoxia inducible factor-1α-dependent up-regulation. The acquired hypoxic phenotype is endowed with high resistance to cell death and high migration capacities, although these cells are less proliferating. Cells using aerobic or anaerobic glycolysis survive only in case they extrude acidic metabolites acidifying the extracellular space. Acidosis drives cancer cells from glycolysis to OxPhos, and OxPhos transforms the available alternative substrates into energy used to fuel migration and distant organ colonization. Thus, metabolic adaptations sustain different energy-requiring ability of cancer cells, but render them responsive to perturbations by anti-metabolic agents, such as inhibitors of glycolysis and/or OxPhos. PMID:25897425

  11. Space communications scheduler: A rule-based approach to adaptive deadline scheduling

    NASA Technical Reports Server (NTRS)

    Straguzzi, Nicholas

    1990-01-01

    Job scheduling is a deceptively complex subfield of computer science. The highly combinatorial nature of the problem, which is NP-complete in nearly all cases, requires a scheduling program to intelligently transverse an immense search tree to create the best possible schedule in a minimal amount of time. In addition, the program must continually make adjustments to the initial schedule when faced with last-minute user requests, cancellations, unexpected device failures, quests, cancellations, unexpected device failures, etc. A good scheduler must be quick, flexible, and efficient, even at the expense of generating slightly less-than-optimal schedules. The Space Communication Scheduler (SCS) is an intelligent rule-based scheduling system. SCS is an adaptive deadline scheduler which allocates modular communications resources to meet an ordered set of user-specified job requests on board the NASA Space Station. SCS uses pattern matching techniques to detect potential conflicts through algorithmic and heuristic means. As a result, the system generates and maintains high density schedules without relying heavily on backtracking or blind search techniques. SCS is suitable for many common real-world applications.

  12. Multi-frequency Phase Unwrap from Noisy Data: Adaptive Least Squares Approach

    NASA Astrophysics Data System (ADS)

    Katkovnik, Vladimir; Bioucas-Dias, José

    2010-04-01

    Multiple frequency interferometry is, basically, a phase acquisition strategy aimed at reducing or eliminating the ambiguity of the wrapped phase observations or, equivalently, reducing or eliminating the fringe ambiguity order. In multiple frequency interferometry, the phase measurements are acquired at different frequencies (or wavelengths) and recorded using the corresponding sensors (measurement channels). Assuming that the absolute phase to be reconstructed is piece-wise smooth, we use a nonparametric regression technique for the phase reconstruction. The nonparametric estimates are derived from a local least squares criterion, which, when applied to the multifrequency data, yields denoised (filtered) phase estimates with extended ambiguity (periodized), compared with the phase ambiguities inherent to each measurement frequency. The filtering algorithm is based on local polynomial (LPA) approximation for design of nonlinear filters (estimators) and adaptation of these filters to unknown smoothness of the spatially varying absolute phase [9]. For phase unwrapping, from filtered periodized data, we apply the recently introduced robust (in the sense of discontinuity preserving) PUMA unwrapping algorithm [1]. Simulations give evidence that the proposed algorithm yields state-of-the-art performance for continuous as well as for discontinues phase surfaces, enabling phase unwrapping in extraordinary difficult situations when all other algorithms fail.

  13. A computer adaptive testing approach for assessing physical functioning in children and adolescents.

    PubMed

    Haley, Stephen M; Ni, Pengsheng; Fragala-Pinkham, Maria A; Skrinar, Alison M; Corzo, Deyanira

    2005-02-01

    The purpose of this article is to demonstrate: (1) the accuracy and (2) the reduction in amount of time and effort in assessing physical functioning (self-care and mobility domains) of children and adolescents using computer-adaptive testing (CAT). A CAT algorithm selects questions directly tailored to the child's ability level, based on previous responses. Using a CAT algorithm, a simulation study was used to determine the number of items necessary to approximate the score of a full-length assessment. We built simulated CAT (5-, 10-, 15-, and 20-item versions) for self-care and mobility domains and tested their accuracy in a normative sample (n=373; 190 males, 183 females; mean age 6y 11mo [SD 4y 2m], range 4mo to 14y 11mo) and a sample of children and adolescents with Pompe disease (n=26; 21 males, 5 females; mean age 6y 1mo [SD 3y 10mo], range 5mo to 14y 10mo). Results indicated that comparable score estimates (based on computer simulations) to the full-length tests can be achieved in a 20-item CAT version for all age ranges and for normative and clinical samples. No more than 13 to 16% of the items in the full-length tests were needed for any one administration. These results support further consideration of using CAT programs for accurate and efficient clinical assessments of physical functioning.

  14. A new adaptive control approach for aerospace vehicles with parameter uncertainties

    NASA Technical Reports Server (NTRS)

    Hahn, Yungsun; Speyer, Jason L.

    1989-01-01

    A new stochastic adaptive control structure is developed for the problem of combined parameter estimation and control of aerospace vehicles with changing parameters. Parameter uncertainties are modeled as first-order Gauss-Markov processes, and are introduced to the system dynamics through a small parameter. It is assumed that an accurate inertial measurement unit gives perfect measurements of the state variables. Since the stochastic system is assumed to be Gauss-Markov, the density function of the parameters given these measurements is conditionally Gaussian. Based on this conditionally Gaussian density, the problem of minimizing a quadratic cost over an infinite time horizon can be set up within the framework of stochastic optimal control theory. The optimal feedback control law is derived from a straightforward expansion of the Hamilton-Jacobi-Bellman equation, based on the LQG solution. The resulting nonlinear controller is applied to the pitch axis control of a space platform with uncertain moments of inertia and is shown to produce marked improvement over a fixed controller.

  15. A socio-ecological adaptive approach to contaminated mega-site management: From 'control and correct' to 'coping with change'

    NASA Astrophysics Data System (ADS)

    Schirmer, Mario; Lyon, Ken; Armstrong, James E.; Farrell, Katharine N.

    2012-01-01

    Mega-sites have a notable impact on surrounding ecological systems. At such sites there are substantial risks associated with complex socio-ecological interactions that are hard to characterize, let alone model and predict. While the urge to control and clean-up mega-sites (control and correct) is understandable, rather than setting a goal of cleaning up such sites, we suggest a more realistic response strategy is to address these massive and persistent sources of contamination by acknowledging their position as new features of the socio-ecological landscapes within which they are located. As it seems nearly impossible to clean up such sites, we argue for consideration of a 'coping with change' rather than a 'control and correct' approach. This strategy recognizes that the current management option for a mega-site, in light of its physical complexities and due to changing societal preferences, geochemical transformations, hydrogeology knowledge and remedial technology options may not remain optimal in future, and therefore needs to be continuously adapted, as community, ecology, technology and understanding change over time. This approach creates an opportunity to consider the relationship between a mega-site and its human and ecological environments in a different and more dynamic way. Our proposed approach relies on iterative adaptive management to incorporate mega-site management into the overall socio-ecological systems of the site's context. This approach effectively embeds mega-site management planning in a triple bottom line and environmental sustainability structure, rather than simply using single measures of success, such as contaminant-based guidelines. Recognizing that there is probably no best solution for managing a mega-site, we present a starting point for engaging constructively with this seemingly intractable issue. Therefore, we aim to initiate discussion about a new approach to mega-site management, in which the complexity of the problems posed

  16. A socio-ecological adaptive approach to contaminated mega-site management: from 'control and correct' to 'coping with change'.

    PubMed

    Schirmer, Mario; Lyon, Ken; Armstrong, James E; Farrell, Katharine N

    2012-01-01

    Mega-sites have a notable impact on surrounding ecological systems. At such sites there are substantial risks associated with complex socio-ecological interactions that are hard to characterize, let alone model and predict. While the urge to control and clean-up mega-sites (control and correct) is understandable, rather than setting a goal of cleaning up such sites, we suggest a more realistic response strategy is to address these massive and persistent sources of contamination by acknowledging their position as new features of the socio-ecological landscapes within which they are located. As it seems nearly impossible to clean up such sites, we argue for consideration of a 'coping with change' rather than a 'control and correct' approach. This strategy recognizes that the current management option for a mega-site, in light of its physical complexities and due to changing societal preferences, geochemical transformations, hydrogeology knowledge and remedial technology options may not remain optimal in future, and therefore needs to be continuously adapted, as community, ecology, technology and understanding change over time. This approach creates an opportunity to consider the relationship between a mega-site and its human and ecological environments in a different and more dynamic way. Our proposed approach relies on iterative adaptive management to incorporate mega-site management into the overall socio-ecological systems of the site's context. This approach effectively embeds mega-site management planning in a triple bottom line and environmental sustainability structure, rather than simply using single measures of success, such as contaminant-based guidelines. Recognizing that there is probably no best solution for managing a mega-site, we present a starting point for engaging constructively with this seemingly intractable issue. Therefore, we aim to initiate discussion about a new approach to mega-site management, in which the complexity of the problems posed

  17. Vulnerability assessment in a participatory approach to design and implement community based adaptation to drought in the Peruvian Andes

    NASA Astrophysics Data System (ADS)

    Lasage, Ralph; Muis, Sanne; Sardella, Carolina; van Drunen, Michiel; Verburg, Peter; Aerts, Jeroen

    2015-04-01

    The livelihoods of people in the Andes are expected to be affected by climate change due to their dependence on glacier meltwater during the growing season. The observed decrease in glacier volume over the last few decades is likely to accelerate during the current century, which will affect water availability in the region. This paper presents the implementation of an approach for the participatory development of community-based adaptation measures to cope with the projected impacts of climate change, which was implemented jointly by the local community and by a team consisting of an NGO, Peruvian ministry of environment, research organisations and a private sector organisation. It bases participatory design on physical measurements, modelling and a vulnerability analysis. Vulnerability to drought is made operational for households in a catchment of the Ocoña river basin in Peru. On the basis of a household survey we explore how a vulnerability index (impacts divided by the households' perceived adaptive capacity) can be used to assess the distribution of vulnerability over households in a sub catchment. The socio-economic factors water entitlement, area of irrigated land, income and education are all significantly correlate with this vulnerability to drought. The index proved to be appropriate for communicating about vulnerability to climate change and its determining factors with different stakeholders. The water system research showed that the main source of spring water is local rainwater, and that water use efficiency in farming is low. The adaptation measures that were jointly selected by the communities and the project team aimed to increase water availability close to farmland, and increase water use efficiency, and these will help to reduce the communities vulnerability to drought.

  18. A covariance-adaptive approach for regularized inversion in linear models

    NASA Astrophysics Data System (ADS)

    Kotsakis, Christopher

    2007-11-01

    The optimal inversion of a linear model under the presence of additive random noise in the input data is a typical problem in many geodetic and geophysical applications. Various methods have been developed and applied for the solution of this problem, ranging from the classic principle of least-squares (LS) estimation to other more complex inversion techniques such as the Tikhonov-Philips regularization, truncated singular value decomposition, generalized ridge regression, numerical iterative methods (Landweber, conjugate gradient) and others. In this paper, a new type of optimal parameter estimator for the inversion of a linear model is presented. The proposed methodology is based on a linear transformation of the classic LS estimator and it satisfies two basic criteria. First, it provides a solution for the model parameters that is optimally fitted (in an average quadratic sense) to the classic LS parameter solution. Second, it complies with an external user-dependent constraint that specifies a priori the error covariance (CV) matrix of the estimated model parameters. The formulation of this constrained estimator offers a unified framework for the description of many regularization techniques that are systematically used in geodetic inverse problems, particularly for those methods that correspond to an eigenvalue filtering of the ill-conditioned normal matrix in the underlying linear model. Our study lies on the fact that it adds an alternative perspective on the statistical properties and the regularization mechanism of many inversion techniques commonly used in geodesy and geophysics, by interpreting them as a family of `CV-adaptive' parameter estimators that obey a common optimal criterion and differ only on the pre-selected form of their error CV matrix under a fixed model design.

  19. Time course of salinity adaptation in a strongly euryhaline estuarine teleost, fundulus heteroclitus: A multivariable approach

    USGS Publications Warehouse

    Marshall, W.S.; Emberley, T.R.; Singer, T.D.; Bryson, S.E.; McCormick, S.D.

    1999-01-01

    Freshwater-adapted killifish (Fundulus heteroclitus) were transferred directly from soft fresh water to full-strength sea water for periods of 1h, 3h, 8h and 1, 2, 7, 14 and 30 days. Controls were transferred to fresh water for 24 h. Measured variables included: blood [Na+], osmolality, glucose and cortisol levels, basal and stimulated rates of ion transport and permeability of in vitro opercular epithelium, gill Na+/K+-ATPase and citrate synthase activity and chloride cell ultrastructure. These data were compared with previously published killifish cystic fibrosis transmembrane conductance regulator (kfCFTR) expression in the gills measured over a similar time course. Plasma cortisol levels peaked at 1 h, coincident with a rise in plasma [Na+]. At 8 h after transfer to sea water, a time at which previous work has shown kfCFTR expression to be elevated, blood osmolality and [Na+] were high, and cortisol levels and opercular membrane short-circuit current (I(SC); a measure of Cl- secretion rate) were low. The 24h group, which showed the highest level of kfCFTR expression, had the highest plasma [Na+] and osmolality, elevated plasma cortisol levels, significantly lower opercular membrane resistance, an increased opercular membrane ion secretion rate and collapsed tubule inclusions in mitochondria-rich cells, but no change in gill Na+/K+-ATPase and citrate synthase activity or plasma glucose levels. Apparently, killifish have a rapid (<1h) cortisol response to salinity coupled to subsequent (8-48 h) expression of kfCFTR anion channel proteins in existing mitochondria-rich cells that convert transport from ion uptake to ion secretion.

  20. Crop planting date optimization: An approach for climate change adaptation in West Africa

    NASA Astrophysics Data System (ADS)

    Waongo, Moussa; Laux, Patrick; Kunstmann, Harald

    2014-05-01

    Agriculture is the main source of income for population and the main driver of economy in Africa, particularly in West Africa. West African agriculture is dominated by rainfed agriculture. This agricultural system is characterized by smallholder and subsistence farming, and a limited use of crop production inputs such as machines, fertilizers and pesticides. Therefore, crop yield is strongly influenced by climate fluctuation and is more vulnerable to climate change and climate variability. To reduce climate risk on crop production, a development of tailored agricultural management strategies is required. The usage of agricultural management strategies such as tailored crop planting date might contribute both to reduce crop failure and to increased crop production. In addition, unlike aforementioned crop production inputs, the usage of tailored planting dates is costless for farmers. Thus, efforts to improve crop production by optimizing crop planting date can contribute to alleviate food insecurity in West Africa, in the context of climate change. In this study, the process-based crop model GLAM (General Large Area Model for annual crop) in combination with a fuzzy logic approach for planting date have been coupled with a genetic algorithm to derive Optimized Planting Dates (OPDs) for maize cropping in Burkina Faso, West Africa. For a specific location, the derived OPDs correspond to a time window for crop planting. To analyze the performance of the OPDs approach, the derived OPDs has been compared to two well-known planting date methods in West Africa. The results showed a mean OPD ranging from May 1st (South-West) to July 11th (North) across the country. In comparison with well-known methods, the OPD approach yielded earliest planting dates across Burkina Faso. The deviation of OPDs from planting dates derived from the well known methods ranged from 10 days to 20 days for the northern and central region, and less than 10 days for the southern region. With respect

  1. Adaptive Interface Approach Using a Real Time Biocybernetic System: Control of Hazardous Awareness

    NASA Technical Reports Server (NTRS)

    Ray, William J.

