Indirect learning control for nonlinear dynamical systems

NASA Technical Reports Server (NTRS)

Ryu, Yeong Soon; Longman, Richard W.

1993-01-01

In a previous paper, learning control algorithms were developed based on adaptive control ideas for linear time variant systems. The learning control methods were shown to have certain advantages over their adaptive control counterparts, such as the ability to produce zero tracking error in time varying systems, and the ability to eliminate repetitive disturbances. In recent years, certain adaptive control algorithms have been developed for multi-body dynamic systems such as robots, with global guaranteed convergence to zero tracking error for the nonlinear system euations. In this paper we study the relationship between such adaptive control methods designed for this specific class of nonlinear systems, and the learning control problem for such systems, seeking to converge to zero tracking error in following a specific command repeatedly, starting from the same initial conditions each time. The extension of these methods from the adaptive control problem to the learning control problem is seen to be trivial. The advantages and disadvantages of using learning control based on such adaptive control concepts for nonlinear systems, and the use of other currently available learning control algorithms are discussed.

Observer-based adaptive backstepping control for fractional order systems with input saturation.

PubMed

Sheng, Dian; Wei, Yiheng; Cheng, Songsong; Wang, Yong

2017-07-03

An observer-based fractional order anti-saturation adaptive backstepping control scheme is proposed for incommensurate fractional order systems with input saturation and partial measurable state in this paper. On the basis of stability analysis, a novel state observer is established first since the only information we could acquire is the system output. In order to compensate the saturation, a series of virtual signals are generated via the construction of fractional order auxiliary system. Afterwards, the controller design is carried out in accordance with the adaptive backstepping control method by introduction of the indirect Lyapunov method. To highlight the effectiveness of the proposed control scheme, simulation examples are demonstrated at last. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

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.

Neural controller for adaptive movements with unforeseen payloads.

PubMed

Kuperstein, M; Wang, J

1990-01-01

A theory and computer simulation of a neural controller that learns to move and position a link carrying an unforeseen payload accurately are presented. The neural controller learns adaptive dynamic control from its own experience. It does not use information about link mass, link length, or direction of gravity, and it uses only indirect uncalibrated information about payload and actuator limits. Its average positioning accuracy across a large range of payloads after learning is 3% of the positioning range. This neural controller can be used as a basis for coordinating any number of sensory inputs with limbs of any number of joints. The feedforward nature of control allows parallel implementation in real time across multiple joints.

Hybrid adaptive ascent flight control for a flexible launch vehicle

NASA Astrophysics Data System (ADS)

Lefevre, Brian D.

For the purpose of maintaining dynamic stability and improving guidance command tracking performance under off-nominal flight conditions, a hybrid adaptive control scheme is selected and modified for use as a launch vehicle flight controller. This architecture merges a model reference adaptive approach, which utilizes both direct and indirect adaptive elements, with a classical dynamic inversion controller. This structure is chosen for a number of reasons: the properties of the reference model can be easily adjusted to tune the desired handling qualities of the spacecraft, the indirect adaptive element (which consists of an online parameter identification algorithm) continually refines the estimates of the evolving characteristic parameters utilized in the dynamic inversion, and the direct adaptive element (which consists of a neural network) augments the linear feedback signal to compensate for any nonlinearities in the vehicle dynamics. The combination of these elements enables the control system to retain the nonlinear capabilities of an adaptive network while relying heavily on the linear portion of the feedback signal to dictate the dynamic response under most operating conditions. To begin the analysis, the ascent dynamics of a launch vehicle with a single 1st stage rocket motor (typical of the Ares 1 spacecraft) are characterized. The dynamics are then linearized with assumptions that are appropriate for a launch vehicle, so that the resulting equations may be inverted by the flight controller in order to compute the control signals necessary to generate the desired response from the vehicle. Next, the development of the hybrid adaptive launch vehicle ascent flight control architecture is discussed in detail. Alterations of the generic hybrid adaptive control architecture include the incorporation of a command conversion operation which transforms guidance input from quaternion form (as provided by NASA) to the body-fixed angular rate commands needed by the hybrid adaptive flight controller, development of a Newton's method based online parameter update that is modified to include a step size which regulates the rate of change in the parameter estimates, comparison of the modified Newton's method and recursive least squares online parameter update algorithms, modification of the neural network's input structure to accommodate for the nature of the nonlinearities present in a launch vehicle's ascent flight, examination of both tracking error based and modeling error based neural network weight update laws, and integration of feedback filters for the purpose of preventing harmful interaction between the flight control system and flexible structural modes. To validate the hybrid adaptive controller, a high-fidelity Ares I ascent flight simulator and a classical gain-scheduled proportional-integral-derivative (PID) ascent flight controller were obtained from the NASA Marshall Space Flight Center. The classical PID flight controller is used as a benchmark when analyzing the performance of the hybrid adaptive flight controller. Simulations are conducted which model both nominal and off-nominal flight conditions with structural flexibility of the vehicle either enabled or disabled. First, rigid body ascent simulations are performed with the hybrid adaptive controller under nominal flight conditions for the purpose of selecting the update laws which drive the indirect and direct adaptive components. With the neural network disabled, the results revealed that the recursive least squares online parameter update caused high frequency oscillations to appear in the engine gimbal commands. This is highly undesirable for long and slender launch vehicles, such as the Ares I, because such oscillation of the rocket nozzle could excite unstable structural flex modes. In contrast, the modified Newton's method online parameter update produced smooth control signals and was thus selected for use in the hybrid adaptive launch vehicle flight controller. In the simulations where the online parameter identification algorithm was disabled, the tracking error based neural network weight update law forced the network's output to diverge despite repeated reductions of the adaptive learning rate. As a result, the modeling error based neural network weight update law (which generated bounded signals) is utilized by the hybrid adaptive controller in all subsequent simulations. Comparing the PID and hybrid adaptive flight controllers under nominal flight conditions in rigid body ascent simulations showed that their tracking error magnitudes are similar for a period of time during the middle of the ascent phase. Though the PID controller performs better for a short interval around the 20 second mark, the hybrid adaptive controller performs far better from roughly 70 to 120 seconds. Elevating the aerodynamic loads by increasing the force and moment coefficients produced results very similar to the nominal case. However, applying a 5% or 10% thrust reduction to the first stage rocket motor causes the tracking error magnitude observed by the PID controller to be significantly elevated and diverge rapidly as the simulation concludes. In contrast, the hybrid adaptive controller steadily maintains smaller errors (often less than 50% of the corresponding PID value). Under the same sets of flight conditions with flexibility enabled, the results exhibit similar trends with the hybrid adaptive controller performing even better in each case. Again, the reduction of the first stage rocket motor's thrust clearly illustrated the superior robustness of the hybrid adaptive flight controller.

Indirect adaptive output feedback control of a biorobotic AUV using pectoral-like mechanical fins.

PubMed

Naik, Mugdha S; Singh, Sahjendra N; Mittal, Rajat

2009-06-01

This paper treats the question of servoregulation of autonomous underwater vehicles (AUVs) in the yaw plane using pectoral-like mechanical fins. The fins attached to the vehicle have oscillatory swaying and yawing motion. The bias angle of the angular motion of the fin is used for the purpose of control. Of course, the design approach considered here is applicable to AUVs for other choices of oscillation patterns of the fins, which produce periodic forces and moments. It is assumed that the vehicle parameters, hydrodynamic coefficients, as well the fin forces and moments are unknown. For the trajectory control of the yaw angle, a sampled-data indirect adaptive control system using output (yaw angle) feedback is derived. The control system has a modular structure, which includes a parameter identifier and a stabilizer. For the control law derivation, an internal model of the exosignals (reference signal (constant or ramp) and constant disturbance) is included. Unlike the direct adaptive control scheme, the derived control law is applicable to minimum as well as nonminimum phase biorobotic AUVs (BAUVs). This is important, because for most of the fin locations on the vehicle, the model is a nonminimum phase. In the closed-loop system, the yaw angle trajectory tracking error converges to zero and the remaining state variables remain bounded. Simulation results are presented which show that the derived modular control system accomplishes precise set point yaw angle control and turning maneuvers in spite of the uncertainties in the system parameters using only yaw angle feedback.

Adaptive Optimal Control Using Frequency Selective Information of the System Uncertainty With Application to Unmanned Aircraft.

PubMed

Maity, Arnab; Hocht, Leonhard; Heise, Christian; Holzapfel, Florian

2018-01-01

A new efficient adaptive optimal control approach is presented in this paper based on the indirect model reference adaptive control (MRAC) architecture for improvement of adaptation and tracking performance of the uncertain system. The system accounts here for both matched and unmatched unknown uncertainties that can act as plant as well as input effectiveness failures or damages. For adaptation of the unknown parameters of these uncertainties, the frequency selective learning approach is used. Its idea is to compute a filtered expression of the system uncertainty using multiple filters based on online instantaneous information, which is used for augmentation of the update law. It is capable of adjusting a sudden change in system dynamics without depending on high adaptation gains and can satisfy exponential parameter error convergence under certain conditions in the presence of structured matched and unmatched uncertainties as well. Additionally, the controller of the MRAC system is designed using a new optimal control method. This method is a new linear quadratic regulator-based optimal control formulation for both output regulation and command tracking problems. It provides a closed-form control solution. The proposed overall approach is applied in a control of lateral dynamics of an unmanned aircraft problem to show its effectiveness.

REVIEW: Internal models in sensorimotor integration: perspectives from adaptive control theory

NASA Astrophysics Data System (ADS)

Tin, Chung; Poon, Chi-Sang

2005-09-01

Internal models and adaptive controls are empirical and mathematical paradigms that have evolved separately to describe learning control processes in brain systems and engineering systems, respectively. This paper presents a comprehensive appraisal of the correlation between these paradigms with a view to forging a unified theoretical framework that may benefit both disciplines. It is suggested that the classic equilibrium-point theory of impedance control of arm movement is analogous to continuous gain-scheduling or high-gain adaptive control within or across movement trials, respectively, and that the recently proposed inverse internal model is akin to adaptive sliding control originally for robotic manipulator applications. Modular internal models' architecture for multiple motor tasks is a form of multi-model adaptive control. Stochastic methods, such as generalized predictive control, reinforcement learning, Bayesian learning and Hebbian feedback covariance learning, are reviewed and their possible relevance to motor control is discussed. Possible applicability of a Luenberger observer and an extended Kalman filter to state estimation problems—such as sensorimotor prediction or the resolution of vestibular sensory ambiguity—is also discussed. The important role played by vestibular system identification in postural control suggests an indirect adaptive control scheme whereby system states or parameters are explicitly estimated prior to the implementation of control. This interdisciplinary framework should facilitate the experimental elucidation of the mechanisms of internal models in sensorimotor systems and the reverse engineering of such neural mechanisms into novel brain-inspired adaptive control paradigms in future.

Canine and feline fundus photography and videography using a nonpatented 3D printed lens adapter for a smartphone.

PubMed

Espinheira Gomes, Filipe; Ledbetter, Eric

2018-05-11

To describe an indirect funduscopy imaging technique for dogs and cats using low cost and widely available equipment: a smartphone, a three-dimensional (3D) printed indirect lens adapter, and a 40 diopters (D) indirect ophthalmoscopy lens. Fundus videography was performed in dogs and cats using a 40D indirect ophthalmoscopy lens and a smartphone fitted with a 3D printed indirect lens adapter. All animals were pharmacologically dilated with topical tropicamide 1% solution. Eyelid opening and video recording were performed using standard binocular indirect ophthalmoscopy technique. All videos were uploaded to a computer, and still images were selected and acquired for archiving purposes. Fundic images were manipulated to represent the true anatomy of the fundus. It was possible to promptly obtain good quality images from normal and diseased retinas using the nonpatented 3D printed, lens adapter for a smartphone. Fundic imaging using a smartphone can be performed with minimal investment. This simple imaging modality can be used by veterinary ophthalmologists and general practitioners to acquire, archive, and share images of the retina. The quality of images obtained will likely improve with developments in smartphone camera software and hardware. © 2018 American College of Veterinary Ophthalmologists.

Rapid adaptation of invertebrate pests to climatic stress?

PubMed

Hoffmann, Ary A

2017-06-01

There is surprisingly little information on adaptive responses of pests and disease vectors to climatic stresses even though the short generation times and large population sizes associated with pests make rapid adaptation likely. Most evidence of adaptive differentiation has been obtained from geographic comparisons and these can directly or indirectly indicate rates of adaptation where historical data on invasions are available. There is very little information on adaptive shifts in pests detected through molecular comparisons even though the genomes of many pests are now available and can help to identify markers underlying adaptation. While the limited evidence available points to frequent rapid adaptation that can affect pest and disease vector control, constraints to adaptation are also evident and a predictive framework around the likelihood and limits of rapid adaptation is required. Copyright © 2017 Elsevier Inc. All rights reserved.

Climate change and animal health in Africa.

PubMed

Van den Bossche, P; Coetzer, J A W

2008-08-01

Climate change is expected to have direct and indirect impacts on African livestock. Direct impacts include increased ambient temperature, floods and droughts. Indirect impacts are the result of reduced availability of water and forage and changes in the environment that promote the spread of contagious diseases through increased contact between animals, or increased survival or availability of the agent or its intermediate host. The distribution and prevalence of vector-borne diseases may be the most significant effect of climate change. The potential vulnerability of the livestock industry will depend on its ability to adapt to such changes. Enhancing this adaptive capacity presents a practical way of coping with climate change. Adaptive capacity could be increased by enabling the African livestock owner to cope better with animal health problems through appropriate policy measures and institutional support. Developing an effective and sustainable animal health service, associated surveillance and emergency preparedness systems and sustainable disease control and prevention programmes is perhaps the most important strategy for dealing with climate change in many African countries.

Slip control design of electric vehicle using indirect Dahlin Adaptive Pid

NASA Astrophysics Data System (ADS)

Fauzi, I. R.; Koko, F.; Kirom, M. R.

2016-11-01

In this paper the problem to be solved is to build a slip control on a wheel that may occur in an electric car wheel. Slip is the difference in vehicle velocity and wheel tangential velocity and to be enlarged when the torque given growing. Slip can be reduced by controlling the torque of the wheel so that the wheel tangential speed does not exceed the vehicle speed. The experiment in this paper is a simulation using MATLAB Simulink and using Adaptive control. The response adaptive PID control more quickly 1.5 s than PID control and can controlled wheel tangential speed close to the vehicle velocity on a dry asphalt, wet asphalt, snow and ice surface sequent at time 2s, 4s, 10s, and 50s. The maximum acceleration of the vehicle (V) on the surface of the dry asphalt, wet asphalt, snow, and ice surface sequent at 8.9 m/s2, 6.2 m/s2, 2.75 m/s2, and 0.34 m/s2.

Design and implementation of adaptive PI control schemes for web tension control in roll-to-roll (R2R) manufacturing.

PubMed

Raul, Pramod R; Pagilla, Prabhakar R

2015-05-01

In this paper, two adaptive Proportional-Integral (PI) control schemes are designed and discussed for control of web tension in Roll-to-Roll (R2R) manufacturing systems. R2R systems are used to transport continuous materials (called webs) on rollers from the unwind roll to the rewind roll. Maintaining web tension at the desired value is critical to many R2R processes such as printing, coating, lamination, etc. Existing fixed gain PI tension control schemes currently used in industrial practice require extensive tuning and do not provide the desired performance for changing operating conditions and material properties. The first adaptive PI scheme utilizes the model reference approach where the controller gains are estimated based on matching of the actual closed-loop tension control systems with an appropriately chosen reference model. The second adaptive PI scheme utilizes the indirect adaptive control approach together with relay feedback technique to automatically initialize the adaptive PI gains. These adaptive tension control schemes can be implemented on any R2R manufacturing system. The key features of the two adaptive schemes is that their designs are simple for practicing engineers, easy to implement in real-time, and automate the tuning process. Extensive experiments are conducted on a large experimental R2R machine which mimics many features of an industrial R2R machine. These experiments include trials with two different polymer webs and a variety of operating conditions. Implementation guidelines are provided for both adaptive schemes. Experimental results comparing the two adaptive schemes and a fixed gain PI tension control scheme used in industrial practice are provided and discussed. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

A Review of Control Strategy of the Large-scale of Electric Vehicles Charging and Discharging Behavior

NASA Astrophysics Data System (ADS)

Kong, Lingyu; Han, Jiming; Xiong, Wenting; Wang, Hao; Shen, Yaqi; Li, Ying

2017-05-01

Large scale access of electric vehicles will bring huge challenges to the safe operation of the power grid, and it’s important to control the charging and discharging of the electric vehicle. First of all, from the electric quality and network loss, this paper points out the influence on the grid caused by electric vehicle charging behaviour. Besides, control strategy of electric vehicle charging and discharging has carried on the induction and the summary from the direct and indirect control. Direct control strategy means control the electric charging behaviour by controlling its electric vehicle charging and discharging power while the indirect control strategy by means of controlling the price of charging and discharging. Finally, for the convenience of the reader, this paper also proposed a complete idea of the research methods about how to study the control strategy, taking the adaptability and possibility of failure of electric vehicle control strategy into consideration. Finally, suggestions on the key areas for future research are put up.

Perceived Control is a Transdiagnostic Predictor of Cognitive-Behavior Therapy Outcome for Anxiety Disorders

PubMed Central

Gallagher, Matthew W.; Naragon-Gainey, Kristin; Brown, Timothy A.

2013-01-01

Perceived control has been proposed to be a general psychological vulnerability factor that confers an elevated risk for developing anxiety disorders, but there is limited research examining perceived control during cognitive-behavioral therapies (CBT). The present study examined whether treatment resulted in improvements in perceived control, and the indirect effects of CBT on changes in symptoms of obsessive-compulsive disorder, social phobia, generalized anxiety disorder, and panic disorder via changes in perceived control. Participants (n = 606) were a large clinical sample presenting for treatment at an outpatient anxiety disorders clinic. Participants completed a series of self-report questionnaires and a structured clinical interview at an intake evaluation and at two follow-up assessments 12 and 24 months later, with the majority of participants initiating CBT between the first two assessments. Results of latent growth curve models indicated that individuals initiating CBT subsequently reported large increases in perceived control and significant indirect effects of treatment on intraindividual changes in each of the four anxiety disorders examined via intraindividual changes in perceived control. These results suggest that the promotion of more adaptive perceptions of control is associated with recovery from anxiety disorders. Furthermore, the consistent finding of indirect effects across the four anxiety disorders examined underscores the transdiagnostic importance of perceived control in predicting CBT outcomes. PMID:24563563

Comparison of the marginal adaptation of direct and indirect composite inlay restorations with optical coherence tomography.

PubMed

Türk, Ayşe Gözde; Sabuncu, Metin; Ünal, Sena; Önal, Banu; Ulusoy, Mübin

2016-01-01

The purpose of the study was to use the photonic imaging modality of optical coherence tomography (OCT) to compare the marginal adaptation of composite inlays fabricated by direct and indirect techniques. Class II cavities were prepared on 34 extracted human molar teeth. The cavities were randomly divided into two groups according to the inlay fabrication technique. The first group was directly restored on cavities with a composite (Esthet X HD, Dentsply, Germany) after isolating. The second group was indirectly restored with the same composite material. Marginal adaptations were scanned before cementation with an invisible infrared light beam of OCT (Thorlabs), allowing measurement in 200 µm intervals. Restorations were cemented with a self-adhesive cement resin (SmartCem2, Dentsply), and then marginal adaptations were again measured with OCT. Mean values were statistically compared by using independent-samples t-test and paired samples t-test (p<0.05), before and after cementation. Direct inlays presented statistically smaller marginal discrepancy values than indirect inlays, before (p=0.00001442) and after (p=0.00001466) cementation. Marginal discrepancy values were increased for all restorations after cementation (p=0.00008839, p=0.000000952 for direct and indirect inlays, respectively). The mean marginal discrepancy value of the direct group increased from 56.88±20.04 µm to 91.88±31.7 µm, whereas the indirect group increased from 107.54±35.63 µm to 170.29±54.83 µm. Different techniques are available to detect marginal adaptation of restorations, but the OCT system can give quantitative information about resin cement thickness and its interaction between tooth and restoration in a nondestructive manner. Direct inlays presented smaller marginal discrepancy than indirect inlays. The marginal discrepancy values were increased for all restorations that refer to cement thickness after cementation.

The Role of Perceived Parental Autonomy Support in Academic Achievement of Asian and Latino American Adolescents

ERIC Educational Resources Information Center

Jiang, Ying Hong; Yau, Jenny; Bonner, Patricia; Chiang, Linda

2011-01-01

Introduction: Driven by an overarching conceptual framework adapted from Self-Determination Theory, this study tested the direct and indirect effects of perceived parental academia autonomy support vs. academic planning control on the interrelated variables of adolescents' self-esteem, academic motivation, and academic achievement, using…

Unhealthy weight control behaviours in adolescent girls: a process model based on self-determination theory.

PubMed

Thøgersen-Ntoumani, Cecilie; Ntoumanis, Nikos; Nikitaras, Nikitas

2010-06-01

This study used self-determination theory (Deci, E.L., & Ryan, R.M. (2000). The 'what' and 'why' of goal pursuits: Human needs and the self-determination of behavior. Psychological Inquiry, 11, 227-268.) to examine predictors of body image concerns and unhealthy weight control behaviours in a sample of 350 Greek adolescent girls. A process model was tested which proposed that perceptions of parental autonomy support and two life goals (health and image) would predict adolescents' degree of satisfaction of their basic psychological needs. In turn, psychological need satisfaction was hypothesised to negatively predict body image concerns (i.e. drive for thinness and body dissatisfaction) and, indirectly, unhealthy weight control behaviours. The predictions of the model were largely supported indicating that parental autonomy support and adaptive life goals can indirectly impact upon the extent to which female adolescents engage in unhealthy weight control behaviours via facilitating the latter's psychological need satisfaction.

Integration of Online Parameter Identification and Neural Network for In-Flight Adaptive Control

NASA Technical Reports Server (NTRS)

Hageman, Jacob J.; Smith, Mark S.; Stachowiak, Susan

2003-01-01

An indirect adaptive system has been constructed for robust control of an aircraft with uncertain aerodynamic characteristics. This system consists of a multilayer perceptron pre-trained neural network, online stability and control derivative identification, a dynamic cell structure online learning neural network, and a model following control system based on the stochastic optimal feedforward and feedback technique. The pre-trained neural network and model following control system have been flight-tested, but the online parameter identification and online learning neural network are new additions used for in-flight adaptation of the control system model. A description of the modification and integration of these two stand-alone software packages into the complete system in preparation for initial flight tests is presented. Open-loop results using both simulation and flight data, as well as closed-loop performance of the complete system in a nonlinear, six-degree-of-freedom, flight validated simulation, are analyzed. Results show that this online learning system, in contrast to the nonlearning system, has the ability to adapt to changes in aerodynamic characteristics in a real-time, closed-loop, piloted simulation, resulting in improved flying qualities.

Comparative evaluation of effects of bleaching on color stability and marginal adaptation of discolored direct and indirect composite laminate veneers under in vivo conditions.

PubMed

Jain, Veena; Das, Taposh K; Pruthi, Gunjan; Shah, Naseem; Rajendiran, Suresh

2015-01-01

Change in color and loss of marginal adaptation of tooth colored restorative materials is not acceptable. Bleaching is commonly used for treating discolored teeth. However, the literature is scanty regarding its effect on color and marginal adaptation of direct and indirect composite laminate veneers (CLVs) under in vivo conditions. Purpose of the study was to determine the effect of bleaching on color change and marginal adaptation of direct and indirect CLVs over a period of time when exposed to the oral environment. For this purpose, a total of 14 subjects irrespective of age and sex indicated for CLV restorations on maxillary anterior teeth were selected following the inclusion and exclusion criteria. For each subject, indirect CLVs were fabricated and looted in the first quadrant (Group 1) and direct CLV's (Group 2), were given in the second quadrant. Color change was assessed clinically using intra-oral digital spectrophotometer and marginal adaptation was assessed on epoxy resin replica of the tooth-restoration interface under scanning electron microscope. After 6 months, the subjects underwent a home bleaching regimen for 14 days using 10% carbamide peroxide. The assessment of color change and marginal adaptation was done at 6 months after veneering (0-180 days), immediately after the bleaching regimen (0-194 days) and 3 months after the bleaching regimen (0-284 days). The difference in median color change (ΔE) between the groups was tested using Wilcoxon rank sum test while the median color change with time within the groups was tested using Wilcoxon signed rank test. The difference in the rates of marginal adaptation was tested between the groups using Chi-square/Fisher's exact test. Bleaching led to statistically significant color change at cervical (CE), middle and incisal (IE) regions when direct and indirect composites were compared (P < 0.05). During intra-group comparison, direct CLV's showed significant color change at CE and IE regions when ΔE was compared at 180 days and 284 days (CE 10 vs. CE 30, P = 0.008, IE 10 vs. IE 30, P = 0.003). No significant differences were found when within group comparison was made for indirect laminates. Intergroup comparison between the groups showed significant difference in marginal adaptation at CE margin at all.time points (at baseline, P = 0.005; at 180 days, P = 0.007; 194 days, P = 0.025; at 284 days, P = 0.067). After bleaching, indirect CLVs performed better in terms of color stability whereas direct CLVs performed better in terms of marginal adaptation. Indirect composites should be preferred to direct composites as veneering materials as they have better color stability. Special attention should be given to their marginal adaptation especially in the CE region. Bleaching should be avoided in patients with composite restorations in the mouth.

A temperature control design for a tapered element oscillating microbalance sensing surface

NASA Technical Reports Server (NTRS)

1982-01-01

A design study is presented which shows that a tapered element oscillating microbalance can be adapted for temperature control under space application by mating with multistage thermoelectric coolers in such a way that an integral structure evolves. The control of the temperature of the sensing surface can be achieved in a number of ways. An indirect method which uses a measurement of the absorbed power is recommended. The design goals can be met if a relaxation of the power requirement can be considered.

Comparison of the marginal adaptation of direct and indirect composite inlay restorations with optical coherence tomography

PubMed Central

TÜRK, Ayşe Gözde; SABUNCU, Metin; ÜNAL, Sena; ÖNAL, Banu; ULUSOY, Mübin

2016-01-01

ABSTRACT Objective The purpose of the study was to use the photonic imaging modality of optical coherence tomography (OCT) to compare the marginal adaptation of composite inlays fabricated by direct and indirect techniques. Material and Methods Class II cavities were prepared on 34 extracted human molar teeth. The cavities were randomly divided into two groups according to the inlay fabrication technique. The first group was directly restored on cavities with a composite (Esthet X HD, Dentsply, Germany) after isolating. The second group was indirectly restored with the same composite material. Marginal adaptations were scanned before cementation with an invisible infrared light beam of OCT (Thorlabs), allowing measurement in 200 µm intervals. Restorations were cemented with a self-adhesive cement resin (SmartCem2, Dentsply), and then marginal adaptations were again measured with OCT. Mean values were statistically compared by using independent-samples t-test and paired samples t-test (p<0.05), before and after cementation. Results Direct inlays presented statistically smaller marginal discrepancy values than indirect inlays, before (p=0.00001442) and after (p=0.00001466) cementation. Marginal discrepancy values were increased for all restorations after cementation (p=0.00008839, p=0.000000952 for direct and indirect inlays, respectively). The mean marginal discrepancy value of the direct group increased from 56.88±20.04 µm to 91.88±31.7 µm, whereas the indirect group increased from 107.54±35.63 µm to 170.29±54.83 µm. Different techniques are available to detect marginal adaptation of restorations, but the OCT system can give quantitative information about resin cement thickness and its interaction between tooth and restoration in a nondestructive manner. Conclusions Direct inlays presented smaller marginal discrepancy than indirect inlays. The marginal discrepancy values were increased for all restorations that refer to cement thickness after cementation. PMID:27556210

Recent developments in learning control and system identification for robots and structures

NASA Technical Reports Server (NTRS)

Phan, M.; Juang, J.-N.; Longman, R. W.

1990-01-01

This paper reviews recent results in learning control and learning system identification, with particular emphasis on discrete-time formulation, and their relation to adaptive theory. Related continuous-time results are also discussed. Among the topics presented are proportional, derivative, and integral learning controllers, time-domain formulation of discrete learning algorithms. Newly developed techniques are described including the concept of the repetition domain, and the repetition domain formulation of learning control by linear feedback, model reference learning control, indirect learning control with parameter estimation, as well as related basic concepts, recursive and non-recursive methods for learning identification.

Avuncular tendencies and the evolution of male androphilia in Samoan fa'afafine.

PubMed

Vasey, Paul L; VanderLaan, Doug P

2010-08-01

The kin selection hypothesis for male androphilia holds that genes for male androphilia can be maintained in a population if the fitness costs of not reproducing directly are offset by enhancing indirect fitness. Kin share some proportion of genes identical by virtue of descent. Theoretically speaking, androphilic males can increase their fitness indirectly by allocating altruistic behavior toward kin, which, in turn, allows kin to increase their reproductive success. Research conducted in Independent Samoa has shown that androphilic males (known locally as fa'afafine) report significantly higher avuncular tendencies relative to gynephilic men. Here, we replicate this sexual orientation difference, using a larger, independent sample, suggesting that the documented sexual orientation difference in avuncular tendencies in Independent Samoa is genuine. We also extend previous research by showing that fa'afafine exhibit significantly higher avuncular tendencies even when compared to a more closely matched control group that also lacks direct parental care responsibilities (i.e., gynephilic men with no children). Although the greater avuncular tendencies of fa'afafine relative to gynephilic men are consistent with the predictions of the kin selection hypothesis for male androphilia, further research is needed before deeming male androphilia an adaptation for promoting elevated avuncularity. Likewise, more research is needed before deeming elevated avuncularity in fa'afafine an evolved adaptation for promoting indirect fitness. We discuss these findings in the context of alternative evolutionary explanations for male androphilia (i.e., an evolved by-product of an adaptation).

Indirect adaptive fuzzy fault-tolerant tracking control for MIMO nonlinear systems with actuator and sensor failures.

PubMed

Bounemeur, Abdelhamid; Chemachema, Mohamed; Essounbouli, Najib

2018-05-10

In this paper, an active fuzzy fault tolerant tracking control (AFFTTC) scheme is developed for a class of multi-input multi-output (MIMO) unknown nonlinear systems in the presence of unknown actuator faults, sensor failures and external disturbance. The developed control scheme deals with four kinds of faults for both sensors and actuators. The bias, drift, and loss of accuracy additive faults are considered along with the loss of effectiveness multiplicative fault. A fuzzy adaptive controller based on back-stepping design is developed to deal with actuator failures and unknown system dynamics. However, an additional robust control term is added to deal with sensor faults, approximation errors, and external disturbances. Lyapunov theory is used to prove the stability of the closed loop system. Numerical simulations on a quadrotor are presented to show the effectiveness of the proposed approach. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Performance recovery of a class of uncertain non-affine systems with unmodelled dynamics: an indirect dynamic inversion method

NASA Astrophysics Data System (ADS)

Yi, Bowen; Lin, Shuyi; Yang, Bo; Zhang, Weidong

2018-02-01

This paper presents an output feedback indirect dynamic inversion (IDI) approach for a class of uncertain nonaffine systems with input unmodelled dynamics. Compared with previous approaches to achieve performance recovery, the proposed method aims at dealing with a broader class of nonaffine-in-control systems with triangular structure. An IDI state feedback law is designed first, in which less knowledge of the model plant is needed compared to earlier approximate dynamic inversion methods, thus yielding more robust performance. After that, an extended high-gain observer is designed to accomplish the task with output feedback. Finally, we prove that the designed IDI controller is equivalent to an adaptive proportional-integral (PI) controller, with respect to both time response equivalence and robustness equivalence. The conclusion implies that for the studied strict-feedback non-affine systems with unmodelled dynamics, there always exits a PI controller to stabilise the systems. The effectiveness and benefits of the designed approach are verified by three examples.

Analysis of convergence of an evolutionary algorithm with self-adaptation using a stochastic Lyapunov function.

PubMed

Semenov, Mikhail A; Terkel, Dmitri A

2003-01-01

This paper analyses the convergence of evolutionary algorithms using a technique which is based on a stochastic Lyapunov function and developed within the martingale theory. This technique is used to investigate the convergence of a simple evolutionary algorithm with self-adaptation, which contains two types of parameters: fitness parameters, belonging to the domain of the objective function; and control parameters, responsible for the variation of fitness parameters. Although both parameters mutate randomly and independently, they converge to the "optimum" due to the direct (for fitness parameters) and indirect (for control parameters) selection. We show that the convergence velocity of the evolutionary algorithm with self-adaptation is asymptotically exponential, similar to the velocity of the optimal deterministic algorithm on the class of unimodal functions. Although some martingale inequalities have not be proved analytically, they have been numerically validated with 0.999 confidence using Monte-Carlo simulations.

[What factors of prosocial behavior evoke recipients’ gratitude and indebtedness? An experimental examination].

PubMed

Shiraki, Yuma; Igarashi, Tasuku

2016-12-01

We examined two psychological processes of prosocial behavior: feeling gratitude and indebtedness. First, we asked if the value of the behavior for the receiver promotes gratitude; and second if the cost of the behavior for the giver promotes indebtedness. Gratitude and indebtedness were measured as behavioral indices of a quid pro quo (indirect reciprocity and direct reciprocity) to avoid social desirability effects in self-report measures. In Study 1, 119 undergraduates recalled a past experience in which they had been the recipients of prosocial behavior while emphasizing the value, cost, or situation (control) of the event. The level of gratitude was higher, and indirect reciprocity was observed more frequently, in the value condition than in the cost and control conditions. Indebtedness, however, did not differ across the conditions. In Study 2, 59 participants received a gift (the value and cost of which were manipulated) from an imaginary confederate. The value manipulation promoted indirect reciprocity, and both value and cost manipulations encouraged direct reciprocity. Implications for adaptive functions of gratitude in social selection processes are discussed.

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.

Certainty Equivalence M-MRAC for Systems with Unmatched Uncertainties

NASA Technical Reports Server (NTRS)

Stepanyan, Vahram; Krishnakumar, Kalmanje

2012-01-01

The paper presents a certainty equivalence state feedback indirect adaptive control design method for the systems of any relative degree with unmatched uncertainties. The approach is based on the parameter identification (estimation) model, which is completely separated from the control design and is capable of producing parameter estimates as fast as the computing power allows without generating high frequency oscillations. It is shown that the system's input and output tracking errors can be systematically decreased by the proper choice of the design parameters.

An automated approach to the segmentation of HEp-2 cells for the indirect immunofluorescence ANA test.

PubMed

Tonti, Simone; Di Cataldo, Santa; Bottino, Andrea; Ficarra, Elisa

2015-03-01

The automatization of the analysis of Indirect Immunofluorescence (IIF) images is of paramount importance for the diagnosis of autoimmune diseases. This paper proposes a solution to one of the most challenging steps of this process, the segmentation of HEp-2 cells, through an adaptive marker-controlled watershed approach. Our algorithm automatically conforms the marker selection pipeline to the peculiar characteristics of the input image, hence it is able to cope with different fluorescent intensities and staining patterns without any a priori knowledge. Furthermore, it shows a reduced sensitivity to over-segmentation errors and uneven illumination, that are typical issues of IIF imaging. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Peculiarities of the psychological status of first-year students in terms of university education].

PubMed

Buduk-ool, L K; Khovalyg, A M

2016-01-01

Peculiarities There was performed the study of the mental status of first-year students enrolled in the Tuvan state University. There were detected levels of reactive and personal anxiety, adaptive capacity, the level of social and psychological adaptation and aggression. Adaptation potential in students is within limits of the satisfactory one, there was no detected person with poor adaptive capacity and failure of adaptation, that indicates to the genetically fixed ability of the students’ body to adapt to living conditions. In a state of psychological adjustment there was revealed the more higher level of anxiety in Tuvan students, which is caused by the poor living conditions. More satisfactory condition is typical for the social and psychological adaptation, since in all students values of test scales are within normal limits.There were shown gender differences in adaptation and psychological status of students. Boys have more lower indices of indirect and verbal aggression, anger, resentment, suspicion, guilt. Girls are characterized by higher hostility, at that it even exceeds standard values. In the group of students with a high personal anxiety no differences in adaptive capacities were found, and in students with moderate personal anxiety there were significantly more boys with stress adaptation than girls. Analysis of the socio-psychological adaptation of first-year students shows that in all students values of the test scales are normal, but in young men, indices are higher that indicates to a more successful socialization in the environment of the university. Correlation analysis of indices of aggressiveness and socio-psychological adaptation revealed weak negative relationships between index of aggressiveness with maladaptiveness, non-acceptance of others, emotional comfort in boys. In girls “aggressiveness” positively correlates with the such indices as acceptance of others and adaptation. Factor analysis in young men revealed the first factor, labeled as maladjustment because it included indirect aggression, maladaptiveness, self-rejection, emotional discomfort and external control. In girls first factor combines indices: adaptability, self-acceptance, adaptation (integral), self-acceptance, emotional comfort, the desire to dominate and this factor was labeled as adaptation.

Adaptation in protein fitness landscapes is facilitated by indirect paths

PubMed Central

Wu, Nicholas C; Dai, Lei; Olson, C Anders; Lloyd-Smith, James O; Sun, Ren

2016-01-01

The structure of fitness landscapes is critical for understanding adaptive protein evolution. Previous empirical studies on fitness landscapes were confined to either the neighborhood around the wild type sequence, involving mostly single and double mutants, or a combinatorially complete subgraph involving only two amino acids at each site. In reality, the dimensionality of protein sequence space is higher (20L) and there may be higher-order interactions among more than two sites. Here we experimentally characterized the fitness landscape of four sites in protein GB1, containing 204 = 160,000 variants. We found that while reciprocal sign epistasis blocked many direct paths of adaptation, such evolutionary traps could be circumvented by indirect paths through genotype space involving gain and subsequent loss of mutations. These indirect paths alleviate the constraint on adaptive protein evolution, suggesting that the heretofore neglected dimensions of sequence space may change our views on how proteins evolve. DOI: http://dx.doi.org/10.7554/eLife.16965.001 PMID:27391790

The Direct-Indirect Technique for Composite Restorations Revisited.

PubMed

Ritter, André V; Fahl, Newton; Vargas, Marcos; Maia, Rodrigo R

2017-06-01

In the direct-indirect composite technique, composite is applied to a nonretentive tooth preparation (eg, a noncarious cervical lesion or a veneer/inlay/onlay preparation) without any bonding agent, sculpted to a primary anatomic form, and light-cured. The partially polymerized restoration is then removed from the preparation and finished and tempered extraorally chairside. The finished inlay is bonded to the preparation using a resin-based luting agent. Advantages of this technique include enhanced physical and mechanical properties afforded by the extraoral chairside tempering process because of increased monomer conversion, and greater operator control over the final marginal adaptation, surface finishing and polishing, and anatomy of the restoration, given that these elements are defined outside of the patient's mouth. The direct-indirect approach also affords enhanced gingival health and patient comfort. This article presents a clinical case in which the direct-indirect composite technique was used to restore three noncarious cervical lesions on the same quadrant on an adult patient. Clinical steps and tips for success are offered. The authors also present scanning electron microscope and atomic force microscope images showing the excellent marginal fit obtained with the direct-indirect composite technique.

Influence of polyurethane resin dies on the fit and adaptation of full veneer crowns.

PubMed

Lillywhite, Graeme R R; Vohra, Fahim

2015-01-01

Polyurethane resin is a possible alternative to type IV dental stone for fabrication of indirect restorations however its dimensional accuracy is questionable. The aim was to investigate the dimensional accuracy of silica filled polyurethane resin die material by evaluating the marginal fit and adaptation of indirect gold castings. Experimental, in vitro study. Totally 40 copper plated replicas of a nickel chrome master die analogous to a veneer gold crown preparation were made and impressions recorded using polyvinylsiloxane material. Twenty impressions were poured in type IV dental stone (control group (Vel-mix, Kerr, UK) and the remaining (n = 20) in silica filled polyurethane die material (test group) (Alpha Die MF, CA, USA). Gold castings were fabricated for each die using standardized techniques. The castings were seated on their respective copper plated dies, embedded in resin and sectioned. The specimens were analyzed by measuring marginal opening and the area beneath the casting at a ×63 magnification and using image analysis software. Data were analyzed using a Student's t-test. No significant difference was observed between the experimental groups (P > 0.05). The mean marginal opening for type IV, dental stone and polyurethane resin, was 57 ± 22.6 μm and 63.47 ± 27.1 μm, respectively. Stone displayed a smaller area beneath the casting (31581 ± 16297 μm 2 ) as compared to polyurethane resin (35003 ± 23039 μm 2 ). The fit and adaptation of indirect gold castings made on polyurethane and type IV dental stone dies were comparable.

Genic Variability and Strategies of Adaptation in Animals

PubMed Central

Selander, Robert K.; Kaufman, Donald W.

1973-01-01

Levels of genic heterozygosity, as measured by surveys of allozymic variation, are much lower in populations of large, mobile animals (most vertebrates) than in those of small, relatively immobile animals (most invertebrates). This difference is not consistent with theories relating variability to population size (species number) or dispersal ability (gene flow), but it is predicted by Levins' theory of adaptive strategies in relation to environmental uncertainty (“grain”). Mobility and degree of homeostatic control apparently are important factors influencing levels of genic heterozygosity in natural populations. The results argue indirectly that at least a major proportion of allozymic variation is maintained by natural selection. PMID:4515944

Effects of cumulative stress and impulsivity on smoking status.

PubMed

Ansell, Emily B; Gu, Peihua; Tuit, Keri; Sinha, Rajita

2012-03-01

The stress-vulnerability model of addiction predicts that environmental factors, such as cumulative stress, will result in individual adaptations that decrease self-control, increase impulsivity, and increase risk for addiction. Impulsivity and cumulative stress are risk factors for tobacco smoking that are rarely examined simultaneously in research. We examined the indirect and direct effects of cumulative adversity in a community sample consisting of 291 men and women who participated in an assessment of cumulative stress, self-reported impulsivity, and smoking history. Data were analyzed using bootstrapping techniques to estimate indirect effects of stress on smoking via impulsivity. Cumulative adversity is associated with smoking status via direct effects and indirect effects through impulsivity scores. Additional models examining specific types of stress indicate contributions of traumatic stress and recent life events as well as chronic relationship stressors. Overall, cumulative stress is associated with increased risk of smoking via increased impulsivity and via pathways independent of impulsivity. These findings support the stress-vulnerability model and highlight the utility of mediation models in assessing how, and for whom, cumulative stress increases risk of current cigarette smoking. Increasing self-control is a target for interventions with individuals who have experienced cumulative adversity. Copyright © 2012 John Wiley & Sons, Ltd.

Effects of cumulative stress and impulsivity on smoking status

PubMed Central

Ansell, Emily B.; Gu, Peihua; Tuit, Keri; Sinha, Rajita

2013-01-01

Objective The stress-vulnerability model of addiction predicts that environmental factors, such as cumulative stress, will result in individual adaptations that decrease self-control, increase impulsivity, and increase risk for addiction. Impulsivity and cumulative stress are risk factors for tobacco smoking that are rarely examined simultaneously in research. Methods We examined the indirect and direct effects of cumulative adversity in a community sample consisting of 291 men and women who participated in an assessment of cumulative stress, self-reported impulsivity, and smoking history. Data were analyzed using bootstrapping techniques to estimate indirect effects of stress on smoking via impulsivity. Results Cumulative adversity is associated with smoking status via direct effects and indirect effects through impulsivity scores. Additional models examining specific types of stress indicate contributions of traumatic stress and recent life events as well as chronic relationship stressors. Conclusions Overall, cumulative stress is associated with increased risk of smoking via increased impulsivity and via pathways independent of impulsivity. These findings support the stress-vulnerability model and highlight the utility of mediation models in assessing how, and for whom, cumulative stress increases risk of current cigarette smoking. Increasing self-control is a target for interventions with individuals who have experienced cumulative adversity. PMID:22389084

Parametric recursive system identification and self-adaptive modeling of the human energy metabolism for adaptive control of fat weight.

PubMed

Őri, Zsolt P

2017-05-01

A mathematical model has been developed to facilitate indirect measurements of difficult to measure variables of the human energy metabolism on a daily basis. The model performs recursive system identification of the parameters of the metabolic model of the human energy metabolism using the law of conservation of energy and principle of indirect calorimetry. Self-adaptive models of the utilized energy intake prediction, macronutrient oxidation rates, and daily body composition changes were created utilizing Kalman filter and the nominal trajectory methods. The accuracy of the models was tested in a simulation study utilizing data from the Minnesota starvation and overfeeding study. With biweekly macronutrient intake measurements, the average prediction error of the utilized carbohydrate intake was -23.2 ± 53.8 kcal/day, fat intake was 11.0 ± 72.3 kcal/day, and protein was 3.7 ± 16.3 kcal/day. The fat and fat-free mass changes were estimated with an error of 0.44 ± 1.16 g/day for fat and -2.6 ± 64.98 g/day for fat-free mass. The daily metabolized macronutrient energy intake and/or daily macronutrient oxidation rate and the daily body composition change from directly measured serial data are optimally predicted with a self-adaptive model with Kalman filter that uses recursive system identification.

Pupil diameter tracks changes in control state predicted by the adaptive gain theory of locus coeruleus function

PubMed Central

Gilzenrat, Mark S.; Nieuwenhuis, Sander; Jepma, Marieke; Cohen, Jonathan D.

2010-01-01

An important dimension of cognitive control is the adaptive regulation of the balance between exploitation (pursuing known sources of reward) and exploration (seeking new ones) in response to changes in task utility. Recent studies have suggested that the locus coeruleus–norepinephrine system may play an important role in this function and that pupil diameter can be used to index locus coeruleus activity. On the basis of this, we reasoned that pupil diameter may correlate closely with control state and associated changes in behavior. Specifically, we predicted that increases in baseline pupil diameter would be associated with decreases in task utility and disengagement from the task (exploration), whereas reduced baseline diameter (but increases in task-evoked dilations) would be associated with task engagement (exploitation). Findings in three experiments were consistent with these predictions, suggesting that pupillometry may be useful as an index of both control state and, indirectly, locus coeruleus function. PMID:20498349

Real-Time Stability and Control Derivative Extraction From F-15 Flight Data

NASA Technical Reports Server (NTRS)

Smith, Mark S.; Moes, Timothy R.; Morelli, Eugene A.

2003-01-01

A real-time, frequency-domain, equation-error parameter identification (PID) technique was used to estimate stability and control derivatives from flight data. This technique is being studied to support adaptive control system concepts currently being developed by NASA (National Aeronautics and Space Administration), academia, and industry. This report describes the basic real-time algorithm used for this study and implementation issues for onboard usage as part of an indirect-adaptive control system. A confidence measures system for automated evaluation of PID results is discussed. Results calculated using flight data from a modified F-15 aircraft are presented. Test maneuvers included pilot input doublets and automated inputs at several flight conditions. Estimated derivatives are compared to aerodynamic model predictions. Data indicate that the real-time PID used for this study performs well enough to be used for onboard parameter estimation. For suitable test inputs, the parameter estimates converged rapidly to sufficient levels of accuracy. The devised confidence measures used were moderately successful.

An Indirect Adaptive Control Scheme in the Presence of Actuator and Sensor Failures

NASA Technical Reports Server (NTRS)

Sun, Joy Z.; Josh, Suresh M.

2009-01-01

The problem of controlling a system in the presence of unknown actuator and sensor faults is addressed. The system is assumed to have groups of actuators, and groups of sensors, with each group consisting of multiple redundant similar actuators or sensors. The types of actuator faults considered consist of unknown actuators stuck in unknown positions, as well as reduced actuator effectiveness. The sensor faults considered include unknown biases and outages. The approach employed for fault detection and estimation consists of a bank of Kalman filters based on multiple models, and subsequent control reconfiguration to mitigate the effect of biases caused by failed components as well as to obtain stability and satisfactory performance using the remaining actuators and sensors. Conditions for fault identifiability are presented, and the adaptive scheme is applied to an aircraft flight control example in the presence of actuator failures. Simulation results demonstrate that the method can rapidly and accurately detect faults and estimate the fault values, thus enabling safe operation and acceptable performance in spite of failures.

Full-order Luenberger observer based on fuzzy-logic control for sensorless field-oriented control of a single-sided linear induction motor.

PubMed

Holakooie, Mohammad Hosein; Ojaghi, Mansour; Taheri, Asghar

2016-01-01

This paper investigates sensorless indirect field oriented control (IFOC) of SLIM with full-order Luenberger observer. The dynamic equations of SLIM are first elaborated to draw full-order Luenberger observer with some simplifying assumption. The observer gain matrix is derived from conventional procedure so that observer poles are proportional to SLIM poles to ensure the stability of system for wide range of linear speed. The operation of observer is significantly impressed by adaptive scheme. A fuzzy logic control (FLC) is proposed as adaptive scheme to estimate linear speed using speed tuning signal. The parameters of FLC are tuned using an off-line method through chaotic optimization algorithm (COA). The performance of the proposed observer is verified by both numerical simulation and real-time hardware-in-the-loop (HIL) implementation. Moreover, a detailed comparative study among proposed and other speed observers is obtained under different operation conditions. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Adaptive evolution of body size subject to indirect effect in trophic cascade system.

PubMed

Wang, Xin; Fan, Meng; Hao, Lina

2017-09-01

Trophic cascades represent a classic example of indirect effect and are wide-spread in nature. Their ecological impact are well established, but the evolutionary consequences have received even less theoretical attention. We theoretically and numerically investigate the trait (i.e., body size of consumer) evolution in response to indirect effect in a trophic cascade system. By applying the quantitative trait evolutionary theory and the adaptive dynamic theory, we formulate and explore two different types of eco-evolutionary resource-consumer-predator trophic cascade model. First, an eco-evolutionary model incorporating the rapid evolution is formulated to investigate the effect of rapid evolution of the consumer's body size, and to explore the impact of density-mediate indirect effect on the population dynamics and trait dynamics. Next, by employing the adaptive dynamic theory, a long-term evolutionary model of consumer body size is formulated to evaluate the effect of long-term evolution on the population dynamics and the effect of trait-mediate indirect effect. Those models admit rich dynamics that has not been observed yet in empirical studies. It is found that, both in the trait-mediated and density-mediated system, the body size of consumer in predator-consumer-resource interaction (indirect effect) evolves smaller than that in consumer-resource and predator-consumer interaction (direct effect). Moreover, in the density-mediated system, we found that the evolution of consumer body size contributes to avoiding consumer extinction (i.e., evolutionary rescue). The trait-mediate and density-mediate effects may produce opposite evolutionary response. This study suggests that the trophic cascade indirect effect affects consumer evolution, highlights a more comprehensive mechanistic understanding of the intricate interplay between ecological and evolutionary force. The modeling approaches provide avenue for study on indirect effects from an evolutionary perspective. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of somatostatin on the growth hormone-insulin-like growth factor axis and seawater adaptation of rainbow trout (Oncorhynchus mykiss)

USGS Publications Warehouse

Poppinga, J.; Kittilson, J.; McCormick, S.D.; Sheridan, M.A.

2007-01-01

Growth hormone (GH) has been shown to contribute to the seawater (SW) adaptability of euryhaline fish both directly and indirectly through insulin-like growth factor-1 (IGF-1). This study examined the role of somatostatin-14 (SS-14), a potent inhibitor of GH, on the GH-IGF-1 axis and seawater adaptation. Juvenile rainbow trout (Oncorhynchus mykiss) were injected intraperitoneally with SS-14 or saline and transferred to 20??ppt seawater. A slight elevation in plasma chloride levels was accompanied by significantly reduced gill Na+, K+-ATPase activity in SS-14-treated fish compared to control fish 12??h after SW transfer. Seawater increased hepatic mRNA levels of GH receptor 1 (GHR 1; 239%), GHR 2 (48%), and IGF-1 (103%) in control fish 12??h after transfer. Levels of GHR 1 (155%), GHR 2 (121%), IGF-1 (200%), IGF-1 receptor A (IGFR1A; 62%), and IGFR1B (157%) increased in the gills of control fish 12??h after transfer. SS-14 abolished or attenuated SW-induced changes in the expression of GHR, IGF-1, and IGFR mRNAs in liver and gill. These results indicate that SS-14 reduces seawater adaptability by inhibiting the GH-IGF-1 axis. ?? 2007 Elsevier B.V. All rights reserved.

Effects of particle size and adaptation duration on the digestible and metabolizable energy contents and digestibility of various chemical constituents in wheat for finishing pigs determined by the direct or indirect method.

PubMed

Fan, Yuanfang; Guo, Panpan; Yang, Yuyuan; Xia, Tian; Liu, Ling; Ma, Yongxi

2017-04-01

This experiment was conducted as a 3×2×2 factorial design to examine the effects of particle size (mean particle size of 331, 640, or 862 μm), evaluation method (direct vs indirect method) and adaptation duration (7 or 26 days) on the energy content and the apparent total tract digestibility (ATTD) of various chemical components in wheat when fed to finishing pigs. Forty-two barrows (Duroc×Landrace×Yorkshire) with an initial body weight of 63.0±0.8 kg were individually placed in metabolic cages and randomly allotted to 1 of 7 diets with 6 pigs fed each diet. For the indirect method, the pigs were fed either a corn-soybean meal based basal diet or diets in which 38.94% of the basal diet was substituted by wheat of the different particle sizes. In the direct method, the diets contained 97.34% wheat with the different particle sizes. For both the direct and indirect methods, the pigs were adapted to their diets for either 7 or 26 days. A reduction in particle size linearly increased the digestible energy (DE) and metabolizable energy (ME) contents as well as the ATTD of gross energy, crude protein, organic matter, ether extract (EE) and acid detergent fiber (ADF) (p<0.05), and had a trend to increase the ATTD of dry matter of wheat (p = 0.084). The DE, ME contents, and ATTD of gross energy, crude protein, dry matter and organic matter were higher (p<0.05) when determined by the direct method, but the ATTD of ADF, EE, and neutral detergent fiber were higher when determined by the indirect method (p<0.05). Prolongation of the adaption duration decreased the ATTD of neutral detergent fiber (p<0.05) and had a trend to increase the ATTD of EE (p = 0.061). There were no interactions between particle size and the duration of the adaptation duration. The ATTD of EE in wheat was influenced by a trend of interaction between method and adaptation duration (p = 0.074). The ATTD of ADF and EE in wheat was influenced by an interaction between evaluation method and wheat particle size such that there were linear equations (p<0.01) about ATTD of ADF and EE when determined by the direct method but quadratic equations (p = 0.073 and p = 0.088, respectively) about ATTD of ADF and EE when determined by the indirect method. Decreasing particle size can improve the DE and ME contents of wheat; both of the direct and indirect methods of evaluation are suitable for evaluating the DE and ME contents of wheat with different particle sizes; and an adaptation duration of 7 d is sufficient to evaluate DE and ME contents of wheat in finishing pigs.

Active Control Of Structure-Borne Noise

NASA Astrophysics Data System (ADS)

Elliott, S. J.

1994-11-01

The successful practical application of active noise control requires an understanding of both its acoustic limitations and the limitations of the electrical control strategy used. This paper is concerned with the active control of sound in enclosures. First, a review is presented of the fundamental physical limitations of using loudspeakers to achieve either global or local control. Both approaches are seen to have a high frequency limit, due to either the acoustic modal overlap, or the spatial correlation function of the pressure field. These physical performance limits could, in principle, be achieved with either a feedback or a feedforward control strategy. These strategies are reviewed and the use of adaptive digital filters is discussed for both approaches. The application of adaptive feedforward control in the control of engine and road noise in cars is described. Finally, an indirect approach to the active control of sound is discussed, in which the vibration is suppressed in the structural paths connecting the source of vibration to the enclosure. Two specific examples of this strategy are described, using an active automotive engine mount and the incorporation of actuators into helicopter struts to control gear-meshing tones. In both cases good passive design can minimize the complexity of the active controller.

Enhancing Cultural and Contextual Intervention Strategies to Reduce HIV/AIDS Among African Americans

PubMed Central

2009-01-01

I describe 4 protective strategies that African Americans employ that may challenge current HIV prevention efforts: (1) an adaptive duality that protects identity, (2) personal control influenced by external factors, (3) long-established indirect communication patterns, and (4) a mistrust of “outsiders.” I propose the Sexual Health Model as a conceptual framework for HIV prevention interventions because it incorporates established adaptive coping strategies into new HIV-related protective skills. The Sexual Health Model promotes interconnectedness, sexual ownership, and body awareness, 3 concepts that represent the context of the African American historical and cultural experience and that enhance rather than contradict future prevention efforts. PMID:19762666

Indirect evolutionary rescue: prey adapts, predator avoids extinction

PubMed Central

Yamamichi, Masato; Miner, Brooks E

2015-01-01

Recent studies have increasingly recognized evolutionary rescue (adaptive evolution that prevents extinction following environmental change) as an important process in evolutionary biology and conservation science. Researchers have concentrated on single species living in isolation, but populations in nature exist within communities of interacting species, so evolutionary rescue should also be investigated in a multispecies context. We argue that the persistence or extinction of a focal species can be determined solely by evolutionary change in an interacting species. We demonstrate that prey adaptive evolution can prevent predator extinction in two-species predator–prey models, and we derive the conditions under which this indirect evolutionary interaction is essential to prevent extinction following environmental change. A nonevolving predator can be rescued from extinction by adaptive evolution of its prey due to a trade-off for the prey between defense against predation and population growth rate. As prey typically have larger populations and shorter generations than their predators, prey evolution can be rapid and have profound effects on predator population dynamics. We suggest that this process, which we term ‘indirect evolutionary rescue’, has the potential to be critically important to the ecological and evolutionary responses of populations and communities to dramatic environmental change. PMID:26366196

Improvement of crop yield in dry environments: benchmarks, levels of organisation and the role of nitrogen.

PubMed

Sadras, V O; Richards, R A

2014-05-01

Crop yield in dry environments can be improved with complementary approaches including selecting for yield in the target environments, selecting for yield potential, and using indirect, trait- or genomic-based methods. This paper (i) outlines the achievements of direct selection for yield in improving drought adaptation, (ii) discusses the limitations of indirect approaches in the context of levels of organization, and (iii) emphasizes trade-offs and synergies between nitrogen nutrition and drought adaptation. Selection for yield in the water- and nitrogen-scarce environments of Australia improved wheat yield per unit transpiration at a rate of 0.12kg ha(-1) mm(-1) yr(-1); for indirect methods to be justified, they must return superior rates of improvement, achieve the same rate at lower cost or provide other cost-effective benefits, such as expanding the genetic basis for selection. Slow improvement of crop adaptation to water stress using indirect methods is partially related to issues of scale. Traits are thus classified into three broad groups: those that generally scale up from low levels of organization to the crop level (e.g. herbicide resistance), those that do not (e.g. grain yield), and traits that might scale up provided they are considered in a integrated manner with scientifically sound scaling assumptions, appropriate growing conditions, and screening techniques (e.g. stay green). Predicting the scalability of traits may help to set priorities in the investment of research efforts. Primary productivity in arid and semi-arid environments is simultaneously limited by water and nitrogen, but few attempts are made to target adaptation to water and nitrogen stress simultaneously. Case studies in wheat and soybean highlight biological links between improved nitrogen nutrition and drought adaptation.

Flatness-based adaptive fuzzy control of chaotic finance dynamics

NASA Astrophysics Data System (ADS)

Rigatos, G.; Siano, P.; Loia, V.; Tommasetti, A.; Troisi, O.

2017-11-01

A flatness-based adaptive fuzzy control is applied to the problem of stabilization of the dynamics of a chaotic finance system, describing interaction between the interest rate, the investment demand and the price exponent. By proving that the system is differentially flat and by applying differential flatness diffeomorphisms, its transformation to the linear canonical (Brunovsky) is performed. For the latter description of the system, the design of a stabilizing state feedback controller becomes possible. A first problem in the design of such a controller is that the dynamic model of the finance system is unknown and thus it has to be identified with the use neurofuzzy approximators. The estimated dynamics provided by the approximators is used in the computation of the control input, thus establishing an indirect adaptive control scheme. The learning rate of the approximators is chosen from the requirement the system's Lyapunov function to have always a negative first-order derivative. Another problem that has to be dealt with is that the control loop is implemented only with the use of output feedback. To estimate the non-measurable state vector elements of the finance system, a state observer is implemented in the control loop. The computation of the feedback control signal requires the solution of two algebraic Riccati equations at each iteration of the control algorithm. Lyapunov stability analysis demonstrates first that an H-infinity tracking performance criterion is satisfied. This signifies elevated robustness against modelling errors and external perturbations. Moreover, the global asymptotic stability is proven for the control loop.

A Controlled Study of the Effectiveness of an Adaptive Closed-Loop Algorithm to Minimize Corticosteroid-Induced Stress Hyperglycemia in Type 1 Diabetes

PubMed Central

Youssef, Joseph El; Castle, Jessica R; Branigan, Deborah L; Massoud, Ryan G; Breen, Matthew E; Jacobs, Peter G; Bequette, B Wayne; Ward, W Kenneth

2011-01-01

To be effective in type 1 diabetes, algorithms must be able to limit hyperglycemic excursions resulting from medical and emotional stress. We tested an algorithm that estimates insulin sensitivity at regular intervals and continually adjusts gain factors of a fading memory proportional-derivative (FMPD) algorithm. In order to assess whether the algorithm could appropriately adapt and limit the degree of hyperglycemia, we administered oral hydrocortisone repeatedly to create insulin resistance. We compared this indirect adaptive proportional-derivative (APD) algorithm to the FMPD algorithm, which used fixed gain parameters. Each subject with type 1 diabetes (n = 14) was studied on two occasions, each for 33 h. The APD algorithm consistently identified a fall in insulin sensitivity after hydrocortisone. The gain factors and insulin infusion rates were appropriately increased, leading to satisfactory glycemic control after adaptation (premeal glucose on day 2, 148 ± 6 mg/dl). After sufficient time was allowed for adaptation, the late postprandial glucose increment was significantly lower than when measured shortly after the onset of the steroid effect. In addition, during the controlled comparison, glycemia was significantly lower with the APD algorithm than with the FMPD algorithm. No increase in hypoglycemic frequency was found in the APD-only arm. An afferent system of duplicate amperometric sensors demonstrated a high degree of accuracy; the mean absolute relative difference of the sensor used to control the algorithm was 9.6 ± 0.5%. We conclude that an adaptive algorithm that frequently estimates insulin sensitivity and adjusts gain factors is capable of minimizing corticosteroid-induced stress hyperglycemia. PMID:22226248

A model of adaptation for families of elderly patients with dementia: focusing on family resilience.

PubMed

Kim, Geun Myun; Lim, Ji Young; Kim, Eun Joo; Kim, Sang Suk

2017-07-19

We constructed a model explaining families' positive adaptation in chronic crisis situations such as the problematic behavior of elderly patients with dementia and attendant caregiving stress, based on the family resilience model. Our aim was to devise an adaptation model for families of elderly patients with dementia. A survey of problematic behavior in elderly patients with dementia, family stress, family resilience, and family adaptation was conducted with 292 consenting individuals. The collected data were analyzed using structural equation modeling. The communication process, family stress, and problematic behavior of elderly patients with dementia had direct and indirect effects on family adaptation, while belief system, organization pattern, and social support had indirect effects. Specifically, family stress and more severe problematic behavior by elderly patients with dementia negatively influenced family adaptation, while greater family resilience improved such adaptation. Interventions aiming to enhance family resilience, based on the results of this study, are required to help families with positive adaptation. Such family programs might involve practical support such as education on the characteristics of elderly persons with dementia and coping methods for their problematic behavior; forming self-help groups for families; revitalizing communication within families; and activating communication channels with experts.

Marginal adaptation of CAD-CAM onlays: Influence of preparation design and impression technique.

PubMed

Lima, Fernanda Ferruzzi; Neto, Constantino Fernandes; Rubo, José H; Santos, Gildo Coelho; Moraes Coelho Santos, Maria Jacinta

2018-03-15

Factors that may affect the marginal adaptation of computer-aided design and computer-aided manufacturing (CAD-CAM) restorations include preparation design, impression technique, and CAD-CAM system. The influence of impression technique and preparation design on CAD-CAM partial coverage restorations has not been fully addressed. The purpose of this in vitro study was to investigate the influence of direct and indirect digital impression techniques and 2 preparation designs on the marginal adaptation of CAD-CAM onlays. Two mesio-occlusal buccal onlay preparations with reduction of the mesiobuccal cusp were made: conventional preparation (CP) with a 1.2-mm modified shoulder margin and modified preparation (MP) flat cuspal reduction without shoulder. Virtual models were generated from each preparation by using a digital scanner (BlueCam; Dentsply Sirona) from the plastic teeth (direct digital impression) or from the stone dies (indirect digital impression). Onlays were designed using a CAD-CAM system (CEREC 4.0; Dentsply Sirona), and nanoceramic resin blocks (Lava Ultimate Restorative; 3M ESPE) were milled using the CEREC MCX milling machine. Marginal discrepancy was evaluated using an optical stereomicroscope at ×25 magnification in 18 locations distributed along the margins of the preparation. The data were analyzed by using 3-way ANOVA followed by the Tukey HSD test (α=.05). CP presented a statistically significant reduced average marginal adaptation (59 ±50 μm) than did MP (69 ±58 μm) (P<.001). The Tukey HSD test showed the presence of a significantly larger marginal discrepancy in the mesial and buccal locations of MP when compared with CP. Regarding impression techniques, the buccal location presented the smallest average marginal discrepancy in restorations fabricated with indirect impression when compared with direct impression (42 ±33 μm and 60 ±39 μm) (P<.001). The results showed that conventional preparation with a modified shoulder margin presented improved marginal adaptation compared with modified preparation with flat cuspal reduction. Direct and indirect digital impression techniques produced restorations within a clinically acceptable range; however, the indirect impression technique resulted in the fabrication of restorations with superior marginal adaptation on the buccal location. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

History of Childhood Maltreatment and College Academic Outcomes: Indirect Effects of Hot Execution Function

PubMed Central

Welsh, Marilyn C.; Peterson, Eric; Jameson, Molly M.

2017-01-01

College students who report a history of childhood maltreatment may be at risk for poor outcomes. In the current study, we conducted an exploratory analysis to examine potential models that statistically mediate associations between aspects of maltreatment and aspects of academic outcome, with a particular focus on executive functions (EF). Consistent with contemporary EF research, we distinguished between relatively “cool” EF tasks (i.e., performed in a context relatively free of emotional or motivational valence) and “hot” EF tasks that emphasize performance under more emotionally arousing conditions. Sixty-one male and female college undergraduates self-reported childhood maltreatment history (emotional abuse and neglect, physical abuse and neglect, and sexual abuse) on the Childhood Trauma Questionnaire (CTQ), and were given two EF measures: (1) Go-No-Go (GNG) test that included a Color Condition (cool); Neutral Face Condition (warm); and Emotion Face condition (hot), and (2) Iowa Gambling Task (IGT), a measure of risky decision making that reflects hot EF. Academic outcomes were: (1) grade point average (GPA: first-semester, cumulative, and semester concurrent with testing), and (2) Student Adaptation to College Questionnaire (SACQ). Correlational patterns suggested two EF scores as potential mediators: GNG reaction time (RT) in the Neutral Face condition, and IGT Block 2 adaptive responding. Indirect effects analyses indicated that IGT Block 2 adaptive responding has an indirect effect on the relationship between CTQ Total score and 1st semester GPA, and between CTQ Emotional Abuse and concurrent GPA. Regarding college adaptation, we identified a consistent indirect effect of GNG Neutral Face RT on the relationship between CTQ Emotional Neglect and SACQ total, academic, social, and personal–emotional adaption scores. Our results demonstrate that higher scores on a child maltreatment history self-report negatively predict college academic outcomes as assessed by GPA and by self-reported adaptation. Further, relatively “hot” EF task performance on the IGT and GNG tasks serves as a link between child maltreatment experiences and college achievement and adaptation, suggesting that hot EF skills may be a fruitful direction for future intervention efforts to improve academic outcomes for this population. PMID:28725204

Physical discipline in Chinese American immigrant families: An adaptive culture perspective.

PubMed

Lau, Anna S

2010-07-01

Research on ethnic minority parenting has examined heritage cultural influences and contextual stressors on parenting processes. However, rarely are adaptive cultural processes considered, whereby ethnic minority parents bring their cultural values to bear in adapting to contextual demands in the host society. A survey of 107 Chinese American immigrant parents examined whether use of physical discipline can be predicted by cultural values, contextual stressors, and their interactions. Results indicated that distinct domains of cultural values were related to physical discipline in disparate ways, with some values decreasing risk and others indirectly increasing risk. There was some evidence that cultural values interacted with contextual stress to predict physical discipline. Parent-child acculturation conflicts were only related to physical discipline when parents held strong values about the importance of firm parental control. The findings illustrate how heritage cultural influences and current ecological demands may converge to shape parenting in immigrant families.

Ion Channels in Innate and Adaptive Immunity

PubMed Central

Feske, Stefan; Wulff, Heike; Skolnik, Edward Y.

2016-01-01

Ion channels and transporters mediate the transport of charged ions across hydrophobic lipid membranes. In immune cells, divalent cations such as calcium, magnesium, and zinc have important roles as second messengers to regulate intracellular signaling pathways. By contrast, monovalent cations such as sodium and potassium mainly regulate the membrane potential, which indirectly controls the influx of calcium and immune cell signaling. Studies investigating human patients with mutations in ion channels and transporters, analysis of gene-targeted mice, or pharmacological experiments with ion channel inhibitors have revealed important roles of ionic signals in lymphocyte development and in innate and adaptive immune responses. We here review the mechanisms underlying the function of ion channels and transporters in lymphocytes and innate immune cells and discuss their roles in lymphocyte development, adaptive and innate immune responses, and autoimmunity, as well as recent efforts to develop pharmacological inhibitors of ion channels for immunomodulatory therapy. PMID:25861976

Effects of climate change on forest vegetation [Chapter 6

Treesearch

Patrick N. Behrens; Robert E. Keane; David L. Peterson; Joanne J. Ho

2018-01-01

Projected rapid changes in climate will affect vegetation assemblages in the Intermountain Adaptation Partnership (IAP) region directly and indirectly. Direct effects include altered vegetation growth, mortality, and regeneration, and indirect effects include changes in disturbance regimes (Chapter 8) and interactions with altered ecosystem processes (e.g., hydrology,...

The Effect of Lighting on the Behavior of Children Who Are Developmentally Disabled.

ERIC Educational Resources Information Center

Shapiro, Michele; Roth, Dana; Marcus, Angela

2001-01-01

A study examined the behavior of 8 Israeli children (ages 2-4) with developmental disabilities and maladaptive behavior who were exposed to direct lighting with unshielded standard fluorescent lamps vs. indirect diffuse full spectrum fluorescent lamps. The duration of adaptive behaviors was significantly higher under the indirect lighting.…

Analytical solutions to optimal underactuated spacecraft formation reconfiguration

NASA Astrophysics Data System (ADS)

Huang, Xu; Yan, Ye; Zhou, Yang

2015-11-01

Underactuated systems can generally be defined as systems with fewer number of control inputs than that of the degrees of freedom to be controlled. In this paper, analytical solutions to optimal underactuated spacecraft formation reconfiguration without either the radial or the in-track control are derived. By using a linear dynamical model of underactuated spacecraft formation in circular orbits, controllability analysis is conducted for either underactuated case. Indirect optimization methods based on the minimum principle are then introduced to generate analytical solutions to optimal open-loop underactuated reconfiguration problems. Both fixed and free final conditions constraints are considered for either underactuated case and comparisons between these two final conditions indicate that the optimal control strategies with free final conditions require less control efforts than those with the fixed ones. Meanwhile, closed-loop adaptive sliding mode controllers for both underactuated cases are designed to guarantee optimal trajectory tracking in the presence of unmatched external perturbations, linearization errors, and system uncertainties. The adaptation laws are designed via a Lyapunov-based method to ensure the overall stability of the closed-loop system. The explicit expressions of the terminal convergent regions of each system states have also been obtained. Numerical simulations demonstrate the validity and feasibility of the proposed open-loop and closed-loop control schemes for optimal underactuated spacecraft formation reconfiguration in circular orbits.

Novel Fast Adapting Interneurons Mediate Cholinergic-Induced Fast GABAA IPSCs In Striatal Spiny Neurons

PubMed Central

Faust, Thomas W.; Assous, Maxime; Shah, Fulva; Tepper, James M.; Koós, Tibor

2015-01-01

Previous work suggests that neostriatal cholinergic interneurons control the activity of several classes of GABAergic interneurons through fast nicotinic receptor mediated synaptic inputs. Although indirect evidence has suggested the existence of several classes of interneurons controlled by this mechanism only one such cell type, the neuropeptide-Y expressing neurogliaform neuron, has been identified to date. Here we tested the hypothesis that in addition to the neurogliaform neurons that elicit slow GABAergic inhibitory responses, another interneuron type exists in the striatum that receives strong nicotinic cholinergic input and elicits conventional fast GABAergic synaptic responses in projection neurons. We obtained in vitro slice recordings from double transgenic mice in which Channelrhodopsin-2 was natively expressed in cholinergic neurons and a population of serotonin receptor-3a-Cre expressing GABAergic interneurons were visualized with tdTomato. We show that among the targeted GABAergic interneurons a novel type of interneuron, termed the fast-adapting interneuron, can be identified that is distinct from previously known interneurons based on immunocytochemical and electrophysiological criteria. We show using optogenetic activation of cholinergic inputs that fast-adapting interneurons receive a powerful supra-threshold nicotinic cholinergic input in vitro. Moreover, fast adapting neurons are densely connected to projection neurons and elicit fast, GABAA receptor mediated inhibitory postsynaptic responses. The nicotinic receptor mediated activation of fast-adapting interneurons may constitute an important mechanism through which cholinergic interneurons control the activity of projection neurons and perhaps the plasticity of their synaptic inputs when animals encounter reinforcing or otherwise salient stimuli. PMID:25865337

Global neural dynamic surface tracking control of strict-feedback systems with application to hypersonic flight vehicle.

PubMed

Xu, Bin; Yang, Chenguang; Pan, Yongping

2015-10-01

This paper studies both indirect and direct global neural control of strict-feedback systems in the presence of unknown dynamics, using the dynamic surface control (DSC) technique in a novel manner. A new switching mechanism is designed to combine an adaptive neural controller in the neural approximation domain, together with the robust controller that pulls the transient states back into the neural approximation domain from the outside. In comparison with the conventional control techniques, which could only achieve semiglobally uniformly ultimately bounded stability, the proposed control scheme guarantees all the signals in the closed-loop system are globally uniformly ultimately bounded, such that the conventional constraints on initial conditions of the neural control system can be relaxed. The simulation studies of hypersonic flight vehicle (HFV) are performed to demonstrate the effectiveness of the proposed global neural DSC design.

Plant adaptation or acclimation to rising CO2 ? Insight from first multigenerational RNA-Seq transcriptome.

PubMed

Watson-Lazowski, Alexander; Lin, Yunan; Miglietta, Franco; Edwards, Richard J; Chapman, Mark A; Taylor, Gail

2016-11-01

Atmospheric carbon dioxide (CO 2 ) directly determines the rate of plant photosynthesis and indirectly effects plant productivity and fitness and may therefore act as a selective pressure driving evolution, but evidence to support this contention is sparse. Using Plantago lanceolata L. seed collected from a naturally high CO 2 spring and adjacent ambient CO 2 control site, we investigated multigenerational response to future, elevated atmospheric CO 2 . Plants were grown in either ambient or elevated CO 2 (700 μmol mol -1 ), enabling for the first time, characterization of the functional and population genomics of plant acclimation and adaptation to elevated CO 2 . This revealed that spring and control plants differed significantly in phenotypic plasticity for traits underpinning fitness including above-ground biomass, leaf size, epidermal cell size and number and stomatal density and index. Gene expression responses to elevated CO 2 (acclimation) were modest [33-131 genes differentially expressed (DE)], whilst those between control and spring plants (adaptation) were considerably larger (689-853 DE genes). In contrast, population genomic analysis showed that genetic differentiation between spring and control plants was close to zero, with no fixed differences, suggesting that plants are adapted to their native CO 2 environment at the level of gene expression. An unusual phenotype of increased stomatal index in spring but not control plants in elevated CO 2 correlated with altered expression of stomatal patterning genes between spring and control plants for three loci (YODA, CDKB1;1 and SCRM2) and between ambient and elevated CO 2 for four loci (ER, YODA, MYB88 and BCA1). We propose that the two positive regulators of stomatal number (SCRM2) and CDKB1;1 when upregulated act as key controllers of stomatal adaptation to elevated CO 2 . Combined with significant transcriptome reprogramming of photosynthetic and dark respiration and enhanced growth in spring plants, we have identified the potential basis of plant adaptation to high CO 2 likely to occur over coming decades. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Adaptive functioning in pediatric epilepsy: contributions of seizure-related variables and parental anxiety.

PubMed

Kerne, Valerie; Chapieski, Lynn

2015-02-01

Young people with epilepsy are less likely to achieve the level of independence attained by their peers. We examined the seizure-related variables that placed a group of 97 pediatric patients with intractable seizures at risk for poor adaptive functioning. Analyses evaluated both the direct effects of the medical variables and indirect effects that were mediated through increased parental anxiety about their child's epilepsy. Higher numbers of anticonvulsants, presence of seizures that secondarily generalize, longer duration of seizure disorder, and younger age at onset were all identified as risk factors for poor adaptive functioning. Depending on the specific behavioral domain of adaptive functioning, the effects were sometimes direct and sometimes indirect. Lower levels of parental education and positive family history of seizures were associated with higher levels of parental anxiety. Interventions that target parental anxiety about seizures may mitigate the deleterious effects of epilepsy on social development. Copyright © 2014 Elsevier Inc. All rights reserved.

Mindful Attention Awareness Scale (MAAS): Psychometric properties of the French translation and exploration of its relations with emotion regulation strategies.

PubMed

Jermann, Françoise; Billieux, Joël; Larøi, Frank; d'Argembeau, Arnaud; Bondolfi, Guido; Zermatten, Ariane; Van der Linden, Martial

2009-12-01

Over the past few years, several questionnaires have been developed to measure mindfulness. The Mindful Attention Awareness Scale (MAAS) was created to specifically capture attention and awareness in daily life (Brown & Ryan, 2003). In this article, we present a French adaptation of the MAAS. In the 1st study, we explored the psychometric properties of this adaptation. In the 2nd study, we investigated its relation to cognitive emotion regulation and depressive symptomatology using path analysis. As in the original version of the MAAS, the French adaptation has a strong 1-factor structure. Moreover, there was a negative relationship between the MAAS and the severity of depressive symptoms, both directly and indirectly. The indirect pathway was mediated by the nonadaptive cognitive emotion regulation strategy of self-blame and the adaptive cognitive emotion regulation strategy of positive reappraisal. In conclusion, this questionnaire represents a valid mindfulness measure for French-speaking clinicians and researchers.