    2002-01-01

    The focus of this current grant was to continue our work which focused on the manner in which psychophysiological markers can be used to index hazardous states of awareness and to explore the feasibility of developing on-line systems that utilize real time feedback to modify on-going behavioral processes. In this work we have incorporated a multifaceted approach which includes psychophysiological, subjective, and performance based measures. We have considered this from both an internal and external perspective as reflected in work from a variety of labs.

  2. Adaptive neuro-fuzzy approach for predicting hardness of deposited TiN/ZrN multilayer coatings.

    PubMed

    Yang, Yu-Sen; Huang, Wesley; Huang, Guo-Ping; Chou, Jyh-Horng

    2010-07-01

    This paper presents an adaptive neuro-fuzzy approach based on first order function of fuzzy model for establishing the relationship between control factors and thin films properties of TiN/ZrN coatings on Si(100) wafer substrates. A statistical model was designed to explore the space of the processes by an orthogonal array scheme. Eight control factors of closed unbalance magnetron sputtering system were selected for modeling the process, such as interlayer material, argon and nitrogen flow rate, titanium and zirconium target current, rotation speed, work distance, and bias voltage. Analysis of variance (ANOVA) was carried out for determining the influence of control factors. In this study, with the application of ANOVA, the smallest effect of control factors was eliminated. The adaptive neuro-fuzzy inference system (ANFIS) was applied as a tool to model the deposited process with five significant control factors. The experimental results show that ANFIS demonstrates better accuracy than additive model for the film hardness. The root mean square error between prediction values and experimental values were archived to 0.04. PMID:21128476

  3. Optimizing the general linear model for functional near-infrared spectroscopy: an adaptive hemodynamic response function approach

    PubMed Central

    Uga, Minako; Dan, Ippeita; Sano, Toshifumi; Dan, Haruka; Watanabe, Eiju

    2014-01-01

    Abstract. An increasing number of functional near-infrared spectroscopy (fNIRS) studies utilize a general linear model (GLM) approach, which serves as a standard statistical method for functional magnetic resonance imaging (fMRI) data analysis. While fMRI solely measures the blood oxygen level dependent (BOLD) signal, fNIRS measures the changes of oxy-hemoglobin (oxy-Hb) and deoxy-hemoglobin (deoxy-Hb) signals at a temporal resolution severalfold higher. This suggests the necessity of adjusting the temporal parameters of a GLM for fNIRS signals. Thus, we devised a GLM-based method utilizing an adaptive hemodynamic response function (HRF). We sought the optimum temporal parameters to best explain the observed time series data during verbal fluency and naming tasks. The peak delay of the HRF was systematically changed to achieve the best-fit model for the observed oxy- and deoxy-Hb time series data. The optimized peak delay showed different values for each Hb signal and task. When the optimized peak delays were adopted, the deoxy-Hb data yielded comparable activations with similar statistical power and spatial patterns to oxy-Hb data. The adaptive HRF method could suitably explain the behaviors of both Hb parameters during tasks with the different cognitive loads during a time course, and thus would serve as an objective method to fully utilize the temporal structures of all fNIRS data. PMID:26157973

  4. Adapting a GIS-Based Multicriteria Decision Analysis Approach for Evaluating New Power Generating Sites

    SciTech Connect

    Omitaomu, Olufemi A; Blevins, Brandon R; Jochem, Warren C; Mays, Gary T; Belles, Randy; Hadley, Stanton W; Harrison, Thomas J; Bhaduri, Budhendra L; Neish, Bradley S; Rose, Amy N

    2012-01-01

    There is a growing need to site new power generating plants that use cleaner energy sources due to increased regulations on air and water pollution and a sociopolitical desire to develop more clean energy sources. To assist utility and energy companies as well as policy-makers in evaluating potential areas for siting new plants in the contiguous United States, a geographic information system (GIS)-based multicriteria decision analysis approach is presented in this paper. The presented approach has led to the development of the Oak Ridge Siting Analysis for power Generation Expansion (OR-SAGE) tool. The tool takes inputs such as population growth, water availability, environmental indicators, and tectonic and geological hazards to provide an in-depth analysis for siting options. To the utility and energy companies, the tool can quickly and effectively provide feedback on land suitability based on technology specific inputs. However, the tool does not replace the required detailed evaluation of candidate sites. To the policy-makers, the tool provides the ability to analyze the impacts of future energy technology while balancing competing resource use.

  5. EPR policies for electronics in developing Asia: an adapted phase-in approach.

    PubMed

    Akenji, Lewis; Hotta, Yasuhiko; Bengtsson, Magnus; Hayashi, Shiko

    2011-09-01

    The amount of e-waste is growing rapidly in developing countries, and the health and environmental problems resulting from poor management of this waste have become a concern for policy makers. In response to these challenges, a number of Asian developing countries have been inspired by policy developments in OECD countries, and have drafted legislations based on the principle of extended producer responsibility (EPR). However, the experiences from developed countries show that a successful implementation of EPR policies requires adequate institutions and sufficient administrative capacity. Even advanced countries are thus facing difficulties. This paper concludes from existing literature and from the authors' own observations that there seems to be a mismatch between the typical policy responses to e-waste problems in developing Asia and the capacity for successful implementation of such policies. It also notes that the e-waste situation in developing Asian countries is further complicated by a number of additional factors, such as difficulties in identifying producers, import of used electronic products and e-waste (sometimes illegal), and the existence of a strong informal waste sector. Given these challenges, the authors conclude that comprehensive EPR policy schemes of the kind that have been implemented in some advanced countries are not likely to be effective. The paper therefore proposes an alternative phase-in approach whereby developing Asian countries are able to move gradually towards EPR systems. It argues that this approach would be more feasible, and discusses what could be the key building blocks of each implementation stage. PMID:21730041

  6. An adaptive diffusion-weighted whole-body magnetic resonance imaging scheme using the multistation approach

    NASA Astrophysics Data System (ADS)

    Han, Yeji

    2016-02-01

    Whole-body diffusion-weighted imaging (DWI) is a useful tool in oncology, which enables fast screening of disseminated tumors, lymph nodes or abscesses in the body. Multistation magnetic resonance imaging (MRI) or continuously moving table (CMT) MRI can be performed to overcome the limited field of view (FOV) of the magnet bore in whole-body DWI. Although CMT-MRI is regarded as a more advanced form of whole-body MRI, it cannot be widely used because most of the available MR systems are not equipped with the required hardware/software to perform CMT. Thus, optimizing the multistation approach for whole-body DWI, which is more widely available and easier to perform with the existing MR systems, is worthwhile. To improve the quality of DW images acquired with the multistation approach, we used different combinations of the built-in body RF coil and the phased-array surface RF coils for reception of the signals in whole-body DWI in this work. If different coils are selectively used in the extended FOV and appropriate reconstruction algorithms are exploited, the screening ability of whole-body DWI can be improved while minimizing the patient's discomfort and the artifacts due to physiological motions.

  7. Space Weather Research at IAA/NOA: Solar Energetic Particle Investigations

    NASA Astrophysics Data System (ADS)

    Malandraki, O.; Tylka, A. J.; Ng, C. K.; Marsden, R. G.; Tranquille, C.; Klein, K. L.; Patterson, J. D.; Armstrong, T. P.; Lanzerotti, L. J.; Papaioannou, A.; Marhavilas, P. K.; Tziotziou, K.; Crosby, N.; Vainio, R.

    2012-01-01

    During an eleven year cycle the Sun goes from quiet conditions at minimum to levels of high activity at maximum. In the latter case, energetic phenomena such as coronal mass ejections (CMEs) and solar flares (SFs) accompanied by explosive releases of mass, magnetic flux and solar energetic particles (SEPs) are common. Damaging effects, as a result of these phenomena, have been recorded on satellites, on-board detectors and in extreme cases on ground based systems (e.g. oil and natural gas pipelines, communication systems, aircraft electronics, power-grids). Furthermore, the intense SEP radiation can damage human DNA and cause cell replications. To this end, ensuring the safety of astronauts working in the extreme conditions of space, especially the energetic particle environments, is a key goal for both ESA and NASA. The analysis, the risk assessment and management and the possible forecasting of such events constitutes the scientific field of Space Weather. The Institute of Astronomy and Astrophysics (IAA) of the National Observatory of Athens (NOA) is currently strongly involved in two collaborative projects funded by the seventh framework program of the European Union, namely: 'SEPServer' and 'COMESEP'. 'SEPServer' focuses on the implementation of a comprehensive and up to date SEP analysis service including scientific data driven analysis both for 1 AU and for > 1 AU using data from the SOHO/ ERNE, SOHO/EPHIN, ACE/EPAM, ACE/SIS, WIND/3DP, Ulysses/HISCALE, Ulysses/COSPIN/LET and Ulysses/COSPIN/KET experiments. SEPServer will also provide for the first time the release of the HELIOS data set in a reasonable format and in full time resolution, thus making available data also for orbits inside 1 AU (down to 0.3 AU). Observational data-driven analysis methods such as: onset determination, velocity dispersion, and/or time-shifting analysis, direct comparison of observed SEP fluxes, spectra and abundance ratios with the associated electromagnetic emission data will be

  8. Information-Theoretic Approaches for Evaluating Complex Adaptive Social Simulation Systems

    SciTech Connect

    Omitaomu, Olufemi A; Ganguly, Auroop R; Jiao, Yu

    2009-01-01

    In this paper, we propose information-theoretic approaches for comparing and evaluating complex agent-based models. In information theoretic terms, entropy and mutual information are two measures of system complexity. We used entropy as a measure of the regularity of the number of agents in a social class; and mutual information as a measure of information shared by two social classes. Using our approaches, we compared two analogous agent-based (AB) models developed for regional-scale social-simulation system. The first AB model, called ABM-1, is a complex AB built with 10,000 agents on a desktop environment and used aggregate data; the second AB model, ABM-2, was built with 31 million agents on a highperformance computing framework located at Oak Ridge National Laboratory, and fine-resolution data from the LandScan Global Population Database. The initializations were slightly different, with ABM-1 using samples from a probability distribution and ABM-2 using polling data from Gallop for a deterministic initialization. The geographical and temporal domain was present-day Afghanistan, and the end result was the number of agents with one of three behavioral modes (proinsurgent, neutral, and pro-government) corresponding to the population mindshare. The theories embedded in each model were identical, and the test simulations focused on a test of three leadership theories - legitimacy, coercion, and representative, and two social mobilization theories - social influence and repression. The theories are tied together using the Cobb-Douglas utility function. Based on our results, the hypothesis that performance measures can be developed to compare and contrast AB models appears to be supported. Furthermore, we observed significant bias in the two models. Even so, further tests and investigations are required not only with a wider class of theories and AB models, but also with additional observed or simulated data and more comprehensive performance measures.

  9. SU-E-E-07: An Adaptable Approach for Education On Medical Physics at Undergraduate and Postgraduate Levels

    SciTech Connect

    Miller-Clemente, R; Mendez-Perez, L

    2015-06-15

    Purpose: To contribute to the professional profile of future medical physicists, technologists and physicians, and implement an adaptable educational strategy at both undergraduate and postgraduate levels. Methods: The Medical Physics Block of Electives (MPBE) designed was adapted to the Program of B.S. in Physics. The conferences and practical activities were developed with participatory methods, with interdisciplinary collaboration from research institutions and hospitals engaged on projects of Research, Development and Innovation (RDI). The scientific education was implemented by means of critical analysis of scientific papers and seminars where students debated on solutions for real research problems faced by medical physicists. This approach included courses for graduates not associated to educational programs of Medical Physics (MP). Results: The implementation of the MPBE began in September 2014, with the electives of Radiation MP and Introduction to Nuclear Magnetic Resonance. The students of second year received an Introduction to MP. This initiative was validated by the departmental Methodological Workshop, which promoted the full implementation of the MPBE. Both postgraduated and undergraduate trainees participated in practices with our DICOM viewer system, a local prototype for photoplethysmography and a home-made interface for ROC analysis, built with MATLAB. All these tools were designed and constructed in previous RDI projects. The collaborative supervision of University’s researchers with clinical medical physicists will allow to overcome the limitations of residency in hospitals, to reduce the workload for clinical supervisors and develop appropriate educational activities. Conclusion: We demonstrated the feasibility of adaptable educational strategies, considering available resources. This provides an innovative way for prospective medical physicists, technologists and radiation oncologists. This strategy can be implemented in several regions

  10. Rice Dwarf Virus P2 Protein Hijacks Auxin Signaling by Directly Targeting the Rice OsIAA10 Protein, Enhancing Viral Infection and Disease Development.