A cell biologist's perspective on physiological adaptation to opiate drugs.

PubMed

von Zastrow, Mark

2004-01-01

Opiate drugs such as morphine and heroin are among the most effective analgesics known but are also highly addictive. The clinical utility of opiates is limited by adaptive changes in the nervous system occurring after prolonged or repeated drug administration. These adaptations are believed to play an important role in the development of physiological tolerance and dependence to opiates, and to contribute to additional changes underlying the complex neurobehavioral syndrome of drug addiction. All of these adaptive changes are initiated by the binding of opiate drugs to a subfamily of G protein-coupled receptors that are also activated by endogenously produced opioid neuropeptides. It is increasingly evident that opiate-induced adaptations occur at multiple levels in the nervous system, beginning with regulation of opioid receptors themselves and extending to a complex network of direct and indirect modifications of "downstream" signaling machinery. Efforts in my laboratory are directed at understanding the biochemical and cell biological basis of opiate adaptations. So far, we have focused primarily on adaptations occurring at the level of opioid receptors themselves. These studies have contributed to defining a set of membrane trafficking mechanisms by which the number and functional activity of opioid receptors are controlled. The role of these mechanisms in affecting adaptation of "downstream" neurobiological substrates, and in mediating opiate-induced changes in whole-animal physiology and behavior, are exciting questions that are only beginning to be explored.

Interventional effects for mediation analysis with multiple mediators

PubMed Central

Vansteelandt, Stijn; Daniel, Rhian M.

2016-01-01

The mediation formula for the identification of natural (in)direct effects has facilitated mediation analyses that better respect the nature of the data, with greater consideration of the need for confounding control. The default assumptions on which it relies are strong, however. In particular, they are known to be violated when confounders of the mediator–outcome association are affected by the exposure. This complicates extensions of counterfactual-based mediation analysis to settings that involve repeatedly measured mediators, or multiple correlated mediators. VanderWeele, Vansteelandt, and Robins21 introduced so-called interventional (in)direct effects. These can be identified under much weaker conditions than natural (in)direct effects, but have the drawback of not adding up to the total effect. In this article, we adapt their proposal in order to achieve an exact decomposition of the total effect, and extend it to the multiple mediator setting. Interestingly, the proposed effects capture the path-specific effects of an exposure on an outcome that are mediated by distinct mediators, even when – as often – the structural dependence between the multiple mediators is unknown; for instance, when the direction of the causal effects between the mediators is unknown, or there may be unmeasured common causes of the mediators. PMID:27922534

Interventional Effects for Mediation Analysis with Multiple Mediators.

PubMed

Vansteelandt, Stijn; Daniel, Rhian M

2017-03-01

The mediation formula for the identification of natural (in)direct effects has facilitated mediation analyses that better respect the nature of the data, with greater consideration of the need for confounding control. The default assumptions on which it relies are strong, however. In particular, they are known to be violated when confounders of the mediator-outcome association are affected by the exposure. This complicates extensions of counterfactual-based mediation analysis to settings that involve repeatedly measured mediators, or multiple correlated mediators. VanderWeele, Vansteelandt, and Robins introduced so-called interventional (in)direct effects. These can be identified under much weaker conditions than natural (in)direct effects, but have the drawback of not adding up to the total effect. In this article, we adapt their proposal to achieve an exact decomposition of the total effect, and extend it to the multiple mediator setting. Interestingly, the proposed effects capture the path-specific effects of an exposure on an outcome that are mediated by distinct mediators, even when-as often-the structural dependence between the multiple mediators is unknown, for instance, when the direction of the causal effects between the mediators is unknown, or there may be unmeasured common causes of the mediators.

Controls for space structures

NASA Astrophysics Data System (ADS)

Balas, Mark

1991-11-01

Assembly and operation of large space structures (LSS) in orbit will require robot-assisted docking and berthing of partially-assembled structures. These operations require new solutions to the problems of controls. This is true because of large transient and persistent disturbances, controller-structure interaction with unmodeled modes, poorly known structure parameters, slow actuator/sensor dynamical behavior, and excitation of nonlinear structure vibrations during control and assembly. For on-orbit assembly, controllers must start with finite element models of LSS and adapt on line to the best operating points, without compromising stability. This is not easy to do, since there are often unmodeled dynamic interactions between the controller and the structure. The indirect adaptive controllers are based on parameter estimation. Due to the large number of modes in LSS, this approach leads to very high-order control schemes with consequent poor stability and performance. In contrast, direct model reference adaptive controllers operate to force the LSS to track the desirable behavior of a chosen model. These schemes produce simple control algorithms which are easy to implement on line. One problem with their use for LSS has been that the model must be the same dimension as the LSS - i.e., quite large. A control theory based on the command generator tracker (CGT) ideas of Sobel, Mabins, Kaufman and Wen, Balas to obtain very low-order models based on adaptive algorithms was developed. Closed-loop stability for both finite element models and distributed parameter models of LSS was proved. In addition, successful numerical simulations on several LSS databases were obtained. An adaptive controller based on our theory was also implemented on a flexible robotic manipulator at Martin Marietta Astronautics. Computation schemes for controller-structure interaction with unmodeled modes, the residual mode filters or RMF, were developed. The RMF theory was modified to compensate slow actuator/sensor dynamics. These new ideas are being applied to LSS simulations to demonstrate the ease with which one can incorporate slow actuator/sensor effects into our design. It was also shown that residual mode filter compensation can be modified for small nonlinearities to produce exponentially stable closed-loop control.

Controls for space structures

NASA Technical Reports Server (NTRS)

Balas, Mark

1991-01-01

Assembly and operation of large space structures (LSS) in orbit will require robot-assisted docking and berthing of partially-assembled structures. These operations require new solutions to the problems of controls. This is true because of large transient and persistent disturbances, controller-structure interaction with unmodeled modes, poorly known structure parameters, slow actuator/sensor dynamical behavior, and excitation of nonlinear structure vibrations during control and assembly. For on-orbit assembly, controllers must start with finite element models of LSS and adapt on line to the best operating points, without compromising stability. This is not easy to do, since there are often unmodeled dynamic interactions between the controller and the structure. The indirect adaptive controllers are based on parameter estimation. Due to the large number of modes in LSS, this approach leads to very high-order control schemes with consequent poor stability and performance. In contrast, direct model reference adaptive controllers operate to force the LSS to track the desirable behavior of a chosen model. These schemes produce simple control algorithms which are easy to implement on line. One problem with their use for LSS has been that the model must be the same dimension as the LSS - i.e., quite large. A control theory based on the command generator tracker (CGT) ideas of Sobel, Mabins, Kaufman and Wen, Balas to obtain very low-order models based on adaptive algorithms was developed. Closed-loop stability for both finite element models and distributed parameter models of LSS was proved. In addition, successful numerical simulations on several LSS databases were obtained. An adaptive controller based on our theory was also implemented on a flexible robotic manipulator at Martin Marietta Astronautics. Computation schemes for controller-structure interaction with unmodeled modes, the residual mode filters or RMF, were developed. The RMF theory was modified to compensate slow actuator/sensor dynamics. These new ideas are being applied to LSS simulations to demonstrate the ease with which one can incorporate slow actuator/sensor effects into our design. It was also shown that residual mode filter compensation can be modified for small nonlinearities to produce exponentially stable closed-loop control. A theory for disturbance accommodating controllers based on reduced order models of structures was developed, and stability results for these controllers in closed-loop with large-scale finite element models of structures were obtained.

When seeking influences believing and promotes posttraumatic adaptation.

PubMed

Smith, Andrew J; Donlon, Katharine; Anderson, Scott R; Hughes, Michael; Jones, Russell T

2015-01-01

Theory and evidence link social support processes and self-efficacy appraisals in the promotion of adaptation following traumatic events. Dynamic causal processes, however, have not been examined longitudinally or in the context of mass-violence. This study tested whether quantity of social support seeking indirectly reduced distress severity among student survivors of mass university shootings. Hypotheses specified that the indirect effects of social support seeking on distress severity would occur through positively influencing perceived social support and self-efficacy, and that these effects would emerge and become stronger as posttraumatic stress symptom severity increased. Path analysis via Mplus 7.2 was used to test the hypothesized moderated-serial-mediation model (conditional indirect effects). The sample (N=1191) consisted of students enrolled at Virginia Tech during the 16 April 2007 shootings. Data were collected via online surveys at two time points, 3-4 months and 1-year post-shootings. Hypotheses were supported, showing that the indirect effects of social support seeking on distress reduction occurred through perceived social support, which in turn influenced self-efficacy. These effects emerged and grew in strength as PTS severity increased. Clinical implications, including the need to consider contextual determinants of posttraumatic recovery, are discussed.

Commonalities between Disaster and Climate Change Risks for Health: A Theoretical Framework.

PubMed

Banwell, Nicola; Rutherford, Shannon; Mackey, Brendan; Street, Roger; Chu, Cordia

2018-03-16

Disasters and climate change have significant implications for human health worldwide. Both climate change and the climate-sensitive hazards that result in disasters, are discussed in terms of direct and indirect impacts on health. A growing body of literature has argued for the need to link disaster risk reduction and climate change adaptation. However, there is limited articulation of the commonalities between these health impacts. Understanding the shared risk pathways is an important starting point for developing joint strategies for adapting to, and reducing, health risks. Therefore, this article discusses the common aspects of direct and indirect health risks of climate change and climate-sensitive disasters. Based on this discussion a theoretical framework is presented for understanding these commonalities. As such, this article hopes to extend the current health impact frameworks and provide a platform for further research exploring opportunities for linked adaptation and risk reduction strategies.

Commonalities between Disaster and Climate Change Risks for Health: A Theoretical Framework

PubMed Central

Banwell, Nicola; Rutherford, Shannon; Mackey, Brendan; Street, Roger; Chu, Cordia

2018-01-01

Disasters and climate change have significant implications for human health worldwide. Both climate change and the climate-sensitive hazards that result in disasters, are discussed in terms of direct and indirect impacts on health. A growing body of literature has argued for the need to link disaster risk reduction and climate change adaptation. However, there is limited articulation of the commonalities between these health impacts. Understanding the shared risk pathways is an important starting point for developing joint strategies for adapting to, and reducing, health risks. Therefore, this article discusses the common aspects of direct and indirect health risks of climate change and climate-sensitive disasters. Based on this discussion a theoretical framework is presented for understanding these commonalities. As such, this article hopes to extend the current health impact frameworks and provide a platform for further research exploring opportunities for linked adaptation and risk reduction strategies. PMID:29547592

Accurate positioning of long, flexible ARM's (Articulated Robotic Manipulator)

NASA Technical Reports Server (NTRS)

Malachowski, Michael J.

1988-01-01

An articulated robotic manipulator (ARM) system is being designed for space applications. Work being done on a concept utilizing an infinitely stiff laser beam for position reference is summarized. The laser beam is projected along the segments of the ARM, and the position is sensed by the beam rider modules (BRM) mounted on the distal ends of the segments. The BRM concept is the heart of the system. It utilizes a combination of lateral displacements and rotational and distance measurement sensors. These determine the relative position of the two ends of the segments with respect to each other in six degrees of freedom. The BRM measurement devices contain microprocessor controlled data acquisition and active positioning components. An indirect adaptive controller is used to accurately control the position of the ARM.

Functional anatomy of gliding membrane muscles in the sugar glider (Petaurus breviceps).

PubMed

Endo, H; Yokokawa, K; Kurohmaru, M; Hayashi, Y

1998-02-01

In order to clarify the morphological adaptation for gliding behavior in the marsupial mammals, the gliding membrane muscles in the sugar glider (Petaurus breviceps) were observed. Unlike the styliform cartilage in flying squirrels, the sugar glider has a well-developed tibiocarpalis muscle in the most lateral area of the gliding membrane. The gliding membrane substantially consists of the humerodorsalis and tibioabdominalis muscle complex. We believe that the thick tibiocarpalis bundle and the humerodorsalis and tibioabdominalis muscle complex may serve as a membrane controller in the gliding behavior. A characteristic thin membranous structure between the cutaneous and deeper muscles was observed. In addition to the direct powerful control exerted by trunk and limb movement, we suggest that indirect power conduction by this thin membranous structure may contribute to gliding membrane control.

Examining the broader psychosocial effects of mass conflict on PTSD symptoms and functional impairment amongst West Papuan refugees resettled in Papua New Guinea (PNG).

PubMed

Tay, Alvin Kuowei; Rees, Susan; Chan, Jack; Kareth, Moses; Silove, Derrick

2015-05-01

Mass conflict and displacement erode the core psychosocial foundations of society, but there is a dearth of quantitative data examining the long-term mental health effects of these macrocosmic changes, particularly in relation to posttraumatic stress disorder (PTSD) symptoms. In 2013, we conducted a cross-sectional community study (n = 230) of West Papuan refugees residing in Port Moresby, Papua New Guinea, testing a moderated-mediation structural equation model of PTSD symptoms in which we examined relationships involving the psychosocial effects of mass conflict and displacement based on the Adaptation and Development after Persecution and Trauma (ADAPT) model, a trauma count (TC) of traumatic events (TEs) related to mass conflict, and a count index of current adversity (AC). A direct and an indirect path via AC led to PTSD symptoms. The ADAPT index exerted two effects on PTSD symptoms, an indirect effect via AC, and a moderating effect on TC. PTSD symptoms were directly associated with functional impairment. Although based on cross-sectional data, our findings provide support for a core prediction of the ADAPT model, that is, that undermining of the core psychosocial foundations of society brought about by mass conflict and displacement exerts an indirect and moderating influence on PTSD symptoms. The path model supports the importance of repairing the psychosocial pillars of society as a foundation for addressing trauma-related symptoms and promoting the functioning of refugees. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Theoretical Approach to Norm Ecosystems: Two Adaptive Architectures of Indirect Reciprocity Show Different Paths to the Evolution of Cooperation

NASA Astrophysics Data System (ADS)

Uchida, Satoshi; Yamamoto, Hitoshi; Okada, Isamu; Sasaki, Tatsuya

2018-02-01

Indirect reciprocity is one of the basic mechanisms to sustain mutual cooperation, by which beneficial acts are returned, not by the recipient, but by third parties. This mechanism relies on the ability of individuals to know the past actions of others, and to assess those actions. There are many different systems of assessing others, which can be interpreted as rudimentary social norms (i.e., views on what is “good” or “bad”). In this paper, impacts of different adaptive architectures, i.e., ways for individuals to adapt to environments, on indirect reciprocity are investigated. We examine two representative architectures: one based on replicator dynamics and the other on genetic algorithm. Different from the replicator dynamics, the genetic algorithm requires describing the mixture of all possible norms in the norm space under consideration. Therefore, we also propose an analytic method to study norm ecosystems in which all possible second order social norms potentially exist and compete. The analysis reveals that the different adaptive architectures show different paths to the evolution of cooperation. Especially we find that so called Stern-Judging, one of the best studied norms in the literature, exhibits distinct behaviors in both architectures. On one hand, in the replicator dynamics, Stern-Judging remains alive and gets a majority steadily when the population reaches a cooperative state. On the other hand, in the genetic algorithm, it gets a majority only temporarily and becomes extinct in the end.

Parent beliefs and children's social-behavioral functioning: the mediating role of parent-teacher relationships.

PubMed

Kim, Elizabeth Moorman; Sheridan, Susan M; Kwon, Kyongboon; Koziol, Natalie

2013-04-01

This research investigated whether parent-teacher relationship quality mediated the relation between parents' motivational beliefs and children's adaptive functioning and externalizing behaviors. The sample consisted of kindergarten through third-grade children with behavioral concerns (N=206). Parents reported on their motivational beliefs (i.e., role construction and efficacy), and teachers reported on the quality of their relationships with parents and children's adaptive functioning (i.e., social and adaptive skills) and externalizing behaviors. Results indicated that parents' motivational beliefs were related significantly and positively to children's adaptive functioning and negatively to children's externalizing behaviors. Parents' motivational beliefs were also significantly associated with enhanced parent-teacher relationship quality. There was a significant medium-sized indirect effect of parents' motivational beliefs on children's adaptive functioning through parent-teacher relationship quality (k(2)=.12) and a small indirect effect of parents' motivational beliefs on children's externalizing behaviors (k(2)=.05). This research suggests that parent-teacher relationship quality may be one mechanism by which the benefits of parents' motivational beliefs are transmitted to children. Copyright © 2013 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Fuel optimization for low-thrust Earth-Moon transfer via indirect optimal control

NASA Astrophysics Data System (ADS)

Pérez-Palau, Daniel; Epenoy, Richard

2018-02-01

The problem of designing low-energy transfers between the Earth and the Moon has attracted recently a major interest from the scientific community. In this paper, an indirect optimal control approach is used to determine minimum-fuel low-thrust transfers between a low Earth orbit and a Lunar orbit in the Sun-Earth-Moon Bicircular Restricted Four-Body Problem. First, the optimal control problem is formulated and its necessary optimality conditions are derived from Pontryagin's Maximum Principle. Then, two different solution methods are proposed to overcome the numerical difficulties arising from the huge sensitivity of the problem's state and costate equations. The first one consists in the use of continuation techniques. The second one is based on a massive exploration of the set of unknown variables appearing in the optimality conditions. The dimension of the search space is reduced by considering adapted variables leading to a reduction of the computational time. The trajectories found are classified in several families according to their shape, transfer duration and fuel expenditure. Finally, an analysis based on the dynamical structure provided by the invariant manifolds of the two underlying Circular Restricted Three-Body Problems, Earth-Moon and Sun-Earth is presented leading to a physical interpretation of the different families of trajectories.

Climate-driven disparities among ecological interactions threaten kelp forest persistence.

PubMed

Provost, Euan J; Kelaher, Brendan P; Dworjanyn, Symon A; Russell, Bayden D; Connell, Sean D; Ghedini, Giulia; Gillanders, Bronwyn M; Figueira, WillIAM; Coleman, Melinda A

2017-01-01

The combination of ocean warming and acidification brings an uncertain future to kelp forests that occupy the warmest parts of their range. These forests are not only subject to the direct negative effects of ocean climate change, but also to a combination of unknown indirect effects associated with changing ecological landscapes. Here, we used mesocosm experiments to test the direct effects of ocean warming and acidification on kelp biomass and photosynthetic health, as well as climate-driven disparities in indirect effects involving key consumers (urchins and rock lobsters) and competitors (algal turf). Elevated water temperature directly reduced kelp biomass, while their turf-forming competitors expanded in response to ocean acidification and declining kelp canopy. Elevated temperatures also increased growth of urchins and, concurrently, the rate at which they thinned kelp canopy. Rock lobsters, which are renowned for keeping urchin populations in check, indirectly intensified negative pressures on kelp by reducing their consumption of urchins in response to elevated temperature. Overall, these results suggest that kelp forests situated towards the low-latitude margins of their distribution will need to adapt to ocean warming in order to persist in the future. What is less certain is how such adaptation in kelps can occur in the face of intensifying consumptive (via ocean warming) and competitive (via ocean acidification) pressures that affect key ecological interactions associated with their persistence. If such indirect effects counter adaptation to changing climate, they may erode the stability of kelp forests and increase the probability of regime shifts from complex habitat-forming species to more simple habitats dominated by algal turfs. © 2016 John Wiley & Sons Ltd.

Similarities amid the difference: caregiving burden and adaptation outcomes in dyads of parents and their children with and without cerebral palsy.

PubMed

Carona, C; Crespo, C; Canavarro, M C

2013-03-01

This study had two main objectives: first, to examine the direct and indirect effects, via social support, of caregiving burden on the adaptation outcomes of children/adolescents with cerebral palsy and their parents; and second, to assess the invariance of such models in clinical vs. healthy subsamples. Participants were 210 dyads of children/adolescents and one of their parents (total N=420), divided in 93 dyads of children/adolescents with cerebral palsy and 117 dyads of children/adolescents with no medical diagnosis. Data on caregiving burden, social support and adaptation outcomes were obtained through self-report questionnaires. Caregiving burden was linked to parents and their children's psychological maladjustment and quality of life both directly (except for children's quality of life) and indirectly through social support. Findings were invariant across clinical and healthy subsamples. Caregiving burden may influence adaptation outcomes of children/adolescents with CP and their parents both directly and via their social support perceptions. These patterns are similar to those observed in typically developing children/adolescents. Copyright © 2012 Elsevier Ltd. All rights reserved.

Short-Term Adaptive Modification of Dynamic Ocular Accommodation

PubMed Central

Bharadwaj, Shrikant R.; Vedamurthy, Indu; Schor, Clifton M.

2009-01-01

Purpose Indirect observations suggest that the neural control of accommodation may undergo adaptive recalibration in response to age-related biomechanical changes in the accommodative system. However, there has been no direct demonstration of such an adaptive capability. This investigation was conducted to demonstrate short-term adaptation of accommodative step response dynamics to optically induced changes in neuromuscular demands. Methods Repetitive changes in accommodative effort were induced in 15 subjects (18–34 years) with a double-step adaptation paradigm wherein an initial 2-D step change in blur was followed 350 ms later by either a 2-D step increase in blur (increasing-step paradigm) or a 1.75-D step decrease in blur (decreasing-step paradigm). Peak velocity, peak acceleration, and latency of 2-D single-step test responses were assessed before and after 1.5 hours of training with these paradigms. Results Peak velocity and peak acceleration of 2-D step responses increased after adaptation to the increasing-step paradigm (9/12 subjects), and they decreased after adaptation to the decreasing-step paradigm (4/9 subjects). Adaptive changes in peak velocity and peak acceleration generalized to responses that were smaller (1 D) and larger (3 D) than the 2-D adaptation stimulus. The magnitude of adaptation correlated poorly with the subject's age, but it was significantly negatively correlated with the preadaptation dynamics. Response latency decreased after adaptation, irrespective of the direction of adaptation. Conclusions Short-term adaptive changes in accommodative step response dynamics could be induced, at least in some of our subjects between 18 and 34 years, with a directional bias toward increasing rather than decreasing the dynamics. PMID:19255153

Assessment Study of the State of the Art in Adaptive Control and its Applications to Aircraft Control

NASA Technical Reports Server (NTRS)

Kaufman, Howard

1998-01-01

Many papers relevant to reconfigurable flight control have appeared over the past fifteen years. In general these have consisted of theoretical issues, simulation experiments, and in some cases, actual flight tests. Results indicate that reconfiguration of flight controls is certainly feasible for a wide class of failures. However many of the proposed procedures although quite attractive, need further analytical and experimental studies for meaningful validation. Many procedures assume the availability of failure detection and identification logic that will supply adequately fast, the dynamics corresponding to the failed aircraft. This in general implies that the failure detection and fault identification logic must have access to all possible anticipated faults and the corresponding dynamical equations of motion. Unless some sort of explicit on line parameter identification is included, the computational demands could possibly be too excessive. This suggests the need for some form of adaptive control, either by itself as the prime procedure for control reconfiguration or in conjunction with the failure detection logic. If explicit or indirect adaptive control is used, then it is important that the identified models be such that the corresponding computed controls deliver adequate performance to the actual aircraft. Unknown changes in trim should be modelled, and parameter identification needs to be adequately insensitive to noise and at the same time capable of tracking abrupt changes. If however, both failure detection and system parameter identification turn out to be too time consuming in an emergency situation, then the concepts of direct adaptive control should be considered. If direct model reference adaptive control is to be used (on a linear model) with stability assurances, then a positive real or passivity condition needs to be satisfied for all possible configurations. This condition is often satisfied with a feedforward compensator around the plant. This compensator must be robustly designed such that the compensated plant satisfies the required positive real conditions over all expected parameter values. Furthermore, with the feedforward only around the plant, a nonzero (but bounded error) will exist in steady state between the plant and model outputs. This error can be removed by placing the compensator also in the reference model. Design of such a compensator should not be too difficult a problem since for flight control it is generally possible to feedback all the system states.

The Strong African American Families program: longitudinal pathways to sexual risk reduction.

PubMed

Murry, Velma McBride; Berkel, Cady; Brody, Gene H; Gerrard, Meg; Gibbons, Meg; Gibbons, Frederick X

2007-10-01

To identify the mechanisms by which intervention-induced increases in adaptive parenting were associated with a reduction in sexual risk behavior among rural African American adolescents across a 29-month period. African American families (N = 284) with 11-year-old children in nine rural Georgian counties participated in the 7-week Strong African American Families (SAAF) project. Counties were randomly assigned to intervention or control conditions. The program was evaluated via pretest, posttest, and long-term follow-up interview data collected in the families' homes. The current paper tests a hypothetical model of program efficacy, positing that intervention-induced changes in parenting behaviors would enhance in youth self-pride, which in turn would forecast changes in sexual behaviors measured 29 months after pretest. Compared with controls, parents who participated in SAAF reported increased adaptive universal and racially specific parenting. Furthermore, intervention-induced changes in these parenting behaviors were associated indirectly with sexual risk behavior through adolescent self-pride, peer orientation, and sexual intent. Culturally competent programs, developed through empirical and theoretical research within affected communities, can foster adaptive universal and racially specific parenting, which can have a long-term effect on adolescent sexual risk behavior. Effective strategies for designing and implementing culturally competent programs are discussed.

Motivation-focused thinking: Buffering against stress-related physical symptoms and depressive symptomology.

PubMed

Hamm, Jeremy M; Perry, Raymond P; Chipperfield, Judith G; Stewart, Tara L; Heckhausen, Jutta

2015-01-01

Developmental transitions are experienced throughout the life course and necessitate adapting to consequential and unpredictable changes that can undermine health. Our six-month study (n = 239) explored whether selective secondary control striving (motivation-focused thinking) protects against the elevated levels of stress and depressive symptoms increasingly common to young adults navigating the challenging school-to-university transition. Path analyses supplemented with tests of moderated mediation revealed that, for young adults who face challenging obstacles to goal attainment, selective secondary control indirectly reduced long-term stress-related physical and depressive symptoms through selective primary control and previously unexamined measures of discrete emotions. Results advance the existing literature by demonstrating that (a) selective secondary control has health benefits for vulnerable young adults and (b) these benefits are largely a consequence of the process variables proposed in Heckhausen et al.'s (2010) theory.

Fuzzy wavelet plus a quantum neural network as a design base for power system stability enhancement.

PubMed

Ganjefar, Soheil; Tofighi, Morteza; Karami, Hamidreza

2015-11-01

In this study, we introduce an indirect adaptive fuzzy wavelet neural controller (IAFWNC) as a power system stabilizer to damp inter-area modes of oscillations in a multi-machine power system. Quantum computing is an efficient method for improving the computational efficiency of neural networks, so we developed an identifier based on a quantum neural network (QNN) to train the IAFWNC in the proposed scheme. All of the controller parameters are tuned online based on the Lyapunov stability theory to guarantee the closed-loop stability. A two-machine, two-area power system equipped with a static synchronous series compensator as a series flexible ac transmission system was used to demonstrate the effectiveness of the proposed controller. The simulation and experimental results demonstrated that the proposed IAFWNC scheme can achieve favorable control performance. Copyright © 2015 Elsevier Ltd. All rights reserved.

Popularity and Resource Control Goals as Predictors of Adolescent Indirect Aggression.

PubMed

Dyches, Karmon D; Mayeux, Lara

2015-01-01

Resource Control Theory conceptualizes aggression as a behavior that allows access to, and control of, limited resources (P. H. Hawley, 1999 ). This study investigated the associations of adolescents' indirect aggression with their resource control goals, or goals related to controlling social resources such as dating opportunities and peer status, and with their levels of popularity and social intelligence. Participants were 109 seventh-graders (52% girls) who completed a resource control goals measure, the Tromsø Social Intelligence Scale, and peer nominations of popularity and indirect aggression. Results indicated positive associations between resource control goals and peer-nominated indirect aggression, with popularity further moderating these associations. These findings suggest that the resource control goals of adolescents can be a motivating force to engage in hurtful behaviors. They provide a context from which peer relations researchers can improve their understanding and prevention of adolescents' indirect aggression.

Impacts of Organizational Knowledge Sharing Practices on Employees' Job Satisfaction: Mediating Roles of Learning Commitment and Interpersonal Adaptability

ERIC Educational Resources Information Center

Malik, Muhammad Shaukat; Kanwal, Maria

2018-01-01

Purpose: The purpose of this paper is to investigate empirically impacts of organizational knowledge-sharing practices (KSP) on employees' job satisfaction (JS), interpersonal adaptability (IA) and learning commitment (LC). Indirect effects of KSP on JS are also confirmed through mediating factors (LC and IA). Design/methodology/approach:…

Water quality-scarcity relationships in irrigated agriculture: Health risks and adaptation strategies associated with indirect wastewater reuse

NASA Astrophysics Data System (ADS)

Thebo, A.

2016-12-01

Urban wastewater provides a reliable, nutrient rich source of irrigation water for downstream agricultural producers. However, globally, less than ten percent of collected wastewater receives any form of treatment, resulting in the widespread indirect reuse of untreated, diluted wastewater from surface water sources. This research explores these links between water scarcity, anthropogenic drivers of water quality, and adaptation strategies farmer's employ through a case study in Dharwad, a mid-sized South Indian city. This study took an interdisciplinary approach, incorporating survey based research with geospatial analysis, and molecular methods (for waterborne pathogen detection) to develop a systems level understanding of the drivers, health risks, and adaptation strategies associated with the indirect reuse of wastewater in irrigated agriculture. In Dharwad, farmers with better access to wastewater reported growing more water-intensive, but higher value vegetable crops. While farmers further downstream tended to grow more staple crops. This study evaluated levels of culturable E. coli and diarrheagenic E. coli pathotype gene targets to assess contamination in irrigation water, soil, and on produce from farms. Irrigation water source was a major factor affecting the concentrations of culturable E. coli detected in soil samples and on greens. However, even when irrigation water was not contaminated (all borewell water samples) some culturable E. coli were present at low concentrations in soil and on produce samples, suggesting additional sources of contamination on farms. Maximum temperatures within the previous week showed a significant positive association with concentrations of E. coli on wastewater irrigated produce. This presentation will focus on discussing the ways in which urban wastewater management, climate, irrigation practices and cultivation patterns all come together to define the risks and benefits posed via the indirect reuse of wastewater.

GENERALIZATION OF TREADMILL-SLIP TRAINING TO PREVENT A FALL FOLLLOWING A SUDDEN (NOVEL) SLIP IN OVER-GROUND WALKING

PubMed Central

Yang, Feng; Bhatt, Tanvi; Pai, Yi-Chung

2012-01-01

The purposes of the study were to determine 1) whether treadmill-slip training could reduce the likelihood of falls during a novel slip in over-ground walking, and 2) to what extent such (indirect) training would be comparable to (direct) over-ground-slip training. A treadmill-slip training group (Group A, n=17) initially experienced repeated perturbations on treadmill intended to simulate forward-slip in over-ground walking. Perturbation continued and its intensity reduced when necessary to ensure subjects’ successful adaptation (i.e., when they could land their trailing foot ahead of the slipping foot in at least 3 of 5 consecutive trials). They then experienced a novel slip during over-ground walking. Another 17 young adults in Group B experienced an identical novel slip that served as the controls. They then underwent more slip trials during over-ground walking. Their 16th slip trial was analyzed to represent the over-ground-slip training effect. Eight subjects (47%) in Group A fell upon their first treadmill slip, while all adapted successfully after a minimum of 15 slip trials. Upon the novel slip during over-ground walking, none of them fell in comparison to four subjects (23.5%) fell in Group B upon the same trial (p<0.05). Group A’s control of stability, both proactive and reactive, was significantly better than that of Group B’s on their first over-ground slip, while the level of improvement derived from indirect treadmill training was not as strong as that from direct over-ground-slip training, as demonstrated in Group B’s 16th slip trial (p<0.001). These results clearly demonstrated the feasibility of fall reduction through treadmill-slip training. PMID:23141636

Can We Improve Structured Sequence Processing? Exploring the Direct and Indirect Effects of Computerized Training Using a Mediational Model

PubMed Central

Smith, Gretchen N. L.; Conway, Christopher M.; Bauernschmidt, Althea; Pisoni, David B.

2015-01-01

Recent research suggests that language acquisition may rely on domain-general learning abilities, such as structured sequence processing, which is the ability to extract, encode, and represent structured patterns in a temporal sequence. If structured sequence processing supports language, then it may be possible to improve language function by enhancing this foundational learning ability. The goal of the present study was to use a novel computerized training task as a means to better understand the relationship between structured sequence processing and language function. Participants first were assessed on pre-training tasks to provide baseline behavioral measures of structured sequence processing and language abilities. Participants were then quasi-randomly assigned to either a treatment group involving adaptive structured visuospatial sequence training, a treatment group involving adaptive non-structured visuospatial sequence training, or a control group. Following four days of sequence training, all participants were assessed with the same pre-training measures. Overall comparison of the post-training means revealed no group differences. However, in order to examine the potential relations between sequence training, structured sequence processing, and language ability, we used a mediation analysis that showed two competing effects. In the indirect effect, adaptive sequence training with structural regularities had a positive impact on structured sequence processing performance, which in turn had a positive impact on language processing. This finding not only identifies a potential novel intervention to treat language impairments but also may be the first demonstration that structured sequence processing can be improved and that this, in turn, has an impact on language processing. However, in the direct effect, adaptive sequence training with structural regularities had a direct negative impact on language processing. This unexpected finding suggests that adaptive training with structural regularities might potentially interfere with language processing. Taken together, these findings underscore the importance of pursuing designs that promote a better understanding of the mechanisms underlying training-related changes, so that regimens can be developed that help reduce these types of negative effects while simultaneously maximizing the benefits to outcome measures of interest. PMID:25946222

Can we improve structured sequence processing? Exploring the direct and indirect effects of computerized training using a mediational model.

PubMed

Smith, Gretchen N L; Conway, Christopher M; Bauernschmidt, Althea; Pisoni, David B

2015-01-01

Recent research suggests that language acquisition may rely on domain-general learning abilities, such as structured sequence processing, which is the ability to extract, encode, and represent structured patterns in a temporal sequence. If structured sequence processing supports language, then it may be possible to improve language function by enhancing this foundational learning ability. The goal of the present study was to use a novel computerized training task as a means to better understand the relationship between structured sequence processing and language function. Participants first were assessed on pre-training tasks to provide baseline behavioral measures of structured sequence processing and language abilities. Participants were then quasi-randomly assigned to either a treatment group involving adaptive structured visuospatial sequence training, a treatment group involving adaptive non-structured visuospatial sequence training, or a control group. Following four days of sequence training, all participants were assessed with the same pre-training measures. Overall comparison of the post-training means revealed no group differences. However, in order to examine the potential relations between sequence training, structured sequence processing, and language ability, we used a mediation analysis that showed two competing effects. In the indirect effect, adaptive sequence training with structural regularities had a positive impact on structured sequence processing performance, which in turn had a positive impact on language processing. This finding not only identifies a potential novel intervention to treat language impairments but also may be the first demonstration that structured sequence processing can be improved and that this, in turn, has an impact on language processing. However, in the direct effect, adaptive sequence training with structural regularities had a direct negative impact on language processing. This unexpected finding suggests that adaptive training with structural regularities might potentially interfere with language processing. Taken together, these findings underscore the importance of pursuing designs that promote a better understanding of the mechanisms underlying training-related changes, so that regimens can be developed that help reduce these types of negative effects while simultaneously maximizing the benefits to outcome measures of interest.

Testing Direct and Indirect Effects of Sports Participation on Perceived Health in Spanish Adolescents between 15 and 18 Years of Age

ERIC Educational Resources Information Center

Pastor, Yolanda; Balaguer, Isabel; Pons, Diana; Garcia-Merita, Marisa

2003-01-01

This paper examines the direct and indirect effects of sports participation on perceived health. It is based on a representative sample of middle adolescents aged 15-18 (N=1038, M AGE=16.31, S. D.=0.92; 510 boys and 528 girls) from the Valencian Community (Spain). This study used two different models; Model A is an adaptation of Thorlindsson,…

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2013 CFR

2013-01-01

... 12 Banks and Banking 3 2013-01-01 2013-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Companies Interpretations § 225.112 Indirect control of small business concern through convertible...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2014 CFR

2014-01-01

... 12 Banks and Banking 3 2014-01-01 2014-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Companies Interpretations § 225.112 Indirect control of small business concern through convertible...

78 FR 39352 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing of Proposed Rule Change Relating...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-01

... provide that, so long as ICE Group directly or indirectly controls any U.S. Regulated Subsidiary, the... indirectly controls any U.S. Regulated Subsidiary, the books, records and premises of ICE Group will be... Group directly or indirectly controls any Regulated Subsidiary (as defined in the NYSE Group Certificate...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Interpretations § 225.112 Indirect control of small business concern through convertible debentures held by small...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2011 CFR

2011-01-01

... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Interpretations § 225.112 Indirect control of small business concern through convertible debentures held by small...

12 CFR 225.112 - Indirect control of small business concern through convertible debentures held by small business...

Code of Federal Regulations, 2012 CFR

2012-01-01

... 12 Banks and Banking 3 2012-01-01 2012-01-01 false Indirect control of small business concern through convertible debentures held by small business investment company. 225.112 Section 225.112 Banks... Interpretations § 225.112 Indirect control of small business concern through convertible debentures held by small...

Similarities amid the Difference: Caregiving Burden and Adaptation Outcomes in Dyads of Parents and Their Children with and without Cerebral Palsy

ERIC Educational Resources Information Center

Carona, C.; Crespo, C.; Canavarro, M. C.

2013-01-01

This study had two main objectives: first, to examine the direct and indirect effects, via social support, of caregiving burden on the adaptation outcomes of children/adolescents with cerebral palsy and their parents; and second, to assess the invariance of such models in clinical vs. healthy subsamples. Participants were 210 dyads of…

Haloperidol Selectively Remodels Striatal Indirect Pathway Circuits

PubMed Central

Sebel, Luke E; Graves, Steven M; Chan, C Savio; Surmeier, D James

2017-01-01

Typical antipsychotic drugs are widely thought to alleviate the positive symptoms of schizophrenia by antagonizing dopamine D2 receptors expressed by striatal spiny projection neurons (SPNs). What is less clear is why antipsychotics have a therapeutic latency of weeks. Using a combination of physiological and anatomical approaches in ex vivo brain slices from transgenic mice, it was found that 2 weeks of haloperidol treatment induced both intrinsic and synaptic adaptations specifically within indirect pathway SPNs (iSPNs). Perphenazine treatment had similar effects. Some of these adaptations were homeostatic, including a drop in intrinsic excitability and pruning of excitatory corticostriatal glutamatergic synapses. However, haloperidol treatment also led to strengthening of a subset of excitatory corticostriatal synapses. This slow remodeling of corticostriatal iSPN circuitry is likely to play a role in mediating the delayed therapeutic action of neuroleptics. PMID:27577602

Spatial adaptation of the cortical visual evoked potential of the cat.

PubMed

Bonds, A B

1984-06-01

Adaptation that is spatially specific for the adapting pattern has been seen psychophysically in humans. This is indirect evidence for independent analyzers (putatively single units) that are specific for orientation and spatial frequency in the human visual system, but it is unclear how global adaptation characteristics may be related to single unit performance. Spatially specific adaptation was sought in the cat visual evoked potential (VEP), with a view towards relating this phenomenon with what we know of cat single units. Adaptation to sine-wave gratings results in a temporary loss of cat VEP amplitude, with induction and recovery similar to that seen in human psychophysical experiments. The amplitude loss was specific for both the spatial frequency and orientation of the adapting pattern. The bandwidth of adaptation was not unlike the average selectivity of a population of cat single units.

Animal health aspects of adaptation to climate change: beating the heat and parasites in a warming Europe.

PubMed

Skuce, P J; Morgan, E R; van Dijk, J; Mitchell, M

2013-06-01

Weather patterns in northern European regions have changed noticeably over the past several decades, featuring warmer, wetter weather with more extreme events. The climate is projected to continue on this trajectory for the foreseeable future, even under the most modest warming scenarios. Such changes will have a significant impact on livestock farming, both directly through effects on the animals themselves, and indirectly through changing exposure to pests and pathogens. Adaptation options aimed at taking advantage of new opportunities and/or minimising the risks of negative impacts will, in themselves, have implications for animal health and welfare. In this review, we consider the potential consequences of future intensification of animal production, challenges associated with indoor and outdoor rearing of animals and aspects of animal transportation as key examples. We investigate the direct and indirect effects of climate change on the epidemiology of important livestock pathogens, with a particular focus on parasitic infections, and the likely animal health consequences associated with selected adaptation options. Finally, we attempt to identify key gaps in our knowledge and suggest future research priorities.

Climate change, wine, and conservation.

PubMed

Hannah, Lee; Roehrdanz, Patrick R; Ikegami, Makihiko; Shepard, Anderson V; Shaw, M Rebecca; Tabor, Gary; Zhi, Lu; Marquet, Pablo A; Hijmans, Robert J

2013-04-23

Climate change is expected to impact ecosystems directly, such as through shifting climatic controls on species ranges, and indirectly, for example through changes in human land use that may result in habitat loss. Shifting patterns of agricultural production in response to climate change have received little attention as a potential impact pathway for ecosystems. Wine grape production provides a good test case for measuring indirect impacts mediated by changes in agriculture, because viticulture is sensitive to climate and is concentrated in Mediterranean climate regions that are global biodiversity hotspots. Here we demonstrate that, on a global scale, the impacts of climate change on viticultural suitability are substantial, leading to possible conservation conflicts in land use and freshwater ecosystems. Area suitable for viticulture decreases 25% to 73% in major wine producing regions by 2050 in the higher RCP 8.5 concentration pathway and 19% to 62% in the lower RCP 4.5. Climate change may cause establishment of vineyards at higher elevations that will increase impacts on upland ecosystems and may lead to conversion of natural vegetation as production shifts to higher latitudes in areas such as western North America. Attempts to maintain wine grape productivity and quality in the face of warming may be associated with increased water use for irrigation and to cool grapes through misting or sprinkling, creating potential for freshwater conservation impacts. Agricultural adaptation and conservation efforts are needed that anticipate these multiple possible indirect effects.

God image and happiness in chronic pain patients: the mediating role of disease interpretation.

PubMed

Dezutter, Jessie; Luyckx, Koen; Schaap-Jonker, Hanneke; Büssing, Arndt; Corveleyn, Jozef; Hutsebaut, Dirk

2010-05-01

The present study explored the role of the emotional experience of God (i.e., positive and negative God images) in the happiness of chronic pain (CP) patients. Framed in the transactional model of stress, we tested a model in which God images would influence happiness partially through its influence on disease interpretation as a mediating mechanism. We expected God images to have both a direct and an indirect (through the interpretation of disease) effect on happiness. A cross-sectional questionnaire design was adopted in order to measure demographics, pain condition, God images, disease interpretation, and happiness. One hundred thirty-six CP patients, all members of a national patients' association, completed the questionnaires. Correlational analyses showed meaningful associations among God images, disease interpretation, and happiness. Path analyses from a structural equation modeling approach indicated that positive God images seemed to influence happiness, both directly and indirectly through the pathway of positive interpretation of the disease. Ancillary analyses showed that the negative influence of angry God images on happiness disappeared after controlling for pain severity. The results indicated that one's emotional experience of God has an influence on happiness in CP patients, both directly and indirectly through the pathway of positive disease interpretation. These findings can be framed within the transactional theory of stress and can stimulate further pain research investigating the possible effects of religion in the adaptation to CP.

Climate change, wine, and conservation

PubMed Central

Hannah, Lee; Roehrdanz, Patrick R.; Ikegami, Makihiko; Shepard, Anderson V.; Shaw, M. Rebecca; Tabor, Gary; Zhi, Lu; Marquet, Pablo A.; Hijmans, Robert J.

2013-01-01

Climate change is expected to impact ecosystems directly, such as through shifting climatic controls on species ranges, and indirectly, for example through changes in human land use that may result in habitat loss. Shifting patterns of agricultural production in response to climate change have received little attention as a potential impact pathway for ecosystems. Wine grape production provides a good test case for measuring indirect impacts mediated by changes in agriculture, because viticulture is sensitive to climate and is concentrated in Mediterranean climate regions that are global biodiversity hotspots. Here we demonstrate that, on a global scale, the impacts of climate change on viticultural suitability are substantial, leading to possible conservation conflicts in land use and freshwater ecosystems. Area suitable for viticulture decreases 25% to 73% in major wine producing regions by 2050 in the higher RCP 8.5 concentration pathway and 19% to 62% in the lower RCP 4.5. Climate change may cause establishment of vineyards at higher elevations that will increase impacts on upland ecosystems and may lead to conversion of natural vegetation as production shifts to higher latitudes in areas such as western North America. Attempts to maintain wine grape productivity and quality in the face of warming may be associated with increased water use for irrigation and to cool grapes through misting or sprinkling, creating potential for freshwater conservation impacts. Agricultural adaptation and conservation efforts are needed that anticipate these multiple possible indirect effects. PMID:23569231

Influence of Visual Prism Adaptation on Auditory Space Representation.

PubMed

Pochopien, Klaudia; Fahle, Manfred

2017-01-01

Prisms shifting the visual input sideways produce a mismatch between the visual versus felt position of one's hand. Prism adaptation eliminates this mismatch, realigning hand proprioception with visual input. Whether this realignment concerns exclusively the visuo-(hand)motor system or it generalizes to acoustic inputs is controversial. We here show that there is indeed a slight influence of visual adaptation on the perceived direction of acoustic sources. However, this shift in perceived auditory direction can be fully explained by a subconscious head rotation during prism exposure and by changes in arm proprioception. Hence, prism adaptation does only indirectly generalize to auditory space perception.

Does age affect the stress and coping process? Implications of age differences in perceived control.

PubMed

Aldwin, C M

1991-07-01

The perceived controllability of situations is thought to influence the types of coping strategies used, and thus is important in adaptive processes. Elderly individuals are widely perceived to have less control over their environment than other adults. This lack of perceived control should have adverse affects on how they cope with stressful situations. However, most studies have shown that older adults differ little from younger adults in their approaches to coping with stress. This contradiction was investigated in a sample of 228 community-residing adults with a mean age of 42.16 (SD = 14.88). Path analysis revealed that appraisals and attributions do affect the use of coping strategies such as instrumental action and escapism in the expected directions, and age is negatively associated with perceived control. However, there was an independent and negative relationship between age and the reported use of escapist coping strategies, which mitigated the adverse effects of perceived lack of control. Neither age nor perceived controllability had direct effects on depression, but they had indirect effects through their influence on the use of coping strategies and perceived efficacy.

Seaweed Bioactive Compounds against Pathogens and Microalgae: Potential Uses on Pharmacology and Harmful Algae Bloom Control.

PubMed

Zerrifi, Soukaina El Amrani; El Khalloufi, Fatima; Oudra, Brahim; Vasconcelos, Vitor

2018-02-09

Cyanobacteria are found globally due to their adaptation to various environments. The occurrence of cyanobacterial blooms is not a new phenomenon. The bloom-forming and toxin-producing species have been a persistent nuisance all over the world over the last decades. Evidence suggests that this trend might be attributed to a complex interplay of direct and indirect anthropogenic influences. To control cyanobacterial blooms, various strategies, including physical, chemical, and biological methods have been proposed. Nevertheless, the use of those strategies is usually not effective. The isolation of natural compounds from many aquatic and terrestrial plants and seaweeds has become an alternative approach for controlling harmful algae in aquatic systems. Seaweeds have received attention from scientists because of their bioactive compounds with antibacterial, antifungal, anti-microalgae, and antioxidant properties. The undesirable effects of cyanobacteria proliferations and potential control methods are here reviewed, focusing on the use of potent bioactive compounds, isolated from seaweeds, against microalgae and cyanobacteria growth.

Seaweed Bioactive Compounds against Pathogens and Microalgae: Potential Uses on Pharmacology and Harmful Algae Bloom Control

PubMed Central

Zerrifi, Soukaina El Amrani; El Khalloufi, Fatima; Oudra, Brahim; Vasconcelos, Vitor

2018-01-01

Cyanobacteria are found globally due to their adaptation to various environments. The occurrence of cyanobacterial blooms is not a new phenomenon. The bloom-forming and toxin-producing species have been a persistent nuisance all over the world over the last decades. Evidence suggests that this trend might be attributed to a complex interplay of direct and indirect anthropogenic influences. To control cyanobacterial blooms, various strategies, including physical, chemical, and biological methods have been proposed. Nevertheless, the use of those strategies is usually not effective. The isolation of natural compounds from many aquatic and terrestrial plants and seaweeds has become an alternative approach for controlling harmful algae in aquatic systems. Seaweeds have received attention from scientists because of their bioactive compounds with antibacterial, antifungal, anti-microalgae, and antioxidant properties. The undesirable effects of cyanobacteria proliferations and potential control methods are here reviewed, focusing on the use of potent bioactive compounds, isolated from seaweeds, against microalgae and cyanobacteria growth. PMID:29425153

Microgravity and Cellular Consequences in Lymphocyte Function

NASA Technical Reports Server (NTRS)

Pellis, Neal R.; Sundaresan, Alamelu

2004-01-01

Mammalian cells adapt to the environment of low gravity and express a series of responses, some possibly from direct effects on cells and others based on environmental conditions created by microgravity. Human lymphocytes in microgravity culture are functionally diminished in activation and locomotion. Both processes are integral to optimal immune response to fight pathogens. The NASA Rotating-wall vessel (RWV) is a well-accepted analog for microgravity culture on the ground. Gene array experiments and immunoblotting identified upstream events in human lymphocytes adapting to microgravity analog culture. Microgravity induces selective changes, many of which are cell membrane related. Results showed that upstream of PKC in the T cell activation cascade, PLC-gamma and LAT are significantly diminished. ZAP 70 which controls LAT activation is also down regulated in modeled microgravity. Thus events governing cell shape might warrant attention in microgravity conditions. The goal of this study is to delineate response suites that are consequential, direct or indirect effects of the microgravity environment and which of these are essential to lymphocytes

Parenting and Coregulation: Adaptive Systems for Competence in Children Experiencing Homelessness

PubMed Central

Herbers, Janette E.; Cutuli, J. J.; Supkoff, Laura M.; Narayan, Angela J.; Masten, Ann S.

2018-01-01

The role of effective parenting in promoting child executive functioning and school success was examined among 138 children (age 4 to 6 years) staying in family emergency shelters the summer before kindergarten or first grade. Parent-child coregulation, which refers to relationship processes wherein parents guide and respond to the behavior of their children, was observed during structured interaction tasks and quantified as a dyadic construct using state space grid methodology. Positive coregulation was related to children’s executive functioning and IQ, which in turn were related to teacher-reported outcomes once school began. Separate models considering parenting behavior demonstrated that EF carried indirect effects of parents’ directive control to school outcomes. Meanwhile, responsive parenting behaviors directly predicted children’s peer acceptance at school beyond effects of EF and IQ. Findings support theory and past research in developmental science indicating the importance of effective parenting in shaping positive adaptive skills among children who overcome adversity, in part through processes of coregulation. PMID:24999527

Evaluating the Use of an Electronic Death Registration System for Mortality Surveillance During and After Hurricane Sandy: New York City, 2012

PubMed Central

Li, Wenhui; Madsen, Ann M.; Wong, Howard; Das, Tara; Betancourt, Flor M.; Nicaj, Leze; Stayton, Catherine; Matte, Thomas; Begier, Elizabeth M.

2015-01-01

Objectives. We evaluated the use of New York City’s (NYC’s) electronic death registration system (EDRS) to conduct mortality surveillance during and after Hurricane Sandy. Methods. We used Centers for Disease Control and Prevention guidelines for surveillance system evaluation to gather evidence on usefulness, flexibility, stability, timeliness, and quality. We assessed system components, interviewed NYC Health Department staff, and analyzed 2010 to 2012 death records. Results. Despite widespread disruptions, NYC’s EDRS was stable and collected timely mortality data that were adapted to provide storm surveillance with minimal additional resources. Direct-injury fatalities and trends in excess all-cause mortality were rapidly identified, providing useful information for response; however, the time and burden of establishing reports, adapting the system, and identifying indirect deaths limited surveillance. Conclusions. The NYC Health Department successfully adapted its EDRS for near real-time disaster-related mortality surveillance. Retrospective assessment of deaths, advanced methods for case identification and analysis, standardized reports, and system enhancements will further improve surveillance. Local, state, and federal partners would benefit from partnering with vital records to develop EDRSs for surveillance and to promote ongoing evaluation. PMID:26378834

Climate warming alters effects of management on population viability of threatened species: results from a 30-year experimental study on a rare orchid.

PubMed

Sletvold, Nina; Dahlgren, Johan P; Oien, Dag-Inge; Moen, Asbjørn; Ehrlén, Johan

2013-09-01

Climate change is expected to influence the viability of populations both directly and indirectly, via species interactions. The effects of large-scale climate change are also likely to interact with local habitat conditions. Management actions designed to preserve threatened species therefore need to adapt both to the prevailing climate and local conditions. Yet, few studies have separated the direct and indirect effects of climatic variables on the viability of local populations and discussed the implications for optimal management. We used 30 years of demographic data to estimate the simultaneous effects of management practice and among-year variation in four climatic variables on individual survival, growth and fecundity in one coastal and one inland population of the perennial orchid Dactylorhiza lapponica in Norway. Current management, mowing, is expected to reduce competitive interactions. Statistical models of how climate and management practice influenced vital rates were incorporated into matrix population models to quantify effects on population growth rate. Effects of climate differed between mown and control plots in both populations. In particular, population growth rate increased more strongly with summer temperature in mown plots than in control plots. Population growth rate declined with spring temperature in the inland population, and with precipitation in the coastal population, and the decline was stronger in control plots in both populations. These results illustrate that both direct and indirect effects of climate change are important for population viability and that net effects depend both on local abiotic conditions and on biotic conditions in terms of management practice and intensity of competition. The results also show that effects of management practices influencing competitive interactions can strongly depend on climatic factors. We conclude that interactions between climate and management should be considered to reliably predict future population viability and optimize conservation actions. © 2013 John Wiley & Sons Ltd.

Control methods and systems for indirect evaporative coolers

DOEpatents

Woods, Jason; Kozubal, Erik

2015-09-22

A control method for operating an indirect evaporative cooler to control temperature and humidity. The method includes operating an airflow control device to provide supply air at a flow rate to a liquid desiccant dehumidifier. The supply air flows through the dehumidifier and an indirect evaporative cooler prior to exiting an outlet into a space. The method includes operating a pump to provide liquid desiccant to the liquid desiccant dehumidifier and sensing a temperature of an airstream at the outlet of the indirect evaporative cooler. The method includes comparing the temperature of the airstream at the outlet to a setpoint temperature at the outlet and controlling the pump to set the flow rate of the liquid desiccant. The method includes sensing space temperature, comparing the space temperature with a setpoint temperature, and controlling the airflow control device to set the flow rate of the supply air based on the comparison.

Top-down control of serotonin systems by the prefrontal cortex: a path towards restored socioemotional function in depression

PubMed Central

Challis, Collin; Berton, Olivier

2015-01-01

Social withdrawal, increased threat perception and exaggerated reassurance seeking behaviors are prominent interpersonal symptoms in major depressive disorder (MDD). Altered serotonin (5-HT) systems and corticolimbic dysconnectivity have long been suspected to contribute to these symptomatic facets, however, the underlying circuits and intrinsic cellular mechanisms that control 5-HT output during socioemotional interactions remain poorly understood. We review literature that implicates a direct pathway between the ventromedial prefrontal cortex (vmPFC) and dorsal raphe nucleus (DRN) in the adaptive and pathological control of social approach-avoidance behaviors. Imaging and neuromodulation during approach-avoidance tasks in humans point to the cortical control of brainstem circuits as an essential regulator of socioemotional decisions and actions. Parallel rodent studies using viral-based connectomics and optogenetics are beginning to provide a cellular blueprint of the underlying circuitry. In these studies, manipulations of vmPFC synaptic inputs to the DRN have revealed bidirectional influences on socioaffective behaviors via direct monosynaptic excitation and indirect disynaptic inhibition of 5-HT neurons. Additionally, adverse social experiences that result in permanent avoidance biases, such as social defeat, drive long-lasting plasticity in this microcircuit, potentiating the indirect inhibition of 5-HT output. Conversely, neuromodulation of the vmPFC via deep brain stimulation (DBS) attenuates avoidance biases by restoring the direct excitatory drive of 5-HT neurons and strengthening a key subset of forebrain 5-HT projections. Better understanding the cellular organization of the vmPFC-DRN pathway and identifying molecular determinants of its neuroplasticity can open fundamentally novel avenues for the treatment of affective disorders. PMID:25706226

Practical diagnostic testing for human immunodeficiency virus.

PubMed Central

Jackson, J B; Balfour, H H

1988-01-01

Since the discovery of human immunodeficiency virus (HIV) as the causative agent of acquired immunodeficiency syndrome in 1983, there has been a proliferation of diagnostic tests. These assays can be used to detect the presence of HIV antibody, HIV antigen, HIV ribonucleic and deoxyribonucleic acids, and HIV reverse transcriptase. Enzyme-linked immunosorbent assays, Western blot, radioimmunoprecipitation assays, indirect immunofluorescence assays, reverse transcriptase assays, and several molecular hybridization techniques are currently available. Enzyme-linked immunosorbent, Western blot, and indirect immunofluorescence assays for HIV antibody are very sensitive, specific, and adaptable to most laboratories. An enzyme-linked immunosorbent assay for HIV antigen is also readily adaptable to most laboratories and will be commercially available soon. While the other assays are more tedious, they are valuable confirmatory tests and are suitable for reference laboratories. The biohazards of performing HIV testing can be minimized with proper biosafety measures. Images PMID:3060241

Indirect Measurement of Sexual Orientation: Comparison of the Implicit Relational Assessment Procedure, Viewing Time, and Choice Reaction Time Tasks.

PubMed

Rönspies, Jelena; Schmidt, Alexander F; Melnikova, Anna; Krumova, Rosina; Zolfagari, Asadeh; Banse, Rainer

2015-07-01

The present study was conducted to validate an adaptation of the Implicit Relational Assessment Procedure (IRAP) as an indirect latency-based measure of sexual orientation. Furthermore, reliability and criterion validity of the IRAP were compared to two established indirect measures of sexual orientation: a Choice Reaction Time task (CRT) and a Viewing Time (VT) task. A sample of 87 heterosexual and 35 gay men completed all three indirect measures in an online study. The IRAP and the VT predicted sexual orientation nearly perfectly. Both measures also showed a considerable amount of convergent validity. Reliabilities (internal consistencies) reached satisfactory levels. In contrast, the CRT did not tap into sexual orientation in the present study. In sum, the VT measure performed best, with the IRAP showing only slightly lower reliability and criterion validity, whereas the CRT did not yield any evidence of reliability or criterion validity in the present research. The results were discussed in the light of specific task properties of the indirect latency-based measures (task-relevance vs. task-irrelevance).

Immunity to human cytomegalovirus measured and compared by complement fixation, indirect fluorescent-antibody, indirect hemagglutination, and enzyme-linked immunosorbent assays.

PubMed Central

Brandt, J A; Kettering, J D; Lewis, J E

1984-01-01

The complement fixation test is currently the test employed most frequently to determine the presence of antibody to human cytomegalovirus. Several other techniques have been adapted for this purpose. A comparison of cytomegalovirus antibody titers was made between the complement fixation test, a commercially available enzyme-linked immunosorbent assay, an indirect immunofluorescent technique, and a modified indirect hemagglutination test. Forty-three serum samples were tested for antibodies by each of the above procedures. The enzyme-linked immunosorbent, immunofluorescent, and indirect hemagglutination assays were in close agreement on all samples tested; the titers obtained with these methods were all equal to or greater than the complement fixation titer for 38 of the 41 samples (92.6%). Two samples were anticomplementary in the complement fixation test but gave readable results in the other tests. The complement fixation test was the least sensitive of the procedures examined. The commercial enzyme-linked immunosorbent assay system was the most practical method and offered the highest degree of sensitivity in detecting antibodies to cytomegalovirus. PMID:6321544

Developmentally adapted cognitive processing therapy for adolescents and young adults with PTSD symptoms after physical and sexual abuse: study protocol for a randomized controlled trial.

PubMed

Rosner, Rita; König, Hans-Helmut; Neuner, Frank; Schmidt, Ulrike; Steil, Regina

2014-05-29

Although childhood sexual and/or physical abuse (CSA/CPA) is known to have severe psychopathological consequences, there is little evidence on psychotherapeutic interventions for adolescents and young adults suffering from post-traumatic stress disorder (PTSD). Equally sparse are data on moderators of treatment response on PTSD-related epigenetic changes, health care costs and loss of productivity, alterations in cognitive processing, and on how successful interventions affect all of these factors. Early treatment may prevent later (co)morbidity. In this paper, we present a study protocol for the evaluation of a newly developed psychotherapeutic manual for PTSD after CSA/CPA in adolescents and young adults - the Developmentally Adapted Cognitive Processing Therapy (D-CPT). In a multicenter randomized controlled trial (RCT) D-CPT is compared to treatment as usual (TAU). A sample of 90 adolescent outpatients aged 14 to 21 years will be randomized to one of these conditions. Four assessments will be carried out at baseline, at end of treatment, and 3 and 6 months after end of therapy. Each time, patients will be assessed via clinical interviews and a wide range of questionnaires. In addition to PTSD symptoms and comorbidities, we will evaluate moderators of treatment response, epigenetic profiles, direct and indirect costs of this disorder, and neurophysiological processing of threat cues in PTSD and their respective changes in the course of these two treatments (D-CPT and TAU). The study will provide new insights in the understudied field of PTSD in adolescents and young adults. A newly developed intervention will be evaluated in this therapeutically underserved population. Results will provide data on treatment efficacy, direct and indirect treatment costs, as well as on associations of treatment outcome and PTSD intensity both to epigenetic profiles and to the neurobiological processing of threat cues. Besides, they will help to learn more about the psychopathology and possible new objective correlates of PTSD. Germanctr.de identifier: DRKS00004787.

The Immunology of Posttransplant CMV Infection: Potential Effect of CMV Immunoglobulins on Distinct Components of the Immune Response to CMV

PubMed Central

Carbone, Javier

2016-01-01

Abstract The immune response to cytomegalovirus (CMV) infection is highly complex, including humoral, cellular, innate, and adaptive immune responses. Detection of CMV by the innate immune system triggers production of type I IFNs and inflammatory cytokines which initiate cellular and humoral responses that are critical during the early viremic phase of CMV infection. Sustained control of CMV infection is largely accounted for by cellular immunity, involving various T-cell and B-cell subsets. In solid organ transplant patients, global suppression of innate and adaptive immunities by immunosuppressive agents limits immunological defense, including inhibition of natural killer cell activity with ongoing lowering of Ig levels and CMV-specific antibody titers. This is coupled with a short-term suppression of CMV-specific T cells, the extent and duration of which can predict risk of progression to CMV viremia. CMV immunoglobulin (CMVIG) preparations have the potential to exert immunomodulatory effects as well as providing passive immunization. Specific CMVIG antibodies and virus neutralization might be enhanced by modulation of dendritic cell activity and by a decrease in T-cell activation, effects which are of importance during the initial phase of infection. In summary, the role of CMVIG in reconstituting specific anti-CMV antibodies may be enhanced by some degree of modulation of the innate and adaptive immune responses, which could help to control some of the direct and indirect effects of CMV infection. PMID:26900990

Evolution of temporal order in living organisms

PubMed Central

Paranjpe, Dhanashree A; Sharma, Vijay Kumar

2005-01-01

Circadian clocks are believed to have evolved in parallel with the geological history of the earth, and have since been fine-tuned under selection pressures imposed by cyclic factors in the environment. These clocks regulate a wide variety of behavioral and metabolic processes in many life forms. They enhance the fitness of organisms by improving their ability to efficiently anticipate periodic events in their external environments, especially periodic changes in light, temperature and humidity. Circadian clocks provide fitness advantage even to organisms living under constant conditions, such as those prevailing in the depth of oceans or in subterranean caves, perhaps by coordinating several metabolic processes in the internal milieu. Although the issue of adaptive significance of circadian rhythms has always remained central to circadian biology research, it has never been subjected to systematic and rigorous empirical validation. A few studies carried out on free-living animals under field conditions and simulated periodic and aperiodic conditions of the laboratory suggest that circadian rhythms are of adaptive value to their owners. However, most of these studies suffer from a number of drawbacks such as lack of population-level replication, lack of true controls and lack of adequate control on the genetic composition of the populations, which in many ways limits the potential insights gained from the studies. The present review is an effort to critically discuss studies that directly or indirectly touch upon the issue of adaptive significance of circadian rhythms and highlight some shortcomings that should be avoided while designing future experiments. PMID:15869714

The Immunology of Posttransplant CMV Infection: Potential Effect of CMV Immunoglobulins on Distinct Components of the Immune Response to CMV.

PubMed

Carbone, Javier

2016-03-01

The immune response to cytomegalovirus (CMV) infection is highly complex, including humoral, cellular, innate, and adaptive immune responses. Detection of CMV by the innate immune system triggers production of type I IFNs and inflammatory cytokines which initiate cellular and humoral responses that are critical during the early viremic phase of CMV infection. Sustained control of CMV infection is largely accounted for by cellular immunity, involving various T-cell and B-cell subsets. In solid organ transplant patients, global suppression of innate and adaptive immunities by immunosuppressive agents limits immunological defense, including inhibition of natural killer cell activity with ongoing lowering of Ig levels and CMV-specific antibody titers. This is coupled with a short-term suppression of CMV-specific T cells, the extent and duration of which can predict risk of progression to CMV viremia. CMV immunoglobulin (CMVIG) preparations have the potential to exert immunomodulatory effects as well as providing passive immunization. Specific CMVIG antibodies and virus neutralization might be enhanced by modulation of dendritic cell activity and by a decrease in T-cell activation, effects which are of importance during the initial phase of infection. In summary, the role of CMVIG in reconstituting specific anti-CMV antibodies may be enhanced by some degree of modulation of the innate and adaptive immune responses, which could help to control some of the direct and indirect effects of CMV infection.

Apperception of Clouds in AIRS Data

NASA Technical Reports Server (NTRS)

Huang, Hung-Lung; Smith, William L.

2005-01-01

Our capacity to simulate the radiative characteristics of the Earth system has advanced greatly over the past decade. However, new space based measurements show that idealized simulations might not adequately represent the complexity of nature. For example, AIRS simulated multi-layer cloud clearing research provides an excellent groundwork for early Atmospheric Infra-Red Sounder (AIRS) operational cloud clearing and atmospheric profile retrieval. However, it doesn't reflect the complicated reality of clouds over land and coastal areas. Thus far, operational AIRS/AMSU (Advanced Microwave Sounding Unit) cloud clearing is not only of low yield but also of unsatisfying quality. This is not an argument for avoiding this challenging task, rather a powerful argument for exploring other synergistic approaches, and for adapting these strategies toward improving both indirect and direct use of cloudy infrared sounding data. Ample evidence is shown in this paper that the indirect use of cloudy sounding data by way of cloud clearing is sub-optimal for data assimilation. Improvements are needed in quality control, retrieval yield, and overall cloud clearing retrieval performance. For example, cloud clearing over land, especially over the desert surface, has led to much degraded retrieval quality and often a very low yield of quality controlled cloud cleared radiances. If these indirect cloud cleared radiances are instead to be directly assimilated into NWP models, great caution must be used. Our limited and preliminary cloud clearing results from AIRS/AMSU (with the use of MODIS data) and an AIRS/MODIS synergistic approach have, however, shown that higher spatial resolution multispectral imagery data can provide much needed quality control of the AIRS/AMSU cloud clearing retrieval. When AIRS and Moderate Resolution Imaging Spectroradiometer (MODIS) are used synergistically, a higher spatial resolution over difficult terrain (especially desert areas) can be achieved and with a much improved accuracy. Preliminary statistical analyses of cloud cleared radiances derived from (1) operational AIRS/AMSU, (2) operational AIRS/AMSU plus the use of MODIS data as quality control, and (3) AIRS/MODIS synergistic single channel and two field of views cloud clearing are Our capacity to simulate the radiative characteristics of the Earth system has

Lateral cascade of indirect effects in food webs with different types of adaptive behavior.

PubMed

Kamran-Disfani, Ahmad R; Golubski, Antonio J

2013-12-21

It is widely recognized that indirect effects due to adaptive behaviors can have important effects on food webs. One consequence may be to change how readily perturbations propagate through the web, because species' behaviors as well as densities may respond to perturbations. It is not well understood which types of behavior are more likely to facilitate versus inhibit propagation of disturbances through a food web, or how this might be affected by the shape of a food web or the patterns of interaction strengths within it. We model two simple, laterally expanded food webs (one with three trophic levels and one with four), and compare how various adaptive behaviors affect the potential for a newly introduced predator to change the equilibrium densities of distant species. Patterns of changes in response to the introduction were qualitatively similar across most models, as were the ways in which patterns of direct interaction strengths affected those responses. Depending on both the web structure and the specific adaptive behavior, the potential for density changes to propagate through the web could be either increased or diminished relative to the no-behavior model. Two behaviors allowed density changes to propagate through a four-level web that precluded such propagation in the no-behavior model, and each of these two behaviors led to qualitatively different patterns of density changes. In the one model (diet choice) in which density changes were able to propagate in both web structures, patterns of density changes differed qualitatively between webs. Some of our results flowed from the fact that behaviors did not interact directly in the systems we considered, so that indirect effects on distant species had to be at least partly density-mediated. Our models highlight this as an inherent limitation of considering in isolation behaviors that are strictly foraging-related or strictly defense-related, making a case for the value of simultaneously considering multiple interacting types of behavior in the same model. Copyright © 2013 Elsevier Ltd. All rights reserved.

The effect of perceived stress on the relationship between perfectionism and burnout in coaches.

PubMed

Tashman, Lauren S; Tenenbaum, Gershon; Eklund, Robert

2010-01-01

The effects of perceived stress (PS) on the relationship between adaptive and maladaptive forms of perfectionism and burnout were examined. Smith's (1986)stress appraisal model and Kelley, Eklund, and Ritter-Taylor's (1999) model of coach burnout were used to test two models of burnout in a sample of college coaches (N=177). The results indicated that there is an indirect effect of self-evaluative perfectionism (i.e., maladaptive form of perfectionism) on burnout through PS as well as a significant direct link to burnout, accounting for 56% of its variance. In contrast, conscientious perfectionism (CP) (i.e., adaptive perfectionism) did not directly impact burnout, nor was there an indirect effect through PS. Based on Lazarus's (1999) ideas about stress appraisal, the results suggested that maladaptive forms of perfectionism resulted in more threatening perceptions of stress, thus, potentially leading to the experience of burnout. However, adaptive forms of perfectionism did not seem to result in increased appraisals of stress or result in burnout. The results did indicate a significant correlation between the two forms of perfectionism, which may explain why CP did not significantly impact PS or burnout.

Vegetation regulation on streamflow intra-annual variability through adaption to climate variations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Sheng; Li, Hongyi; Li, Shuai

2015-12-16

This study aims to provide a mechanistic explanation of the empirical patterns of streamflow intra-annual variability revealed by watershed-scale hydrological data across the contiguous United States. A mathematical extension of the Budyko formula with explicit account for the soil moisture storage change is used to show that, in catchments with a strong seasonal coupling between precipitation and potential evaporation, climate aridity has a dominant control on intra-annual streamflow variability, but in other catchments, additional factors related to soil water storage change also have important controls on how precipitation seasonality propagates to streamflow. More importantly, use of leaf area index asmore » a direct and indirect indicator of the above ground biomass and plant root system, respectively, reveals the vital role of vegetation in regulating soil moisture storage and hence streamflow intra-annual variability under different climate conditions.« less

Margin adaptation of indirect composite inlays fabricated on flexible dies.

PubMed

Price, R B; Gerrow, J D

2000-03-01

Indirect composite restorations can be made in 1 appointment using a flexible die. Interactions between different impression materials and flexible die materials may affect the accuracy of fit and margin adaptation of the restoration. This study compared the margin adaptation of composite inlays made using the following 5 impression/flexible die material combinations; condensation silicone/polyvinyl siloxane (CS/PVS), wash viscosity polyvinyl siloxane/medium or heavy viscosity polyvinyl siloxane (PVS/PVS), irreversible hydrocolloid impression/medium viscosity polyvinyl siloxane (IH/PVS), wash viscosity polyvinyl siloxane impression/polyether (PVS/PE), with composite inlays made using a control system of a wash viscosity polyvinyl siloxane impression and a type IV stone die. For each test and control system, 10 impressions were made of a class II composite inlay preparation in a metal master die. One die was made from each impression and one composite inlay was made and finished on each die (a total of 60 inlays). Inlays were placed on the master die and the margin opening at the buccal, distal, and gingival sites was recorded with a measuring microscope (x40 magnification). The overall mean +/- SD margin openings of inlays made from the systems were as follows: PVS wash/PVS heavy viscosity 149.5 +/- 107. 4 microm; PVS wash/PVS medium viscosity 87.4 +/- 63.0 microm; IH/PVS medium viscosity 76.7 +/- 48.9 microm; CS/PVS 73.3 +/- 48.7 microm, PVS wash viscosity/PE 64.0 +/- 44.3 microm, PVS wash viscosity/stone 53.9 +/- 48.3 microm. Composite inlays made using the PVS wash viscosity/PVS heavy viscosity system had significantly larger distal, gingival, and overall mean margin openings than all other inlays (ANOVA and Fisher PLSD test; P =.05). The separating medium required between some impression and die materials did not work consistently. Composite inlays fabricated on dies made of material different than the impression material had mean buccal, distal, gingival, and overall margin openings < or =100 microm. Composite inlays made on the CS/PVS, IH/PVS medium viscosity, PVS wash viscosity/PE flexible dies, and control PVS wash viscosity/stone dies had statistically similar (P =.05) mean buccal, distal, gingival, and overall mean margin openings that were < or =100 microm. Composite inlays made on dies that were made of the same type of material as the impression material (PVS/PVS) had mean gingival margin openings >100 microm that were significantly larger than all other systems tested (P =.05).

Experience using individually supplied heater rods in critical power testing of advanced BWR fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Majed, M.; Morback, G.; Wiman, P.

1995-09-01

The ABB Atom FRIGG loop located in Vasteras Sweden has during the last six years given a large experience of critical power measurements for BWR fuel designs using indirectly heated rods with individual power supply. The loop was built in the sixties and designed for maximum 100 bar pressure. Testing up to the mid eighties was performed with directly heated rods using a 9 MW, 80 kA power supply. Providing test data to develop critical power correlations for BWR fuel assemblies requires testing with many radial power distributions over the full range of hydraulic conditions. Indirectly heated rods give largemore » advantages for the testing procedure, particularly convenient for variation of individual rod power. A test method being used at Stern Laboratories (formerly Westinghouse Canada) since the early sixties, allows one fuel assembly to simulate all required radial power distributions. This technique requires reliable indirectly heated rods with independently controlled power supplies and uses insulated electric fuel rod simulators with built-in instrumentation. The FRIGG loop was adapted to this system in 1987. A 4MW power supply with 10 individual units was then installed, and has since been used for testing 24 and 25 rod bundles simulating one subbundle of SVEA-96/100 type fuel assemblies. The experience with the system is very good, as being presented, and it is selected also for a planned upgrading of the facility to 15 MW.« less

With a little help from my kin: barn swallow nestlings modulate solicitation of parental care according to nestmates' need.

PubMed

Romano, Andrea; Caprioli, M; Boncoraglio, G; Saino, N; Rubolini, D

2012-09-01

In altricial species, offspring competing for access to limiting parental resources (e.g. food) are selected to achieve an optimal balance between the costs of scrambling for food, the benefits of being fed and the indirect costs of subtracting food to relatives. As the marginal benefits of acquiring additional food decrease with decreasing levels of need, satiated offspring should be prone to favour access to food by their needy kin, thus enhancing their own indirect fitness, while concomitantly reducing costs of harsh competition with hungry broodmates. We tested this prediction in feeding trials of barn swallow (Hirundo rustica) nestlings by comparing begging behaviour and food intake of two similar-sized nestmates, one of which was food-deprived (FD). Non-food-deprived (NFD) offspring modulated begging intensity depending on their nestmate's need: when competing with FD nestmates, NFD nestlings reduced both the intensity and frequency of begging displays compared to themselves in the control trial before food deprivation. Hence, NFD nestlings reduced their competitiveness to the advantage of FD nestmates, which obtained more feedings and showed a threefold larger increase in body mass. Moderation of individual selfishness can therefore be adaptive in the presence of a needier kin, because the indirect fitness benefits of promoting its condition can outweigh the costs of forgoing being fed, and because it limits the cost of begging escalation against a vigorous competitor. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Indirect nontarget effects of host-specific biological control agents: Implications for biological control

Treesearch

Dean E. Pearson; Ragan M. Callaway

2005-01-01

Classical biological control of weeds currently operates under the assumption that biological control agents are safe (i.e., low risk) if they do not directly attack nontarget species. However, recent studies indicate that even highly host-specific biological control agents can impact nontarget species through indirect effects. This finding has profound...

Direct versus Indirect and Individual versus Group Modes of Language Therapy for Children with Primary Language Impairment: Principal Outcomes from a Randomized Controlled Trial and Economic Evaluation

ERIC Educational Resources Information Center

Boyle, James M.; McCartney, Elspeth; O'Hare, Anne; Forbes, John

2009-01-01

Background: Many school-age children with language impairments are enrolled in mainstream schools and receive indirect language therapy, but there have been, to the authors' knowledge, no previous controlled studies comparing the outcomes and costs of direct and indirect intervention delivered by qualified therapists and therapy assistants, and…

Climate change: Cropping system changes and adaptations

USDA-ARS?s Scientific Manuscript database

Climate change impacts the life of every person; however, there is little comprehensive understanding of the direct and indirect effects of climate change on agriculture. Since our food, feed, fiber, and fruit is derived from agricultural systems, understanding the effects of changing temperature, p...

17 CFR 1.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... that directly or indirectly controls such individual, partnership, corporation or association; or (viii) A business affiliate that, directly or indirectly is controlled by or is under common control with... equivalent of fixed-price sales of the cash products and by-products of such commodity by the same person...

The direct and indirect cost burden of clinically significant and symptomatic uterine fibroids.

PubMed

Lee, David W; Ozminkowski, Ronald J; Carls, Ginger Smith; Wang, Shaohung; Gibson, Teresa B; Stewart, Elizabeth A

2007-05-01

To estimate direct medical costs and indirect (productivity related) for women age 25 to 54 who had clinically significant and symptomatic uterine fibroids (UF). We compared direct medical expenditures among 30,659 women who had clinically significant and symptomatic UF to expenditures among an equal number of matched controls who did not. We also compared indirect costs for a sub-sample of 910 employed women in each group. Regression analyses controlled for demographic and casemix factors. Mean 12-month direct medical costs for women with UF were $11,720 versus $3257 for controls, and mean 12-month indirect costs for women with UF were $11,752 versus $8083 for controls. Differences were statistically significant (P<0.0001). UF is a costly disorder and merits thought as interventions are considered to improve women's health and productivity.