    PubMed

    Jin, Lian; Qin, Qingqing; Wang, Yu; Pu, Yingying; Liu, Lifang; Wen, Xing; Ji, Shaoyi; Wu, Jianguo; Wei, Chunhong; Ding, Biao; Li, Yi

    2016-09-01

    The phytohormone auxin plays critical roles in regulating myriads of plant growth and developmental processes. Microbe infection can disturb auxin signaling resulting in defects in these processes, but the underlying mechanisms are poorly understood. Auxin signaling begins with perception of auxin by a transient co-receptor complex consisting of an F-box transport inhibitor response 1/auxin signaling F-box (TIR1/AFB) protein and an auxin/indole-3-acetic acid (Aux/IAA) protein. Auxin binding to the co-receptor triggers ubiquitination and 26S proteasome degradation of the Aux/IAA proteins, leading to subsequent events, including expression of auxin-responsive genes. Here we report that Rice dwarf virus (RDV), a devastating pathogen of rice, causes disease symptoms including dwarfing, increased tiller number and short crown roots in infected rice as a result of reduced sensitivity to auxin signaling. The RDV capsid protein P2 binds OsIAA10, blocking the interaction between OsIAA10 and OsTIR1 and inhibiting 26S proteasome-mediated OsIAA10 degradation. Transgenic rice plants overexpressing wild-type or a dominant-negative (degradation-resistant) mutant of OsIAA10 phenocopy RDV symptoms are more susceptible to RDV infection; however, knockdown of OsIAA10 enhances the resistance of rice to RDV infection. Our findings reveal a previously unknown mechanism of viral protein reprogramming of a key step in auxin signaling initiation that enhances viral infection and pathogenesis. PMID:27606959

  11. Rice Dwarf Virus P2 Protein Hijacks Auxin Signaling by Directly Targeting the Rice OsIAA10 Protein, Enhancing Viral Infection and Disease Development

    PubMed Central

    Jin, Lian; Qin, Qingqing; Wang, Yu; Pu, Yingying; Liu, Lifang; Wen, Xing; Ji, Shaoyi; Wu, Jianguo; Wei, Chunhong; Li, Yi

    2016-01-01

    The phytohormone auxin plays critical roles in regulating myriads of plant growth and developmental processes. Microbe infection can disturb auxin signaling resulting in defects in these processes, but the underlying mechanisms are poorly understood. Auxin signaling begins with perception of auxin by a transient co-receptor complex consisting of an F-box transport inhibitor response 1/auxin signaling F-box (TIR1/AFB) protein and an auxin/indole-3-acetic acid (Aux/IAA) protein. Auxin binding to the co-receptor triggers ubiquitination and 26S proteasome degradation of the Aux/IAA proteins, leading to subsequent events, including expression of auxin-responsive genes. Here we report that Rice dwarf virus (RDV), a devastating pathogen of rice, causes disease symptoms including dwarfing, increased tiller number and short crown roots in infected rice as a result of reduced sensitivity to auxin signaling. The RDV capsid protein P2 binds OsIAA10, blocking the interaction between OsIAA10 and OsTIR1 and inhibiting 26S proteasome-mediated OsIAA10 degradation. Transgenic rice plants overexpressing wild-type or a dominant-negative (degradation-resistant) mutant of OsIAA10 phenocopy RDV symptoms are more susceptible to RDV infection; however, knockdown of OsIAA10 enhances the resistance of rice to RDV infection. Our findings reveal a previously unknown mechanism of viral protein reprogramming of a key step in auxin signaling initiation that enhances viral infection and pathogenesis. PMID:27606959

  12. Insect-Inspired Self-Motion Estimation with Dense Flow Fields—An Adaptive Matched Filter Approach

    PubMed Central

    Strübbe, Simon; Stürzl, Wolfgang; Egelhaaf, Martin

    2015-01-01

    The control of self-motion is a basic, but complex task for both technical and biological systems. Various algorithms have been proposed that allow the estimation of self-motion from the optic flow on the eyes. We show that two apparently very different approaches to solve this task, one technically and one biologically inspired, can be transformed into each other under certain conditions. One estimator of self-motion is based on a matched filter approach; it has been developed to describe the function of motion sensitive cells in the fly brain. The other estimator, the Koenderink and van Doorn (KvD) algorithm, was derived analytically with a technical background. If the distances to the objects in the environment can be assumed to be known, the two estimators are linear and equivalent, but are expressed in different mathematical forms. However, for most situations it is unrealistic to assume that the distances are known. Therefore, the depth structure of the environment needs to be determined in parallel to the self-motion parameters and leads to a non-linear problem. It is shown that the standard least mean square approach that is used by the KvD algorithm leads to a biased estimator. We derive a modification of this algorithm in order to remove the bias and demonstrate its improved performance by means of numerical simulations. For self-motion estimation it is beneficial to have a spherical visual field, similar to many flying insects. We show that in this case the representation of the depth structure of the environment derived from the optic flow can be simplified. Based on this result, we develop an adaptive matched filter approach for systems with a nearly spherical visual field. Then only eight parameters about the environment have to be memorized and updated during self-motion. PMID:26308839

  13. Insect-Inspired Self-Motion Estimation with Dense Flow Fields--An Adaptive Matched Filter Approach.

    PubMed

    Strübbe, Simon; Stürzl, Wolfgang; Egelhaaf, Martin

    2015-01-01

    The control of self-motion is a basic, but complex task for both technical and biological systems. Various algorithms have been proposed that allow the estimation of self-motion from the optic flow on the eyes. We show that two apparently very different approaches to solve this task, one technically and one biologically inspired, can be transformed into each other under certain conditions. One estimator of self-motion is based on a matched filter approach; it has been developed to describe the function of motion sensitive cells in the fly brain. The other estimator, the Koenderink and van Doorn (KvD) algorithm, was derived analytically with a technical background. If the distances to the objects in the environment can be assumed to be known, the two estimators are linear and equivalent, but are expressed in different mathematical forms. However, for most situations it is unrealistic to assume that the distances are known. Therefore, the depth structure of the environment needs to be determined in parallel to the self-motion parameters and leads to a non-linear problem. It is shown that the standard least mean square approach that is used by the KvD algorithm leads to a biased estimator. We derive a modification of this algorithm in order to remove the bias and demonstrate its improved performance by means of numerical simulations. For self-motion estimation it is beneficial to have a spherical visual field, similar to many flying insects. We show that in this case the representation of the depth structure of the environment derived from the optic flow can be simplified. Based on this result, we develop an adaptive matched filter approach for systems with a nearly spherical visual field. Then only eight parameters about the environment have to be memorized and updated during self-motion.

  14. Motion adaptive patch-based low-rank approach for compressed sensing cardiac cine MRI.

    PubMed

    Yoon, Huisu; Kim, Kyung Sang; Kim, Daniel; Bresler, Yoram; Ye, Jong Chul

    2014-11-01

    One of the technical challenges in cine magnetic resonance imaging (MRI) is to reduce the acquisition time to enable the high spatio-temporal resolution imaging of a cardiac volume within a short scan time. Recently, compressed sensing approaches have been investigated extensively for highly accelerated cine MRI by exploiting transform domain sparsity using linear transforms such as wavelets, and Fourier. However, in cardiac cine imaging, the cardiac volume changes significantly between frames, and there often exist abrupt pixel value changes along time. In order to effectively sparsify such temporal variations, it is necessary to exploit temporal redundancy along motion trajectories. This paper introduces a novel patch-based reconstruction method to exploit geometric similarities in the spatio-temporal domain. In particular, we use a low rank constraint for similar patches along motion, based on the observation that rank structures are relatively less sensitive to global intensity changes, but make it easier to capture moving edges. A Nash equilibrium formulation with relaxation is employed to guarantee convergence. Experimental results show that the proposed algorithm clearly reconstructs important anatomical structures in cardiac cine image and provides improved image quality compared to existing state-of-the-art methods such as k-t FOCUSS, k-t SLR, and MASTeR.

  15. Multiple adaptations to polar and alpine environments within cyanobacteria: a phylogenomic and Bayesian approach

    PubMed Central

    Chrismas, Nathan A. M.; Anesio, Alexandre M.; Sánchez-Baracaldo, Patricia

    2015-01-01

    Cyanobacteria are major primary producers in the polar and alpine regions contributing significantly to nitrogen and carbon cycles in the cryosphere. Recent advancements in environmental sequencing techniques have revealed great molecular diversity of microorganisms in cold environments. However, there are no comprehensive phylogenetic analyses including the entire known diversity of cyanobacteria from these extreme environments. We present here a global phylogenetic analysis of cyanobacteria including an extensive dataset comprised of available small subunit (SSU) rRNA gene sequences of cyanobacteria from polar and high altitude environments. Furthermore, we used a large-scale multi-gene (135 proteins and 2 ribosomal RNAs) genome constraint including 57 cyanobacterial genomes. Our analyses produced the first phylogeny of cold cyanobacteria exhibiting robust deep branching relationships implementing a phylogenomic approach. We recovered several clades common to Arctic, Antarctic and alpine sites suggesting that the traits necessary for survival in the cold have been acquired by a range of different mechanisms in all major cyanobacteria lineages. Bayesian ancestral state reconstruction revealed that 20 clades each have common ancestors with high probabilities of being capable of surviving in cold environments. PMID:26528250

  16. Native Prairie Adaptive Management: a multi region adaptive approach to invasive plant management on Fish and Wildlife Service owned native prairies

    USGS Publications Warehouse

    Gannon, Jill J.; Shaffer, Terry L.; Moore, Clinton T.

    2013-01-01

    Much of the native prairie managed by the U.S. Fish and Wildlife Service (FWS) in the Prairie Pothole Region (PPR) of the northern Great Plains is extensively invaded by the introduced cool-season grasses, smooth brome (Bromus inermis) and Kentucky bluegrass (Poa pratensis). Management to suppress these invasive plants has had poor to inconsistent success. The central challenge to managers is selecting appropriate management actions in the face of biological and environmental uncertainties. In partnership with the FWS, the U.S. Geological Survey (USGS) developed an adaptive decision support framework to assist managers in selecting management actions under uncertainty and maximizing learning from management outcomes. This joint partnership is known as the Native Prairie Adaptive Management (NPAM) initiative. The NPAM decision framework is built around practical constraints faced by FWS refuge managers and includes identification of the management objective and strategies, analysis of uncertainty and construction of competing decision models, monitoring, and mechanisms for model feedback and decision selection. Nineteen FWS field stations, spanning four states of the PPR, have participated in the initiative. These FWS cooperators share a common management objective, available management strategies, and biological uncertainties. Though the scope is broad, the initiative interfaces with individual land managers who provide site-specific information and receive updated decision guidance that incorporates understanding gained from the collective experience of all cooperators. We describe the technical components of this approach, how the components integrate and inform each other, how data feedback from individual cooperators serves to reduce uncertainty across the whole region, and how a successful adaptive management project is coordinated and maintained on a large scale. During an initial scoping workshop, FWS cooperators developed a consensus management objective

  17. Organizational Adaptation and Higher Education.

    ERIC Educational Resources Information Center

    Cameron, Kim S.

    1984-01-01

    Organizational adaptation and types of adaptation needed in academe in the future are reviewed and major conceptual approaches to organizational adaptation are presented. The probable environment that institutions will face in the future that will require adaptation is discussed. (MLW)

  18. Adapting the medaka embryo assay to a high-throughput approach for developmental toxicity testing.

    PubMed

    Oxendine, Sharon L; Cowden, John; Hinton, David E; Padilla, Stephanie

    2006-09-01

    Chemical exposure during embryonic development may cause persistent effects, yet developmental toxicity data exist for very few chemicals. Current testing procedures are time consuming and costly, underlining the need for rapid and low cost screening strategies. While in vitro methods are useful for screening, these methods do not replicate all the intricacies of embryonic development and should ideally be complemented by an in vivo screening strategy. In this study, we modify a medaka fish embryo assay to meet the requirements of high-throughput, developmental toxicant testing in vivo. The Japanese medaka (Oryzias latipes) offers several advantages over traditional mammalian model systems, including economic husbandry, high fecundity, and rapid ex utero development. In most studies where fish eggs are exposed to a chemical, the exposure takes place in a common vessel, with many embryos being exposed to the same solution. This type of design is not amenable to high-throughput methodology, does not allow the investigator to follow the same embryo throughout gestation, and may confound statistical analysis of the results. Therefore, we developed a 96-well microtiter plate method to facilitate exposure of individual medaka embryos in single wells and compared this approach to the common vessel method using the industrial solvent dimethyl sulfoxide (DMSO) as the test compound. At lower DMSO concentrations (0% or 1%), the 96-well microtiter plate assay replicated results obtained using the common vessel exposure method. There was, however, increased lethality and decreased hatching rate in the bottle-reared embryos treated with the higher DMSO concentrations (5% or 10%). Because the embryos reared in the 96-well microtiter plates never showed increased adverse effects (as compared to the bottle-reared embryos) at any DMSO concentration, we conclude that the 96-well microtiter plate assay provides a rapid and efficient alternative for developmental toxicity screens that

  19. The adaptive function of tiger moth clicks against echolocating bats: an experimental and synthetic approach.

    PubMed

    Ratcliffe, John M; Fullard, James H

    2005-12-01

    We studied the efficiency and effects of the multiple sensory cues of tiger moths on echolocating bats. We used the northern long-eared bat, Myotis septentrionalis, a purported moth specialist that takes surface-bound prey (gleaning) and airborne prey (aerial hawking), and the dogbane tiger moth, Cycnia tenera, an eared species unpalatable to bats that possesses conspicuous colouration and sound-producing organs (tymbals). This is the first study to investigate the interaction of tiger moths and wild-caught bats under conditions mimicking those found in nature and to demand the use of both aerial hawking and gleaning strategies by bats. Further, it is the first to report spectrograms of the sounds produced by tiger moths while under aerial attack by echolocating bats. During both aerial hawking and gleaning trials, all muted C. tenera and perched intact C. tenera were attacked by M. septentrionalis, indicating that M. septentrionalis did not discriminate C. tenera from palatable moths based on potential echoic and/or non-auditory cues. Intact C. tenera were attacked significantly less often than muted C. tenera during aerial hawking attacks: tymbal clicks were therefore an effective deterrent in an aerial hawking context. During gleaning attacks, intact and muted C. tenera were always attacked and suffered similar mortality rates, suggesting that while handling prey this bat uses primarily chemical signals. Our results also show that C. tenera temporally matches the onset of click production to the ;approach phase' echolocation calls produced by aerial hawking attacking bats and that clicks themselves influence the echolocation behaviour of attacking bats. In the context of past research, these findings support the hypotheses that the clicks of arctiid moths are both an active defence (through echolocation disruption) and a reliable indicator of chemical defence against aerial-hawking bats. We suggest these signals are specialized for an aerial context.

  20. A Unified Approach to Adaptive Neural Control for Nonlinear Discrete-Time Systems With Nonlinear Dead-Zone Input.

    PubMed

    Liu, Yan-Jun; Gao, Ying; Tong, Shaocheng; Chen, C L Philip

    2016-01-01

    In this paper, an effective adaptive control approach is constructed to stabilize a class of nonlinear discrete-time systems, which contain unknown functions, unknown dead-zone input, and unknown control direction. Different from linear dead zone, the dead zone, in this paper, is a kind of nonlinear dead zone. To overcome the noncausal problem, which leads to the control scheme infeasible, the systems can be transformed into a m -step-ahead predictor. Due to nonlinear dead-zone appearance, the transformed predictor still contains the nonaffine function. In addition, it is assumed that the gain function of dead-zone input and the control direction are unknown. These conditions bring about the difficulties and the complicacy in the controller design. Thus, the implicit function theorem is applied to deal with nonaffine dead-zone appearance, the problem caused by the unknown control direction can be resolved through applying the discrete Nussbaum gain, and the neural networks are used to approximate the unknown function. Based on the Lyapunov theory, all the signals of the resulting closed-loop system are proved to be semiglobal uniformly ultimately bounded. Moreover, the tracking error is proved to be regulated to a small neighborhood around zero. The feasibility of the proposed approach is demonstrated by a simulation example.

  1. A Unified Approach to Adaptive Neural Control for Nonlinear Discrete-Time Systems With Nonlinear Dead-Zone Input.

    PubMed

    Liu, Yan-Jun; Gao, Ying; Tong, Shaocheng; Chen, C L Philip

    2016-01-01

    In this paper, an effective adaptive control approach is constructed to stabilize a class of nonlinear discrete-time systems, which contain unknown functions, unknown dead-zone input, and unknown control direction. Different from linear dead zone, the dead zone, in this paper, is a kind of nonlinear dead zone. To overcome the noncausal problem, which leads to the control scheme infeasible, the systems can be transformed into a m -step-ahead predictor. Due to nonlinear dead-zone appearance, the transformed predictor still contains the nonaffine function. In addition, it is assumed that the gain function of dead-zone input and the control direction are unknown. These conditions bring about the difficulties and the complicacy in the controller design. Thus, the implicit function theorem is applied to deal with nonaffine dead-zone appearance, the problem caused by the unknown control direction can be resolved through applying the discrete Nussbaum gain, and the neural networks are used to approximate the unknown function. Based on the Lyapunov theory, all the signals of the resulting closed-loop system are proved to be semiglobal uniformly ultimately bounded. Moreover, the tracking error is proved to be regulated to a small neighborhood around zero. The feasibility of the proposed approach is demonstrated by a simulation example. PMID:26353383

  2. Canalization of auxin flow by Aux/IAA-ARF-dependent feedback regulation of PIN polarity.

    PubMed

    Sauer, Michael; Balla, Jozef; Luschnig, Christian; Wisniewska, Justyna; Reinöhl, Vilém; Friml, Jirí; Benková, Eva

    2006-10-15

    Plant development is characterized by a profound ability to regenerate and form tissues with new axes of polarity. An unsolved question concerns how the position within a tissue and cues from neighboring cells are integrated to specify the polarity of individual cells. The canalization hypothesis proposes a feedback effect of the phytohormone auxin on the directionality of intercellular auxin flow as a means to polarize tissues. Here we identify a cellular and molecular mechanism for canalization. Local auxin application, wounding, or auxin accumulation during de novo organ formation lead to rearrangements in the subcellular polar localization of PIN auxin transport components. This auxin effect on PIN polarity is cell-specific, does not depend on PIN transcription, and involves the Aux/IAA-ARF (indole-3-acetic acid-auxin response factor) signaling pathway. Our data suggest that auxin acts as polarizing cue, which links individual cell polarity with tissue and organ polarity through control of PIN polar targeting. This feedback regulation provides a conceptual framework for polarization during multiple regenerative and patterning processes in plants.

  3. Canalization of auxin flow by Aux/IAA-ARF-dependent feedback regulation of PIN polarity.

    PubMed

    Sauer, Michael; Balla, Jozef; Luschnig, Christian; Wisniewska, Justyna; Reinöhl, Vilém; Friml, Jirí; Benková, Eva

    2006-10-15

    Plant development is characterized by a profound ability to regenerate and form tissues with new axes of polarity. An unsolved question concerns how the position within a tissue and cues from neighboring cells are integrated to specify the polarity of individual cells. The canalization hypothesis proposes a feedback effect of the phytohormone auxin on the directionality of intercellular auxin flow as a means to polarize tissues. Here we identify a cellular and molecular mechanism for canalization. Local auxin application, wounding, or auxin accumulation during de novo organ formation lead to rearrangements in the subcellular polar localization of PIN auxin transport components. This auxin effect on PIN polarity is cell-specific, does not depend on PIN transcription, and involves the Aux/IAA-ARF (indole-3-acetic acid-auxin response factor) signaling pathway. Our data suggest that auxin acts as polarizing cue, which links individual cell polarity with tissue and organ polarity through control of PIN polar targeting. This feedback regulation provides a conceptual framework for polarization during multiple regenerative and patterning processes in plants. PMID:17043314

  4. The IAA cosmic dust laboratory: Experimental scattering matrices of clay particles

    NASA Astrophysics Data System (ADS)

    Muñoz, O.; Moreno, F.; Guirado, D.; Ramos, J. L.; Volten, H.; Hovenier, J. W.

    2011-01-01

    We present the first results of measurements on solid particles performed at the Instituto de Astrofı´sica de Andalucı´a (IAA) cosmic dust laboratory located in Granada, Spain. The laboratory apparatus measures the complete scattering matrix as a function of the scattering angle of aerosol particles. The measurements can be performed at a wavelength ( λ) of 483, 488, 520, 568, or 647 nm in the scattering angle range from 3° to 177°. Results of special test experiments are presented which show that our experimental results for scattering matrices are not significantly contaminated by multiple scattering and that the sizes/shapes of the particles do not change during the measurements. Moreover, the measured scattering matrix for a sample of green clay particles is compared with measurements previously performed in the Amsterdam light scattering setup for the same sample. New measurements on a white clay sample at 488 and 647 nm are also presented. The apparatus is devoted to experimentally studying the angle dependence of scattering matrices of dust samples of astrophysical interest. Moreover, there is a great interest in similar studies of aerosols that can affect the radiative balance of the atmosphere of the Earth and other planets such as silicates, desert dust, volcanic ashes, and carbon soot particles.

  5. Validation of MIPAS IMK/IAA V5R_O3_224 ozone profiles

    NASA Astrophysics Data System (ADS)

    Laeng, A.; Grabowski, U.; von Clarmann, T.; Stiller, G.; Glatthor, N.; Höpfner, M.; Kellmann, S.; Kiefer, M.; Linden, A.; Lossow, S.; Sofieva, V.; Petropavlovskikh, I.; Hubert, D.; Bathgate, T.; Bernath, P.; Boone, C. D.; Clerbaux, C.; Coheur, P.; Damadeo, R.; Degenstein, D.; Frith, S.; Froidevaux, L.; Gille, J.; Hoppel, K.; McHugh, M.; Kasai, Y.; Lumpe, J.; Rapoe, N.; Toon, G.; Sano, T.; Suzuki, M.; Tamminen, J.; Urban, J.; Walker, K.; Weber, M.; Zawodny, J.

    2014-04-01

    We present the results of an extensive validation program of the most recent version of ozone vertical profiles retrieved with the IMK/IAA MIPAS research level 2 processor from version 5 spectral Level 1 data. The time period covered corresponds to the reduced spectral resolution period of the MIPAS instrument, i.e. January 2005-April 2012. The comparison with satellite instruments includes all post-2005 satellite limb and occultation sensors having measured the vertical profiles of tropospheric and stratospheric ozone: ACE-FTS, GOMOS, HALOE, HIRDLS, MLS, OSIRIS, POAM, SAGE II, SCIAMACHY, SMILES, and SMR. In addition, balloon-borne MkIV solar occultation measurements and groundbased Umkehr measurements have been included, as well as two nadir sensors: IASI and SBUV. For each reference dataset, bias determination and precision assessment are performed. Better agreement with reference instruments than for the previous data version, V5R_O3_220 (Laeng et al., 2013), is found: the known high bias around the ozone vmr peak is significantly reduced and the vertical resolution at 35 km has been improved. The agreement with limb and solar occultation reference instruments that have a known small bias vs. ozone sondes is within 7% in the lower and middle stratosphere and 5% in the upper troposphere. Around the ozone vmr peak, the agreement with most of satellite reference instruments is within 5%; this bias is as low as 3% for ACE-FTS, MLS, OSIRIS, POAM and SBUV.

  6. Dual adaptive statistical approach for quantitative noise reduction in photon-counting medical imaging: application to nuclear medicine images

    NASA Astrophysics Data System (ADS)

    Hannequin, Pascal Paul

    2015-06-01

    Noise reduction in photon-counting images remains challenging, especially at low count levels. We have developed an original procedure which associates two complementary filters using a Wiener-derived approach. This approach combines two statistically adaptive filters into a dual-weighted (DW) filter. The first one, a statistically weighted adaptive (SWA) filter, replaces the central pixel of a sliding window with a statistically weighted sum of its neighbors. The second one, a statistical and heuristic noise extraction (extended) (SHINE-Ext) filter, performs a discrete cosine transformation (DCT) using sliding blocks. Each block is reconstructed using its significant components which are selected using tests derived from multiple linear regression (MLR). The two filters are weighted according to Wiener theory. This approach has been validated using a numerical phantom and a real planar Jaszczak phantom. It has also been illustrated using planar bone scintigraphy and myocardial single-photon emission computed tomography (SPECT) data. Performances of filters have been tested using mean normalized absolute error (MNAE) between the filtered images and the reference noiseless or high-count images. Results show that the proposed filters quantitatively decrease the MNAE in the images and then increase the signal-to-noise Ratio (SNR). This allows one to work with lower count images. The SHINE-Ext filter is well suited to high-size images and low-variance areas. DW filtering is efficient for low-size images and in high-variance areas. The relative proportion of eliminated noise generally decreases when count level increases. In practice, SHINE filtering alone is recommended when pixel spacing is less than one-quarter of the effective resolution of the system and/or the size of the objects of interest. It can also be used when the practical interest of high frequencies is low. In any case, DW filtering will be preferable. The proposed filters have been applied to nuclear

  7. Automated registration of laser Doppler perfusion images by an adaptive correlation approach: application to focal cerebral ischemia in the rat.

    PubMed

    Riyamongkol, Panomkhawn; Zhao, Weizhao; Liu, Yitao; Belayev, Ludmila; Busto, Raul; Ginsberg, Myron D

    2002-12-31

    Hemodynamic changes are extremely important in analyzing responses from a brain subjected to a stimulus or treatment. The Laser Doppler technique has emerged as an important tool in neuroscience research. This non-invasive method scans a low-power laser beam in a raster pattern over a tissue surface to generate the time course of images in unit of relative flux changes. Laser Doppler imager (LDI) records cerebral perfusion not only in the temporal but also in the spatial domain. The traditional analysis of LD images has been focused on the region-of-interest (ROI) approach, in which the analytical accuracy in an experiment that necessitates a relative repositioning between the LDI and the scanned tissue area will be weakened due to the operator's subjective decision in data collecting. This report describes a robust image registration method designed to obviate this problem, which is based on the adaptive correlation approach. The assumption in mapping corresponding pixels in two images is to correlate the regions in which these pixels are centered. Based on this assumption, correlation coefficients are calculated between two regions by a method in which one region is moved around over the other in all possible combinations. To avoid ambiguity in distinguishing maximum correlation coefficients, an adaptive algorithm is adopted. Correspondences are then used to estimate the transformation by linear regression. We used a pair of phantom LD images to test this algorithm. A reliability test was also performed on each of the 15 sequential LD images derived from an actual experiment by imposing rotation and translation. The result shows that the calculated transformation parameters (rotation: theta =7.7+/-0.5 degrees; translation: Delta x =2.8+/-0.3, Deltaŷ=4.7+/-0.4) are very close to the prior-set parameters (rotation: theta=8 degrees; translation: Delta x=3, Delta y=5). This result indicates that this approach is a valuable adjunct to LD perfusion monitoring. An

  8. Application of stakeholder-based and modelling approaches for supporting robust adaptation decision making under future climatic uncertainty and changing urban-agricultural water demand

    NASA Astrophysics Data System (ADS)

    Bhave, Ajay; Dessai, Suraje; Conway, Declan; Stainforth, David

    2016-04-01

    Deep uncertainty in future climate change and socio-economic conditions necessitates the use of assess-risk-of-policy approaches over predict-then-act approaches for adaptation decision making. Robust Decision Making (RDM) approaches embody this principle and help evaluate the ability of adaptation options to satisfy stakeholder preferences under wide-ranging future conditions. This study involves the simultaneous application of two RDM approaches; qualitative and quantitative, in the Cauvery River Basin in Karnataka (population ~23 million), India. The study aims to (a) determine robust water resources adaptation options for the 2030s and 2050s and (b) compare the usefulness of a qualitative stakeholder-driven approach with a quantitative modelling approach. For developing a large set of future scenarios a combination of climate narratives and socio-economic narratives was used. Using structured expert elicitation with a group of climate experts in the Indian Summer Monsoon, climatic narratives were developed. Socio-economic narratives were developed to reflect potential future urban and agricultural water demand. In the qualitative RDM approach, a stakeholder workshop helped elicit key vulnerabilities, water resources adaptation options and performance criteria for evaluating options. During a second workshop, stakeholders discussed and evaluated adaptation options against the performance criteria for a large number of scenarios of climatic and socio-economic change in the basin. In the quantitative RDM approach, a Water Evaluation And Planning (WEAP) model was forced by precipitation and evapotranspiration data, coherent with the climatic narratives, together with water demand data based on socio-economic narratives. We find that compared to business-as-usual conditions options addressing urban water demand satisfy performance criteria across scenarios and provide co-benefits like energy savings and reduction in groundwater depletion, while options reducing

  9. Recognition of the folded conformation of plant hormone (auxin, IAA) conjugates with glutamic and aspartic acids and their amides

    NASA Astrophysics Data System (ADS)

    Antolić, S.; Kveder, M.; Klaić, B.; Magnus, V.; Kojić-Prodić, B.

    2001-01-01

    The molecular structure of the endogenous plant hormone (auxin) conjugate, N-(indol-3-ylacetyl)- L-glutamic acid, is deduced by comparison with N2-(indol-3-ylacetyl)glutamine (IAA-Gln), N2-(indol-3-ylacetyl)asparagine (IAA-Asn) and N-(indol-3-ylacetyl)- L-aspartic acid using X-ray structure analysis, 1H-NMR spectroscopy (NOE measurements) and molecular modelling. The significance of the overall molecular shape, and of the resulting amphiphilic properties, of the compounds studied are discussed in terms of possible implications for trafficking between cell compartments. Both in the solid state and in solution, the molecules are in the hair-pin (folded) conformation in which the side chain is folded over the indole ring. While extended conformations can be detected by molecular dynamics simulations, they are so short-lived that any major influence on the biological properties of the compounds studied is unlikely.

  10. Effects of IAA, IBA, NAA, and GA3 on Rooting and Morphological Features of Melissa officinalis L. Stem Cuttings

    PubMed Central

    Guney, Kerim

    2013-01-01

    This study analyzed the potential of producing Melissa officinalis L. using stem cuttings. Four different hormones (IAA, IBA, NAA, and GA3) were applied to the cuttings, with and without buds, in two doses (1000 mg/L and 5000 mg/L), and after 60 days, 10 morphological characteristics of newly generated plants were detected, and a statistical analysis was carried out. The results of the study show that the cuttings with at least one bud must be used in order to produce M. officinalis using stem cuttings. Even though the auxin group hormones (IAA, IBA, and NAA) do not have an apparent effect on rooting percentage, these hormones were detected to affect the morphological characteristics of the newly generated plants, especially root generation. GA3 application has a considerable effect on stem height. PMID:23818834

  11. Effects of IAA, IBA, NAA, and GA3 on rooting and morphological features of Melissa officinalis L. stem cuttings.

    PubMed

    Sevik, Hakan; Guney, Kerim

    2013-01-01

    This study analyzed the potential of producing Melissa officinalis L. using stem cuttings. Four different hormones (IAA, IBA, NAA, and GA3) were applied to the cuttings, with and without buds, in two doses (1000 mg/L and 5000 mg/L), and after 60 days, 10 morphological characteristics of newly generated plants were detected, and a statistical analysis was carried out. The results of the study show that the cuttings with at least one bud must be used in order to produce M. officinalis using stem cuttings. Even though the auxin group hormones (IAA, IBA, and NAA) do not have an apparent effect on rooting percentage, these hormones were detected to affect the morphological characteristics of the newly generated plants, especially root generation. GA3 application has a considerable effect on stem height. PMID:23818834

  12. Effects of IAA, IBA, NAA, and GA3 on rooting and morphological features of Melissa officinalis L. stem cuttings.

    PubMed

    Sevik, Hakan; Guney, Kerim

    2013-01-01

    This study analyzed the potential of producing Melissa officinalis L. using stem cuttings. Four different hormones (IAA, IBA, NAA, and GA3) were applied to the cuttings, with and without buds, in two doses (1000 mg/L and 5000 mg/L), and after 60 days, 10 morphological characteristics of newly generated plants were detected, and a statistical analysis was carried out. The results of the study show that the cuttings with at least one bud must be used in order to produce M. officinalis using stem cuttings. Even though the auxin group hormones (IAA, IBA, and NAA) do not have an apparent effect on rooting percentage, these hormones were detected to affect the morphological characteristics of the newly generated plants, especially root generation. GA3 application has a considerable effect on stem height.