A decade of occupational accidents due to direct or indirect electrical contact in the primary, secondary and tertiary sectors in Spain (2003-2012).

PubMed

Castillo-Rosa, Juan; Suárez-Cebador, Manuel; Rubio-Romero, Juan Carlos; Aguado, Jose Antonio

2017-03-01

Occupational accidents caused by electrical contact are a major concern worldwide due to their severe consequences. The study conducted is based on an analysis of the evolution of incidence rates and dependence between variables for 14,022 electrical accidents occurring in Spain between 2003 and 2012. The results show that electrical accidents as a whole are 3.6 times more likely to have severe consequences than the rest of the accidents in the country. This proportion is even nine times greater in the case of fatal accidents. They also confirm a significant relationship between the severity of this type of accidents and the economic sector in which they occur. On the other hand, there is a positive trend in the reduction of the incidence rate, especially in relation to direct contact, although unexpectedly the rate of accidents due to indirect contact is on the rise. Thus, preventing electrical occupational accidents requires efforts to guarantee adequate training adapted to the needs of workers in the various economic sectors. Furthermore, those responsible for safety should work to implement mechanisms to monitor and control compliance with efficient protective measures against electrical contact.

Selection and Neutral Mutations Drive Pervasive Mutability Losses in Long-Lived Anti-HIV B-Cell Lineages

PubMed Central

Vieira, Marcos C; Zinder, Daniel; Cobey, Sarah

2018-01-01

Abstract High-affinity antibodies arise within weeks of infection from the evolution of B-cell receptors under selection to improve antigen recognition. This rapid adaptation is enabled by the distribution of highly mutable “hotspot” motifs in B-cell receptor genes. High mutability in antigen-binding regions (complementarity determining regions [CDRs]) creates variation in binding affinity, whereas low mutability in structurally important regions (framework regions [FRs]) may reduce the frequency of destabilizing mutations. During the response, loss of mutational hotspots and changes in their distribution across CDRs and FRs are predicted to compromise the adaptability of B-cell receptors, yet the contributions of different mechanisms to gains and losses of hotspots remain unclear. We reconstructed changes in anti-HIV B-cell receptor sequences and show that mutability losses were ∼56% more frequent than gains in both CDRs and FRs, with the higher relative mutability of CDRs maintained throughout the response. At least 21% of the total mutability loss was caused by synonymous mutations. However, nonsynonymous substitutions caused most (79%) of the mutability loss in CDRs. Because CDRs also show strong positive selection, this result suggests that selection for mutations that increase binding affinity contributed to loss of mutability in antigen-binding regions. Although recurrent adaptation to evolving viruses could indirectly select for high mutation rates, we found no evidence of indirect selection to increase or retain hotspots. Our results suggest mutability losses are intrinsic to both the neutral and adaptive evolution of B-cell populations and might constrain their adaptation to rapidly evolving pathogens such as HIV and influenza. PMID:29688540

Caffeinated and Non-caffeinated Alcohol Use and Indirect Aggression: The Impact of Self-regulation

PubMed Central

Sheehan, Brynn E.; Linden-Carmichael, Ashley N.; Lau-Barraco, Cathy

2016-01-01

Research shows that heavier alcohol use is associated with physical aggression. Scant research has examined the way in which alcohol relates to other forms of aggression, such as indirect aggression (e.g., malicious humor, social exclusion). Given the possible negative consequences of indirect aggression and the limited evidence suggesting alcohol use can elicit indirectly aggressive responses, research is needed to further investigate the association between drinking behavior and indirect aggression. Additionally, specific alcoholic beverages, such as caffeinated alcoholic beverages (CABs; e.g., Red Bull and vodka), may potentiate aggression above the influence of typical use, thus warrant examination with regard to indirect aggression. One factor that may impact the strength of the alcohol-indirect aggression and CAB-indirect aggression relationships is one's level of self-regulation. Consequently, our study examined the relationships between (1) alcohol use and indirect aggression, (2) CAB use and indirect aggression, and (3) self-regulation as a moderator. Participants were 733 (67.6% female) undergraduate students who reported their CAB and alcohol use, self-regulation, and aggressive behaviors. Results revealed that heavier alcohol use was associated with more frequent indirect aggression after controlling for dispositional aggression. Heavier CAB use was related to more frequent indirect aggression after accounting for typical use and dispositional aggression. Self-regulation moderated these associations such that for those with lower self-regulation, greater alcohol and CAB consumption was associated with greater indirect aggression. Our findings suggest that heavier alcohol and CAB consumption may be risk factors for engaging in indirect aggression and this risk is impacted by one's regulatory control. PMID:26905765

On the Relationship between the Indirectly Measured Attitude Towards Beer and Beer Consumption: The Role of Attitude Accessibility

PubMed Central

Descheemaeker, Mathilde; Spruyt, Adriaan; Hermans, Dirk

2014-01-01

Although some studies have demonstrated that the indirectly measured attitude towards alcohol is related to alcohol use, this relationship has not always been confirmed. In the current study, we attempted to shed light on this issue by investigating whether the predictive validity of an indirect attitude measure is dependent upon attitude accessibility. In a sample of 88 students, the picture-picture naming task, an adaptation of the affective priming paradigm, was used to measure the automatically activated attitude towards beer. Attitude accessibility was measured using a speeded evaluative categorization task. Behavioral measures were the amount of beer poured and drunk during a bogus taste test and the choice between a bottle of beer or water at the end of the experiment. In line with our hypothesis, the indirectly measured attitude towards beer predicted behavior during the taste test only when it was highly accessible. In contrast, this attitude was related to choice behavior irrespective of attitude accessibility. This study confirms that indirect attitude measures can be valuable predictors of alcohol-related behavior, but that it is sometimes necessary to take attitude accessibility into account. PMID:24777156

On the relationship between the indirectly measured attitude towards beer and beer consumption: the role of attitude accessibility.

PubMed

Descheemaeker, Mathilde; Spruyt, Adriaan; Hermans, Dirk

2014-01-01

Although some studies have demonstrated that the indirectly measured attitude towards alcohol is related to alcohol use, this relationship has not always been confirmed. In the current study, we attempted to shed light on this issue by investigating whether the predictive validity of an indirect attitude measure is dependent upon attitude accessibility. In a sample of 88 students, the picture-picture naming task, an adaptation of the affective priming paradigm, was used to measure the automatically activated attitude towards beer. Attitude accessibility was measured using a speeded evaluative categorization task. Behavioral measures were the amount of beer poured and drunk during a bogus taste test and the choice between a bottle of beer or water at the end of the experiment. In line with our hypothesis, the indirectly measured attitude towards beer predicted behavior during the taste test only when it was highly accessible. In contrast, this attitude was related to choice behavior irrespective of attitude accessibility. This study confirms that indirect attitude measures can be valuable predictors of alcohol-related behavior, but that it is sometimes necessary to take attitude accessibility into account.

Influences of mastery, spousal support, and adaptive coping on sexual drive and satisfaction among chinese gynecologic cancer survivors.

PubMed

Tang, Catherine So-Kum; Lai, Beatrice P Y; Chung, Tony K H

2010-10-01

This study investigated sexual drive and satisfaction of Chinese gynecologic cancer survivors. It also examined the extent to which personal mastery, adaptive coping, and perceived spousal support would exert direct and/or indirect influences on sexual outcomes. The cancer survivor group included 134 Chinese women who had received treatment for gynecologic cancer, while the healthy control group included 105 Chinese women who did not have a known history or current diagnosis of cancer. Compared to healthy women, cancer survivors reported lower levels of sexual drive and sexual satisfaction. Among sexually active participants, cancer survivors relative to healthy women engaged in less masturbation, less kissing and caressing, and less sexual fantasy in the past month. Hierarchical multiple regression analyses showed that mastery and spousal support, but not adaptive coping, had a direct influence on sexual outcomes in cancer survivors. Contrary to moderation hypotheses, the three psychological factors did not interact with each other to influence sexual drive and satisfaction. Mediation analyses showed that spousal support fully mediated the influence of mastery on sexual satisfaction. Routine assessment of sexual functioning prior to and following treatment of gynecologic cancer is suggested. Sexual rehabilitation should also aim to enhance personal mastery and spousal support.

Measuring acuity of the approximate number system reliably and validly: the evaluation of an adaptive test procedure

PubMed Central

Lindskog, Marcus; Winman, Anders; Juslin, Peter; Poom, Leo

2013-01-01

Two studies investigated the reliability and predictive validity of commonly used measures and models of Approximate Number System acuity (ANS). Study 1 investigated reliability by both an empirical approach and a simulation of maximum obtainable reliability under ideal conditions. Results showed that common measures of the Weber fraction (w) are reliable only when using a substantial number of trials, even under ideal conditions. Study 2 compared different purported measures of ANS acuity as for convergent and predictive validity in a within-subjects design and evaluated an adaptive test using the ZEST algorithm. Results showed that the adaptive measure can reduce the number of trials needed to reach acceptable reliability. Only direct tests with non-symbolic numerosity discriminations of stimuli presented simultaneously were related to arithmetic fluency. This correlation remained when controlling for general cognitive ability and perceptual speed. Further, the purported indirect measure of ANS acuity in terms of the Numeric Distance Effect (NDE) was not reliable and showed no sign of predictive validity. The non-symbolic NDE for reaction time was significantly related to direct w estimates in a direction contrary to the expected. Easier stimuli were found to be more reliable, but only harder (7:8 ratio) stimuli contributed to predictive validity. PMID:23964256

The Indirect Path From Mindful Parenting to Emotional Problems in Adolescents: The Role of Maternal Warmth and Adolescents’ Mindfulness

PubMed Central

Wang, Yuyin; Liang, Yiying; Fan, Linlin; Lin, Kexiu; Xie, Xiaolin; Pan, Junhao; Zhou, Hui

2018-01-01

Mindfulness has been demonstrated to have positive effects on children’s emotional functioning, and adaptive parenting practices are associated with fewer emotional problems. However, the association between mindful parenting and adolescent emotional problems has not been studied much. In the current study, the indirect path from mindful parenting to adolescent emotional problems was examined, with maternal warmth and adolescent dispositional mindfulness as potential mediators. A sample of 168 mother–child dyads participated in this study. A serial indirect effects model showed mother’s mindful parenting could decrease adolescent emotional problems through adolescent’s perceived maternal warmth and their dispositional mindfulness. Findings of this study imply that intervention in mindful parenting may have benefits for adolescents’ emotional problems through enhancing maternal warmth and children’s trait mindfulness. PMID:29706925

Mitochondrial chaperones may be targets for anti-cancer drugs

Cancer.gov

Scientists at NCI have found that a mitochondrial chaperone protein, TRAP1, may act indirectly as a tumor suppressor as well as a novel target for developing anti-cancer drugs. Chaperone proteins, such as TRAP1, help other proteins adapt to stress, but sc

Reversible large–scale modification of cortical networks during neuroprosthetic control

PubMed Central

Ganguly, Karunesh; Wallis, Jonathan D.

2012-01-01

Brain-Machine Interfaces (BMI) provide a framework to study cortical dynamics and the neural correlates of learning. Neuroprosthetic control has been associated with tuning changes in specific neurons directly projecting to the BMI (hereafter ‘direct neurons’). However, little is known about the larger network dynamics. By monitoring ensembles of neurons that were either causally linked to BMI control or indirectly involved, here we show that proficient neuroprosthetic control is associated with large-scale modifications to the cortical network in macaque monkeys. Specifically, there were changes in the preferred direction of both direct and indirect neurons. Interestingly, with learning, there was a relative decrease in the net modulation of indirect neural activity in comparison to the direct activity. These widespread differential changes in the direct and indirect population activity were remarkably stable from one day to the next and readily coexisted with the long-standing cortical network for upper limb control. Thus, the process of learning BMI control is associated with differential modification of neural populations based on their specific relation to movement control. PMID:21499255

Reversible large-scale modification of cortical networks during neuroprosthetic control.

PubMed

Ganguly, Karunesh; Dimitrov, Dragan F; Wallis, Jonathan D; Carmena, Jose M

2011-05-01

Brain-machine interfaces (BMIs) provide a framework for studying cortical dynamics and the neural correlates of learning. Neuroprosthetic control has been associated with tuning changes in specific neurons directly projecting to the BMI (hereafter referred to as direct neurons). However, little is known about the larger network dynamics. By monitoring ensembles of neurons that were either causally linked to BMI control or indirectly involved, we found that proficient neuroprosthetic control is associated with large-scale modifications to the cortical network in macaque monkeys. Specifically, there were changes in the preferred direction of both direct and indirect neurons. Notably, with learning, there was a relative decrease in the net modulation of indirect neural activity in comparison with direct activity. These widespread differential changes in the direct and indirect population activity were markedly stable from one day to the next and readily coexisted with the long-standing cortical network for upper limb control. Thus, the process of learning BMI control is associated with differential modification of neural populations based on their specific relation to movement control.

Neural network-based motion control of an underactuated wheeled inverted pendulum model.

PubMed

Yang, Chenguang; Li, Zhijun; Cui, Rongxin; Xu, Bugong

2014-11-01

In this paper, automatic motion control is investigated for one of wheeled inverted pendulum (WIP) models, which have been widely applied for modeling of a large range of two wheeled modern vehicles. First, the underactuated WIP model is decomposed into a fully actuated second order subsystem Σa consisting of planar movement of vehicle forward and yaw angular motions, and a nonactuated first order subsystem Σb of pendulum motion. Due to the unknown dynamics of subsystem Σa and the universal approximation ability of neural network (NN), an adaptive NN scheme has been employed for motion control of subsystem Σa . The model reference approach has been used whereas the reference model is optimized by the finite time linear quadratic regulation technique. The pendulum motion in the passive subsystem Σb is indirectly controlled using the dynamic coupling with planar forward motion of subsystem Σa , such that satisfactory tracking of a set pendulum tilt angle can be guaranteed. Rigours theoretic analysis has been established, and simulation studies have been performed to demonstrate the developed method.

Direct and indirect measures of Level-2 perspective-taking in children and adults.

PubMed

Surtees, Andrew D R; Butterfill, Stephen A; Apperly, Ian A

2012-03-01

Studies with infants show divergence between performance on theory of mind tasks depending on whether direct or indirect measures are used. It has been suggested that direct measures assess a flexible but cognitively demanding ability to reason about the minds of others, whereas indirect measures assess distinct processes which afford more efficient but less flexible theory of mind abilities (Apperly & Butterfill, 2009). This leads to the prediction that performance on indirect measures should be subject to signature limits. The current study tested whether the Level-1/Level-2 distinction might constitute one such limit. The study adapted a task that has shown evidence of Level-1 perspective-taking on both direct and indirect measures (Samson, Apperly, Braithwaite, Andrews, & Bodley-Scott, 2010). The aim was to test Level-2 perspective-taking in a sample of 6- to 11-year-olds (N = 80) and adults (N = 20). Participants were able to make Level-2 judgements on the direct measure. In contrast with the findings from Level-1 perspective-taking, there was no evidence of automatic processing of Level-2 perspectives on the indirect measure. This finding is consistent with the view that theory of mind abilities assessed by indirect measures are subject to signature limits. The Level-1/Level-2 distinction, suitably refined, marks one way in which efficient but inflexible theory of mind abilities are limited. © 2011 The British Psychological Society.

Estimation of indirect effect when the mediator is a censored variable.

PubMed

Wang, Jian; Shete, Sanjay

2017-01-01

A mediation model explores the direct and indirect effects of an initial variable ( X) on an outcome variable ( Y) by including a mediator ( M). In many realistic scenarios, investigators observe censored data instead of the complete data. Current research in mediation analysis for censored data focuses mainly on censored outcomes, but not censored mediators. In this study, we proposed a strategy based on the accelerated failure time model and a multiple imputation approach. We adapted a measure of the indirect effect for the mediation model with a censored mediator, which can assess the indirect effect at both the group and individual levels. Based on simulation, we established the bias in the estimations of different paths (i.e. the effects of X on M [ a], of M on Y [ b] and of X on Y given mediator M [ c']) and indirect effects when analyzing the data using the existing approaches, including a naïve approach implemented in software such as Mplus, complete-case analysis, and the Tobit mediation model. We conducted simulation studies to investigate the performance of the proposed strategy compared to that of the existing approaches. The proposed strategy accurately estimates the coefficients of different paths, indirect effects and percentages of the total effects mediated. We applied these mediation approaches to the study of SNPs, age at menopause and fasting glucose levels. Our results indicate that there is no indirect effect of association between SNPs and fasting glucose level that is mediated through the age at menopause.

Direct versus indirect and individual versus group modes of language therapy for children with primary language impairment: principal outcomes from a randomized controlled trial and economic evaluation.

PubMed

Boyle, James M; McCartney, Elspeth; O'Hare, Anne; Forbes, John

2009-01-01

Many school-age children with language impairments are enrolled in mainstream schools and receive indirect language therapy, but there have been, to the authors' knowledge, no previous controlled studies comparing the outcomes and costs of direct and indirect intervention delivered by qualified therapists and therapy assistants, and each delivery mode offered to children individually or in groups. To investigate the relative effectiveness of indirect and direct intervention therapy modes delivered individually or in groups for children with primary language impairment. A multi-centre randomized controlled trial investigated 161 children with primary language impairment aged 6-11 years randomized to a usual-therapy control group or to direct individual, indirect individual, direct group or indirect group therapy modes. Intervention was delivered three times a week for 30-40-min sessions in mainstream schools over 15 weeks. Language performance was assessed at baseline, post-therapy and at 12 months. Cost analysis was based on salary and travel costs for intervention modes and usual therapy. Compared with controls, children receiving project therapy made short-term improvements in expressive (p = 0.031), but not receptive, language immediately following intervention. Children with specific expressive language delay were more likely to show improvement than those with mixed receptive-expressive difficulties. The four project therapy modes did not differ on primary language outcomes (all p-values>0.392) and there were no further improvements evident at follow-up. Indirect group therapy was the least costly mode, with direct individual therapy the most costly. Intervention in this age group can be effective for expressive language and can be delivered equally effectively though speech and language therapy assistants and to children in groups.

Lineage dynamics and mutation-selection balance in non-adapting asexual populations

NASA Astrophysics Data System (ADS)

Pénisson, Sophie; Sniegowski, Paul D.; Colato, Alexandre; Gerrish, Philip J.

2013-02-01

In classical population genetics, mutation-selection balance refers to the equilibrium frequency of a deleterious allele established and maintained under two opposing forces: recurrent mutation, which tends to increase the frequency of the allele; and selection, which tends to decrease its frequency. In a haploid population, if μ denotes the per capita rate of production of the deleterious allele by mutation and s denotes the selective disadvantage of carrying the allele, then the classical mutation-selection balance frequency of the allele is approximated by μ/s. This calculation assumes that lineages carrying the mutant allele in question—the ‘focal allele’—do not accumulate deleterious mutations linked to the focal allele. In principle, indirect selection against the focal allele caused by such additional mutations can decrease the frequency of the focal allele below the classical mutation-selection balance. This effect of indirect selection will be strongest in an asexual population, in which the entire genome is in linkage. Here, we use an approach based on a multitype branching process to investigate this effect, analyzing lineage dynamics under mutation, direct selection, and indirect selection in a non-adapting asexual population. We find that the equilibrium balance between recurrent mutation to the focal allele and the forces of direct and indirect selection against the focal allele is closely approximated by γμ/(s + U) (s = 0 if the focal allele is neutral), where γ ≈ eθθ-(ω+θ)(ω + θ)(Γ(ω + θ) - Γ(ω + θ,θ)), \\theta =U/\\tilde {s}, and \\omega =s/\\tilde {s}; U denotes the genomic deleterious mutation rate and \\tilde {s} denotes the geometric mean selective disadvantage of deleterious mutations elsewhere on the genome. This mutation-selection balance for asexual populations can remain surprisingly invariant over wide ranges of the mutation rate.

Interpreting indirect treatment comparisons and network meta-analysis for health-care decision making: report of the ISPOR Task Force on Indirect Treatment Comparisons Good Research Practices: part 1.

PubMed

Jansen, Jeroen P; Fleurence, Rachael; Devine, Beth; Itzler, Robbin; Barrett, Annabel; Hawkins, Neil; Lee, Karen; Boersma, Cornelis; Annemans, Lieven; Cappelleri, Joseph C

2011-06-01

Evidence-based health-care decision making requires comparisons of all relevant competing interventions. In the absence of randomized, controlled trials involving a direct comparison of all treatments of interest, indirect treatment comparisons and network meta-analysis provide useful evidence for judiciously selecting the best choice(s) of treatment. Mixed treatment comparisons, a special case of network meta-analysis, combine direct and indirect evidence for particular pairwise comparisons, thereby synthesizing a greater share of the available evidence than a traditional meta-analysis. This report from the ISPOR Indirect Treatment Comparisons Good Research Practices Task Force provides guidance on the interpretation of indirect treatment comparisons and network meta-analysis to assist policymakers and health-care professionals in using its findings for decision making. We start with an overview of how networks of randomized, controlled trials allow multiple treatment comparisons of competing interventions. Next, an introduction to the synthesis of the available evidence with a focus on terminology, assumptions, validity, and statistical methods is provided, followed by advice on critically reviewing and interpreting an indirect treatment comparison or network meta-analysis to inform decision making. We finish with a discussion of what to do if there are no direct or indirect treatment comparisons of randomized, controlled trials possible and a health-care decision still needs to be made. Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

The recognition signal hypothesis for the adaptive evolution of religion : a phylogenetic test with Christian denominations.

PubMed

Matthews, Luke J

2012-06-01

Recent research on the evolution of religion has focused on whether religion is an unselected by-product of evolutionary processes or if it is instead an adaptation by natural selection. Adaptive hypotheses for religion include direct fitness benefits from improved health and indirect fitness benefits mediated by costly signals and/or cultural group selection. Herein, I propose that religious denominations achieve indirect fitness gains for members through the use of ecologically arbitrary beliefs, rituals, and moral rules that function as recognition markers of cultural inheritance analogous to kin and species recognition of genetic inheritance in biology. This recognition signal hypotheses could act in concert with either costly signaling or cultural group selection to produce evolutionarily altruistic behaviors within denominations. Using a cultural phylogenetic analysis, I show that a large set of religious behaviors among extant Christian denominations supports the prediction of the recognition signal hypothesis that characters change more frequently near historical schisms. By incorporating demographic data into the model, I show that more-distinctive denominations, as measured through dissimilar characteristics, appear to be protected from intrusion by nonmembers in mixed-denomination households, and that they may be experiencing greater biological growth of their populations even in the present day.

Functional Evidence for Memory Stabilization in Sensorimotor Adaptation: A 24-h Resting-State fMRI Study.

PubMed

Della-Maggiore, Valeria; Villalta, Jorge I; Kovacevic, Natasa; McIntosh, Anthony Randal

2017-03-01

Adaptation learning is crucial to maintain precise motor control in face of environmental perturbations. Although much progress has been made in understanding the psychophysics and neurophysiology of sensorimotor adaptation (SA), the time course of memory consolidation remains elusive. The lack of a reproducible gradient of memory resistance using protocols of retrograde interference has even led to the proposal that memories produced through SA do not consolidate. Here, we pursued an alternative approach using resting-state fMRI to track changes in functional connectivity (FC) induced by learning. Given that consolidation leads to long-term memory, we hypothesized that a change in FC that predicted long-term memory but not short-term memory would provide indirect evidence for memory stabilization. Six scans were acquired before, 15 min, 1, 3, 5.5, and 24 h after training on a center-out task under veridical or distorted visual feedback. The experimental group showed an increment in FC of a network including motor, premotor, posterior parietal cortex, cerebellum, and putamen that peaked at 5.5 h. Crucially, the strengthening of this network correlated positively with long-term retention but negatively with short-term retention. Our work provides evidence, suggesting that adaptation memories stabilize within a 6-h window, and points to different mechanisms subserving short- and long-term memory. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Evolution of speech-specific cognitive adaptations.

PubMed

de Boer, Bart

2015-01-01

This paper argues that an evolutionary perspective is natural when investigating cognitive adaptations related to language. This is because there appears to be correspondence between traits that linguists consider interesting and traits that have undergone selective pressure related to language. The paper briefly reviews theoretical results that shed light on what kind of adaptations we can expect to have evolved and then reviews concrete work related to the evolution of adaptations for combinatorial speech. It turns out that there is as yet no strong direct evidence for cognitive traits that have undergone selection related to speech, but there is indirect evidence that indicates selection. However, the traits that may have undergone selection are expected to be continuously variable ones, rather than the discrete ones that linguists have focused on traditionally.

Local adaptation to temperature conserves top-down control in a grassland food web.

PubMed

Barton, Brandon T

2011-10-22

A fundamental limitation in many climate change experiments is that tests represent relatively short-term 'shock' experiments and so do not incorporate the phenotypic plasticity or evolutionary change that may occur during the gradual process of climate change. However, capturing this aspect of climate change effects in an experimental design is a difficult challenge that few studies have accomplished. I examined the effect of temperature and predator climate history in food webs composed of herbaceous plants, generalist grasshopper herbivores and spider predators across a natural 4.8°C temperature gradient spanning 500 km in northeastern USA. In these grasslands, the effects of rising temperatures on the plant community are indirect and arise via altered predator-herbivore interactions. Experimental warming had no direct effect on grasshoppers, but reduced predation risk effects by causing spiders from all study sites to seek thermal refuge lower in the plant canopy. However, spider thermal tolerance corresponded to spider origin such that spiders from warmer study sites tolerated higher temperatures than spiders from cooler study sites. As a consequence, the magnitude of the indirect effect of spiders on plants did not differ along the temperature gradient, although a reciprocal transplant experiment revealed significantly different effects of spider origin on the magnitude of top-down control. These results suggest that variation in predator response to warming may maintain species interactions and associated food web processes when faced with long term, chronic climate warming.

Indirect and direct perceived behavioral control and the role of intention in the context of birth control behavior.

PubMed

Hanson, Jessica D; Nothwehr, Faryle; Yang, Jingzhen Ginger; Romitti, Paul

2015-07-01

Unintended pregnancies can have negative consequences for both mother and child. The focus of this study was to utilize perceived behavioral control measures (PBC; part of the theory of planned behavior) to identify relevant behavioral determinants of birth control use. This study also tested associations between direct and indirect PBC measures and intention of birth control use and between intention and birth control use. The methods included a randomly selected sample of patients at a health care system in the Upper Midwest who were sent a self-administered survey, with 190 non-pregnant women returning completed surveys. Participants indicated a high level of control over using birth control, and a significant positive correlation was observed between direct and indirect PBC measures. Participants also reported high intentions to use birth control, and a significant positive correlation was observed between intention and PBC. Additionally, both PBC measures and intention were independently and significantly associated with behavior, and PBC remained significantly associated with behavior when intention was added into the model. In conclusion, compared to the previous literature, this study is unique in that it examines indirect PBC measures and also the important role that PBC plays with actual birth control behavior.

Indirect and Direct Perceived Behavioral Control and the Role of Intention in the Context of Birth Control Behavior

PubMed Central

Nothwehr, Faryle; Yang, Jingzhen Ginger; Romitti, Paul

2018-01-01

Unintended pregnancies can have negative consequences for both mother and child. The focus of this study was to utilize perceived behavioral control measures (PBC; part of the theory of planned behavior) to identify relevant behavioral determinants of birth control use. This study also tested associations between direct and indirect PBC measures and intention of birth control use and between intention and birth control use. The methods included a randomly selected sample of patients at a health care system in the Upper Midwest who were sent a self-administered survey, with 190 non-pregnant women returning completed surveys. Participants indicated a high level of control over using birth control, and a significant positive correlation was observed between direct and indirect PBC measures. Participants also reported high intentions to use birth control, and a significant positive correlation was observed between intention and PBC. Additionally, both PBC measures and intention were independently and significantly associated with behavior, and PBC remained significantly associated with behavior when intention was added into the model. In conclusion, compared to the previous literature, this study is unique in that it examines indirect PBC measures and also the important role that PBC plays with actual birth control behavior. PMID:25421330

Method for evaluating multiple mediators: mediating effects of smoking and COPD on the association between the CHRNA5-A3 variant and lung cancer risk.

PubMed

Wang, Jian; Spitz, Margaret R; Amos, Christopher I; Wu, Xifeng; Wetter, David W; Cinciripini, Paul M; Shete, Sanjay

2012-01-01

A mediation model explores the direct and indirect effects between an independent variable and a dependent variable by including other variables (or mediators). Mediation analysis has recently been used to dissect the direct and indirect effects of genetic variants on complex diseases using case-control studies. However, bias could arise in the estimations of the genetic variant-mediator association because the presence or absence of the mediator in the study samples is not sampled following the principles of case-control study design. In this case, the mediation analysis using data from case-control studies might lead to biased estimates of coefficients and indirect effects. In this article, we investigated a multiple-mediation model involving a three-path mediating effect through two mediators using case-control study data. We propose an approach to correct bias in coefficients and provide accurate estimates of the specific indirect effects. Our approach can also be used when the original case-control study is frequency matched on one of the mediators. We employed bootstrapping to assess the significance of indirect effects. We conducted simulation studies to investigate the performance of the proposed approach, and showed that it provides more accurate estimates of the indirect effects as well as the percent mediated than standard regressions. We then applied this approach to study the mediating effects of both smoking and chronic obstructive pulmonary disease (COPD) on the association between the CHRNA5-A3 gene locus and lung cancer risk using data from a lung cancer case-control study. The results showed that the genetic variant influences lung cancer risk indirectly through all three different pathways. The percent of genetic association mediated was 18.3% through smoking alone, 30.2% through COPD alone, and 20.6% through the path including both smoking and COPD, and the total genetic variant-lung cancer association explained by the two mediators was 69.1%.

Sequential Monte Carlo Instant Radiosity.

PubMed

Hedman, Peter; Karras, Tero; Lehtinen, Jaakko

2017-05-01

Instant Radiosity and its derivatives are interactive methods for efficiently estimating global (indirect) illumination. They represent the last indirect bounce of illumination before the camera as the composite radiance field emitted by a set of virtual point light sources (VPLs). In complex scenes, current algorithms suffer from a difficult combination of two issues: it remains a challenge to distribute VPLs in a manner that simultaneously gives a high-quality indirect illumination solution for each frame, and to do so in a temporally coherent manner. We address both issues by building, and maintaining over time, an adaptive and temporally coherent distribution of VPLs in locations where they bring indirect light to the image. We introduce a novel heuristic sampling method that strives to only move as few of the VPLs between frames as possible. The result is, to the best of our knowledge, the first interactive global illumination algorithm that works in complex, highly-occluded scenes, suffers little from temporal flickering, supports moving cameras and light sources, and is output-sensitive in the sense that it places VPLs in locations that matter most to the final result.

Genomic estimation of complex traits reveals ancient maize adaptation to temperate North America.

PubMed

Swarts, Kelly; Gutaker, Rafal M; Benz, Bruce; Blake, Michael; Bukowski, Robert; Holland, James; Kruse-Peeples, Melissa; Lepak, Nicholas; Prim, Lynda; Romay, M Cinta; Ross-Ibarra, Jeffrey; Sanchez-Gonzalez, Jose de Jesus; Schmidt, Chris; Schuenemann, Verena J; Krause, Johannes; Matson, R G; Weigel, Detlef; Buckler, Edward S; Burbano, Hernán A

2017-08-04

By 4000 years ago, people had introduced maize to the southwestern United States; full agriculture was established quickly in the lowland deserts but delayed in the temperate highlands for 2000 years. We test if the earliest upland maize was adapted for early flowering, a characteristic of modern temperate maize. We sequenced fifteen 1900-year-old maize cobs from Turkey Pen Shelter in the temperate Southwest. Indirectly validated genomic models predicted that Turkey Pen maize was marginally adapted with respect to flowering, as well as short, tillering, and segregating for yellow kernel color. Temperate adaptation drove modern population differentiation and was selected in situ from ancient standing variation. Validated prediction of polygenic traits improves our understanding of ancient phenotypes and the dynamics of environmental adaptation. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Convergence of terrestrial plant production across global climate gradients.

PubMed

Michaletz, Sean T; Cheng, Dongliang; Kerkhoff, Andrew J; Enquist, Brian J

2014-08-07

Variation in terrestrial net primary production (NPP) with climate is thought to originate from a direct influence of temperature and precipitation on plant metabolism. However, variation in NPP may also result from an indirect influence of climate by means of plant age, stand biomass, growing season length and local adaptation. To identify the relative importance of direct and indirect climate effects, we extend metabolic scaling theory to link hypothesized climate influences with NPP, and assess hypothesized relationships using a global compilation of ecosystem woody plant biomass and production data. Notably, age and biomass explained most of the variation in production whereas temperature and precipitation explained almost none, suggesting that climate indirectly (not directly) influences production. Furthermore, our theory shows that variation in NPP is characterized by a common scaling relationship, suggesting that global change models can incorporate the mechanisms governing this relationship to improve predictions of future ecosystem function.

Utilizing optical coherence tomography for CAD/CAM of indirect dental restorations

NASA Astrophysics Data System (ADS)

Chityala, Ravishankar; Vidal, Carola; Jones, Robert

Optical Coherence Tomography (OCT) has seen broad application in dentistry including early carious lesion detection and imaging defects in resin composite restorations. This study investigates expanding the clinical usefulness by investigating methods to use OCT for obtaining three-dimensional (3D) digital impressions, which can be integrated to CAD/CAM manufacturing of indirect restorations. 3D surface topography `before' and `after' a cavity preparation was acquired by an intraoral cross polarization swept source OCT (CP-OCT) system with a Micro-Electro-Mechanical System (MEMS) scanning mirror. Image registration and segmentation methods were used to digitally construct a replacement restoration that modeled the original surface morphology of a hydroxyapatite sample. After high resolution additive manufacturing (e.g. polymer 3D printing) of the replacement restoration, micro-CT imaging was performed to examine the marginal adaptation. This study establishes the protocol for further investigation of integrating OCT with CAD/CAM of indirect dental restorations.

Preparing for Children with Disabilities in Early Childhood Classrooms.

ERIC Educational Resources Information Center

Favazza, Paddy C.

1998-01-01

Offers suggestions to kindergarten teachers for creating a more accepting environment in their classrooms for children with disabilities. Three key influences in attitude formation are discussed--indirect experiences, direct experiences, and the child's primary social group--and ideas for examining these influences and adapting them are suggested.…

Indirect current control with separate IZ drop compensation for voltage source converters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kanetkar, V.R.; Dawande, M.S.; Dubey, G.K.

1995-12-31

Indirect Current Control (ICC) of boost type Voltage Source Converters (VSCs) using separate compensation of line IZ voltage drop is presented. A separate bi-directional VSC is used to produce the compensation voltage. This simplifies the ICC regulator scheme as the power flow is controlled through single modulation index. Experimental verification is provided for bi-directional control of the power flow.

Backbone and stereospecific (13)C methyl Ile (δ1), Leu and Val side-chain chemical shift assignments of Crc.

PubMed

Sharma, Rakhi; Sahu, Bhubanananda; Ray, Malay K; Deshmukh, Mandar V

2015-04-01

Carbon catabolite repression (CCR) allows bacteria to selectively assimilate a preferred compound among a mixture of several potential carbon sources, thus boosting growth and economizing the cost of adaptability to variable nutrients in the environment. The RNA-binding catabolite repression control (Crc) protein acts as a global post-transcriptional regulator of CCR in Pseudomonas species. Crc triggers repression by inhibiting the expression of genes involved in transport and catabolism of non-preferred substrates, thus indirectly favoring assimilation of preferred one. We report here a nearly complete backbone and stereospecific (13)C methyl side-chain chemical shift assignments of Ile (δ1), Leu and Val of Crc (~ 31 kDa) from Pseudomonas syringae Lz4W.

Parenting processes and aggression: the role of self-control among Turkish adolescents.

PubMed

Özdemir, Yalçın; Vazsonyi, Alexander T; Çok, Figen

2013-02-01

The present study examined the direct and indirect relationships between parenting processes (parental closeness, parental monitoring, and parental peer approval), low self-control, and aggression. Participants were 546 adolescents aged 14-18 attending state high schools in Turkey. Participants completed a questionnaire that included measures of parenting processes, self-control, and aggression. Findings provided evidence of both direct and indirect effects of maternal and paternal parenting processes on aggression through low self-control. Specifically, results showed that maternal closeness, paternal peer approval and both maternal and paternal monitoring were positively and directly related to low self-control, and indirectly related to aggression through low self-control. Together, parenting processes and low self-control explained 21% of the variance in aggression. Implications for self-control theory and directions for future research are discussed. Copyright © 2012 The Foundation for Professionals in Services for Adolescents. All rights reserved.

Population-level compensation impedes biological control of an invasive forb and indirect release of a native grass

Treesearch

Yvette K. Ortega; Dean E. Pearson; Lauren P. Waller; Nancy J. Sturdevant; John L. Maron

2012-01-01

The intentional introduction of specialist insect herbivores for biological control of exotic weeds provides ideal but understudied systems for evaluating important ecological concepts related to top-down control, plant compensatory responses, indirect effects, and the influence of environmental context on these processes. Centaurea stoebe (spotted knapweed) is a...

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.

Genome-Wide Association Analysis of Adaptation Using Environmentally Predicted Traits.

PubMed

van Heerwaarden, Joost; van Zanten, Martijn; Kruijer, Willem

2015-10-01

Current methods for studying the genetic basis of adaptation evaluate genetic associations with ecologically relevant traits or single environmental variables, under the implicit assumption that natural selection imposes correlations between phenotypes, environments and genotypes. In practice, observed trait and environmental data are manifestations of unknown selective forces and are only indirectly associated with adaptive genetic variation. In theory, improved estimation of these forces could enable more powerful detection of loci under selection. Here we present an approach in which we approximate adaptive variation by modeling phenotypes as a function of the environment and using the predicted trait in multivariate and univariate genome-wide association analysis (GWAS). Based on computer simulations and published flowering time data from the model plant Arabidopsis thaliana, we find that environmentally predicted traits lead to higher recovery of functional loci in multivariate GWAS and are more strongly correlated to allele frequencies at adaptive loci than individual environmental variables. Our results provide an example of the use of environmental data to obtain independent and meaningful information on adaptive genetic variation.

Biologically Based Methods for Pest Management in Agriculture under Changing Climates: Challenges and Future Directions.

PubMed

Chidawanyika, Frank; Mudavanhu, Pride; Nyamukondiwa, Casper

2012-11-09

The current changes in global climatic regimes present a significant societal challenge, affecting in all likelihood insect physiology, biochemistry, biogeography and population dynamics. With the increasing resistance of many insect pest species to chemical insecticides and an increasing organic food market, pest control strategies are slowly shifting towards more sustainable, ecologically sound and economically viable options. Biologically based pest management strategies present such opportunities through predation or parasitism of pests and plant direct or indirect defense mechanisms that can all be important components of sustainable integrated pest management programs. Inevitably, the efficacy of biological control systems is highly dependent on natural enemy-prey interactions, which will likely be modified by changing climates. Therefore, knowledge of how insect pests and their natural enemies respond to climate variation is of fundamental importance in understanding biological insect pest management under global climate change. Here, we discuss biological control, its challenges under climate change scenarios and how increased global temperatures will require adaptive management strategies to cope with changing status of insects and their natural enemies.