  13. A fuzzy adaptive network approach to parameter estimation in cases where independent variables come from an exponential distribution

    NASA Astrophysics Data System (ADS)

    Dalkilic, Turkan Erbay; Apaydin, Aysen

    2009-11-01

    In a regression analysis, it is assumed that the observations come from a single class in a data cluster and the simple functional relationship between the dependent and independent variables can be expressed using the general model; Y=f(X)+[epsilon]. However; a data cluster may consist of a combination of observations that have different distributions that are derived from different clusters. When faced with issues of estimating a regression model for fuzzy inputs that have been derived from different distributions, this regression model has been termed the [`]switching regression model' and it is expressed with . Here li indicates the class number of each independent variable and p is indicative of the number of independent variables [J.R. Jang, ANFIS: Adaptive-network-based fuzzy inference system, IEEE Transaction on Systems, Man and Cybernetics 23 (3) (1993) 665-685; M. Michel, Fuzzy clustering and switching regression models using ambiguity and distance rejects, Fuzzy Sets and Systems 122 (2001) 363-399; E.Q. Richard, A new approach to estimating switching regressions, Journal of the American Statistical Association 67 (338) (1972) 306-310]. In this study, adaptive networks have been used to construct a model that has been formed by gathering obtained models. There are methods that suggest the class numbers of independent variables heuristically. Alternatively, in defining the optimal class number of independent variables, the use of suggested validity criterion for fuzzy clustering has been aimed. In the case that independent variables have an exponential distribution, an algorithm has been suggested for defining the unknown parameter of the switching regression model and for obtaining the estimated values after obtaining an optimal membership function, which is suitable for exponential distribution.

  14. Siderophore production and the evolution of investment in a public good: An adaptive dynamics approach to kin selection.

    PubMed

    Lee, William; van Baalen, Minus; Jansen, Vincent A A

    2016-01-01

    Like many other bacteria, Pseudomonas aeruginosa sequesters iron from the environment through the secretion, and subsequent uptake, of iron-binding molecules. As these molecules can be taken up by other bacteria in the population than those who secreted them, this is a form of cooperation through a public good. Traditionally, this problem has been studied by comparing the relative fitnesses of siderophore-producing and non-producing strains, but this gives no information about the fate of strains that do produce intermediate amounts of siderophores. Here, we investigate theoretically how the amount invested in this form of cooperation evolves. We use a mechanistic description of the laboratory protocols used in experimental evolution studies to describe the competition and cooperation of the bacteria. From this dynamical model we derive the fitness following the adaptive dynamics method. The results show how selection is driven by local siderophore production and local competition. Because siderophore production reduces the growth rate, local competition decreases with the degree of relatedness (which is a dynamical variable in our model). Our model is not restricted to the analysis of small phenotypic differences and allows for theoretical exploration of the effects of large phenotypic differences between cooperators and cheats. We predict that an intermediate ESS level of cooperation (molecule production) should exist. The adaptive dynamics approach allows us to assess evolutionary stability, which is often not possible in other kin-selection models. We found that selection can lead to an intermediate strategy which in our model is always evolutionarily stable, yet can allow invasion of strategies that are much more cooperative. Our model describes the evolution of a public good in the context of the ecology of the microorganism, which allows us to relate the extent of production of the public good to the details of the interactions. PMID:26471069

  15. Glacial Lake Outburst Flood Risk in Himachal Pradesh, India: An Integrative and Anticipatory Approach to Inform Adaptation Planning

    NASA Astrophysics Data System (ADS)

    Allen, Simon; Linsbauer, Andreas; Huggel, Christian; Singh Randhawa, Surjeet

    2016-04-01

    Most research concerning the hazard from glacial lake outburst floods (GLOFs) has focused on the threat from lakes that have formed over the past century, and which continue to expand rapidly in response to recent warming of the climate system. However, attention is shifting towards the anticipation of future hazard and risk associated with new lakes that will develop as glaciers continue to retreat and dramatically different landscapes are uncovered. Nowhere will this threat be more pronounced than in the Himalaya, where the majority of the world's glaciers are found, and where the dynamics of nature interact closely with livelihoods and anthropogenic resources. Using the Indian Himalayan state of Himachal Pradesh (HP) as a case study, we combine a suite of GIS-based approaches to: 1)Implement a large-scale automated GLOF risk assessment within an integrative climate risk framework that recognizes both physical and socio-economic determining factors. 2)Expand the assessment beyond the current situation, to provide early anticipation of emerging GLOF hazard as new lakes form in response to further retreat of the Himalayan glaciers. Results clearly demonstrate a significant future increase in relative GLOF hazard levels across most Thesils of HP (administrative units), as the overall potential for GLOFs being triggered from mass movement of ice and rock avalanches increases, and as new GLOF paths affect additional land areas. Across most Thesils, the simulated increase in GLOF frequency is an order of magnitude larger than the simulated increase in GLOF affected area, as paths from newly formed glacial lakes generally tend to converge downstream within existing flood channels. In the Thesil of Kullu for example, we demonstrate a 7-fold increase in the probability of GLOF occurrence, and a 3-fold increase in the area affected by potential GLOF paths. In those situations where potential GLOFs from new lakes will flow primarily along existing flood paths, any

  16. Uptake and incorporation of labeled tryptophan isomers into IAA in the jsR sub 1 mutant of Lemna gibba

    SciTech Connect

    Baldi, B.G.; Maher, B.R.; Cohen, J.D. )

    1989-04-01

    Analyses of the IAA-overproducing mutant of Lemna have been initiated in order to study in vivo biosynthesis of IAA. Using radiolabelled tryptophan isomers prepared from commercial sources of {sup 14}C-D,L tryptophan by chiral separation kinetics of uptake of L and D tryptophan were determined for sterile cultures of individual jsR{sub 1} four-frond colonies. Over a 24 h period, about 50% of the radioactivity from {sup 14}C-L-TRP in media, or about 25% from {sup 14}C-D-TRP, was found in the plant tissue. Maximal rates of uptake were seen in the first six hors for both isomers. Endogenous levels of tryptophan determined in jsR{sub 1} as measures of pool sizes in vivo show 5 to 10 ug/g FW total tryptophan with less than 1% in the D isomer form. Information on uptake and endogenous pool sizes of tryptophan isomers is being used for feeding of stable isotope labeled tryptophan ({sup 13}C, {sup 14}N) to jsR{sub 1} at physiological levels. Analyses of incorporation of label into IAA using GC-MS and high resolution mass spectrometry are currently underway.

  17. Stimulatory effect of cytokinins and interaction with IAA on the release of lateral buds of pea plants from apical dominance.

    PubMed

    Li, Chunjian; Bangerth, Fritz

    2003-09-01

    Lateral buds of pea plants can be released from apical dominance and even be transformed into dominant shoots when repeatedly treated with synthetic exogenous cytokinins (CKs). The mechanism of the effect of CKs, however, is not clear. The results in this work showed that the stimulatory effects of CKs on the growth of lateral buds and the increase in their fresh weights in pea plants depended on the structure and concentration of the CKs used. The effect of N-(2-chloro-4-pyridyl)-N'-phenylurea (CPPU) was stronger than that of 6-benzylaminopurine (6-BA). Indoleacetic acid (IAA) concentration in shoot, IAA export out of the treated apex and basipetal transport in stems were markedly increased after the application of CPPU or 6-BA to the apex or the second node of pea plant. This increase was positively correlated with the increased concentration of the applied CKs. These results suggest that the increased IAA synthesis and export induced by CKs application might be responsible for the growth of lateral shoots in intact pea plants. PMID:14593807

  18. Perturbation of Auxin Homeostasis by Overexpression of Wild-Type IAA15 Results in Impaired Stem Cell Differentiation and Gravitropism in Roots

    PubMed Central

    Yan, Da-Wei; Wang, Jing; Yuan, Ting-Ting; Hong, Li-Wei; Gao, Xiang; Lu, Ying-Tang

    2013-01-01

    Aux/IAAs interact with auxin response factors (ARFs) to repress their transcriptional activity in the auxin signaling pathway. Previous studies have focused on gain-of-function mutations of domain II and little is known about whether the expression level of wild-type Aux/IAAs can modulate auxin homeostasis. Here we examined the perturbation of auxin homeostasis by ectopic expression of wild-type IAA15. Root gravitropism and stem cell differentiation were also analyzed. The transgenic lines were less sensitive to exogenous auxin and exhibited low-auxin phenotypes including failures in gravity response and defects in stem cell differentiation. Overexpression lines also showed an increase in auxin concentration and reduced polar auxin transport. These results demonstrate that an alteration in the expression of wild-type IAA15 can disrupt auxin homeostasis. PMID:23472140

  19. Validation of MIPAS IMK/IAA V5R_O3_224 ozone profiles

    NASA Astrophysics Data System (ADS)

    Laeng, A.; Grabowski, U.; von Clarmann, T.; Stiller, G.; Glatthor, N.; Höpfner, M.; Kellmann, S.; Kiefer, M.; Linden, A.; Lossow, S.; Sofieva, V.; Petropavlovskikh, I.; Hubert, D.; Bathgate, T.; Bernath, P.; Boone, C. D.; Clerbaux, C.; Coheur, P.; Damadeo, R.; Degenstein, D.; Frith, S.; Froidevaux, L.; Gille, J.; Hoppel, K.; McHugh, M.; Kasai, Y.; Lumpe, J.; Rahpoe, N.; Toon, G.; Sano, T.; Suzuki, M.; Tamminen, J.; Urban, J.; Walker, K.; Weber, M.; Zawodny, J.

    2014-11-01

    We present the results of an extensive validation program of the most recent version of ozone vertical profiles retrieved with the IMK/IAA (Institute for Meteorology and Climate Research/Instituto de Astrofísica de Andalucía) MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) research level 2 processor from version 5 spectral level 1 data. The time period covered corresponds to the reduced spectral resolution period of the MIPAS instrument, i.e., January 2005-April 2012. The comparison with satellite instruments includes all post-2005 satellite limb and occultation sensors that have measured the vertical profiles of tropospheric and stratospheric ozone: ACE-FTS, GOMOS, HALOE, HIRDLS, MLS, OSIRIS, POAM, SAGE II, SCIAMACHY, SMILES, and SMR. In addition, balloon-borne MkIV solar occultation measurements and ground-based Umkehr measurements have been included, as well as two nadir sensors: IASI and SBUV. For each reference data set, bias determination and precision assessment are performed. Better agreement with reference instruments than for the previous data version, V5R_O3_220 (Laeng et al., 2014), is found: the known high bias around the ozone vmr (volume mixing ratio) peak is significantly reduced and the vertical resolution at 35 km has been improved. The agreement with limb and solar occultation reference instruments that have a known small bias vs. ozonesondes is within 7% in the lower and middle stratosphere and 5% in the upper troposphere. Around the ozone vmr peak, the agreement with most of the satellite reference instruments is within 5%; this bias is as low as 3% for ACE-FTS, MLS, OSIRIS, POAM and SBUV.

  20. Adaptive Correlation Space Adjusted Open-Loop Tracking Approach for Vehicle Positioning with Global Navigation Satellite System in Urban Areas.

    PubMed

    Ruan, Hang; Li, Jian; Zhang, Lei; Long, Teng

    2015-08-28

    For vehicle positioning with Global Navigation Satellite System (GNSS) in urban areas, open-loop tracking shows better performance because of its high sensitivity and superior robustness against multipath. However, no previous study has focused on the effects of the code search grid size on the code phase measurement accuracy of open-loop tracking. Traditional open-loop tracking methods are performed by the batch correlators with fixed correlation space. The code search grid size, which is the correlation space, is a constant empirical value and the code phase measuring accuracy will be largely degraded due to the improper grid size, especially when the signal carrier-to-noise density ratio (C/N₀) varies. In this study, the Adaptive Correlation Space Adjusted Open-Loop Tracking Approach (ACSA-OLTA) is proposed to improve the code phase measurement dependent pseudo range accuracy. In ACSA-OLTA, the correlation space is adjusted according to the signal C/N₀. The novel Equivalent Weighted Pseudo Range Error (EWPRE) is raised to obtain the optimal code search grid sizes for different C/N₀. The code phase measuring errors of different measurement calculation methods are analyzed for the first time. The measurement calculation strategy of ACSA-OLTA is derived from the analysis to further improve the accuracy but reduce the correlator consumption. Performance simulation and real tests confirm that the pseudo range and positioning accuracy of ASCA-OLTA are better than the traditional open-loop tracking methods in the usual scenarios of urban area.

  1. Tissue-specific defense and thermo-adaptive mechanisms of soybean seedlings under heat stress revealed by proteomic approach.

    PubMed

    Ahsan, Nagib; Donnart, Tifenn; Nouri, Mohammad-Zaman; Komatsu, Setsuko

    2010-08-01

    A comparative proteomic approach was employed to explore tissue-specific protein expression patterns in soybean seedlings under heat stress. The changes in the protein expression profiles of soybean seedling leaves, stems, and roots were analyzed after exposure to high temperatures. A total of 54, 35, and 61 differentially expressed proteins were identified from heat-treated leaves, stems, and roots, respectively. Differentially expressed heat shock proteins (HSPs) and proteins involved in antioxidant defense were mostly up-regulated, whereas proteins associated with photosynthesis, secondary metabolism, and amino acid and protein biosynthesis were down-regulated in response to heat stress. A group of proteins, specifically low molecular weight HSPs and HSP70, were up-regulated and expressed in a similar manner in all tissues. Proteomic analysis indicated that the responses of HSP70, CPN-60 beta, and ChsHSP were tissue specific, and this observation was validated by immunoblot analysis. The heat-responsive sHSPs were not induced by other stresses such as cold and hydrogen peroxide. Taken together, these results suggest that to cope with heat stress soybean seedlings operate tissue-specific defenses and adaptive mechanisms, whereas a common defense mechanism associated with the induction of several HSPs was employed in all three tissues. In addition, tissue-specific proteins may play a crucial role in defending each type of tissues against thermal stress.

  2. Adaptive approach for on-board impedance parameters and voltage estimation of lithium-ion batteries in electric vehicles

    NASA Astrophysics Data System (ADS)

    Farmann, Alexander; Waag, Wladislaw; Sauer, Dirk Uwe

    2015-12-01

    Robust algorithms using reduced order equivalent circuit model (ECM) for an accurate and reliable estimation of battery states in various applications become more popular. In this study, a novel adaptive, self-learning heuristic algorithm for on-board impedance parameters and voltage estimation of lithium-ion batteries (LIBs) in electric vehicles is introduced. The presented approach is verified using LIBs with different composition of chemistries (NMC/C, NMC/LTO, LFP/C) at different aging states. An impedance-based reduced order ECM incorporating ohmic resistance and a combination of a constant phase element and a resistance (so-called ZARC-element) is employed. Existing algorithms in vehicles are much more limited in the complexity of the ECMs. The algorithm is validated using seven day real vehicle data with high temperature variation including very low temperatures (from -20 °C to +30 °C) at different Depth-of-Discharges (DoDs). Two possibilities to approximate both ZARC-elements with finite number of RC-elements on-board are shown and the results of the voltage estimation are compared. Moreover, the current dependence of the charge-transfer resistance is considered by employing Butler-Volmer equation. Achieved results indicate that both models yield almost the same grade of accuracy.

  3. Adaptive approach for variable noise suppression on laser-induced breakdown spectroscopy responses using stationary wavelet transform.

    PubMed

    Schlenke, Jan; Hildebrand, Lars; Moros, Javier; Laserna, J Javier

    2012-11-19

    Spectral signals are often corrupted by noise during their acquisition and transmission. Signal processing refers to a variety of operations that can be carried out on measurements in order to enhance the quality of information. In this sense, signal denoising is used to reduce noise distortions while keeping alterations of the important signal features to a minimum. The minimization of noise is a highly critical task since, in many cases, there is no prior knowledge of the signal or of the noise. In the context of denoising, wavelet transformation has become a valuable tool. The present paper proposes a noise reduction technique for suppressing noise in laser-induced breakdown spectroscopy (LIBS) signals using wavelet transform. An extension of the Donoho's scheme, which uses a redundant form of wavelet transformation and an adaptive threshold estimation method, is suggested. Capabilities and results achieved on denoising processes of artificial signals and actual spectroscopic data, both corrupted by noise with changing intensities, are presented. In order to better consolidate the gains so far achieved by the proposed strategy, a comparison with alternative approaches, as well as with traditional techniques, is also made.

  4. ELICITED EXPERT PERCEPTIONS FOR CLIMATE CHANGE RISKS AND ADAPTATION IN AGRICULTURE AND FOOD PRODUCTION THROUGH MENTAL MODELS APPROACH

    NASA Astrophysics Data System (ADS)

    Suda, Eiko; Kubota, Hiromi; Baba, Kenshi; Hijioka, Yasuaki; Takahashi, Kiyoshi; Hanasaki, Naota

    Impacts of climate change have become obvious in agriculture and food production in Japan these days, and researches to adapt to their risks have been conducted as a key effort to cope with the climate change. Numerous scientific findings on climate change impacts have been presented so far; however, prospective risks to be adapted to and their management in the context of individual on-site situations have not been investigated in detail. The structure of climate change risks and their management vary depending on geographical and social features in the regions where the adaptation options should be applied; therefore, a practical adaptation strategy should consider actual on-site situations. This study intended to clarify climate change risks to be adapted to in the Japanese agricultural sector, and factors to be considered in adaptation options, for encouragement of decision-making on adaptation implementation in the field. Semi-structured individual interviews have been conducted with 9 multidisciplinary experts engaging in climate change impacts research in agricultural production, economics, engineering, policy, and so on. Based on the results of the interviews, and the latest literatures available for risk assessment and adaptation, an expert mental model including their perceptions which cover the process from climate change impacts assessment to adaptation has been developed. The prospective risks, adaptation options, and issues to be examined to progress the development of practical and effective adaptation options and to support individual or social decision-making, have been shown on the developed expert mental model. It is the basic information for developing social communication and stakeholders cooperations in climate change adaptation strategies in agriculture and food production in Japan.

  5. Adaptive management

    USGS Publications Warehouse

    Allen, Craig R.; Garmestani, Ahjond S.

    2015-01-01

    Adaptive management is an approach to natural resource management that emphasizes learning through management where knowledge is incomplete, and when, despite inherent uncertainty, managers and policymakers must act. Unlike a traditional trial and error approach, adaptive management has explicit structure, including a careful elucidation of goals, identification of alternative management objectives and hypotheses of causation, and procedures for the collection of data followed by evaluation and reiteration. The process is iterative, and serves to reduce uncertainty, build knowledge and improve management over time in a goal-oriented and structured process.

  6. Cellulosomics, a Gene-Centric Approach to Investigating the Intraspecific Diversity and Adaptation of Ruminococcus flavefaciens within the Rumen

    PubMed Central

    Brulc, Jennifer M.; Yeoman, Carl J.; Wilson, Melissa K.; Berg Miller, Margret E.; Jeraldo, Patricio; Jindou, Sadanari; Goldenfeld, Nigel; Flint, Harry J.; Lamed, Raphael; Borovok, Ilya; Vodovnik, Maša; Nelson, Karen E.; Bayer, Edward A.; White, Bryan A.

    2011-01-01

    to be examined and represents a gene-centric approach to investigating the intraspecific adaptation of an important specialist population. PMID:22043282

  7. Being Mindful about the Assessment of Culture: A Cultural Analysis of Culturally Adapted Acceptance-Based Behavior Therapy Approaches

    ERIC Educational Resources Information Center

    La Roche, Martin; Lustig, Kara

    2013-01-01

    In this article we review a wide range of cultural adaptations of acceptance-based behavior therapies (ABBT) from a cultural perspective. Consistent with the cultural match model, we argue that psychotherapeutic cultural adaptations are more effective as the cultural characteristics of patients are matched to the cultural characteristics of the…

  8. Adaptive Correlation Space Adjusted Open-Loop Tracking Approach for Vehicle Positioning with Global Navigation Satellite System in Urban Areas

    PubMed Central

    Ruan, Hang; Li, Jian; Zhang, Lei; Long, Teng

    2015-01-01

    For vehicle positioning with Global Navigation Satellite System (GNSS) in urban areas, open-loop tracking shows better performance because of its high sensitivity and superior robustness against multipath. However, no previous study has focused on the effects of the code search grid size on the code phase measurement accuracy of open-loop tracking. Traditional open-loop tracking methods are performed by the batch correlators with fixed correlation space. The code search grid size, which is the correlation space, is a constant empirical value and the code phase measuring accuracy will be largely degraded due to the improper grid size, especially when the signal carrier-to-noise density ratio (C/N0) varies. In this study, the Adaptive Correlation Space Adjusted Open-Loop Tracking Approach (ACSA-OLTA) is proposed to improve the code phase measurement dependent pseudo range accuracy. In ACSA-OLTA, the correlation space is adjusted according to the signal C/N0. The novel Equivalent Weighted Pseudo Range Error (EWPRE) is raised to obtain the optimal code search grid sizes for different C/N0. The code phase measuring errors of different measurement calculation methods are analyzed for the first time. The measurement calculation strategy of ACSA-OLTA is derived from the analysis to further improve the accuracy but reduce the correlator consumption. Performance simulation and real tests confirm that the pseudo range and positioning accuracy of ASCA-OLTA are better than the traditional open-loop tracking methods in the usual scenarios of urban area. PMID:26343683

  9. The Swedish Interplanetary Society (1950-1969) and the formation of IAF and IAA

    NASA Astrophysics Data System (ADS)

    Ingemar Skoog, A.

    2011-06-01

    With a growing interest for rocket technology and space travel after WW II a number of new "space societies" were formed in the period 1948-1951 in addition to the ones already existing in Germany, the UK and the US since before WW II. Soon came the need for a common international platform for exchange of information and experience, and the concept of an international federation of astronautical societies emerged. Sweden was one of the 8 countries to sign the original declaration to create an International Astronautical Federation on October 2, 1950 in Paris at the 1st International Astronautical Congress. The Swedish Society for Space Research (Svenska Sällskapet för Rymdforskning) was formed a few days after the historical event in Paris. The name was soon to be changed to the Swedish Interplanetary Society (Svenska Interplanetariska Sällskapet, SIS). Sweden was one of the 10 countries to sign the IAF foundation in 1951 in London and in the following year the first Constitution of IAF in Stuttgart. The SIS quickly grow to a membership of several hundred persons and its membership in IAF promoted an intensive exchange of journals, and the annual participation at the IAC gave growth to start study projects on spacecraft and sounding rockets, and the publication of astronautical journals in Swedish. In 1957 the first Swede was elected vice-president of IAF. Not too long after the IAF foundation the idea of an international body of distinguished individuals emerged, in addition to the body of "member societies" (IAF). Upon the initiative of Theodor von Karman, Eugen Sänger and Andrew Haley the IAF council approval of an International Academy of Astronautical was given on August 15, 1960 during the 11th IAC in Stockholm. This IAC in Stockholm gave a large publicity to space research and astronautics in Sweden, and put the activities of the SIS in the focus of the general public. This paper presents the Swedish involvement in the foundation of IAF and IAA. It also

  10. Where is the faith? Using a CBPR approach to propose adaptations to an evidence-based HIV prevention intervention for adolescents in African American faith settings.

    PubMed

    Lightfoot, Alexandra F; Taggart, Tamara; Woods-Jaeger, Briana A; Riggins, Linda; Jackson, Melvin R; Eng, Eugenia

    2014-08-01

    African American adolescents are at increased risk for HIV/AIDS. Using a community-based participatory research approach, we engaged three black churches in adapting an evidence-based HIV prevention intervention, Focus on Youth (FOY)+ImPACT, for faith settings. To identify potential adaptations to increase FOY's relevance, utility, and efficacy for faith settings, we conducted eight focus groups pre- and post-intervention. Recommendations for maintaining FOY's core elements and enhancing its cultural authenticity include the following: incorporating faith tools, building pastor capacity, strengthening parent-child communication skills, and expanding social support for parents and youth. Engaging faith communities in adapting and implementing evidence-based HIV prevention programs could reduce HIV/AIDS disparities.

  11. L1 Adaptive Control Augmentation System with Application to the X-29 Lateral/Directional Dynamics: A Multi-Input Multi-Output Approach

    NASA Technical Reports Server (NTRS)

    Griffin, Brian Joseph; Burken, John J.; Xargay, Enric

    2010-01-01

    This paper presents an L(sub 1) adaptive control augmentation system design for multi-input multi-output nonlinear systems in the presence of unmatched uncertainties which may exhibit significant cross-coupling effects. A piecewise continuous adaptive law is adopted and extended for applicability to multi-input multi-output systems that explicitly compensates for dynamic cross-coupling. In addition, explicit use of high-fidelity actuator models are added to the L1 architecture to reduce uncertainties in the system. The L(sub 1) multi-input multi-output adaptive control architecture is applied to the X-29 lateral/directional dynamics and results are evaluated against a similar single-input single-output design approach.

  12. The studies on the toxicity mechanism of environmentally hazardous natural (IAA) and synthetic (NAA) auxin--The experiments on model Arabidopsis thaliana and rat liver plasma membranes.

    PubMed

    Hąc-Wydro, Katarzyna; Flasiński, Michał

    2015-06-01

    This paper concerns the studies towards membrane-damage effect of two auxins: indole-3-acetic acid - IAA and 1-naphthaleneacetic acid - NAA on plant (Arabidopsis thaliana) and animal (rat liver) model membranes. The foregoing auxins are plant growth regulators widely used in agriculture to control the quality of the crop. However, their accumulation in the environment makes them hazardous for the living organisms. The aim of our investigations was to compare the effect of natural (IAA) vs. synthetic (NAA) auxin on the organization of plant and animal model membranes and find a possible correlation between membrane-disturbing effect of these compounds and their toxicity. The collected data evidenced that auxins cause destabilization of membranes, decrease their condensation and weakens interactions of molecules. The alterations in the morphology of model systems were also noticed. The foregoing effects of auxins are concentration-dependent and additionally NAA was found to act on animal vs. plant membranes more selectively than IAA. Interestingly, both IAA and NAA induce the strongest disordering in model lipid system at the concentration, which is frequently reported as toxic to animal and plants. Based on the above findings it was proposed that membrane-damage effect induced by IAA and NAA may be important from the point of view of the mechanism of toxicity of these compounds and cannot be ignored in further investigations in this area.

  13. Integrating climate change mitigation, adaptation, communication and education strategies in Matanzas Province, Cuba: A Citizen Science Approach

    NASA Astrophysics Data System (ADS)

    Rodriguez Bueno, R. A.; Byrne, J. M.

    2015-12-01

    The Environment Service Center of Matanzas (ESCM), Cuba and the University of Lethbridge are collaborating on the development of climate mitigation and adaptation programs in Matanzas province. Tourism is the largest industry in Matanzas. Protecting that industry means protecting coastal zones and conservation areas of value to tourism. These same areas are critical to protecting the landscape from global environmental change: enhanced tropical cyclones, flooding, drought and a range of other environmental change impacts. Byrne (2014) adapted a multidisciplinary methodology for climate adaptation capacity definition for the population of Nicaragua. A wide array of adaptive capacity skills and resources were integrated with agricultural crop modeling to define regions of the country where adaptive capacity development were weakest and should be improved. In Matanzas province, we are developing a series of multidisciplinary mitigation and adaptation programs that builds social science and science knowledge to expand capacity within the ESCM and the provincial population. We will be exploring increased risk due to combined watershed and tropical cyclone flooding, stresses on crops, and defining a range of possibilities in shifting from fossil fuels to renewable energy. The program will build ongoing interactions with thousands of Matanzas citizens through site visits carried out by numerous Cuban and visiting students participating in a four-month education semester with a number of Lethbridge and Matanzas faculty. These visits will also provide local citizens with better access to web-based interactions. We will evaluate mitigation and adaptive capacities in three municipalities and some rural areas across the province. Furthermore, we will explore better ways and means to communicate between the research and conservation staff and the larger population of the province.

  14. Building adaptive capacity to cope with increasing vulnerability due to climatic change in Africa A new approach

    NASA Astrophysics Data System (ADS)

    Twomlow, Steve; Mugabe, Francis T.; Mwale, Moses; Delve, Robert; Nanja, Durton; Carberry, Peter; Howden, Mark

    The world community faces many risks from climate change, with most scenarios indicating higher temperatures and more erratic rainfall in Africa. Predictions for southern Africa suggest a general decrease in total seasonal rainfall, accompanied by more frequent in-season dry spells that will significantly impact crop and livestock production, and hence economic growth in the region. The hardest hit will be the rural poor in the drier areas, where crop failure due to drought is already common and chronic food emergencies afflict the region in most years. Lessons can be learnt on how the rural poor currently cope with the vagaries of climate and these can be used to help them adapt their current production systems to the future threats of further climate change. But this assumes the institutions that work towards the economic empowerment of the rural poor have the requisite skills to understand their current coping strategies and how adaptation can be facilitated. A new initiative led by Midlands State University and the Zambian Meteorological Office proposes that improving the ability of institutions that train the ‘Future Change Agents’, who will subsequently support smallholder communities in adapting their agricultural practices to current climate variability, is the first step in building adaptive capacity to cope with future climate change. The capacity of African scientists, regional organizations and decision-makers in dealing with the issues of climate change and adaptation will be enhanced on a continuing basis, and the impacts of their agricultural development programs improved.