78 FR 39407 - Self-Regulatory Organizations; New York Stock Exchange LLC; Notice of Filing of Proposed Rule...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-01

..., from having voting control over ICE Group shares entitling the holder thereof to cast more than 10% of..., the ICE Group Bylaws would provide that, so long as ICE Group directly or indirectly controls any U.S... directly or indirectly controls any U.S. Regulated Subsidiary, the books, records and premises of ICE Group...

78 FR 39369 - Self-Regulatory Organizations; NYSE MKT LLC; Notice of Filing of Proposed Rule Change Relating to...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-01

... person, either alone or together with its related persons, from having voting control over ICE Group... as ICE Group directly or indirectly controls any U.S. Regulated Subsidiary, the directors, officers... ICE Group Bylaws would provide that for so long as ICE Group directly or indirectly controls any U.S...

Harsh parenting and academic achievement in Chinese adolescents: Potential mediating roles of effortful control and classroom engagement.

PubMed

Wang, Mingzhong; Deng, Xueli; Du, Xiuxiu

2018-04-01

This study examined (a) the potential mediating roles of effortful control and classroom engagement in the association between harsh parenting and adolescent academic achievement, and (b) the potential moderating role of gender. Sixth through eighth graders in rural China (n=815, mean age=12.55years) reported on harsh parenting, effortful control, and classroom engagement. Parents also reported on each other's harsh parenting. Academic achievement was assessed by students' test scores and teacher-rated academic performance. Results of structural equation modeling revealed gender differences in patterns of association among the model variables. Harsh parenting was negatively and directly associated with academic achievement for both boys and girls. It was also negatively and indirectly associated with academic achievement via effortful control and classroom engagement sequentially, forming a common indirect "path" for boys and girls. The indirect negative effect of harsh parenting on boys' academic achievement was mainly realized through the mediator of effortful control, whereas this same indirect effect for girls was mainly realized through the mediator of classroom engagement. Jointly, effortful control and classroom engagement precipitates more indirect effects for boys than for girls in the association between harsh parenting and academic achievement. The discussion analyzes the potential "paths" from harsh parenting to adolescent academic achievement, as well as gender differences in these "paths." The current study has implications for teachers and parents eager to improve students' classroom engagement and academic achievement. Copyright © 2017. Published by Elsevier Ltd.

Monitoring and Controlling Engineering and Construction Management Cost Performance Within the Corps of Engineers

DTIC Science & Technology

1988-12-01

COST MANAGEMENT The CMIF approach addresses total costs but does not permit the analysis of indirect costs. We found that indirect costs vary...responsibility USACE/divisions Increasing CMIF Districts/divisions level of by fund type detail G&A, technical indirect, burden Districts by fund type

Beam rider for an Articulated Robot Manipulator (ARM) accurate positioning of long flexible manipulators

NASA Technical Reports Server (NTRS)

Malachowski, M. J.

1990-01-01

Laser beam positioning and beam rider modules were incorporated into the long hollow flexible segment of an articulated robot manipulator (ARM). Using a single laser beam, the system determined the position of the distal ARM endtip, with millimetric precision, in six degrees of freedom, at distances of up to 10 meters. Preliminary designs, using space rated technology for the critical systems, of a two segmented physical ARM, with a single and a dual degree of freedom articulation, were developed, prototyped, and tested. To control the positioning of the physical ARM, an indirect adaptive controller, which used the mismatch between the position of the laser beam under static and dynamic conditions, was devised. To predict the behavior of the system and test the concept, a computer simulation model was constructed. A hierarchical artificially intelligent real time ADA operating system program structure was created. The software was designed for implementation on a dedicated VME bus based Intel 80386 administered parallel processing multi-tasking computer system.

Corticothalamic Synaptic Noise as a Mechanism for Selective Attention in Thalamic Neurons.

PubMed

Béhuret, Sébastien; Deleuze, Charlotte; Bal, Thierry

2015-01-01

A reason why the thalamus is more than a passive gateway for sensory signals is that two-third of the synapses of thalamocortical neurons are directly or indirectly related to the activity of corticothalamic axons. While the responses of thalamocortical neurons evoked by sensory stimuli are well characterized, with ON- and OFF-center receptive field structures, the prevalence of synaptic noise resulting from neocortical feedback in intracellularly recorded thalamocortical neurons in vivo has attracted little attention. However, in vitro and modeling experiments point to its critical role for the integration of sensory signals. Here we combine our recent findings in a unified framework suggesting the hypothesis that corticothalamic synaptic activity is adapted to modulate the transfer efficiency of thalamocortical neurons during selective attention at three different levels: First, on ionic channels by interacting with intrinsic membrane properties, second at the neuron level by impacting on the input-output gain, and third even more effectively at the cell assembly level by boosting the information transfer of sensory features encoded in thalamic subnetworks. This top-down population control is achieved by tuning the correlations in subthreshold membrane potential fluctuations and is adapted to modulate the transfer of sensory features encoded by assemblies of thalamocortical relay neurons. We thus propose that cortically-controlled (de-)correlation of subthreshold noise is an efficient and swift dynamic mechanism for selective attention in the thalamus.

Corticothalamic Synaptic Noise as a Mechanism for Selective Attention in Thalamic Neurons

PubMed Central

Béhuret, Sébastien; Deleuze, Charlotte; Bal, Thierry

2015-01-01

A reason why the thalamus is more than a passive gateway for sensory signals is that two-third of the synapses of thalamocortical neurons are directly or indirectly related to the activity of corticothalamic axons. While the responses of thalamocortical neurons evoked by sensory stimuli are well characterized, with ON- and OFF-center receptive field structures, the prevalence of synaptic noise resulting from neocortical feedback in intracellularly recorded thalamocortical neurons in vivo has attracted little attention. However, in vitro and modeling experiments point to its critical role for the integration of sensory signals. Here we combine our recent findings in a unified framework suggesting the hypothesis that corticothalamic synaptic activity is adapted to modulate the transfer efficiency of thalamocortical neurons during selective attention at three different levels: First, on ionic channels by interacting with intrinsic membrane properties, second at the neuron level by impacting on the input-output gain, and third even more effectively at the cell assembly level by boosting the information transfer of sensory features encoded in thalamic subnetworks. This top-down population control is achieved by tuning the correlations in subthreshold membrane potential fluctuations and is adapted to modulate the transfer of sensory features encoded by assemblies of thalamocortical relay neurons. We thus propose that cortically-controlled (de-)correlation of subthreshold noise is an efficient and swift dynamic mechanism for selective attention in the thalamus. PMID:26733818

Gender differentiation in indirect self-destructiveness and suicide attempt methods (gender, indirect self-destructiveness, and suicide attempts).

PubMed

Tsirigotis, Konstantinos; Gruszczyński, Wojciech; Tsirigotis-Maniecka, Marta

2014-06-01

The objective of this study is to examine the gender (sex) differentiation of indirect self-destructiveness and its manifestations as well as its relationships with suicide attempt methods in females and males. The study was conducted among 147 persons (114 females, 33 males) who attempted suicide. The research instrument was the polish version of the Chronic Self-Destructiveness Scale including Transgression and Risk, Poor Health Maintenance, Personal and Social Neglects, Lack of Planfulness, and Helplessness and Passiveness in the face of problems. Differences testing and correlation analyses were applied. Females scored higher on poor health maintenance and males scored significantly higher on personal and social neglects, lack of planfulness, and helplessness. Noteworthy is that the intensity of indirect self-destructiveness in females reached the same magnitude as in males. A number of statistically significant correlations were found between indirect self-destructiveness, or its manifestations, and the methods of suicide attempt in the two groups. Among these categories, the highest contribution was of helplessness and passiveness (both of groups), poor health maintenance (males), and personal and social neglects (females). Results of this study can be useful in the therapeutic efforts and prevention of not only indirectly self-destructive behaviours but also possible suicide attempts. Both preventive and therapeutic activities can take into account the specificity of those phenomena resulting from one's sex/gender. It is important to adapt preventive and therapeutic measures to psychological (personal) features that arise from an individual's sex/gender.

Temperature and humidity control in indirect calorimeter chambers

USDA-ARS?s Scientific Manuscript database

A three-chamber, indirect calorimeter has been a part of the Environmental Laboratory at the U.S. Meat Animal Research Center (MARC) for over 25 yr. Corrosion of the animal chambers and unreliable temperature control forced either major repairs or complete replacement. There is a strong demand for...

Climate Change: Could It Help Develop "Adaptive Expertise"?

ERIC Educational Resources Information Center

Bell, Erica; Horton, Graeme; Blashki, Grant; Seidel, Bastian M.

2012-01-01

Preparing health practitioners to respond to the rising burden of disease from climate change is emerging as a priority in health workforce policy and planning. However, this issue is hardly represented in the medical education research. The rapidly evolving wide range of direct and indirect consequences of climate change will require health…

Climate Change: Life history adaptation by a global whitefly, Bemisia tabaci, with rising temperature and carbon dioxide

USDA-ARS?s Scientific Manuscript database

Introduction: Climate change can have direct and indirect impacts on living organisms. A rise in ambient temperature and elevated carbon dioxide (CO2) concentrations due to global warming may have assorted impacts on arthropods such as altered life cycles, altered reproductive patterns, and change...

Brief Report: Feasibility and Preliminary Efficacy of Individual Mindfulness Therapy for Adults with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Conner, Caitlin M.; White, Susan W.

2018-01-01

Intervention research on adults with autism spectrum disorder (ASD) is sparse. Many adults with ASD experience impaired emotion regulation (ER), which is thought to contribute to higher rates of psychiatric comorbidities among adults with ASD and indirect effects upon adaptive functioning, interpersonal relationships, and vocational status. The…

Positive Socialization Mechanisms in Secure and Insecure Parent-Child Dyads: Two Longitudinal Studies

ERIC Educational Resources Information Center

Kochanska, Grazyna; Woodard, Jarilyn; Kim, Sanghag; Koenig, Jamie L.; Yoon, Jeung Eun; Barry, Robin A.

2010-01-01

Background: Implications of early attachment have been extensively studied, but little is known about its long-term indirect sequelae, where early security organization moderates future parent-child relationships, serving as a catalyst for adaptive and maladaptive processes. Two longitudinal multi-trait multi-method studies examined whether early…

The Influence of Proactive Socialization Behaviors and Team Socialization on Individual Performance in the Team

ERIC Educational Resources Information Center

Pennaforte, Antoine

2016-01-01

On the basis of the role and the social exchange theories, this research investigated the direct and indirect antecedents of three dimensions of team performance (proficiency, adaptivity, proactivity) developed through cooperative education. The theoretical model examined how proactive socialization behaviors led to team socialization and team…

Socio-economic impacts of climate change on rural United States

Treesearch

Pankaj Lal; Janaki R.R. Alavalapati; Evan Mercer

2011-01-01

Directly or indirectly, positively or negatively, climate change will affect all sectors and regions of the United States. The impacts, however, will not be homogenous across regions, sectors, population groups or time. The literature specifically related to how climate change will affect rural communities, their resilience, and adaptive capacity in the United States (...

Eye regression in blind Astyanax cavefish may facilitate the evolution of an adaptive behavior and its sensory receptors.

PubMed

Borowsky, Richard

2013-07-11

The forces driving the evolutionary loss or simplification of traits such as vision and pigmentation in cave animals are still debated. Three alternative hypotheses are direct selection against the trait, genetic drift, and indirect selection due to antagonistic pleiotropy. Recent work establishes that Astyanax cavefish exhibit vibration attraction behavior (VAB), a presumed behavioral adaptation to finding food in the dark not exhibited by surface fish. Genetic analysis revealed two regions in the genome with quantitative trait loci (QTL) for both VAB and eye size. These observations were interpreted as genetic evidence that selection for VAB indirectly drove eye regression through antagonistic pleiotropy and, further, that this is a general mechanism to account for regressive evolution. These conclusions are unsupported by the data; the analysis fails to establish pleiotropy and ignores the numerous other QTL that map to, and potentially interact, in the same regions. It is likely that all three forces drive evolutionary change. We will be able to distinguish among them in individual cases only when we have identified the causative alleles and characterized their effects.

Multiple Levels of Family Factors and Oppositional Defiant Disorder Symptoms Among Chinese Children.

PubMed

Lin, Xiuyun; Li, Longfeng; Heath, Melissa A; Chi, Peilian; Xu, Shousen; Fang, Xiaoyi

2018-03-01

Family factors are closely associated with child developmental outcomes. This study examined the relationship of oppositional defiant disorder (ODD) symptoms and factors at whole family, dyadic, and individual levels in Chinese children. Participants, who were recruited from 14 primary schools in north, east, and south-west China, included 80 father-child dyads and 169 mother-child dyads. Children in the participating dyads were previously diagnosed with ODD. Results revealed that family cohesion/adaptability was indirectly associated with ODD symptoms via parent-child relationship and child emotion regulation. Parent-child relationship affected ODD symptoms directly and indirectly through child emotion regulation. In addition, the effects of family cohesion/adaptability on parent emotion regulation and child emotion regulation were mediated by the parent-child relationship. The tested model provides a comprehensive framework of how family factors at multiple levels are related to child ODD symptoms and highlights the importance of understanding child emotional and behavioral problems within the family context, more specifically within the multiple levels of family relationships. © 2016 Family Process Institute.

Pollinator Foraging Adaptation and Coexistence of Competing Plants.

PubMed

Revilla, Tomás A; Křivan, Vlastimil

2016-01-01

We use the optimal foraging theory to study coexistence between two plant species and a generalist pollinator. We compare conditions for plant coexistence for non-adaptive vs. adaptive pollinators that adjust their foraging strategy to maximize fitness. When pollinators have fixed preferences, we show that plant coexistence typically requires both weak competition between plants for resources (e.g., space or nutrients) and pollinator preferences that are not too biased in favour of either plant. We also show how plant coexistence is promoted by indirect facilitation via the pollinator. When pollinators are adaptive foragers, pollinator's diet maximizes pollinator's fitness measured as the per capita population growth rate. Simulations show that this has two conflicting consequences for plant coexistence. On the one hand, when competition between pollinators is weak, adaptation favours pollinator specialization on the more profitable plant which increases asymmetries in plant competition and makes their coexistence less likely. On the other hand, when competition between pollinators is strong, adaptation promotes generalism, which facilitates plant coexistence. In addition, adaptive foraging allows pollinators to survive sudden loss of the preferred plant host, thus preventing further collapse of the entire community.

Adaptive Evolution of Mitochondrial Energy Metabolism Genes Associated with Increased Energy Demand in Flying Insects

PubMed Central

Yang, Yunxia; Xu, Shixia; Xu, Junxiao; Guo, Yan; Yang, Guang

2014-01-01

Insects are unique among invertebrates for their ability to fly, which raises intriguing questions about how energy metabolism in insects evolved and changed along with flight. Although physiological studies indicated that energy consumption differs between flying and non-flying insects, the evolution of molecular energy metabolism mechanisms in insects remains largely unexplored. Considering that about 95% of adenosine triphosphate (ATP) is supplied by mitochondria via oxidative phosphorylation, we examined 13 mitochondrial protein-encoding genes to test whether adaptive evolution of energy metabolism-related genes occurred in insects. The analyses demonstrated that mitochondrial DNA protein-encoding genes are subject to positive selection from the last common ancestor of Pterygota, which evolved primitive flight ability. Positive selection was also found in insects with flight ability, whereas no significant sign of selection was found in flightless insects where the wings had degenerated. In addition, significant positive selection was also identified in the last common ancestor of Neoptera, which changed its flight mode from direct to indirect. Interestingly, detection of more positively selected genes in indirect flight rather than direct flight insects suggested a stronger selective pressure in insects having higher energy consumption. In conclusion, mitochondrial protein-encoding genes involved in energy metabolism were targets of adaptive evolution in response to increased energy demands that arose during the evolution of flight ability in insects. PMID:24918926

Adaptive evolution of mitochondrial energy metabolism genes associated with increased energy demand in flying insects.

PubMed

Yang, Yunxia; Xu, Shixia; Xu, Junxiao; Guo, Yan; Yang, Guang

2014-01-01

Insects are unique among invertebrates for their ability to fly, which raises intriguing questions about how energy metabolism in insects evolved and changed along with flight. Although physiological studies indicated that energy consumption differs between flying and non-flying insects, the evolution of molecular energy metabolism mechanisms in insects remains largely unexplored. Considering that about 95% of adenosine triphosphate (ATP) is supplied by mitochondria via oxidative phosphorylation, we examined 13 mitochondrial protein-encoding genes to test whether adaptive evolution of energy metabolism-related genes occurred in insects. The analyses demonstrated that mitochondrial DNA protein-encoding genes are subject to positive selection from the last common ancestor of Pterygota, which evolved primitive flight ability. Positive selection was also found in insects with flight ability, whereas no significant sign of selection was found in flightless insects where the wings had degenerated. In addition, significant positive selection was also identified in the last common ancestor of Neoptera, which changed its flight mode from direct to indirect. Interestingly, detection of more positively selected genes in indirect flight rather than direct flight insects suggested a stronger selective pressure in insects having higher energy consumption. In conclusion, mitochondrial protein-encoding genes involved in energy metabolism were targets of adaptive evolution in response to increased energy demands that arose during the evolution of flight ability in insects.

Cost Effectiveness of the Angiotensin Receptor Neprilysin Inhibitor Sacubitril/Valsartan for Patients with Chronic Heart Failure and Reduced Ejection Fraction in the Netherlands: A Country Adaptation Analysis Under the Former and Current Dutch Pharmacoeconomic Guidelines.

PubMed

Ramos, Isaac Corro; Versteegh, Matthijs M; de Boer, Rudolf A; Koenders, Jolanda M A; Linssen, Gerard C M; Meeder, Joan G; Rutten-van Mölken, Maureen P M H

2017-12-01

To describe the adaptation of a global health economic model to determine whether treatment with the angiotensin receptor neprilysin inhibitor LCZ696 is cost effective compared with the angiotensin-converting enzyme inhibitor enalapril in adult patients with chronic heart failure with reduced left ventricular ejection fraction in the Netherlands; and to explore the effect of performing the cost-effectiveness analyses according to the new pharmacoeconomic Dutch guidelines (updated during the submission process of LCZ696), which require a value-of-information analysis and the inclusion of indirect medical costs of life-years gained. We adapted a UK model to reflect the societal perspective in the Netherlands by including travel expenses, productivity loss, informal care costs, and indirect medical costs during the life-years gained and performed a preliminary value-of-information analysis. The incremental cost-effectiveness ratio obtained was €17,600 per quality-adjusted life-year (QALY) gained. This was robust to changes in most structural assumptions and across different subgroups of patients. Probability sensitivity analysis results showed that the probability that LCZ696 is cost-effective at a €50,000 per QALY threshold is 99.8%, with a population expected value of perfect information of €297,128. On including indirect medical costs of life-years gained, the incremental cost-effectiveness ratio was €26,491 per QALY gained, and LCZ696 was 99.46% cost effective at €50,000 per QALY, with a population expected value of perfect information of €2,849,647. LCZ696 is cost effective compared with enalapril under the former and current Dutch guidelines. However, the (monetary) consequences of making a wrong decision were considerably different in both scenarios. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

AMPK signaling in skeletal muscle during exercise: Role of reactive oxygen and nitrogen species.

PubMed

Morales-Alamo, David; Calbet, Jose A L

2016-09-01

Reactive oxygen and nitrogen species (RONS) are generated during exercise depending on intensity, duration and training status. A greater amount of RONS is released during repeated high-intensity sprint exercise and when the exercise is performed in hypoxia. By activating adenosine monophosphate-activated kinase (AMPK), RONS play a critical role in the regulation of muscle metabolism but also in the adaptive responses to exercise training. RONS may activate AMPK by direct an indirect mechanisms. Directly, RONS may activate or deactivate AMPK by modifying RONS-sensitive residues of the AMPK-α subunit. Indirectly, RONS may activate AMPK by reducing mitochondrial ATP synthesis, leading to an increased AMP:ATP ratio and subsequent Thr(172)-AMPK phosphorylation by the two main AMPK kinases: LKB1 and CaMKKβ. In presence of RONS the rate of Thr(172)-AMPK dephosphorylation is reduced. RONS may activate LKB1 through Sestrin2 and SIRT1 (NAD(+)/NADH.H(+)-dependent deacetylase). RONS may also activate CaMKKβ by direct modification of RONS sensitive motifs and, indirectly, by activating the ryanodine receptor (Ryr) to release Ca(2+). Both too high (hypoxia) and too low (ingestion of antioxidants) RONS levels may lead to Ser(485)-AMPKα1/Ser(491)-AMPKα2 phosphorylation causing inhibition of Thr(172)-AMPKα phosphorylation. Exercise training increases muscle antioxidant capacity. When the same high-intensity training is applied to arm and leg muscles, arm muscles show signs of increased oxidative stress and reduced mitochondrial biogenesis, which may be explained by differences in RONS-sensing mechanisms and basal antioxidant capacities between arm and leg muscles. Efficient adaptation to exercise training requires optimal exposure to pulses of RONS. Inappropriate training stimulus may lead to excessive RONS formation, oxidative inactivation of AMPK and reduced adaptation or even maladaptation. Theoretically, exercise programs should be designed taking into account the intrinsic properties of different skeletal muscles, the specific RONS induction and the subsequent signaling responses. Copyright © 2016 Elsevier Inc. All rights reserved.

49 CFR 30.9 - Citizenship: Direct or indirect control.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false Citizenship: Direct or indirect control. 30.9 Section 30.9 Transportation Office of the Secretary of Transportation DENIAL OF PUBLIC WORKS CONTRACTS TO... title to 50 percent or more of the stock of the contractor or subcontractor is held subject to trust or...

The association between attention control, anxiety, and depression: the indirect effects of repetitive negative thinking and mood recovery.

PubMed

Kertz, Sarah J; Stevens, Kimberly T; Klein, Keith P

2017-07-01

Attention control deficits and repetitive negative thinking (RNT; i.e., rumination) may be key factors in the development and persistence of depression and anxiety, although their role in symptom development remains poorly understood. This represents a gap in the literature, as interventions targeting attention control and associated RNT may enhance interventions and prevent costly relapse. The current study was designed to examine the serial indirect effects of transdiagnostic RNT and negative affect recovery following a lab-induced stressor on the association between attention control deficits and trait anxiety and depression. Participants were N = 583 university students who completed validated measures of RNT, anxiety, depression, and mood ratings pre- and post-stressor. Stress was induced using a modified version of the Trier Social Stress Test. Results of cross-sectional indirect effects models indicated that RNT and mood recovery explained the association between attention control deficits and trait anxiety and depression. Results from reversed models indicated that only the indirect effect of RNT was significant. Findings suggest that RNT and mood recovery processes play an important role in explaining anxiety and depression symptoms. Additional work is needed to examine their role in symptom development and maintenance over time.

The Effect of Spaceflight on the Ultrastructure of the Cerebellum

NASA Technical Reports Server (NTRS)

Holstein, Gay R.; Martinelli, Giorgio P.

2003-01-01

In weightlessness, astronauts and cosmonauts may experience postural illusions as well as motion sickness symptoms known as the space adaptation syndrome. Upon return to Earth, they have irregularities in posture and balance. The adaptation to microgravity and subsequent re-adaptation to Earth occurs over several days. At the cellular level, a process called neuronal plasticity may mediate this adaptation. The term plasticity refers to the flexibility and modifiability in the architecture and functions of the nervous system. In fact, plastic changes are thought to underlie not just behavioral adaptation, but also the more generalized phenomena of learning and memory. The goal of this experiment was to identify some of the structural alterations that occur in the rat brain during the sensory and motor adaptation to microgravity. One brain region where plasticity has been studied extensively is the cerebellar cortex-a structure thought to be critical for motor control, coordination, the timing of movements, and, most relevant to the present experiment, motor learning. Also, there are direct as well as indirect connections between projections from the gravity-sensing otolith organs and several subregions of the cerebellum. We tested the hypothesis that alterations in the ultrastructural (the structure within the cell) architecture of rat cerebellar cortex occur during the early period of adaptation to microgravity, as the cerebellum adapts to the absence of the usual gravitational inputs. The results show ultrastructural evidence for neuronal plasticity in the central nervous system of adult rats after 24 hours of spaceflight. Qualitative studies conducted on tissue from the cerebellar cortex (specifically, the nodulus of the cerebellum) indicate that ultrastructural signs of plasticity are present in the cerebellar zones that receive input from the gravity-sensing organs in the inner ear (the otoliths). These changes are not observed in this region in cagematched ground control animals. The specific changes include the formation of lamellar bodies, profoundly enlarged Purkinje cell mitochondria, the presence of inter-neuronal cellular protrusions in the molecular layer, and signs of degeneration in the distal dendrites of the Purkinje cells. Since these morphologic signs are not apparent in the control animals, they are not likely to be due to caging or tissue processing effects. The particular nature of the structural alterations in the nodulus, most notably the formation of lamellar bodies and the presence of degeneration, further suggests that excitotoxicity (damaging overstimulation of neurons) may play a role in the short-term neural response to spaceflight. These findings suggest a structural basis for the neuronal and synaptic plasticity accompanying the central nervous system response to altered gravity and help identify the cellular bases underlying the vestibular abnormalities experienced by astronauts during periods of adaptation and re-adaptation to different gravitational forces. Also, since the short- and long-term changes in neural structure occurring during such periods of adaptation resemble the neuronal alterations that occur in some neurologic disorders such as stroke, these findings may offer guidance in the development of strategies for rehabilitation and treatment of such disorders.

Neuromuscular adaptations to training, injury and passive interventions: implications for running economy.

PubMed

Bonacci, Jason; Chapman, Andrew; Blanch, Peter; Vicenzino, Bill

2009-01-01

Performance in endurance sports such as running, cycling and triathlon has long been investigated from a physiological perspective. A strong relationship between running economy and distance running performance is well established in the literature. From this established base, improvements in running economy have traditionally been achieved through endurance training. More recently, research has demonstrated short-term resistance and plyometric training has resulted in enhanced running economy. This improvement in running economy has been hypothesized to be a result of enhanced neuromuscular characteristics such as improved muscle power development and more efficient use of stored elastic energy during running. Changes in indirect measures of neuromuscular control (i.e. stance phase contact times, maximal forward jumps) have been used to support this hypothesis. These results suggest that neuromuscular adaptations in response to training (i.e. neuromuscular learning effects) are an important contributor to enhancements in running economy. However, there is no direct evidence to suggest that these adaptations translate into more efficient muscle recruitment patterns during running. Optimization of training and run performance may be facilitated through direct investigation of muscle recruitment patterns before and after training interventions. There is emerging evidence that demonstrates neuromuscular adaptations during running and cycling vary with training status. Highly trained runners and cyclists display more refined patterns of muscle recruitment than their novice counterparts. In contrast, interference with motor learning and neuromuscular adaptation may occur as a result of ongoing multidiscipline training (e.g. triathlon). In the sport of triathlon, impairments in running economy are frequently observed after cycling. This impairment is related mainly to physiological stress, but an alteration in lower limb muscle coordination during running after cycling has also been observed. Muscle activity during running after cycling has yet to be fully investigated, and to date, the effect of alterations in muscle coordination on running economy is largely unknown. Stretching, which is another mode of training, may induce acute neuromuscular effects but does not appear to alter running economy. There are also factors other than training structure that may influence running economy and neuromuscular adaptations. For example, passive interventions such as shoes and in-shoe orthoses, as well as the presence of musculoskeletal injury, may be considered important modulators of neuromuscular control and run performance. Alterations in muscle activity and running economy have been reported with different shoes and in-shoe orthoses; however, these changes appear to be subject-specific and non-systematic. Musculoskeletal injury has been associated with modifications in lower limb neuromuscular control, which may persist well after an athlete has returned to activity. The influence of changes in neuromuscular control as a result of injury on running economy has yet to be examined thoroughly, and should be considered in future experimental design and training analysis.

Modeling learning in brain stem and cerebellar sites responsible for VOR plasticity

NASA Technical Reports Server (NTRS)

Quinn, K. J.; Didier, A. J.; Baker, J. F.; Peterson, B. W.

1998-01-01

A simple model of vestibuloocular reflex (VOR) function was used to analyze several hypotheses currently held concerning the characteristics of VOR plasticity. The network included a direct vestibular pathway and an indirect path via the cerebellum. An optimization analysis of this model suggests that regulation of brain stem sites is critical for the proper modification of VOR gain. A more physiologically plausible learning rule was also applied to this network. Analysis of these simulation results suggests that the preferred error correction signal controlling gain modification of the VOR is the direct output of the accessory optic system (AOS) to the vestibular nuclei vs. a signal relayed through the cerebellum via floccular Purkinje cells. The potential anatomical and physiological basis for this conclusion is discussed, in relation to our current understanding of the latency of the adapted VOR response.

A "Kane's Dynamics" Model for the Active Rack Isolation System

NASA Astrophysics Data System (ADS)

Rupert, J. K.; Hampton, R. D.; Beech, G. S.

2005-02-01

In the late 1980s, microgravity researchers began to voice their concern that umbilical-transmitted energy could significantly degrade the acceleration environment of microgravity space science experiments onboard manned spacecraft. Since umbilicals are necessary for many experiments, control designers began to seek ways to compensate for these "indirect" disturbances. Hampton, et al., used the Kane s method to develop a model of the active rack isolation system (ARIS) that includes (1) actuator control forces, (2) direct disturbance forces, and (3) indirect, actuator-transmitted disturbances. Their model does not, however, include the indirect, umbilical-transmitted disturbances. Since the umbilical stiffnesses are not negligible, these indirect disturbances must be included in the model. Until the umbilicals have been appropriately included, the model will be incomplete. This Technical Memorandum presents a nonlinear model of ARIS with umbilicals included. Model verification was achieved by utilizing two commercial-off-the-shelf software tools. Various forces and moments were applied to the model to yield simulated responses of the system. Plots of the simulation results show how various critical points on an ARIS-outfitted international standard payload rack behave under the application of direct disturbances, indirect disturbances, and control forces. Simulations also show system response to a variety of initial conditions.

Bovine somatotropin and lactation: from basic science to commercial application.

PubMed

Bauman, D E

1999-10-01

Bovine somatotropin (bST) results in increased milk yield and an unprecedented improvement in efficiency. Beginning in the 1930s to present day, investigations have examined animal-related factors such as nutrition, bioenergetics, metabolism, health and well being and consumer-related factors such as milk quality, manufacturing characteristics, and product safety. Overall, bST is a homeorhetic control involved in orchestrating many physiological processes. Direct effects involve adaptations in many tissues and the metabolism of all nutrient classes--carbohydrates, lipids, protein, and minerals. Mechanisms include alterations in key enzymes, intracellular signal transduction systems, and tissue response to homeostatic signals. Indirect effects involve the mammary gland and are thought to be mediated by the insulin-like growth factor (IGF) system. Specific changes include increased cellular rates of milk synthesis and enhanced maintenance of secretory cells. Indirect effects are modulated by environment and management factors, especially nutritional status. This modulation is a central component in allowing ST to play a key role in regulating nutrient utilization across a range of physiological situations. U.S. commercial use began in 1994, and adoption has been extensive. From a consumer perspective, bST was unique, and special interest groups loudly predicted dire consequences. However, introduction of bST had no impact on milk consumption, and milk labeled as recombinant bST-free occupies a minor niche market. From a producer perspective, commercial use verified scientific studies and enhanced net farm income. Overall, ST is a key homeorhetic control regulating nutrient partitioning, and the ST/IGF system plays a key role in animal performance and well being across a range of physiological situations.

In pursuit of resilience: stress, epigenetics, and brain plasticity.

PubMed

McEwen, Bruce S

2016-06-01

The brain is the central organ for adaptation to experiences, including stressors, which are capable of changing brain architecture as well as altering systemic function through neuroendocrine, autonomic, immune, and metabolic systems. Because the brain is the master regulator of these systems, as well as of behavior, alterations in brain function by chronic stress can have direct and indirect effects on cumulative allostatic overload, which refers to the cost of adaptation. There is much new knowledge on the neural control of systemic physiology and the feedback actions of physiologic mediators on brain regions regulating higher cognitive function, emotional regulation, and self-regulation. The healthy brain has a considerable capacity for resilience, based upon its ability to respond to interventions designed to open "windows of plasticity" and redirect its function toward better health. As a result, plasticity-facilitating treatments should be given within the framework of a positive behavioral intervention; negative experiences during this window may even make matters worse. Indeed, there are no magic bullets and drugs cannot substitute for targeted interventions that help an individual become resilient, of which mindfulness-based stress reduction and meditation are emerging as useful tools. © 2016 New York Academy of Sciences.

Policy improvement by a model-free Dyna architecture.

PubMed

Hwang, Kao-Shing; Lo, Chia-Yue

2013-05-01

The objective of this paper is to accelerate the process of policy improvement in reinforcement learning. The proposed Dyna-style system combines two learning schemes, one of which utilizes a temporal difference method for direct learning; the other uses relative values for indirect learning in planning between two successive direct learning cycles. Instead of establishing a complicated world model, the approach introduces a simple predictor of average rewards to actor-critic architecture in the simulation (planning) mode. The relative value of a state, defined as the accumulated differences between immediate reward and average reward, is used to steer the improvement process in the right direction. The proposed learning scheme is applied to control a pendulum system for tracking a desired trajectory to demonstrate its adaptability and robustness. Through reinforcement signals from the environment, the system takes the appropriate action to drive an unknown dynamic to track desired outputs in few learning cycles. Comparisons are made between the proposed model-free method, a connectionist adaptive heuristic critic, and an advanced method of Dyna-Q learning in the experiments of labyrinth exploration. The proposed method outperforms its counterparts in terms of elapsed time and convergence rate.

Direct and indirect pathways for choosing objects and actions.

PubMed

Hikosaka, Okihide; Kim, Hyoung F; Amita, Hidetoshi; Yasuda, Masaharu; Isoda, Masaki; Tachibana, Yoshihisa; Yoshida, Atsushi

2018-02-23

A prominent target of the basal ganglia is the superior colliculus (SC) which controls gaze orientation (saccadic eye movement in primates) to an important object. This 'object choice' is crucial for choosing an action on the object. SC is innervated by the substantia nigra pars reticulata (SNr) which is controlled mainly by the caudate nucleus (CD). This CD-SNr-SC circuit is sensitive to the values of individual objects and facilitates saccades to good objects. The object values are processed differently in two parallel circuits: flexibly by the caudate head (CDh) and stably by the caudate tail (CDt). To choose good objects, we need to reject bad objects. In fact, these contrasting functions are accomplished by the circuit originating from CDt: The direct pathway focuses on good objects and facilitates saccades to them; the indirect pathway focuses on bad objects and suppresses saccades to them. Inactivation of CDt deteriorated the object choice, because saccades to bad objects were no longer suppressed. This suggests that the indirect pathway is important for object choice. However, the direct and indirect pathways for 'object choice', which aim at the same action (i.e., saccade), may not work for 'action choice'. One possibility is that circuits controlling different actions are connected through the indirect pathway. Additional connections of the indirect pathway with brain areas outside the basal ganglia may also provide a wider range of behavioral choice. In conclusion, basal ganglia circuits are composed of the basic direct/indirect pathways and additional connections and thus have acquired multiple functions. © 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Fuel-Burning Technology Alternatives for the Army.

DTIC Science & Technology

1985-01-01

control 0.85 2,287,000 Flue gas desulfurization 0.68 3,410,000 Total 12,478,000 *Capital cost estimate...34......... . . Particulate and sulfur dioxide control are needed. A baghouse and flue gas desulfurization (FD) scrubber system must be installed. Each item’s cost in...direct cost) Contingency (20% of 1,253,000 direct and indirect costs) Subtotal 7,518,000 Particulate control 1,342,000 Flue gas desulfurization

Climate change adaptation and mitigation options a guide for natural resource managers in southern forest ecosystems

Treesearch

James M. Vose; Kier D. Klepzig

2014-01-01

The rapid pace of climate change and its direct and indirect effects on forest ecosystems present a pressing need for better scientific understanding and the development of new science-management partnerships. Understanding the effects of stressors and disturbances (including climatic variability), and developing and testing science-based management options to deal...

School Disaster Planning for Children with Disabilities: A Critical Review of the Literature

ERIC Educational Resources Information Center

Boon, Helen J.; Brown, Lawrence H.; Tsey, Komla; Speare, Richard; Pagliano, Paul; Usher, Kim; Clark, Brenton

2011-01-01

Human systems have to adapt to climate change and the natural disasters predicted to increase in frequency as a result. These disasters have both direct and indirect health effects. Certain groups, the poor, the elderly, children and those with disabilities are set to be more seriously impacted by disasters because of their greater inherent…

Culturally Appropriate Mentoring for Horn of African Young People in Australia

ERIC Educational Resources Information Center

Griffiths, Megan; Sawrikar, Pooja; Muir, Kristy

2009-01-01

Little is known about how to appropriately adapt mentoring programs for young people from the Horn of Africa, even though they have been arriving in Australia in significantly increasing numbers. These young people face unique challenges as a result of their age, ethnicity, migration and direct/indirect trauma experiences. The results of this…

Marbles: A Means of Introducing Students to Scattering Concepts

ERIC Educational Resources Information Center

Bender, K. M.; Westphal, P. S.; Ramsier, R. D.

2008-01-01

The purpose of this activity is to introduce students to concepts of short-range and long-range scattering, and engage them in using indirect measurements and probabilistic models. The activity uses simple and readily available apparatus, and can be adapted for use with secondary level students as well as those in general physics courses or…

Perceptions of Services and Resources as Mediators of Depression among Parents of Children with Developmental Disabilities.

ERIC Educational Resources Information Center

Herman, Sandra E.; Marcenko, Maureen O.

1997-01-01

This study examined effects of resource perceptions and respite use in a theoretical model of adaptation with 72 parents of children with developmental disabilities. Amount and quality of respite services indirectly affected parental depression. Both quality and respite use were related to helpfulness of the parent's social network. The strongest…

Quality Assurance Processes in Finnish Universities: Direct and Indirect Outcomes and Organisational Conditions

ERIC Educational Resources Information Center

Haapakorpi, Arja

2011-01-01

In Finland, quality assurance related to the Bologna process has been adapted to existing systems of higher education at the national level and a form of implementation is also recognised at the level of the higher education institution. In universities, varied outcomes of quality assurance are based on interaction of organisational structures,…

Aberrant pain perception in direct and indirect non-suicidal self-injury: an empirical test of Joiner's interpersonal theory.

PubMed

St Germain, Sarah A; Hooley, Jill M

2013-08-01

Using a community sample (N=148) we examined pressure pain perception in 3 study groups--people who engaged in non-suicidal self-injury, people who engaged in indirect forms of self-injury, and non-self-injuring controls. In so doing we tested hypotheses derived from Joiner's (2005) interpersonal theory of suicide. Consistent with previous studies and with Joiner's model, people who engaged in NSSI endured pain for significantly longer than non-self-injuring controls. Importantly, pain endurance in the Indirect self-injury group was comparable to that found in the NSSI group and significantly elevated relative to controls. This pattern of results suggests that abnormal pain perception may not be specific to forms of self-injury (e.g., NSSI) that involve immediate physical pain (e.g., cutting). Our findings further suggest that the concept of acquired capability for suicide might have relevance for both direct and indirect forms of self-injurious behavior. Copyright © 2013 Elsevier Inc. All rights reserved.

The indirect effect of panic disorder on smoking cognitions via difficulties in emotion regulation.