  15. A unique in vivo experimental approach reveals metabolic adaptation of the probiotic Propionibacterium freudenreichii to the colon environment

    PubMed Central

    2013-01-01

    Background Propionibacterium freudenreichii is a food grade bacterium consumed both in cheeses and in probiotic preparations. Its promising probiotic potential, relying largely on the active release of beneficial metabolites within the gut as well as the expression of key surface proteins involved in immunomodulation, deserves to be explored more deeply. Adaptation to the colon environment is requisite for the active release of propionibacterial beneficial metabolites and constitutes a bottleneck for metabolic activity in vivo. Mechanisms allowing P. freudenreichii to adapt to digestive stresses have been only studied in vitro so far. Our aim was therefore to study P. freudenreichii metabolic adaptation to intra-colonic conditions in situ. Results We maintained a pure culture of the type strain P. freudenreichii CIRM BIA 1, contained in a dialysis bag, within the colon of vigilant piglets during 24 hours. A transcriptomic analysis compared gene expression to identify the metabolic pathways induced by this environment, versus control cultures maintained in spent culture medium. We observed drastic changes in the catabolism of sugars and amino-acids. Glycolysis, the Wood-Werkman cycle and the oxidative phosphorylation pathways were down-regulated but induction of specific carbohydrate catabolisms and alternative pathways were induced to produce NADH, NADPH, ATP and precursors (utilizing of propanediol, gluconate, lactate, purine and pyrimidine and amino-acids). Genes involved in stress response were down-regulated and genes specifically expressed during cell division were induced, suggesting that P. freudenreichii adapted its metabolism to the conditions encountered in the colon. Conclusions This study constitutes the first molecular demonstration of P. freudenreichii activity and physiological adaptation in vivo within the colon. Our data are likely specific to our pig microbiota composition but opens an avenue towards understanding probiotic action within the gut

  16. An Ecological Approach to Promoting Early Adolescent Mental Health and Social Adaptation: Family-Centered Intervention in Public Middle Schools

    ERIC Educational Resources Information Center

    Stormshak, Elizabeth A.; Connell, Arin M.; Veronneau, Marie-Helene; Myers, Michael W.; Dishion, Thomas J.; Kavanagh, Kathryn; Caruthers, Allison S.

    2011-01-01

    This study examined the impact of the Family Check-Up (FCU) and linked intervention services on reducing health-risk behaviors and promoting social adaptation among middle school youth. A total of 593 students and their families were randomly assigned to receive either the intervention or middle school services as usual. Forty-two percent of…

  17. A Road Map Towards High pH Adaptability: Phenomic and Genomic Approaches to Azalea Breeding (Rhododendron sp.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A research grant from the Azalea Society of America has enabled us to collect and begin evaluating diverse Rhododendron viscosum germplasm to identify genetic and phenotypic variation for pH adaptability. During the Spring of 2014, we developed novel, in vitro screening methods for Rhododendron to ...

  18. Providing Adaptation and Guidance for Design Learning by Problem Solving: The Design Planning Approach in DomoSim-TPC Environment

    ERIC Educational Resources Information Center

    Redondo, Miguel A.; Bravo, Crescencio; Ortega, Manuel; Verdejo, M. Felisa

    2007-01-01

    Experimental learning environments based on simulation usually require monitoring and adaptation to the actions the users carry out. Some systems provide this functionality, but they do so in a way which is static or cannot be applied to problem solving tasks. In response to this problem, we propose a method based on the use of intermediate…

  19. Exploring the Role of Mechanotransduction Activation and Adaptation Kinetics in Hair Cell Filtering Using a Hodgkin-Huxley Approach

    NASA Astrophysics Data System (ADS)

    Wells, Gregg B.; Ricci, Anthony J.

    2011-11-01

    In the auditory system, mechanotransduction occurs in the hair cell sensory hair bundle and is the first major step in the translation of mechanical energy into electrical. Tonotopic variations in the activation kinetics of this process are posited to provide a low pass filter to the input. An adaptation process, also associated with mechanotransduction, is postulated to provide a high pass filter to the input in a tonotopic manner. Together a bandpass filter is created at the hair cell input. Corresponding mechanical components to both activation and adaptation are also suggested to be involved in generating cochlear amplification. A paradox to this story is that hair cells where the mechanotransduction properties are most robust possess an intrinsic electrical resonance mechanism proposed to account for all required tuning and amplification. A simple Hodgkin-Huxley type model is presented to attempt to determine the role of the activation and adaptation kinetics in further tuning hair cells that exhibit electrical resonance. Results further support that steady state mechanotransduction properties are critical for setting the resting potential of the hair cell while the kinetics of activation and adaptation are important for sharpening tuning around the characteristic frequency of the hair cell.

  20. Effects of an Adapted Physical Education Teaching Model on Special Educator Teaching Approaches for Students with Low Incidence Disabilities

    ERIC Educational Resources Information Center

    Laughlin, Michael K.

    2013-01-01

    The purpose of this study was to examine the effects of a training package, which consisted of the Flex Grid Teaching Model along with adapted physical education consultation, on special education teacher instruction of functional motor skill acquisition instruction to secondary students with low incidence disabilities. Special education teachers…

  1. Adapting CEF-Descriptors for Rating Purposes: Validation by a Combined Rater Training and Scale Revision Approach

    ERIC Educational Resources Information Center

    Harsch, Claudia; Martin, Guido

    2012-01-01

    We explore how a local rating scale can be based on the Common European Framework CEF-proficiency scales. As part of the scale validation (Alderson, 1991; Lumley, 2002), we examine which adaptations are needed to turn CEF-proficiency descriptors into a rating scale for a local context, and to establish a practicable method to revise the initial…

  2. Adapting Phonological Awareness Interventions for Children with Down Syndrome Based on the Behavioral Phenotype: A Promising Approach?

    ERIC Educational Resources Information Center

    Lemons, Christopher J.; King, Seth A.; Davidson, Kimberly A.; Puranik, Cynthia S.; Fulmer, Deborah; Mrachko, Alicia A.; Partanen, Jane; Al Otaiba, Stephanie; Fidler, Deborah J.

    2015-01-01

    Many children with Down syndrome demonstrate deficits in phonological awareness, a prerequisite to learning to read in an alphabetic language. The purpose of this study was to determine whether adapting a commercially available phonological awareness program to better align with characteristics associated with the behavioral phenotype of Down…

  3. Adaptive Strategies and Person-Environment Fit among Functionally Limited Older Adults Aging in Place: A Mixed Methods Approach.

    PubMed

    Lien, Laura L; Steggell, Carmen D; Iwarsson, Susanne

    2015-09-23

    Older adults prefer to age in place, necessitating a match between person and environment, or person-environment (P-E) fit. In occupational therapy practice, home modifications can support independence, but more knowledge is needed to optimize interventions targeting the housing situation of older adults. In response, this study aimed to explore the accessibility and usability of the home environment to further understand adaptive environmental behaviors. Mixed methods data were collected using objective and perceived indicators of P-E fit among 12 older adults living in community-dwelling housing. Quantitative data described objective P-E fit in terms of accessibility, while qualitative data explored perceived P-E fit in terms of usability. While accessibility problems were prevalent, participants' perceptions of usability revealed a range of adaptive environmental behaviors employed to meet functional needs. A closer examination of the P-E interaction suggests that objective accessibility does not always stipulate perceived usability, which appears to be malleable with age, self-perception, and functional competency. Findings stress the importance of evaluating both objective and perceived indicators of P-E fit to provide housing interventions that support independence. Further exploration of adaptive processes in older age may serve to deepen our understanding of both P-E fit frameworks and theoretical models of aging well.

  4. A social ecological approach to investigating relationships between housing and adaptive functioning for persons with serious mental illness.

    PubMed

    Kloos, Bret; Shah, Seema

    2009-12-01

    This paper seeks to advance mental health-housing research regarding which factors of housing and neighborhood environments are critical for adaptive functioning, health, and recovery for persons with serious mental illness (SMI). Housing and neighborhood environments are particularly important for persons with SMI because of the prevalence of poor housing conditions among this population. Most mental health-housing research has been limited by a focus on problems in environments and functioning. The paper seeks to expand the mental health-housing research agenda to consider protective factors that promote community integration and adaptive functioning. We provide an account of how social ecology theory transformed a research program, from examining individual risk factors to investigating the functioning of persons in the contexts of their housing and neighborhood experiences. The resulting housing environment framework-physical aspects of housing and neighborhoods, social environment of neighborhoods, and interpersonal relationships tied to housing-allows for identification of opportunities for health promotion and facilitation of participation in community-based settings. This program of research draws upon several methods to understand the social experience of persons with SMI living in community settings-survey research, qualitative interviews, Geographic Information Systems, participatory research, and visual ethnography. In this paper, we present how social ecology theory was instrumental in the development of new housing environment measures, the selection of appropriate research methods, and framing research questions that are building a new empirical base of knowledge about promoting adaptive functioning, health, and recovery for persons with SMI living in community settings.

  5. Adaptive Strategies and Person-Environment Fit among Functionally Limited Older Adults Aging in Place: A Mixed Methods Approach

    PubMed Central

    Lien, Laura L.; Steggell, Carmen D.; Iwarsson, Susanne

    2015-01-01

    Older adults prefer to age in place, necessitating a match between person and environment, or person-environment (P-E) fit. In occupational therapy practice, home modifications can support independence, but more knowledge is needed to optimize interventions targeting the housing situation of older adults. In response, this study aimed to explore the accessibility and usability of the home environment to further understand adaptive environmental behaviors. Mixed methods data were collected using objective and perceived indicators of P-E fit among 12 older adults living in community-dwelling housing. Quantitative data described objective P-E fit in terms of accessibility, while qualitative data explored perceived P-E fit in terms of usability. While accessibility problems were prevalent, participants’ perceptions of usability revealed a range of adaptive environmental behaviors employed to meet functional needs. A closer examination of the P-E interaction suggests that objective accessibility does not always stipulate perceived usability, which appears to be malleable with age, self-perception, and functional competency. Findings stress the importance of evaluating both objective and perceived indicators of P-E fit to provide housing interventions that support independence. Further exploration of adaptive processes in older age may serve to deepen our understanding of both P-E fit frameworks and theoretical models of aging well. PMID:26404352

  6. The Impact of Reclassification from Division II to DI-AA and from Division I-AA to I-A on NCAA Member Institutions from 1993 to 2003

    ERIC Educational Resources Information Center

    Frieder, Laura L., Comp.; Fulks, Daniel L., Comp.

    2007-01-01

    Recent years have seen a number of National Collegiate Athletic Association (NCAA) Division II institutions seeking reclassification to Division I-AA and Division I-AA institutions moving to Division I-A. Yet, other schools that seem like natural candidates to reclassify have resisted. The purpose of this study is to investigate the impact of the…

  7. Modeling the Internet of Things, Self-Organizing and Other Complex Adaptive Communication Networks: A Cognitive Agent-Based Computing Approach

    PubMed Central

    2016-01-01

    Background Computer Networks have a tendency to grow at an unprecedented scale. Modern networks involve not only computers but also a wide variety of other interconnected devices ranging from mobile phones to other household items fitted with sensors. This vision of the "Internet of Things" (IoT) implies an inherent difficulty in modeling problems. Purpose It is practically impossible to implement and test all scenarios for large-scale and complex adaptive communication networks as part of Complex Adaptive Communication Networks and Environments (CACOONS). The goal of this study is to explore the use of Agent-based Modeling as part of the Cognitive Agent-based Computing (CABC) framework to model a Complex communication network problem. Method We use Exploratory Agent-based Modeling (EABM), as part of the CABC framework, to develop an autonomous multi-agent architecture for managing carbon footprint in a corporate network. To evaluate the application of complexity in practical scenarios, we have also introduced a company-defined computer usage policy. Results The conducted experiments demonstrated two important results: Primarily CABC-based modeling approach such as using Agent-based Modeling can be an effective approach to modeling complex problems in the domain of IoT. Secondly, the specific problem of managing the Carbon footprint can be solved using a multiagent system approach. PMID:26812235

  8. Adapted Physical Education Service Approaches and the Effects on the Perceived Efficacy Beliefs of General Physical Education Teachers

    ERIC Educational Resources Information Center

    Umhoefer, Donna L.; Vargas, Tiffanye M.; Beyer, Robbi

    2015-01-01

    The purpose of this study was to determine what effect the type of APE service approach had on GPE teachers' efficacy when working with students with disabilities. The three approaches of APE service delivery chosen for the study were (a) consultation, (b) itinerant, and (c) collaborative. Results indicate significant differences between levels of…

  9. Experimental adaptive Bayesian tomography

    NASA Astrophysics Data System (ADS)

    Kravtsov, K. S.; Straupe, S. S.; Radchenko, I. V.; Houlsby, N. M. T.; Huszár, F.; Kulik, S. P.

    2013-06-01

    We report an experimental realization of an adaptive quantum state tomography protocol. Our method takes advantage of a Bayesian approach to statistical inference and is naturally tailored for adaptive strategies. For pure states, we observe close to N-1 scaling of infidelity with overall number of registered events, while the best nonadaptive protocols allow for N-1/2 scaling only. Experiments are performed for polarization qubits, but the approach is readily adapted to any dimension.

  10. Developing predictive approaches to characterize adaptive responses of the reproductive endocrine axis to aromatase inhibition: II. Computational modeling.

    PubMed

    Breen, Miyuki; Villeneuve, Daniel L; Ankley, Gerald T; Bencic, David C; Breen, Michael S; Watanabe, Karen H; Lloyd, Alun L; Conolly, Rory B

    2013-06-01

    Endocrine-disrupting chemicals can affect reproduction and development in humans and wildlife. We developed a computational model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course (DRTC) behaviors for endocrine effects of the aromatase inhibitor, fadrozole (FAD). The model describes adaptive responses to endocrine stress involving regulated secretion of a generic gonadotropin (LH/FSH) from the hypothalamic-pituitary complex. For model development, we used plasma 17β-estradiol (E2) concentrations and ovarian cytochrome P450 (CYP) 19A aromatase mRNA data from two time-course experiments, each of which included both an exposure and a depuration phase, and plasma E2 data from a third 4-day study. Model parameters were estimated using E2 concentrations for 0, 0.5, and 3 µg/l FAD exposure concentrations, and good fits to these data were obtained. The model accurately predicted CYP19A mRNA fold changes for controls and three FAD doses (0, 0.5, and 3 µg/l) and plasma E2 dose response from the 4-day study. Comparing the model-predicted DRTC with experimental data provided insight into how the feedback control mechanisms in the HPG axis mediate these changes: specifically, adaptive changes in plasma E2 levels occurring during exposure and "overshoot" occurring postexposure. This study demonstrates the value of mechanistic modeling to examine and predict dynamic behaviors in perturbed systems. As this work progresses, we will obtain a refined understanding of how adaptive responses within the vertebrate HPG axis affect DRTC behaviors for aromatase inhibitors and other types of endocrine-active chemicals and apply that knowledge in support of risk assessments.

  11. A Controls-CFD Approach for Estimation of Concentration from a Moving Aerial Source: Advantages of a Finite Volume-TVD implementation with Guidance-Based Grid Adaptation

    NASA Astrophysics Data System (ADS)

    Egorova, Tatiana; Gatsonis, Nikolaos A.; Demetriou, Michael A.

    2013-11-01

    In this work the process of gas release into the atmosphere by a moving aerial source is simulated and estimated using a sensing aerial vehicle (SAV). The process is modeled with atmospheric advection diffusion equation, which is solved by the finite volume method (FVM). Advective fluxes are constrained using total variation diminishing (TVD) approach. The estimator provides on-line estimates of concentration field and proximity of the source. The guidance of the SAV is dictated by the performance of the estimator. To further improve the estimation algorithm from the computational prospective, the grid is adapted dynamically through local refinement and coarsening. The adaptation algorithm uses the current sensor position as a center of refinement, with the areas further away from the SAV being covered by a coarse grid. This leads to the time varying state matrix of the estimator and the variation depends on the SAV motion. Advantages of the adaptive FVM-TVD implementation are illustrated on the examples of estimator performance for different source trajectories.

  12. Genome-wide analysis of the auxin-responsive transcriptome downstream of iaa1 and its expression analysis reveal the diversity and complexity of auxin-regulated gene expression.

    PubMed

    Lee, Dong Ju; Park, Jong Wha; Lee, Han Woo; Kim, Jungmook

    2009-01-01

    The AUXIN RESPONSE FACTORs (ARFs) and the Aux/IAA proteins regulate various auxin responses through auxin perception mediated by the F-box proteins TIR1/AFBs. ARFs are transcription factors that modulate expression of auxin response genes and are negatively regulated by the Aux/IAA proteins. To gain insight into the regulatory mechanisms of Aux/IAA-ARF action at the genome level, the transcriptome regulated downstream of iaa1, a stabilized IAA1 mutant protein, was identified using dexamethasone (DEX)-controlled nuclear translocation of iaa1 during the auxin response. The expression of the iaa1-regulated auxin-responsive genes selected from microarray data was analysed with RNA-gel blot analysis and it was shown that auxin-regulated expression of these genes was significantly inhibited by DEX treatment. While cycloheximide-inducible expression of a majority of these genes was also DEX-suppressible, expression of some genes could not be suppressed by treatment with DEX. Expression analysis in a variety of arf mutant backgrounds suggested that all iaa1-regulated auxin-response genes examined are controlled by ARFs to different extents and that the same ARF protein can regulate the expression of these genes in response to auxin in a positive or a negative manner. However, arf mutations did not affect auxin-mediated down-regulation, indicating that ARFs might not play a critical role in down-regulation. The decrease in auxin-responsive gene expression in arf7 arf19 mutants was more severe than that of tir1/afb quadruple mutants. These results show the diversity and complexity of mechanisms of Aux/IAA-ARF- and auxin-regulated gene expression. These data also provide the opportunity for functional analysis of genes mediating the auxin-response downstream of Aux/IAA-ARFs.

  13. Efficient Consistency Achievement of Federated Identity and Access Management Based on a Novel Self-Adaptable Approach

    NASA Astrophysics Data System (ADS)

    Cha, Shi-Cho; Chang, Hsiang-Meng

    Federated identity and access management (FIAM) systems enable a user to access services provided by various organizations seamlessly. In FIAM systems, service providers normally stipulate that their users show assertions issued by allied parties to use their services as well as determine user privileges based on attributes in the assertions. However, the integrity of the attributes is important under certain circumstances. In such a circumstance, all released assertions should reflect modifications made to user attributes. Despite the ability to adopt conventional certification revocation technologies, including CRL or OCSP, to revoke an assertion and request the corresponding user to obtain a new assertion, re-issuing an entirely new assertion if only one attribute, such as user location or other environmental information, is changed would be inefficient. Therefore, this work presents a self-adaptive framework to achieve consistency in federated identity and access management systems (SAFIAM). In SAFIAM, an identity provider (IdP), which authenticates users and provides user attributes, should monitor access probabilities according to user attributes. The IdP can then adopt the most efficient means of ensuring data integrity of attributes based on related access probabilities. While Internet-based services emerge daily that have various access probabilities with respect to their user attributes, the proposed self-adaptive framework significantly contributes to efforts to streamline the use of FIAM systems.

  14. How much can history constrain adaptive evolution? A real-time evolutionary approach of inversion polymorphisms in Drosophila subobscura.

    PubMed

    Fragata, I; Lopes-Cunha, M; Bárbaro, M; Kellen, B; Lima, M; Santos, M A; Faria, G S; Santos, M; Matos, M; Simões, P

    2014-12-01

    Chromosomal inversions are present in a wide range of animals and plants, having an important role in adaptation and speciation. Although empirical evidence of their adaptive value is abundant, the role of different processes underlying evolution of chromosomal polymorphisms is not fully understood. History and selection are likely to shape inversion polymorphism variation to an extent yet largely unknown. Here, we perform a real-time evolution study addressing the role of historical constraints and selection in the evolution of these polymorphisms. We founded laboratory populations of Drosophila subobscura derived from three locations along the European cline and followed the evolutionary dynamics of inversion polymorphisms throughout the first 40 generations. At the beginning, populations were highly differentiated and remained so throughout generations. We report evidence of positive selection for some inversions, variable between foundations. Signs of negative selection were more frequent, in particular for most cold-climate standard inversions across the three foundations. We found that previously observed convergence at the phenotypic level in these populations was not associated with convergence in inversion frequencies. In conclusion, our study shows that selection has shaped the evolutionary dynamics of inversion frequencies, but doing so within the constraints imposed by previous history. Both history and selection are therefore fundamental to predict the evolutionary potential of different populations to respond to global environmental changes.

  15. Knockout of GH3 genes in the moss Physcomitrella patens leads to increased IAA levels at elevated temperature and in darkness.

    PubMed

    Mittag, Jennifer; Gabrielyan, Anastasia; Ludwig-Müller, Jutta

    2015-12-01

    Two proteins of the GRETCHEN HAGEN3 (GH3) family of acyl acid amido synthetases from the moss Physcomitrella patens conjugate indole-3-acetic acid (IAA) to a series of amino acids. The possible function of altered auxin levels in the moss in response to two different growth perturbations, elevated temperatures and darkness, was analyzed using a) the recently described double knockout lines in both P. patens GH3 genes (GH3-doKO) and b) a previously characterized line harboring an auxin-inducible soybean GH3 promoter::reporter fused to β-glucuronidase (G1-GUS). The GUS activity as marker of the auxin response increased at higher temperatures and after cultivation in the darkness for a period of up to four weeks. Generally, the double knockout plants grew more slowly than the wild type (WT). The altered growth conditions influenced the phenotypes of the double knockout lines differently from that of WT moss. Higher temperatures negatively affected GH3-doKO plants compared to WT which was shown by stronger loss of chlorophyll. On the other hand, a positive effect was found on the concentrations of free IAA which increased at 28 °C in the GH3-doKO lines compared to WT plants. A different factor, namely darkness vs. a light/dark cycle caused the adverse phenotype concerning chlorophyll concentrations. Mutant moss plants showed higher chlorophyll concentrations than WT and these correlated with higher free IAA in the plant population that was classified as green. Our data show that growth perturbations result in higher free IAA levels in the GH3-doKO mutants, but in one case - growth in darkness - the mutants could cope better with the condition, whereas at elevated temperatures the mutants were more sensitive than WT. Thus, GH3 function in P. patens WT could lie in the regulation of IAA concentrations under unfavorable environmental conditions.

  16. Multi-approaches analysis reveals local adaptation in the emmer wheat (Triticum dicoccoides) at macro- but not micro-geographical scale.

    PubMed

    Volis, Sergei; Ormanbekova, Danara; Yermekbayev, Kanat; Song, Minshu; Shulgina, Irina

    2015-01-01

    Detecting local adaptation and its spatial scale is one of the most important questions of evolutionary biology. However, recognition of the effect of local selection can be challenging when there is considerable environmental variation across the distance at the whole species range. We analyzed patterns of local adaptation in emmer wheat, Triticum dicoccoides, at two spatial scales, small (inter-population distance less than one km) and large (inter-population distance more than 50 km) using several approaches. Plants originating from four distinct habitats at two geographic scales (cold edge, arid edge and two topographically dissimilar core locations) were reciprocally transplanted and their success over time was measured as 1) lifetime fitness in a year of planting, and 2) population growth four years after planting. In addition, we analyzed molecular (SSR) and quantitative trait variation and calculated the QST/FST ratio. No home advantage was detected at the small spatial scale. At the large spatial scale, home advantage was detected for the core population and the cold edge population in the year of introduction via measuring life-time plant performance. However, superior performance of the arid edge population in its own environment was evident only after several generations via measuring experimental population growth rate through genotyping with SSRs allowing counting the number of plants and seeds per introduced genotype per site. These results highlight the importance of multi-generation surveys of population growth rate in local adaptation testing. Despite predominant self-fertilization of T. dicoccoides and the associated high degree of structuring of genetic variation, the results of the QST - FST comparison were in general agreement with the pattern of local adaptation at the two spatial scales detected by reciprocal transplanting.

  17. Multi-approaches analysis reveals local adaptation in the emmer wheat (Triticum dicoccoides) at macro- but not micro-geographical scale.

    PubMed

    Volis, Sergei; Ormanbekova, Danara; Yermekbayev, Kanat; Song, Minshu; Shulgina, Irina

    2015-01-01

    Detecting local adaptation and its spatial scale is one of the most important questions of evolutionary biology. However, recognition of the effect of local selection can be challenging when there is considerable environmental variation across the distance at the whole species range. We analyzed patterns of local adaptation in emmer wheat, Triticum dicoccoides, at two spatial scales, small (inter-population distance less than one km) and large (inter-population distance more than 50 km) using several approaches. Plants originating from four distinct habitats at two geographic scales (cold edge, arid edge and two topographically dissimilar core locations) were reciprocally transplanted and their success over time was measured as 1) lifetime fitness in a year of planting, and 2) population growth four years after planting. In addition, we analyzed molecular (SSR) and quantitative trait variation and calculated the QST/FST ratio. No home advantage was detected at the small spatial scale. At the large spatial scale, home advantage was detected for the core population and the cold edge population in the year of introduction via measuring life-time plant performance. However, superior performance of the arid edge population in its own environment was evident only after several generations via measuring experimental population growth rate through genotyping with SSRs allowing counting the number of plants and seeds per introduced genotype per site. These results highlight the importance of multi-generation surveys of population growth rate in local adaptation testing. Despite predominant self-fertilization of T. dicoccoides and the associated high degree of structuring of genetic variation, the results of the QST - FST comparison were in general agreement with the pattern of local adaptation at the two spatial scales detected by reciprocal transplanting. PMID:25793512

  18. The model adaptive space shrinkage (MASS) approach: a new method for simultaneous variable selection and outlier detection based on model population analysis.

    PubMed

    Wen, Ming; Deng, Bai-Chuan; Cao, Dong-Sheng; Yun, Yong-Huan; Yang, Rui-Han; Lu, Hong-Mei; Liang, Yi-Zeng

    2016-10-01

    Variable selection and outlier detection are important processes in chemical modeling. Usually, they affect each other. Their performing orders also strongly affect the modeling results. Currently, many studies perform these processes separately and in different orders. In this study, we examined the interaction between outliers and variables and compared the modeling procedures performed with different orders of variable selection and outlier detection. Because the order of outlier detection and variable selection can affect the interpretation of the model, it is difficult to decide which order is preferable when the predictabilities (prediction error) of the different orders are relatively close. To address this problem, a simultaneous variable selection and outlier detection approach called Model Adaptive Space Shrinkage (MASS) was developed. This proposed approach is based on model population analysis (MPA). Through weighted binary matrix sampling (WBMS) from model space, a large number of partial least square (PLS) regression models were built, and the elite parts of the models were selected to statistically reassign the weight of each variable and sample. Then, the whole process was repeated until the weights of the variables and samples converged. Finally, MASS adaptively found a high performance model which consisted of the optimized variable subset and sample subset. The combination of these two subsets could be considered as the cleaned dataset used for chemical modeling. In the proposed approach, the problem of the order of variable selection and outlier detection is avoided. One near infrared spectroscopy (NIR) dataset and one quantitative structure-activity relationship (QSAR) dataset were used to test this approach. The result demonstrated that MASS is a useful method for data cleaning before building a predictive model. PMID:27435388

  19. Investigation of Adaptive-threshold Approaches for Determining Area-Time Integrals from Satellite Infrared Data to Estimate Convective Rain Volumes

    NASA Technical Reports Server (NTRS)

    Smith, Paul L.; VonderHaar, Thomas H.

    1996-01-01

    The principal goal of this project is to establish relationships that would allow application of area-time integral (ATI) calculations based upon satellite data to estimate rainfall volumes. The research is being carried out as a collaborative effort between the two participating organizations, with the satellite data analysis to determine values for the ATIs being done primarily by the STC-METSAT scientists and the associated radar data analysis to determine the 'ground-truth' rainfall estimates being done primarily at the South Dakota School of Mines and Technology (SDSM&T). Synthesis of the two separate kinds of data and investigation of the resulting rainfall-versus-ATI relationships is then carried out jointly. The research has been pursued using two different approaches, which for convenience can be designated as the 'fixed-threshold approach' and the 'adaptive-threshold approach'. In the former, an attempt is made to determine a single temperature threshold in the satellite infrared data that would yield ATI values for identifiable cloud clusters which are closely related to the corresponding rainfall amounts as determined by radar. Work on the second, or 'adaptive-threshold', approach for determining the satellite ATI values has explored two avenues: (1) attempt involved choosing IR thresholds to match the satellite ATI values with ones separately calculated from the radar data on a case basis; and (2) an attempt involved a striaghtforward screening analysis to determine the (fixed) offset that would lead to the strongest correlation and lowest standard error of estimate in the relationship between the satellite ATI values and the corresponding rainfall volumes.

  20. The model adaptive space shrinkage (MASS) approach: a new method for simultaneous variable selection and outlier detection based on model population analysis.

    PubMed

    Wen, Ming; Deng, Bai-Chuan; Cao, Dong-Sheng; Yun, Yong-Huan; Yang, Rui-Han; Lu, Hong-Mei; Liang, Yi-Zeng

    2016-10-01

    Variable selection and outlier detection are important processes in chemical modeling. Usually, they affect each other. Their performing orders also strongly affect the modeling results. Currently, many studies perform these processes separately and in different orders. In this study, we examined the interaction between outliers and variables and compared the modeling procedures performed with different orders of variable selection and outlier detection. Because the order of outlier detection and variable selection can affect the interpretation of the model, it is difficult to decide which order is preferable when the predictabilities (prediction error) of the different orders are relatively close. To address this problem, a simultaneous variable selection and outlier detection approach called Model Adaptive Space Shrinkage (MASS) was developed. This proposed approach is based on model population analysis (MPA). Through weighted binary matrix sampling (WBMS) from model space, a large number of partial least square (PLS) regression models were built, and the elite parts of the models were selected to statistically reassign the weight of each variable and sample. Then, the whole process was repeated until the weights of the variables and samples converged. Finally, MASS adaptively found a high performance model which consisted of the optimized variable subset and sample subset. The combination of these two subsets could be considered as the cleaned dataset used for chemical modeling. In the proposed approach, the problem of the order of variable selection and outlier detection is avoided. One near infrared spectroscopy (NIR) dataset and one quantitative structure-activity relationship (QSAR) dataset were used to test this approach. The result demonstrated that MASS is a useful method for data cleaning before building a predictive model.