PubMed

Yang, Min-Jeong; Zvolensky, Michael J; Leyro, Teresa M

2017-09-01

Panic disorder (PD) and cigarette smoking are highly comorbid and associated with worse panic and smoking outcomes. Smoking may become an overlearned automatized response to relieve panic-like withdrawal distress, leading to corresponding smoking cognitions, which contribute to its reinforcing properties and difficultly abstaining. Difficulties in emotion regulation (ER) may underlie this relation such that in the absence of adaptive emotion regulatory strategies, smokers with PD may more readily rely upon smoking to manage affective distress. In the current study, the indirect relation between PD status and smoking cognitions through ER difficulties was examined among daily smokers (N=74). We found evidence for an indirect relation between PD status and negative affect, addictive and habitual smoking motives, and anticipating smoking will result in negative reinforcement and personal harm, through self-reported difficulties with ER. Our findings are aligned with theoretical models on anxiety and smoking, and suggest that reports of greater smoking cognitions may be due to ER difficulties. Copyright © 2017. Published by Elsevier Ltd.

Direct and Indirect Influence of Altruistic Behavior in a Social Network.

PubMed

Liu, Pei-Pei; Safin, Vasiliy; Yang, Barry; Luhmann, Christian C

2015-01-01

Prior research has suggested that recipients of generosity behave more generously themselves (a direct social influence). In contrast, there is conflicting evidence about the existence of indirect influence (i.e., whether interacting with a recipient of generosity causes one to behave more generously), casting doubt on the possibility that altruistic behavior can cascade through social networks. The current study investigated how far selfish and generous behavior can be transmitted through social networks and the cognitive mechanisms that underlie such transmission. Participants played a sequence of public goods games comprising a chain network. This network is advantageous because it permits only a single, unambiguous path of influence. Furthermore, we experimentally manipulated the behavior of the first link in the chain to be either generous or selfish. Results revealed the presence of direct social influence, but no evidence for indirect influence. Results also showed that selfish behavior exerted a substantially greater influence than generous behavior. Finally, expectations about future partners' behavior strongly mediated the observed social influence, suggesting an adaptive basis for such influence.

Detection of antibodies in human serum using trimellityl-erythrocytes: direct and indirect haemagglutination and haemolysis.

PubMed

Turner, E S; Pruzansky, J J; Patterson, R; Zeiss, C R; Roberts, M

1980-02-01

Utilizing trimellityl-erythrocytes (TM-E), antibodies were detected in sera of seven workers with trimellitic anhydride (TMA) induced airway syndromes by direct haemagglutination, indirect haemagglutination with anti-human IgG, IgA or IgM or by haemolysis. Detectable levels of antibody were obtained with all three methods. The most sensitive technique was indirect haemagglutination using anti-IgG. When added as an inhibitor, TM-human serum albumin produced a 10- to 800-fold reduction in titres. TM-ovalbumin of similar epitope density was less inhibitory and sodium trimellitate the least inhibitory on a molar basis. All of the assays using haptenized human red cells were also capable of detecting anti-TM antibodies in Rhesus monkeys whose airways had been exposed to TMA. These assays are useful for detecting anti-TM antibodies and may also be adapted to demonstrate antibodies induced against other inhaled haptens in sera of environmentally exposed individuals or in animal models of such exposure.

Parental coping, depressive symptoms, and children's asthma control and school attendance in low-income, racially, and ethnically diverse urban families.

PubMed

Rodríguez, Erin M; Kumar, Harsha; Alba-Suarez, Juliana; Sánchez-Johnsen, Lisa

2017-10-01

Low-income urban children of color are at elevated risk for poor asthma control. This cross-sectional study examined associations among parents' coping (primary control, secondary control, and disengagement), parental depressive symptoms, and children's asthma outcomes (asthma control and school attendance) in a predominantly low-income, racially/ethnically diverse sample of families. Parents (N = 78; 90% female) of children (33% female; 46% Black; 38% Latino) aged 5-17 years (M = 9.5 years) reported on their own coping and depressive symptoms, their child's asthma control, and full and partial days of school missed due to asthma. Parents' secondary control coping (i.e., coping efforts to accommodate/adapt to asthma-related stressors) was negatively correlated, and disengagement coping (i.e. coping efforts to avoid/detach from stressors) was positively correlated, with their depressive symptoms. Secondary control coping was also correlated with fewer partial days of school missed. Primary control coping (i.e., coping efforts to change stressors) was not associated with depressive symptoms or asthma outcomes. Parents' depressive symptoms were also positively correlated with poorer asthma control and partial days of school missed. Regression models showed direct and indirect effects of secondary control and disengagement coping on asthma outcomes via depressive symptoms, after controlling for demographic factors. Parents' secondary control and disengagement coping are related to children's asthma outcomes. Secondary control coping may support parents' mental health and children's asthma control in low-income urban families.

Genome-Wide Association Analysis of Adaptation Using Environmentally Predicted Traits

PubMed Central

van Zanten, Martijn

2015-01-01

Current methods for studying the genetic basis of adaptation evaluate genetic associations with ecologically relevant traits or single environmental variables, under the implicit assumption that natural selection imposes correlations between phenotypes, environments and genotypes. In practice, observed trait and environmental data are manifestations of unknown selective forces and are only indirectly associated with adaptive genetic variation. In theory, improved estimation of these forces could enable more powerful detection of loci under selection. Here we present an approach in which we approximate adaptive variation by modeling phenotypes as a function of the environment and using the predicted trait in multivariate and univariate genome-wide association analysis (GWAS). Based on computer simulations and published flowering time data from the model plant Arabidopsis thaliana, we find that environmentally predicted traits lead to higher recovery of functional loci in multivariate GWAS and are more strongly correlated to allele frequencies at adaptive loci than individual environmental variables. Our results provide an example of the use of environmental data to obtain independent and meaningful information on adaptive genetic variation. PMID:26496492

Evaluating Change in Beliefs About the Importance/Control of Thoughts as a Mediator of CBM-I and Responses to an ICT Stressor.

PubMed

Clerkin, Elise M; Magee, Joshua C; Parsons, E Marie

2014-10-01

This study evaluated an adaptation of a Cognitive Bias Modification-Interpretation (CBM-I) procedure designed to shift interpretations of intrusive thoughts related to beliefs about the Importance and Control of Thoughts (ICT). Individuals high in the ICT belief domain were randomly assigned to one of two conditions: (a) a positive (n = 38) condition in which scenarios about intrusive thoughts were repeatedly paired with benign interpretations; or (b) a control (n = 39) condition in which scenarios about intrusive thoughts were paired with 50% benign and 50% threatening interpretations. Further, participants engaged in an ICT stressor task. Structural equation modeling with bias-corrected bootstrapping was used to examine the effects of training on ICT-relevant interpretations, beliefs, and ICT stressor responding. As predicted, individuals in a positive (vs. control) training condition reported decreases in ICT-relevant interpretations and beliefs. Further, there was a small, statistically significant indirect (i.e., mediated) effect of training on measures of ICT stressor responding, which occurred via decreases in ICT-relevant beliefs. In sum, results indicate that training was effective in influencing interpretations and beliefs tied to Importance/Control of Thoughts and that there may be clinical utility to shifting this belief domain.

Evaluating Change in Beliefs About the Importance/Control of Thoughts as a Mediator of CBM-I and Responses to an ICT Stressor

PubMed Central

Clerkin, Elise M.; Magee, Joshua C.; Parsons, E. Marie

2014-01-01

This study evaluated an adaptation of a Cognitive Bias Modification-Interpretation (CBM-I) procedure designed to shift interpretations of intrusive thoughts related to beliefs about the Importance and Control of Thoughts (ICT). Individuals high in the ICT belief domain were randomly assigned to one of two conditions: (a) a positive (n = 38) condition in which scenarios about intrusive thoughts were repeatedly paired with benign interpretations; or (b) a control (n = 39) condition in which scenarios about intrusive thoughts were paired with 50% benign and 50% threatening interpretations. Further, participants engaged in an ICT stressor task. Structural equation modeling with bias-corrected bootstrapping was used to examine the effects of training on ICT-relevant interpretations, beliefs, and ICT stressor responding. As predicted, individuals in a positive (vs. control) training condition reported decreases in ICT-relevant interpretations and beliefs. Further, there was a small, statistically significant indirect (i.e., mediated) effect of training on measures of ICT stressor responding, which occurred via decreases in ICT-relevant beliefs. In sum, results indicate that training was effective in influencing interpretations and beliefs tied to Importance/Control of Thoughts and that there may be clinical utility to shifting this belief domain. PMID:25414811

Once bitten, twice shy: experienced regret and non-adaptive choice switching

PubMed Central

Cosulich, Anna; Ferrante, Donatella

2015-01-01

When a good decision leads to a bad outcome, the experience of regret can bias subsequent choices: people are less likely to select the regret-producing alternative a second time, even when it is still objectively the best alternative (non-adaptive choice switching). The first study presented herein showed that nearly half of participants experiencing regret rejected a previous alternative they had recognized as the best one, and chose a non-optimal alternative instead. The second study investigated the mechanism underlying this bias, and results supported the hypothesis that this non-adaptive choice switching is caused by inhibition of the previous decision (direct effect of experienced regret), rather than by increased sensitivity to anticipated regret in subsequent choices (indirect effect of experienced regret mediated by anticipated regret). PMID:26157618

Indirect immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays (ELISAs) and IgM capture ELISA for detection of antibodies to lipopolysaccharide in adult typhoid fever patients in Pakistan.

PubMed

Sippel, J; Bukhtiari, N; Awan, M B; Krieg, R; Duncan, J F; Karamat, K A; Malik, I A; Igbal, L M; Legters, L

1989-06-01

Sera from 339 adult febrile patients in Pakistan were tested for antibodies to Salmonella typhi lipopolysaccharide by indirect immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assay (ELISA) and IgM capture ELISA. A total of 55 patients had S. typhi cultured from their blood, 20 had S. typhi cultured from their stool, 24 were blood or stool culture positive for S. paratyphi A, 41 were culture negative but clinically diagnosed as having enteric fever, 41 had gastrointestinal or urinary tract infections, 41 were clinically diagnosed as having malaria, 20 were smear-positive patients with malaria, 58 had respiratory infections, and the remaining 39 individuals were placed in a miscellaneous group who did not have Salmonella infection. The sensitivities of the indirect IgG ELISA, indirect IgM ELISA, and IgM capture ELISA determined with specimens obtained from the blood culture-positive patients with typhoid fever (positive controls) were 80, 64, and 62%, respectively. The specificities of the assays determined with sera from the patients with respiratory infections (negative controls) were 95, 95, and 97%, respectively. The percentage of smear-positive patients with malaria who were positive by these assays was lower than that in the negative control group. The percentages of individuals in the other patient categories who were positive by these tests were between those obtained with the positive and negative controls. Of the positive controls, 26 were positive by both IgM assays, 9 were IgM positive only by indirect ELISA, and 8 were IgM positive only by IgM capture ELISA. A total of 70% of the positive control patients who were tested for O agglutinins by the Widal tube agglutination assay were positive; however, 29% of the negative control patients were also positive. The indirect IgG ELISA was the single most effective test for the serodiagnosis of typhoid fever in this population.

Indirect immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays (ELISAs) and IgM capture ELISA for detection of antibodies to lipopolysaccharide in adult typhoid fever patients in Pakistan.

PubMed Central

Sippel, J; Bukhtiari, N; Awan, M B; Krieg, R; Duncan, J F; Karamat, K A; Malik, I A; Igbal, L M; Legters, L

1989-01-01

Sera from 339 adult febrile patients in Pakistan were tested for antibodies to Salmonella typhi lipopolysaccharide by indirect immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assay (ELISA) and IgM capture ELISA. A total of 55 patients had S. typhi cultured from their blood, 20 had S. typhi cultured from their stool, 24 were blood or stool culture positive for S. paratyphi A, 41 were culture negative but clinically diagnosed as having enteric fever, 41 had gastrointestinal or urinary tract infections, 41 were clinically diagnosed as having malaria, 20 were smear-positive patients with malaria, 58 had respiratory infections, and the remaining 39 individuals were placed in a miscellaneous group who did not have Salmonella infection. The sensitivities of the indirect IgG ELISA, indirect IgM ELISA, and IgM capture ELISA determined with specimens obtained from the blood culture-positive patients with typhoid fever (positive controls) were 80, 64, and 62%, respectively. The specificities of the assays determined with sera from the patients with respiratory infections (negative controls) were 95, 95, and 97%, respectively. The percentage of smear-positive patients with malaria who were positive by these assays was lower than that in the negative control group. The percentages of individuals in the other patient categories who were positive by these tests were between those obtained with the positive and negative controls. Of the positive controls, 26 were positive by both IgM assays, 9 were IgM positive only by indirect ELISA, and 8 were IgM positive only by IgM capture ELISA. A total of 70% of the positive control patients who were tested for O agglutinins by the Widal tube agglutination assay were positive; however, 29% of the negative control patients were also positive. The indirect IgG ELISA was the single most effective test for the serodiagnosis of typhoid fever in this population. PMID:2754002

Real-World Evaluation of Direct and Indirect Economic Burden Among Endometriosis Patients in the United States.

PubMed

Soliman, Ahmed M; Surrey, Eric; Bonafede, Machaon; Nelson, James K; Castelli-Haley, Jane

2018-03-01

The prevalence of endometriosis and the need for treatment in the USA has led to the need to explore the contemporary cost burden associated with the disease. This retrospective cohort study compared direct and indirect healthcare costs in patients with endometriosis to a control group without endometriosis. Women aged 18-49 years with endometriosis (date of initial diagnosis = index date) were identified in the Truven Health MarketScan ® Commercial database between 2010 and 2014 and female control patients without endometriosis were matched by age and index year. The following outcomes were compared: healthcare resource utilization (HRU) during the 12-month pre- and post-index periods (including inpatient admissions, pharmacy claims, emergency room visits, physician office visits, and obstetrics/gynecology visits), annual direct (medical and pharmacy) and indirect (absenteeism, short-term disability, and long-term disability) healthcare costs during the 12-month post-index period (in 2014 US$). Multivariate analyses were conducted to estimate annual total direct and indirect costs, controlling for demographics, pre-index clinical characteristics, and pre-index healthcare costs. Overall, 113,506 endometriosis patients and 927,599 controls were included. Endometriosis patients had significantly higher HRU during both the pre- and post-index periods compared to controls (p < 0.0001, all categories of HRU). Approximately two-thirds of endometriosis patients underwent an endometriosis-related surgical procedure (including laparotomy, laparoscopy, hysterectomy, oophorectomy, and other excision/ablation procedures) in the first 12 months post-index. Mean annual total adjusted direct costs per endometriosis patient during the 12-month post-index period was over three times higher than that for a non-endometriosis control [$16,573 (standard deviation (SD) = $21,336) vs. $4733 (SD = $14,833); p < 0.005]. On average, incremental direct and indirect 12-month costs per endometriosis patient were $10,002 and $2132 compared to their matched controls (p < 0.005). Endometriosis patients incurred significantly higher direct and indirect healthcare costs than non-endometriosis patients. AbbVie Inc.

Relationship between indirect blood pressure and various stages of chronic kidney disease in cats.

PubMed

Hori, Yasutomo; Heishima, Yasuhiro; Yamashita, Yohei; Isayama, Noriko; Kanno, Nobuyuki; Nakamura, Kensuke; Iguchi, Masayuki; Ibaragi, Toshiki; Onodera, Hideyuki; Aramaki, Yoshitaka; Hirakawa, Atsushi; Yamano, Shigeki; Katagi, Michio; Kitade, Akihito; Sawada, Tamotsu

2018-03-24

Chronic kidney disease (CKD) is a common cause of secondary systemic hypertension in cats. We investigated the relationship between indirect blood pressure and the prevalence of systemic hypertension in various CKD stages in cats. Client-owned cats (24 control cats and 77 cats with CKD) were included. Biochemical examinations of plasma were conducted by a commercial laboratory. Diseased cats were divided into two groups based on the International Renal Interest Society (IRIS) guidelines (II and III-IV). Indirect blood pressure was measured using an oscillometric technique. Severe hypertension was diagnosed if systolic blood pressure (SBP) was ≥180 mmHg. Indirect blood pressures were significantly higher in IRIS stage III-IV than in the control cats. Of 77 cats with CKD, 25 (32.5%) had severe hypertension. The frequency of severe hypertension increased with an increase in IRIS stage; 0% in the controls, 27.6% in the IRIS stage II, and 47.4% in the IRIS stage III-IV, respectively. The indirect SBP was weakly correlated with urea nitrogen (r=0.27) and creatinine (r=0.23) concentrations in plasma. Binary logistic regression analysis showed that if plasma creatinine concentration is >3.7 mg/dl, cats with CKD had an increased risk for developing severe hypertension (P<0.001). Our results suggest that indirect blood pressure was correlated with the severity of CKD, and the prevalence of severe hypertension increased in cats with severe CKD. The risk of severe hypertension may be high in cats with severe CKD.

Development of autistic children based on maternal responses to the Autism Behavior Checklist.

PubMed

Tamanaha, Ana Carina; Perissinoto, Jacy; Chiari, Brasilia Maria

2008-01-01

language and speech-language intervention. to evaluate the development process of autistic children, in a direct and indirect intervention context based on the responses of mothers to the Autism Behavior Checklist. the research sample consisted of 11 mothers of children diagnosed, according to the criteria established by the DSM IVtr (APA, 2002), with autism (six) and with Asperger Syndrome (five) and who were seen at the Investigation Laboratory of Global Developmental Disorders of the Federal University of São Paulo. These children were randomly divided into two groups: Six were receiving both direct and indirect intervention (TG), and five were receiving indirect intervention exclusively (OG). The Autism Behavior Checklist (Krug et al., 1993) was used, adapted to the Portuguese language by Marteleto (2003). This behavior checklist (57 items) allows the detailed description of non-adaptable characteristics regarding the following areas: sensory, use of the body and object, Language, Psycho-social and Relational. The questionnaire was filled in during an interview on three occasions: at the beginning of intervention, after six months and at the end of 12 months. after statistical analysis it was observed that there was a greater development in the total scores and in the areas of language, psycho-social and relational for the TG. This suggests a greater development pattern during the studied period for this group. the mothers of both groups observed behavioral changes. The better scores observed for the TG is probably related to the effectiveness of direct intervention, and not to the lack of attention of parents in the OG in recognizing behavioral changes in their children.

Pollinator Foraging Adaptation and Coexistence of Competing Plants

PubMed Central

Revilla, Tomás A.; Křivan, Vlastimil

2016-01-01

We use the optimal foraging theory to study coexistence between two plant species and a generalist pollinator. We compare conditions for plant coexistence for non-adaptive vs. adaptive pollinators that adjust their foraging strategy to maximize fitness. When pollinators have fixed preferences, we show that plant coexistence typically requires both weak competition between plants for resources (e.g., space or nutrients) and pollinator preferences that are not too biased in favour of either plant. We also show how plant coexistence is promoted by indirect facilitation via the pollinator. When pollinators are adaptive foragers, pollinator’s diet maximizes pollinator’s fitness measured as the per capita population growth rate. Simulations show that this has two conflicting consequences for plant coexistence. On the one hand, when competition between pollinators is weak, adaptation favours pollinator specialization on the more profitable plant which increases asymmetries in plant competition and makes their coexistence less likely. On the other hand, when competition between pollinators is strong, adaptation promotes generalism, which facilitates plant coexistence. In addition, adaptive foraging allows pollinators to survive sudden loss of the preferred plant host, thus preventing further collapse of the entire community. PMID:27505254

Local plant adaptation across a subarctic elevational gradient

PubMed Central

Kardol, Paul; De Long, Jonathan R.; Wardle, David A.

2014-01-01

Predicting how plants will respond to global warming necessitates understanding of local plant adaptation to temperature. Temperature may exert selective effects on plants directly, and also indirectly through environmental factors that covary with temperature, notably soil properties. However, studies on the interactive effects of temperature and soil properties on plant adaptation are rare, and the role of abiotic versus biotic soil properties in plant adaptation to temperature remains untested. We performed two growth chamber experiments using soils and Bistorta vivipara bulbil ecotypes from a subarctic elevational gradient (temperature range: ±3°C) in northern Sweden to disentangle effects of local ecotype, temperature, and biotic and abiotic properties of soil origin on plant growth. We found partial evidence for local adaption to temperature. Although soil origin affected plant growth, we did not find support for local adaptation to either abiotic or biotic soil properties, and there were no interactive effects of soil origin with ecotype or temperature. Our results indicate that ecotypic variation can be an important driver of plant responses to the direct effects of increasing temperature, while responses to covariation in soil properties are of a phenotypic, rather than adaptive, nature. PMID:26064553

Culvert analysis program for indirect measurement of discharge

USGS Publications Warehouse

Fulford, Janice M.; ,

1993-01-01

A program based on the U.S. Geological Survey (USGS) methods for indirectly computing peak discharges through culverts allows users to employ input data formats used by the water surface profile program (WSPRO). The program can be used to compute discharge rating surfaces or curves that describe the behavior of flow through a particular culvert or to compute discharges from measurements of upstream of the gradually varied flow equations and has been adapted slightly to provide solutions that minimize the need for the user to determine between different flow regimes. The program source is written in Fortran 77 and has been run on mini-computers and personal computers. The program does not use or require graphics capability, a color monitor, or a mouse.

[Climate change - physical and mental consequences].

PubMed

Bunz, Maxie; Mücke, Hans-Guido

2017-06-01

Climate change has already had a large influence on the human environmental system and directly or indirectly affects physical and mental health. Triggered by extreme meteorological conditions, for example, storms, floods, earth slides and heat periods, the direct consequences range from illnesses to serious accidents with injuries, or in extreme cases fatalities. Indirectly, a changed environment due to climate change affects, amongst other things, the cardiovascular system and respiratory tract, and can also cause allergies and infectious diseases. In addition, increasing confrontation with environmental impacts may cause negative psychological effects such as posttraumatic stress disorders and anxiety, but also aggression, distress and depressive symptoms. The extent and severity of the health consequences depend on individual pre-disposition, resilience, behaviour and adaptation.

Indirect Estimates of Jaw Muscle Tension in Children with Suspected Hypertonia, Children with Suspected Hypotonia, and Matched Controls

ERIC Educational Resources Information Center

Connaghan, Kathryn P.; Moore, Christopher A.

2013-01-01

Purpose: In this study, the authors compared indirect estimates of jaw-muscle tension in children with suspected muscle-tone abnormalities with age- and gender-matched controls. Method: Jaw movement and muscle activation were measured in children (ages 3 years, 11 months, to 10 years) with suspected muscle-tone abnormalities (Down syndrome or…

78 FR 3497 - KM Railways, LLC-Acquisition and Operation Exemption-DTE Chicago Fuels Terminal, LLC and DTE Coal...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-16

... Southern Railway Company in Chicago, Cook County, Ill.\\3\\ \\1\\ KMR is indirectly owned by noncarrier Koch Industries, Inc. (Koch). In addition to KMR, Koch also controls directly or indirectly three other Class III... Augustine Railroad, LLC), and Koch has sought Board authority to control a fourth Class III rail carrier...

The Direct and Indirect Effects of Parental Bonds, Parental Drug Use, and Self-Control on Adolescent Substance Use

ERIC Educational Resources Information Center

Hope,Trina L.; Whiteford, Scott W.

2005-01-01

Research indicates that parenting has important effects on adolescent substance use. However, the indirect effect of parenting on adolescent substance use via self-control is less understood. Gottfredson and Hirschi's General Theory of Crime has been extensively tested by researchers in the field of criminology, but the theory rarely has been used…

A "Kane's Dynamics" Model for the Active Rack Isolation System. Part 3; Addition of Umbilicals to the Nonlinear Model

NASA Technical Reports Server (NTRS)

Rupert, J. K.; Hampton, R. D.; Beech, G. S.

2005-01-01

In the late 1980s, microgravity researchers began to voice their concern that umbilical-transmitted energy could significantly degrade the acceleration environment of microgravity space science experiments onboard manned spacecraft. Since umbilicals are necessary for many experiments, control designers began to seek ways to compensate for these "indirect" disturbances. Hampton, et al., used the Kane s method to develop a model of the active rack isolation system (ARIS) that includes (1) actuator control forces, (2) direct disturbance forces, and (3) indirect, actuator-transmitted disturbances. Their model does not, however, include the indirect, umbilical-transmitted disturbances. Since the umbilical stiffnesses are not negligible, these indirect disturbances must be included in the model. Until the umbilicals have been appropriately included, the model will be incomplete. This Technical Memorandum presents a nonlinear model of ARIS with umbilicals included. Model verification was achieved by utilizing two commercial-off-the-shelf software tools. Various forces and moments were applied to the model to yield simulated responses of the system. Plots of the simulation results show how various critical points on an ARIS-outfitted international standard payload rack behave under the application of direct disturbances, indirect disturbances, and control forces. Simulations also show system response to a variety of initial conditions.

Vulnerability and adaptation to climate-related fire impacts in rural and urban interior Alaska

USGS Publications Warehouse

Trainor, Sarah F.; Calef, Monika; Natcher, David; Chapin, F. Stuart; McGuire, A. David; Huntington, Orville; Duffy, Paul A.; Rupp, T. Scott; DeWilde, La'Ona; Kwart, Mary; Fresco, Nancy; Lovecraft, Amy Lauren

2009-01-01

This paper explores whether fundamental differences exist between urban and rural vulnerability to climate-induced changes in the fire regime of interior Alaska. We further examine how communities and fire managers have responded to these changes and what additional adaptations could be put in place. We engage a variety of social science methods, including demographic analysis, semi-structured interviews, surveys, workshops and observations of public meetings. This work is part of an interdisciplinary study of feedback and interactions between climate, vegetation, fire and human components of the Boreal forest social–ecological system of interior Alaska. We have learned that although urban and rural communities in interior Alaska face similar increased exposure to wildfire as a result of climate change, important differences exist in their sensitivity to these biophysical, climate-induced changes. In particular, reliance on wild foods, delayed suppression response, financial resources and institutional connections vary between urban and rural communities. These differences depend largely on social, economic and institutional factors, and are not necessarily related to biophysical climate impacts per se. Fire management and suppression action motivated by political, economic or other pressures can serve as unintentional or indirect adaptation to climate change. However, this indirect response alone may not sufficiently reduce vulnerability to a changing fire regime. More deliberate and strategic responses may be required, given the magnitude of the expected climate change and the likelihood of an intensification of the fire regime in interior Alaska.

Successful Aging and Subjective Well-Being Among Oldest-Old Adults

PubMed Central

Cho, Jinmyoung; Martin, Peter; Poon, Leonard W.

2015-01-01

Purpose of the Study: This research integrates successful aging and developmental adaptation models to empirically define the direct and indirect effects of 2 distal (i.e., education and past life experiences) and 5 proximal influences (i.e., physical functioning, cognitive functioning, physical health impairment, social resources, and perceived economic status) on subjective well-being. The proximal influences involved predictors outlined in most extant models of successful aging (e.g., Rowe & Kahn, 1998 [Rowe, J. W., & Kahn, R. L. (1998). Successful aging. New York: Pantheon Books.]). Our model extends such models by including distal impact as well as interactions between distal and proximal impacts. Design and Methods: Data were obtained from 234 centenarians and 72 octogenarians in the Georgia Centenarian Study. Structural equation modeling was conducted with Mplus 6.1. Results: Results showed significant direct effects of physical health impairment and social resources on positive aspects of subjective well-being among oldest-old adults. We also found significant indirect effects of cognitive functioning and education on positive affect among oldest-old adults. Social resources mediated the relationship between cognitive functioning and positive affect; and cognitive functioning and social resources mediated the relationship between education and positive affect. In addition, physical health impairment mediated the relationship between cognitive functioning and positive affect; and cognitive functioning and physical health impairment mediated the relationship between education and positive affect. Implications: Integrating 2 different models (i.e., successful aging and developmental adaptation) provided a comprehensive view of adaptation from a developmental perspective. PMID:25112594

Adaptive control system having hedge unit and related apparatus and methods

NASA Technical Reports Server (NTRS)

Johnson, Eric Norman (Inventor); Calise, Anthony J. (Inventor)

2003-01-01

The invention includes an adaptive control system used to control a plant. The adaptive control system includes a hedge unit that receives at least one control signal and a plant state signal. The hedge unit generates a hedge signal based on the control signal, the plant state signal, and a hedge model including a first model having one or more characteristics to which the adaptive control system is not to adapt, and a second model not having the characteristic(s) to which the adaptive control system is not to adapt. The hedge signal is used in the adaptive control system to remove the effect of the characteristic from a signal supplied to an adaptation law unit of the adaptive control system so that the adaptive control system does not adapt to the characteristic in controlling the plant.

Psychological Need Satisfaction and Achievement Goals: Exploring Indirect Effects of Academic and Social Adaptation Following the Transition to Secondary School

ERIC Educational Resources Information Center

Duchesne, Stéphane; Ratelle, Catherine F.; Feng, Bei

2017-01-01

There is abundant evidence to suggest that students' achievement goals (AGs) predict their motivation and performance. While it has been proposed that psychological need satisfaction (PNS) may affect AG, empirical support remains limited during the transition to secondary school. This prospective study addresses this gap by examining the link…

Tools for Management for Grassland Ecosystem Sustainability: Thinking "Outside the Box"

Treesearch

Gerald J. Gottfried

2004-01-01

Grassland ecosystem management is dynamic and has adapted to the development of new tools and ideas. Our ancestors were indirectly managing grasslands when they learned to move livestock to take advantage of better water and greener forage. One could argue that even their hunting of grassland wildlife, especially the use of fire to drive animals to waiting hunters, had...

Climate change and water scarcity effects on the rural income distribution in the Mediterranean

NASA Astrophysics Data System (ADS)

Quiroga, Sonia; Suárez, Cristina

2015-04-01

This paper examines the effects of climate change and water scarcity on the agricultural outputs in the Mediterranean region. By now the effects of water scarcity as a response to climate change or policy restrictions has been analyzed with response functions considering the direct effects on crop productivity. Here we consider a complementary indirect effect on social distribution of incomes which is essential in the long term. We estimate crop production functions for a range of Mediterranean crops in Spain and we use a decomposition of the Gini coefficient to estimate the impact of climate change and water scarcity on yield disparities. This social aspect is important for climate change policies since it can be determinant for the public acceptation of certain adaptation measures in a context of water scarcity. We provide the empirical estimations for the marginal effects on the two considered direct and indirect impacts. In our estimates we consider both bio-physical and socio-economic aspects to conclude that there are long term implications on both competitiveness and social disparities. We find disparities in the adaptation strategies depending on the crop and the region analyzed.

Transcriptome analysis of the Dickeya dadantii PecS regulon during the early stages of interaction with Arabidopsis thaliana.

PubMed

Pédron, Jacques; Chapelle, Emilie; Alunni, Benoît; Van Gijsegem, Frédérique

2018-03-01

PecS is one of the major global regulators controlling the virulence of Dickeya dadantii, a broad-host-range phytopathogenic bacterium causing soft rot on several plant families. To define the PecS regulon during plant colonization, we analysed the global transcriptome profiles in wild-type and pecS mutant strains during the early colonization of the leaf surfaces and in leaf tissue just before the onset of symptoms, and found that the PecS regulon consists of more than 600 genes. About one-half of these genes are down-regulated in the pecS mutant; therefore, PecS has both positive and negative regulatory roles that may be direct or indirect. Indeed, PecS also controls the regulation of a few dozen regulatory genes, demonstrating that this global regulator is at or near the top of a major regulatory cascade governing adaptation to growth in planta. Notably, PecS acts mainly at the very beginning of infection, not only to prevent virulence gene induction, but also playing an active role in the adaptation of the bacterium to the epiphytic habitat. Comparison of the patterns of gene expression inside leaf tissues and during early colonization of leaf surfaces in the wild-type bacterium revealed 637 genes modulated between these two environments. More than 40% of these modulated genes are part of the PecS regulon, emphasizing the prominent role of PecS during plant colonization. © 2017 BSPP AND JOHN WILEY & SONS LTD.

Conversing across cultures: East-West communication styles in work and nonwork contexts.

PubMed

Sanchez-Burks, Jeffrey; Lee, Fiona; Choi, Incheol; Nisbett, Richard; Zhao, Shuming; Koo, Jasook

2003-08-01

Four experiments provided evidence that East-West differences in attention to indirect meaning are more pronounced in work settings compared with nonwork settings as suggested by prior research on Protestant relational ideology. Study 1 compared errors in interpreting indirect messages in work and nonwork contexts across three cultures. Studies 2 and 3 examined differences in self-reported indirectness with coworkers versus nonwork acquaintances across three cultures controlling for variation in individualism--collectivism. Study 4 examined self-reported indirectness in bicultural managers and experimentally manipulated the salience of Western versus Eastern culture. The results showed that Americans, but not East Asians, were less attentive to indirect cues in work than nonwork settings and that East-West differences in indirectness were greater in work than nonwork settings.

INDIRECT INTELLIGENT SLIDING MODE CONTROL OF A SHAPE MEMORY ALLOY ACTUATED FLEXIBLE BEAM USING HYSTERETIC RECURRENT NEURAL NETWORKS.

PubMed

Hannen, Jennifer C; Crews, John H; Buckner, Gregory D

2012-08-01

This paper introduces an indirect intelligent sliding mode controller (IISMC) for shape memory alloy (SMA) actuators, specifically a flexible beam deflected by a single offset SMA tendon. The controller manipulates applied voltage, which alters SMA tendon temperature to track reference bending angles. A hysteretic recurrent neural network (HRNN) captures the nonlinear, hysteretic relationship between SMA temperature and bending angle. The variable structure control strategy provides robustness to model uncertainties and parameter variations, while effectively compensating for system nonlinearities, achieving superior tracking compared to an optimized PI controller.

Adaptive Controller Effects on Pilot Behavior

NASA Technical Reports Server (NTRS)

Trujillo, Anna C.; Gregory, Irene M.; Hempley, Lucas E.

2014-01-01

Adaptive control provides robustness and resilience for highly uncertain, and potentially unpredictable, flight dynamics characteristic. Some of the recent flight experiences of pilot-in-the-loop with an adaptive controller have exhibited unpredicted interactions. In retrospect, this is not surprising once it is realized that there are now two adaptive controllers interacting, the software adaptive control system and the pilot. An experiment was conducted to categorize these interactions on the pilot with an adaptive controller during control surface failures. One of the objectives of this experiment was to determine how the adaptation time of the controller affects pilots. The pitch and roll errors, and stick input increased for increasing adaptation time and during the segment when the adaptive controller was adapting. Not surprisingly, altitude, cross track and angle deviations, and vertical velocity also increase during the failure and then slowly return to pre-failure levels. Subjects may change their behavior even as an adaptive controller is adapting with additional stick inputs. Therefore, the adaptive controller should adapt as fast as possible to minimize flight track errors. This will minimize undesirable interactions between the pilot and the adaptive controller and maintain maneuvering precision.

New Horizons in the Development of Novel Needle-Free Immunization Strategies to Increase Vaccination Efficacy.

PubMed

Schulze, Kai; Ebensen, Thomas; Riese, Peggy; Prochnow, Blair; Lehr, Claus-Michael; Guzmán, Carlos A

2016-01-01

The young twenty-first century has already brought several medical advances, such as a functional artificial human liver created from stem cells, improved antiviral (e.g., against HIV) and cancer (e.g., against breast cancer) therapies, interventions controlling cardiovascular diseases, and development of new and optimized vaccines (e.g., HPV vaccine). However, despite this substantial progress and the achievements of the last century, humans still suffer considerably from diseases, especially from infectious diseases. Thus, almost one-fourth of all deaths worldwide are caused directly or indirectly by infectious agents. Although vaccination has led to the control of many diseases, including smallpox, diphtheria, and tetanus, emerging diseases are still not completely contained. Furthermore, pathogens such as Bordetella pertussis undergo alterations making adaptation of the respective vaccine necessary. Moreover, insufficient implementation of vaccination campaigns leads to re-emergence of diseases which were believed to be already under control (e.g., poliomyelitis). Therefore, novel vaccination strategies need to be developed in order to meet the current challenges including lack of compliance, safety issues, and logistic constraints. In this context, mucosal and transdermal approaches constitute promising noninvasive vaccination strategies able to match these demands.

Two SHIPs passing in the middle of the immune system.

PubMed

Corey, Seth J; Mehta, Hrishikesh M; Stein, Paul L

2012-07-01

Immunity requires a complex, multiscale system of molecules, cells, and cytokines. In this issue of the European Journal of Immunology, Collazo et al. [Eur. J. Immunol. 2012. 42: 1785-1796] provide evidence that links the lipid phosphatase SHIP1 with the coordination of interactions between regulatory T (Treg) cells and myeloid-derived suppressor cells (MDSCs). Using conditional knockouts of SHIP1 in either the myeloid or T-cell-lineage of mice, the authors show that the regulated development of Treg cells is controlled directly by cell-intrinsic SHIP1, and indirectly by extrinsic SHIP1 control of an unknown myeloid cell. Regulation of MDSCs is also determined by SHIP1 in an extrinsic manner, again via an as-yet-unknown myeloid cell. Furthermore, this extrinsic control of Treg cells and MDSCs is mediated in part by increased production of G-CSF, a growth factor critical for the production of neutrophils, in SHIP1-deficient mice. Thus, a physiologically important implication of this report is the collaboration between the innate and adaptive immune systems in fine tuning of Treg cells as discussed in this commentary. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Arbovirus models to provide practical management tools for mosquito control and disease prevention in the Northern Territory, Australia.

PubMed

Jacups, Susan P; Whelan, Peter I; Harley, David

2011-03-01

Ross River virus (RRV) causes the most common human arbovirus disease in Australia. Although the disease is nonfatal, the associated arthritis and postinfection fatigue can be debilitating for many months, impacting on workforce participation. We sought to create an early-warning system to notify of approaching RRV disease outbreak conditions for major townships in the Northern Territory. By applying a logistic regression model to meteorologic factors, including rainfall, a postestimation analysis of sensitivity and specificity can create rainfall cut-points. These rainfall cut-points indicate the rainfall level above which previous epidemic conditions have occurred. Furthermore, rainfall cut-points indirectly adjust for vertebrate host data from the agile wallaby (Macropus agilis) as the life cycle of the agile wallaby is intricately meshed with the wet season. Once generated, cut-points can thus be used prospectively to allow timely implementation of larval survey and control measures and public health warnings to preemptively reduce RRV disease incidence. Cut-points are location specific and have the capacity to replace previously used models, which require data management and input, and rarely provide timely notification for vector control requirements and public health warnings. These methods can be adapted for use elsewhere.

Induction of innate immunity in control of mucosal transmission of HIV.

PubMed

Wang, Yufei; Lehner, Thomas

2011-09-01

To present evidence of the role of innate mucosal immunity and to harness this arm of immunity in protection against HIV infection. Dendritic cells, monocytes, natural killer (NK) cells and γδ T cells are critical in innate immunity, which is mediated by Toll-like receptor (TLR) and recently identified stress pathways. Complement factors, cytokines and chemokines have diverse functions usually affecting HIV infection indirectly. A novel group of innate intracellular HIV restriction factors has been identified - APOBEC3G, TRIM5α and tetherin - all of which are upregulated by type I interferons and some by vaccination and TLR agonists. Whereas innate immunity conventionally lacks memory, recent evidence suggests that some of the cells and intracellular factors may express immunological memory-like features. Innate mucosal immunity may provide early effective control of HIV transmission and replication. Some vaccines can enhance innate immune factors, such as APOBEC3G and control HIV during the eclipse period, allowing full weight of neutralizing and/or cytotoxic T cells to develop and prevent mucosal HIV infection. The next generation of vaccines should be designed to target both innate and adaptive immune memory responses.

Trait attentional control influences the relationship between repetitive negative thinking and psychopathology symptoms.

PubMed

Mills, Adam C; Grant, DeMond M; Judah, Matt R; White, Evan J; Taylor, Danielle L; Frosio, Kristen E

2016-04-30

Repetitive negative thinking (RNT) has been implicated in several disorders (e.g., Clark (2005)). However, little research has examined how RNT influences other risk factors of psychopathology, such as attentional control. This study used prospective methodology to determine if relationships among various RNT styles and symptoms of psychological disorders are indirectly influenced by facets of attentional control. The sample included 376 participants who completed measures of RNT (worry, rumination, anticipatory processing, obsessions, intrusive thoughts and panic cognitions), psychopathology (generalized anxiety disorder, depression, social anxiety, obsessive-compulsive disorder, posttraumatic stress disorder, and panic disorder), and attentional control at two time points. Several relationships between RNT forms and symptom levels were indirectly predicted by the focusing subscale of attentional control; however, the patterns of these relationships differed based on the disorder. The shifting subscale did not indirectly predict any relationship. Therefore, it appears that low focusing may be a particular risk factor for the development of later RNT and/or psychopathology symptoms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Longitudinal predictors of school-age academic achievement: unique contributions of toddler-age aggression, oppositionality, inattention, and hyperactivity.

PubMed

Brennan, Lauretta M; Shaw, Daniel S; Dishion, Thomas J; Wilson, Melvin

2012-11-01

This project examined the unique predictive validity of parent ratings of toddler-age aggression, oppositionality, inattention, and hyperactivity-impulsivity to academic achievement at school-age in a sample of 566 high-risk children and families. The study also investigated potential indirect effects of the Family Check-Up on school-age academic achievement through changes in child behavior problems. The results demonstrated that toddler-age aggression was most consistently associated with school-age academic achievement, albeit modestly. Moreover, findings showed that the intervention predicted greater decreases in aggression from ages 2-3 to 4-5 compared to controls. The results suggest that in high-risk toddler-aged children, aggression may be a more consistent predictor of school-age academic achievement than other externalizing dimensions, which has implications for early identification and efforts to promote children's adaptation.

Society, sex, and STIs: human behavior and the evolution of sexually transmitted diseases and their agents.

PubMed

Nahmias, Susa Beckman; Nahmias, Daniella

2011-08-01

The last few decades have provided new perspectives on the increasingly complex interrelationships between the evolutionary epidemiology of STDs and their agents, human sexuality, and economic, social, cultural, and technological developments. Rapidly emerging HIV/AIDS, globalization, migration, and information technology are some factors that stress the importance of focusing on how old and new sexually transmitted infections (STIs) are spread, both in and between networks and populations. This review of determinants of STI transmission emphasizes their impact on disease prevalence and transmission, as well as their potential for affecting the agents themselves--directly or indirectly. Interventions aiming to control the spread of STIs and HIV on the different levels of society need to be adapted to the specific environment and need to integrate social structures, such as economic and gender inequality and mobility, as well as the great variability and complexity of sexual behavior. © 2011 New York Academy of Sciences.

Functional Association between Regulatory RNAs and the Annexins

PubMed Central

Monastyrskaya, Katia

2018-01-01

Cells respond to pathophysiological states by activation of stress-induced signalling. Regulatory non-coding microRNAs (miRNAs) often form stable feed-forward loops which ensure prolongation of the signal, contributing to sustained activation. Members of the annexin protein family act as sensors for Ca2+, pH, and lipid second messengers, and regulate various signalling pathways. Recently, annexins were reported to participate in feedback loops, suppressing miRNA synthesis and attenuating stress-induced dysregulation of gene expression. They can directly or indirectly associate with RNAs, and are transferred between the cells in exosomes and shed microvesicles. The ability of annexins to recruit other proteins and miRNAs into exosomes implicates them in control of cell–cell interactions, affecting the adaptive responses and remodelling processes during disease. The studies summarized in this Review point to an emerging role of annexins in influencing the synthesis, localisation, and transfer of regulatory RNAs. PMID:29462943

[Analysis of the publicity campaign of the tobacco brand Fortuna in 1999-2000].

PubMed

Sarría-Santamera, A; Cortés-Blanco, M; Elder, J

2001-01-01

The majority of tobacco advertisement in Spain is directed at youth. This advertisement, carried out on several fronts, is particularly effective with young people. In the present work we analyze different advertising efforts involved in the ad campaign carried out by Fortuna-brand (a product of the company Tabacalera S.A., and sector leader of sales in Spain) in 1999 and 2000. In terms of their marketing strategy, we can conclude that Fortuna's principal commercial objective is presenting tobacco as intrinsically associated with being young. Both the indirect promotion of its products through activities and its commercials, are aimed towards developing the image that tobacco symbolizes the series of core values more appreciated by youth. Relevant legislation will have to be adapted to this reality in order to control specifically the manner in which publicity such as that promoted by Fortuna is directed to the population.

Acoustooptic linear algebra processors - Architectures, algorithms, and applications

NASA Technical Reports Server (NTRS)

Casasent, D.

1984-01-01

Architectures, algorithms, and applications for systolic processors are described with attention to the realization of parallel algorithms on various optical systolic array processors. Systolic processors for matrices with special structure and matrices of general structure, and the realization of matrix-vector, matrix-matrix, and triple-matrix products and such architectures are described. Parallel algorithms for direct and indirect solutions to systems of linear algebraic equations and their implementation on optical systolic processors are detailed with attention to the pipelining and flow of data and operations. Parallel algorithms and their optical realization for LU and QR matrix decomposition are specifically detailed. These represent the fundamental operations necessary in the implementation of least squares, eigenvalue, and SVD solutions. Specific applications (e.g., the solution of partial differential equations, adaptive noise cancellation, and optimal control) are described to typify the use of matrix processors in modern advanced signal processing.

A versatile indirect detector design for hard X-ray microimaging

NASA Astrophysics Data System (ADS)

Douissard, P.-A.; Cecilia, A.; Rochet, X.; Chapel, X.; Martin, T.; van de Kamp, T.; Helfen, L.; Baumbach, T.; Luquot, L.; Xiao, X.; Meinhardt, J.; Rack, A.

2012-09-01

Indirect X-ray detectors are of outstanding importance for high resolution imaging, especially at synchrotron light sources: while consisting mostly of components which are widely commercially available, they allow for a broad range of applications in terms of the X-ray energy employed, radiation dose to the detector, data acquisition rate and spatial resolving power. Frequently, an indirect detector consists of a thin-film single crystal scintillator and a high-resolution visible light microscope as well as a camera. In this article, a novel modular-based indirect design is introduced, which offers several advantages: it can be adapted for different cameras, i.e. different sensor sizes, and can be trimmed to work either with (quasi-)monochromatic illumination and the correspondingly lower absorbed dose or with intense white beam irradiation. In addition, it allows for a motorized quick exchange between different magnifications / spatial resolutions. Developed within the European project SCINTAX, it is now commercially available. The characteristics of the detector in its different configurations (i.e. for low dose or for high dose irradiation) as measured within the SCINTAX project will be outlined. Together with selected applications from materials research, non-destructive evaluation and life sciences they underline the potential of this design to make high resolution X-ray imaging widely available.

Influence of the indirect effects of guppies on life-history evolution in Rivulus hartii.

PubMed

Walsh, Matthew R; Reznick, David N

2010-06-01

Early theories of life-history evolution predict that increased predation on young/small individuals selects for delayed maturation and decreased reproductive effort, but such theory only considers changes in mortality. Predators reduce prey abundance and increase food to survivors. Theory that incorporates such indirect effects yields different predictions. Trinidadian killifish, Rivulus hartii, inhabit communities with and without guppies. Guppies prey on young Rivulus and Rivulus densities decline and growth rates increase when guppies are present. Prior work showed that Rivulus phenotypes from communities with guppies matured earlier and had higher fecundity, consistent with theories that incorporate indirect effects. Here we examined the genetic basis of these differences by rearing 2nd generation, laboratory-born Rivulus from sites with and without guppies under two food levels that match natural differences in growth. Many locality x food interactions were significant, often reversing the relationship between communities. Such interactions imply that there are fitness trade-offs associated with adaptation to high or low resource environments. On high food, Rivulus from localities with guppies matured earlier, produced many small eggs, and exhibited increased reproductive investment; these differences reversed on low food. Our results suggest that indirect effects mold Rivulus evolution and thereby highlight connections between community processes and evolutionary change.

A Conceptual Framework for Planning Systemic Human Adaptation to Global Warming

PubMed Central

Tait, Peter W.; Hanna, Elizabeth G.

2015-01-01

Human activity is having multiple, inter-related effects on ecosystems. Greenhouse gas emissions persisting along current trajectories threaten to significantly alter human society. At 0.85 °C of anthropogenic warming, deleterious human impacts are acutely evident. Additional warming of 0.5 °C–1.0 °C from already emitted CO2 will further intensify extreme heat and damaging storm events. Failing to sufficiently address this trend will have a heavy human toll directly and indirectly on health. Along with mitigation efforts, societal adaptation to a warmer world is imperative. Adaptation efforts need to be significantly upscaled to prepare society to lessen the public health effects of rising temperatures. Modifying societal behaviour is inherently complex and presents a major policy challenge. We propose a social systems framework for conceptualizing adaptation that maps out three domains within the adaptation policy landscape: acclimatisation, behavioural adaptation and technological adaptation, which operate at societal and personal levels. We propose that overlaying this framework on a systems approach to societal change planning methods will enhance governments’ capacity and efficacy in strategic planning for adaptation. This conceptual framework provides a policy oriented planning assessment tool that will help planners match interventions to the behaviours being targeted for change. We provide illustrative examples to demonstrate the framework’s application as a planning tool. PMID:26334285

A Conceptual Framework for Planning Systemic Human Adaptation to Global Warming.

PubMed

Tait, Peter W; Hanna, Elizabeth G

2015-08-31

Human activity is having multiple, inter-related effects on ecosystems. Greenhouse gas emissions persisting along current trajectories threaten to significantly alter human society. At 0.85 °C of anthropogenic warming, deleterious human impacts are acutely evident. Additional warming of 0.5 °C-1.0 °C from already emitted CO₂ will further intensify extreme heat and damaging storm events. Failing to sufficiently address this trend will have a heavy human toll directly and indirectly on health. Along with mitigation efforts, societal adaptation to a warmer world is imperative. Adaptation efforts need to be significantly upscaled to prepare society to lessen the public health effects of rising temperatures. Modifying societal behaviour is inherently complex and presents a major policy challenge. We propose a social systems framework for conceptualizing adaptation that maps out three domains within the adaptation policy landscape: acclimatisation, behavioural adaptation and technological adaptation, which operate at societal and personal levels. We propose that overlaying this framework on a systems approach to societal change planning methods will enhance governments' capacity and efficacy in strategic planning for adaptation. This conceptual framework provides a policy oriented planning assessment tool that will help planners match interventions to the behaviours being targeted for change. We provide illustrative examples to demonstrate the framework's application as a planning tool.

Why CMV is a candidate for elimination and then eradication.

PubMed

Griffiths, Paul D; Mahungu, Tabitha

2016-07-01

Cytomegalovirus (CMV) is well-known for the end organ diseases (EODs) it causes following viraemic dissemination in immunocompromised hosts. These are termed the direct effects of CMV, where a diagnosis can be made in an individual patient. In addition, CMV is associated with indirect effects where populations can be seen to be disadvantaged compared to those without CMV. These indirect effects have been described in solid organ transplants, bone marrow transplants, advanced HIV, people admitted to intensive care units, the elderly and the general population. We summarise the evidence that associates CMV with its direct effects following congenital infection, solid organ transplantation, bone marrow transplantation and advanced HIV as well as its indirect effects in all patient populations. We propose that the greatest worldwide burden of CMV comes from its indirect effects. Control of this infection at the population level is being sought through the development of vaccines to control EODs where cost effectiveness is expected. We propose that the financial case for universal immunisation will be enhanced even further by the potential benefits vaccines may produce against the indirect effects of CMV.

Indirect costs and workplace productivity loss associated with non-Hodgkin lymphoma.

PubMed

Yu, Justin S; Hansen, Ryan N; Valderrama, Adriana; Carlson, Josh J

2016-11-01

The objective of this study was to examine indirect costs and workplace productivity loss (defined as an aggregate measure of absenteeism, short-term disability, and long-term disability days) associated with non-Hodgkin lymphoma (NHL) from a societal perspective in a commercially insured working-age United States population. The MarketScan(®) Commercial Claims and Encounters and Health and Productivity Management Databases (2007-2013) were used in this study, with controls matched 3:1 to NHL patients. In comparison to controls, NHL patients incurred significantly more workplace productivity loss (31.99 days; 95% CI: 25.24 days, 38.73 days; p < 0.001) and associated indirect costs ($6302.34; 95% CI: $4973.40, $7631.28; p < 0.001) in the 12-month post-diagnosis period when adjusting for covariates. NHL contributes significantly to losses in workplace productivity and higher associated indirect costs.

Large and abundant flowers increase indirect costs of corollas: a study of coflowering sympatric Mediterranean species of contrasting flower size.

PubMed

Teixido, Alberto L; Valladares, Fernando

2013-09-01

Large floral displays receive more pollinator visits but involve higher production and maintenance costs. This can result in indirect costs which may negatively affect functions like reproductive output. In this study, we explored the relationship between floral display and indirect costs in two pairs of coflowering sympatric Mediterranean Cistus of contrasting flower size. We hypothesized that: (1) corolla production entails direct costs in dry mass, N and P, (2) corollas entail significant indirect costs in terms of fruit set and seed production, (3) indirect costs increase with floral display, (4) indirect costs are greater in larger-flowered sympatric species, and (5) local climatic conditions influence indirect costs. We compared fruit set and seed production of petal-removed flowers and unmanipulated control flowers and evaluated the influence of mean flower number and mean flower size on relative fruit and seed gain of petal-removed and control flowers. Fruit set and seed production were significantly higher in petal-removed flowers in all the studied species. A positive relationship was found between relative fruit gain and mean individual flower size within species. In one pair of species, fruit gain was higher in the large-flowered species, as was the correlation between fruit gain and mean number of open flowers. In the other pair, the correlation between fruit gain and mean flower size was also higher in the large-flowered species. These results reveal that Mediterranean environments impose significant constraints on floral display, counteracting advantages of large flowers from the pollination point of view with increased indirect costs of such flowers.

Indirect effects of phorid fly parasitoids on the mechanisms of interspecific competition among ants.

PubMed

Morrison, Lloyd W

1999-10-01

Indirect effects, which occur when the impact of one species upon another requires the existence of an intermediary species, are apparently very common and may be of greater magnitude than direct effects. Behaviorally mediated indirect effects occur when one species affects the behavior of a second, which in turn affects how that species interacts with a third. I studied behaviorally mediated indirect effects on the mechanisms of competition in two congeneric fire ant species in the presence and absence of parasitoid phorid flies, which parasitized only one ant species. In observational and experimental field studies, the presence of native Texas phorid flies in the genus Pseudacteon decreased food retrieval by their host, Solenopsis geminata (F.), by as much as 50%. In the presence of phorid flies, many S. geminata workers assumed a stationary, curled defensive posture and did not forage. Although the phorid parasitoids had a relatively large effect on exploitative competition, there was no measurable effect on interference competition. Fierce interspecific aggression was observed between S. geminata and S. invicta Buren, and the presence of phorids had no effect on the outcome of these contests. The indirect effects of Pseudacteon parasitoids on Solenopsis fire ant resource retrieval appear to be larger than the direct effect of mortality. Some aspects of the foraging behavior of these Solenopsis species may be, in part, evolutionary adaptations to phorid parasitoid pressure. Because of the relatively large indirect effects, South American Pseudacteon phorids may be promising biocontrol agents of imported fire ants, S. invicta, in the USA. In a laboratory study, a single South American Pseudacteon female was able to significantly decrease food retrieval rates of a North American population of the imported fire ant, S. invicta.

[Regulation of Positive and Negative Emotions as Mediator between Maternal Emotion Socialization and Child Problem Behavior].

PubMed

Fäsche, Anika; Gunzenhauser, Catherine; Friedlmeier, Wolfgang; von Suchodoletz, Antje

2015-01-01

The present study investigated five to six year old children's ability to regulate negative and positive emotions in relation to psychosocial problem behavior (N=53). It was explored, whether mothers' supportive and nonsupportive strategies of emotion socialization influence children's problem behavior by shaping their emotion regulation ability. Mothers reported on children's emotion regulation and internalizing and externalizing problem behavior via questionnaire, and were interviewed about their preferences for socialization strategies in response to children's expression of negative affect. Results showed that children with more adaptive expression of adequate positive emotions had less internalizing behavior problems. When children showed more control of inadequate negative emotions, children were less internalizing as well as externalizing in their behavior. Furthermore, results indicated indirect relations of mothers' socialization strategies with children's problem behavior. Control of inadequate negative emotions mediated the link between non-supportive strategies on externalizing problem behavior. Results suggest that emotion regulatory processes should be part of interventions to reduce the development of problematic behavior in young children. Parents should be trained in dealing with children's emotions in a constructive way.

Approach to in-process tool wear monitoring in drilling: Application of Kalman filter theory

NASA Astrophysics Data System (ADS)

He, Ning; Zhang, Youzhen; Pan, Liangxian

1993-05-01

The two parameters often used in adaptive control, tool wear and wear rate, are the important factors affecting machinability. In this paper, it is attempted to use the modern cybernetics to solve the in-process tool wear monitoring problem by applying the Kalman filter theory to monitor drill wear quantitatively. Based on the experimental results, a dynamic model, a measuring model and a measurement conversion model suitable for Kalman filter are established. It is proved that the monitoring system possesses complete observability but does not possess complete controllability. A discriminant for selecting the characteristic parameters is put forward. The thrust force Fz is selected as the characteristic parameter in monitoring the tool wear by this discriminant. The in-process Kalman filter drill wear monitoring system composed of force sensor microphotography and microcomputer is well established. The results obtained by the Kalman filter, the common indirect measuring method and the real drill wear measured by the aid of microphotography are compared. The result shows that the Kalman filter has high precision of measurement and the real time requirement can be satisfied.

The plant cytoskeleton controls regulatory volume increase.

PubMed

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

2013-09-01

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

Ovarian control and monitoring in amphibians.

PubMed

Calatayud, N E; Stoops, M; Durrant, B S

2018-03-15

Amphibian evolution spans over 350 million years, consequently this taxonomic group displays a wide, complex array of physiological adaptations and their diverse modes of reproduction are a prime example. Reproduction can be affected by taxonomy, geographic and altitudinal distribution, and environmental factors. With some exceptions, amphibians can be categorized into discontinuous (strictly seasonal) and continuous breeders. Temperature and its close association with other proximate and genetic factors control reproduction via a tight relationship with circadian rhythms which drive genetic and hormonal responses to the environment. In recent times, the relationship of proximate factors and reproduction has directly or indirectly lead to the decline of this taxonomic group. Conservationists are tackling the rapid loss of species through a wide range of approaches including captive rescue. However, there is still much to be learned about the mechanisms of reproductive control and its requirements in order to fabricate species-appropriate captive environments that address a variety of reproductive strategies. As with other taxonomic groups, assisted reproductive technologies and other reproductive monitoring tools such as ultrasound, hormone analysis and body condition indices can assist conservationists in optimizing captive husbandry and breeding. In this review we discuss some of the mechanisms of ovarian control and the different tools being used to monitor female reproduction. Copyright © 2018 Elsevier Inc. All rights reserved.

Predicting life-history adaptations to pollutants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maltby, L.

1995-12-31

Animals may adapt to pollutant stress so that individuals from polluted environments are less susceptible than those from unpolluted environments. In addition to such direct adaptations, animals may respond to pollutant stress by life-history modifications; so-called indirect adaptations. This paper will demonstrate how, by combining life-history theory and toxicological data, it is possible to predict stress-induced alterations in reproductive output and offspring size. Pollutant-induced alterations in age-specific survival in favor of adults and reductions in juvenile growth, conditions are predicted to select for reduced investment in reproduction and the allocation of this investment into fewer, larger offspring. Field observations onmore » the freshwater crustaceans, Asellus aquaticus and Gammarus pulex, support these predictions. Females from metal-polluted sites had lower investment in reproduction and produced larger offspring than females of the same species from unpolluted sites. Moreover, interpopulation differences in reproductive biology persisted in laboratory cultures indicating that they had a genetic basis and were therefore due to adaptation rather than acclimation. The general applicability of this approach will be considered.« less

Learning-by-catching: uncertain invasive-species populations and the value of information.

PubMed

D'Evelyn, Sean T; Tarui, Nori; Burnett, Kimberly; Roumasset, James A

2008-12-01

This paper develops a model of invasive species control when the species' population size is unknown. In the face of an uncertain population size, a resource manager's species-control efforts provide two potential benefits: (1) a direct benefit of possibly reducing the population of invasive species, and (2) an indirect benefit of information acquisition (due to learning about the population size, which reduces uncertainty). We provide a methodology that takes into account both of these benefits, and show how optimal management decisions are altered in the presence of the indirect benefit of learning. We then apply this methodology to the case of controlling the Brown Treesnake (Boiga irregularis) on the island of Saipan. We find that the indirect benefit--the value of information to reduce uncertainty--is likely to be quite large.

Executive Function and Internalizing Symptoms in Adolescents and Young Adults With Congenital Heart Disease: The Role of Coping.

PubMed

Jackson, Jamie L; Gerardo, Gina M; Monti, Jennifer D; Schofield, Kyle A; Vannatta, Kathryn

2018-01-10

Executive functioning deficits have been documented among congenital heart disease (CHD) survivors and may contribute to emotional distress. Little research has investigated the role of coping in this association. This study examined the role of coping in accounting for the association between self-reported executive function problems and internalizing symptoms among adolescents and emerging adults (AEAs), as well as young adults (YAs) with CHD. Participants included 74 AEA ( M age  = 19.32  ±  3.47 years, range 15-25 years) and 98 YA CHD survivors ( M age  = 32.00  ±  3.69 years, range 26-39 years), recruited from pediatric and adult outpatient cardiology clinics. Participants completed self-report measures of executive function problems, coping (primary control, secondary control, and disengagement coping), and internalizing symptoms. Lesion severity classification and functional impairment due to symptoms of heart failure were determined from medical chart review. Significant problems in executive function were reported by 5% of AEA and 13% of YA. Coping was not associated with executive function problems or internalizing symptoms for AEA. However, among YA, less use of adaptive coping strategies and more maladaptive coping responses was associated with both more executive function problems and internalizing symptoms. An indirect effect of executive function problems on internalizing symptoms via secondary control coping emerged for YA. Executive function problems may disrupt the ability to use important adaptive coping skills, such as cognitive reappraisal, positive thinking, and acceptance, thereby resulting in greater emotional distress among YA CHD survivors. © The Author(s) 2018. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Robust Optimal Adaptive Control Method with Large Adaptive Gain

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2009-01-01

In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly. However, a large adaptive gain can lead to high-frequency oscillations which can adversely affect robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient stability robustness. Simulations were conducted for a damaged generic transport aircraft with both standard adaptive control and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model while maintaining a sufficient time delay margin.

A simple method to prevent hard X-ray-induced preheating effects inside the cone tip in indirect-drive fast ignition implosions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Dongxiao; Shan, Lianqiang; Zhou, Weimin

During fast-ignition implosions, preheating of inside the cone tip caused by hard X-rays can strongly affect the generation and transport of hot electrons in the cone. Although indirect-drive implosions have a higher implosion symmetry, they cause stronger preheating effects than direct-drive implosions. To control the preheating of the cone tip, we propose the use of indirect-drive fast-ignition targets with thicker tips. Experiments carried out at the ShenGuang-III prototype laser facility confirmed that thicker tips are effective for controlling preheating. Moreover, these results were consistent with those of 1D radiation hydrodynamic simulations.

Modelling of piezoelectric actuator dynamics for active structural control

NASA Technical Reports Server (NTRS)

Hagood, Nesbitt W.; Chung, Walter H.; Von Flotow, Andreas

1990-01-01

The paper models the effects of dynamic coupling between a structure and an electrical network through the piezoelectric effect. The coupled equations of motion of an arbitrary elastic structure with piezoelectric elements and passive electronics are derived. State space models are developed for three important cases: direct voltage driven electrodes, direct charge driven electrodes, and an indirect drive case where the piezoelectric electrodes are connected to an arbitrary electrical circuit with embedded voltage and current sources. The equations are applied to the case of a cantilevered beam with surface mounted piezoceramics and indirect voltage and current drive. The theoretical derivations are validated experimentally on an actively controlled cantilevered beam test article with indirect voltage drive.

Psychosocial Adaptation to Disability Within the Context of Positive Psychology: Philosophical Aspects and Historical Roots.

PubMed

Livneh, Hanoch; Martz, Erin

2016-03-01

The purpose of this article is to review the conceptual and clinical similarities that exist between the principles of positive psychology and those underlying rehabilitation counseling and psychology, occupational rehabilitation, and those espoused by the field of psychosocial adaptation to chronic illness and disability (CID). Three themes were selected for review. These included the historical contributions of early scholars in the area of psychosocial adaptation to CID that later were indirectly infused into mainstream positive psychology; state and trait constructs that constitute much of the infrastructure of positive psychology and psychosocial adaptation to CID; and, finally, the philosophical congruencies between positive psychology and psychosocial adaptation to CID. The existing literature indicates that there is a substantial philosophical and conceptual overlap between the fields of positive psychology and psychosocial adaptation to CID. Since theoreticians and researchers, from both fields, often use differing terminology and definitions to describe similar concepts, as well as seek similar research goals, it would behoove both fields to seek a closer partnership in order to establish a meaningful dialogue that focuses on human strengths and virtues in the lives of people with CID.

Inspecting the Dangers of Feeling like a Fake: An Empirical Investigation of the Impostor Phenomenon in the World of Work

PubMed Central

Neureiter, Mirjam; Traut-Mattausch, Eva

2016-01-01

To investigate the link between the impostor phenomenon (IP), career self-management (CSM) factors, and work-relevant outcomes, we looked at the IP's impact on career optimism, career adaptability, and knowledge of the job market, as well as on employee- and organizationally-relevant outcomes. We analyzed data from 238 working professionals (57% female) using parallel multiple mediation analyses. The results revealed that the IP was negatively related to all work-relevant outcomes through decreased CSM factors, which were subsequently associated with the outcomes. As hypothesized, employee-relevant subjective outcomes were mediated by optimism and employee-relevant objective (i.e., economic) outcomes by adaptability and knowledge. Additional mediating effects occurred. Regarding organizationally relevant outcomes, adaptability mediated the IP's impact on organizational citizenship behavior. The IP was only indirectly related to continuance commitment through adaptability and to affective commitment through optimism. We discuss the theoretical and practical implications and offer ideas for future research. PMID:27729882

Effects of Internet-Based Self-Efficacy Intervention on Secondary Traumatic Stress and Secondary Posttraumatic Growth among Health and Human Services Professionals Exposed to Indirect Trauma

PubMed Central

Cieslak, Roman; Benight, Charles C.; Rogala, Anna; Smoktunowicz, Ewelina; Kowalska, Martyna; Zukowska, Katarzyna; Yeager, Carolyn; Luszczynska, Aleksandra

2016-01-01

Background: Although the evidence for the associations among self-efficacy, secondary traumatic stress (STS) and secondary posttraumatic growth (SPTG) is mounting, there is a lack of the experimental evidence for the influence of self-efficacy on positive and negative mental health outcomes among professionals indirectly exposed to trauma. Purpose: This study investigated the effects of an internet-based self-efficacy intervention (the experimental condition), compared to an education (the active control condition) on STS and SPTG among workers exposed to traumatic events indirectly, through their clients. We hypothesized that the group assignment (experimental vs. control) would affect STS and SPTG indirectly, with a mediating role of self-efficacy beliefs. Methods: Participants were 168 health and human services professionals (78% women), exposed indirectly to a traumatic event at work. They were randomly assigned to either a 4-session internet-based self-efficacy intervention (n = 87) or an education control group (n = 81) which received information about coping resources and consequences of stressors at work or at home. STS, SPTG, and self-efficacy were measured at the baseline (Time 1), 1-month follow-up (Time 2) and 2-month follow-up (Time 3). Results: Analysis of covariance showed that the group assignment had a significant effect on STS (Time 2) and self-efficacy (Time 2), with lower STS and higher self-efficacy reported by the self-efficacy intervention participants. Compared to the experimental group, the active control (education) group participants reported higher SPTG at Time 2. Mediation analyses indicated that the group assignment had indirect effects on STS and SPTG at Time 3. Workers who experienced increases in self-efficacy (Time 2) through the intervention were more likely to report lower STS and higher SPTG at Time 3. Conclusion: Elucidating the mediating processes that explain why an intervention for secondary trauma works is essential in order to develop more effective support systems that promote improved mental health outcomes among health and human services professionals. Prevention programs for workers exposed indirectly to traumatic events may target self-efficacy enhancement and education. PMID:27458407

Sensory-Motor Adaptation to Space Flight: Human Balance Control and Artificial Gravity

NASA Technical Reports Server (NTRS)

Paloski, William H.

2004-01-01

Gravity, which is sensed directly by the otolith organs and indirectly by proprioceptors and exteroceptors, provides the CNS a fundamental reference for estimating spatial orientation and coordinating movements in the terrestrial environment. The sustained absence of gravity during orbital space flight creates a unique environment that cannot be reproduced on Earth. Loss of this fundamental CNS reference upon insertion into orbit triggers neuro-adaptive processes that optimize performance for the microgravity environment, while its reintroduction upon return to Earth triggers neuro-adaptive processes that return performance to terrestrial norms. Five pioneering symposia on The Role of the Vestibular Organs in the Exploration of Space were convened between 1965 and 1970. These innovative meetings brought together the top physicians, physiologists, and engineers in the vestibular field to discuss and debate the challenges associated with human vestibular system adaptation to the then novel environment of space flight. These highly successful symposia addressed the perplexing problem of how to understand and ameliorate the adverse physiological effects on humans resulting from the reduction of gravitational stimulation of the vestibular receptors in space. The series resumed in 2002 with the Sixth Symposium, which focused on the microgravity environment as an essential tool for the study of fundamental vestibular functions. The three day meeting included presentations on historical perspectives, vestibular neurobiology, neurophysiology, neuroanatomy, neurotransmitter systems, theoretical considerations, spatial orientation, psychophysics, motor integration, adaptation, autonomic function, space motion sickness, clinical issues, countermeasures, and rehabilitation. Scientists and clinicians entered into lively exchanges on how to design and perform mutually productive research and countermeasure development projects in the future. The problems posed by long duration missions dominated these discussions and were driven by the paucity of data available. These issues along with more specific recommendations arising from the above discussions will be addressed an upcoming issue of the Journal of Vestibular Research.

Blood circulation under conditions of weightlessness

NASA Technical Reports Server (NTRS)

Kastyan, I. I.; Kopanev, V. I.

1980-01-01

Experimental materials and published data on the problem of blood circulation in man and animals under conditions of short and long term weightlessness are summarized. The data obtained allow the conclusion, that when humans spent 5 days in a weightless state their blood circulation was not essentially distributed. Some features of the functioning of the cardiovascular system are pointed out: delay of adaptation rate, increase in lability, etc. There is a discussion of the physiological mechanisms for the direct and indirect effect of weightlessness. The direct effect comprise the complex of reactions caused by the significant fall in hydrostatic pressure and the indirect embraces all the reactions arising in the organism resulting from disturbance of the systematic character of the analyzers that take part in the analysis of space realtions and the body's orientation in space.

Adaptive Controller Adaptation Time and Available Control Authority Effects on Piloting

NASA Technical Reports Server (NTRS)

Trujillo, Anna; Gregory, Irene

2013-01-01

Adaptive control is considered for highly uncertain, and potentially unpredictable, flight dynamics characteristic of adverse conditions. This experiment looked at how adaptive controller adaptation time to recover nominal aircraft dynamics affects pilots and how pilots want information about available control authority transmitted. Results indicate that an adaptive controller that takes three seconds to adapt helped pilots when looking at lateral and longitudinal errors. The controllability ratings improved with the adaptive controller, again the most for the three seconds adaptation time while workload decreased with the adaptive controller. The effects of the displays showing the percentage amount of available safe flight envelope used in the maneuver were dominated by the adaptation time. With the displays, the altitude error increased, controllability slightly decreased, and mental demand increased. Therefore, the displays did require some of the subjects resources but these negatives may be outweighed by pilots having more situation awareness of their aircraft.

The effect of parent and peer attachment on suicidality: the mediation effect of self-control and anomie.

PubMed

Heydari, Arash; Teymoori, Ali; Nasiri, Hedayat

2015-04-01

We explore the influence of psycho-social factors including the attachment to parent and peer, self-control, and anomie on suicidality. Research questionnaires were distributed among 336 students of Shahid Chamran University of Ahvaz in Iran. The results demonstrated that mother and peer attachments had an indirect effect on suicidality via self-control and anomie, and self-control had a direct effect on suicidality and an indirect effect via anomie. Self-control and anomie had the most efficient role in the model with a large effect size. Findings are discussed theoretically and with regards to the socio-cultural sphere of Iranian society.

Direct and indirect effects of attention and visual function on gait impairment in Parkinson's disease: influence of task and turning.

PubMed

Stuart, Samuel; Galna, Brook; Delicato, Louise S; Lord, Sue; Rochester, Lynn

2017-07-01

Gait impairment is a core feature of Parkinson's disease (PD) which has been linked to cognitive and visual deficits, but interactions between these features are poorly understood. Monitoring saccades allows investigation of real-time cognitive and visual processes and their impact on gait when walking. This study explored: (i) saccade frequency when walking under different attentional manipulations of turning and dual-task; and (ii) direct and indirect relationships between saccades, gait impairment, vision and attention. Saccade frequency (number of fast eye movements per-second) was measured during gait in 60 PD and 40 age-matched control participants using a mobile eye-tracker. Saccade frequency was significantly reduced in PD compared to controls during all conditions. However, saccade frequency increased with a turn and decreased under dual-task for both groups. Poorer attention directly related to saccade frequency, visual function and gait impairment in PD, but not controls. Saccade frequency did not directly relate to gait in PD, but did in controls. Instead, saccade frequency and visual function deficit indirectly impacted gait impairment in PD, which was underpinned by their relationship with attention. In conclusion, our results suggest a vital role for attention with direct and indirect influences on gait impairment in PD. Attention directly impacted saccade frequency, visual function and gait impairment in PD, with connotations for falls. It also underpinned indirect impact of visual and saccadic impairment on gait. Attention therefore represents a key therapeutic target that should be considered in future research. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

14 CFR 296.2 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS INDIRECT AIR TRANSPORTATION OF PROPERTY General § 296.2 Applicability. This part applies to air transportation of property by indirect cargo air carriers, and to persons entering into control relationships...

An Optimal Control Modification to Model-Reference Adaptive Control for Fast Adaptation

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.; Krishnakumar, Kalmanje; Boskovic, Jovan

2008-01-01

This paper presents a method that can achieve fast adaptation for a class of model-reference adaptive control. It is well-known that standard model-reference adaptive control exhibits high-gain control behaviors when a large adaptive gain is used to achieve fast adaptation in order to reduce tracking error rapidly. High gain control creates high-frequency oscillations that can excite unmodeled dynamics and can lead to instability. The fast adaptation approach is based on the minimization of the squares of the tracking error, which is formulated as an optimal control problem. The necessary condition of optimality is used to derive an adaptive law using the gradient method. This adaptive law is shown to result in uniform boundedness of the tracking error by means of the Lyapunov s direct method. Furthermore, this adaptive law allows a large adaptive gain to be used without causing undesired high-gain control effects. The method is shown to be more robust than standard model-reference adaptive control. Simulations demonstrate the effectiveness of the proposed method.

How prescriptive support affects weight loss in weight-loss intervention participants and their untreated spouses.

PubMed

Cornelius, Talea; Gettens, Katelyn; Lenz, Erin; Wojtanowski, Alexis C; Foster, Gary D; Gorin, Amy A

2018-06-21

Controlling or prescriptive support styles (e.g., pressure) often hinder weight loss, but can sometimes be beneficial. This secondary analysis of data from a randomized controlled trial examined persuasion, pressure, and indirect social control among cohabiting couples and the effect of these supports on weight loss. Couples ( N Couples = 130) were randomized to either Weight Watchers (WW) or a self-guided control condition (SG). Only one member of each couple received the intervention; the other member of the couple was untreated. Couples were weighed and completed study measures at baseline, 3, and 6 months. Dyadic multilevel models examined BMI change and differences across role (treated participant/untreated spouse) and condition (WW/SG). Prescriptive support predicted BMI change for treated participants in the WW condition only. For treated WW participants, there was no significant decrease in BMI when pressure was high (+1 SD ), B = -.25, p = .22, but a significant decrease when pressure was low (0), B = -.96, p < .001. Additionally, high levels of indirect social control (+1 SD ) predicted greater decreases in BMI compared to low (-1 SD ) indirect social control, B = -.91, p < .001, and, B = -.41, p < .01. Considering both the type and context of support for weight management is worthwhile. Intervention participants had access to treatment resources that may have engendered more effective responses to spouses' concerns or a sense of obligation to their spouse (indirect social control), whereas pressures to lose weight-while engaged in treatment-may have undermined behavior-change efforts. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Estimation of Stability and Control Derivatives of an F-15

NASA Technical Reports Server (NTRS)

Smith, Mark; Moes, Tim

2006-01-01

A technique for real-time estimation of stability and control derivatives (derivatives of moment coefficients with respect to control-surface deflection angles) was used to support a flight demonstration of a concept of an indirect-adaptive intelligent flight control system (IFCS). Traditionally, parameter identification, including estimation of stability and control derivatives, is done post-flight. However, for the indirect-adaptive IFCS concept, parameter identification is required during flight so that the system can modify control laws for a damaged aircraft. The flight demonstration was carried out on a highly modified F-15 airplane (see Figure 1). The main objective was to estimate the stability and control derivatives of the airplane in nearly real time. A secondary goal was to develop a system to automatically assess the quality of the results, so as to be able to tell a learning neural network which data to use. Parameter estimation was performed by use of Fourier-transform regression (FTR) a technique developed at NASA Langley Research Center. FTR is an equation- error technique that operates in the frequency domain. Data are put into the frequency domain by use of a recursive Fourier transform for a discrete frequency set. This calculation simplifies many subsequent calculations, removes biases, and automatically filters out data beyond the chosen frequency range. FTR as applied here was tailored to work with pilot inputs, which produce correlated surface positions that prevent accurate parameter estimates, by replacing half the derivatives with predicted values. FTR was also set up to work only on a recent window of data, to accommodate changes in flight condition. A system of confidence measures was developed to identify quality-parameter estimates that a learning neural network could use. This system judged the estimates primarily on the basis of their estimated variances and of the level of aircraft response. The resulting FTR system was implemented in the Simulink software system and auto-coded in the C programming language for use on the Airborne Research Test System (ARTS II) computer installed in the F-15 airplane. The Simulink model was also used in a control room that utilizes the Ring Buffered Network Bus hardware and software, making it possible to evaluate test points during flights. In-flight parameter estimation was done for piloted and automated maneuvers, primarily at three test conditions. Figure 2 shows results for pitching moment due to symmetric stabilator actuations for a series of three pitch doublet maneuvers (in a doublet maneuver, a command to change attitude in a given direction by a given amount is followed immediately by a command to change attitude in the opposite direction by the same amount). A time window of 5 seconds was used. The portions of the curves shown in red are those that passed the confidence tests. The technique showed good convergence for most derivatives for both kinds of maneuvers - typically within a few seconds. The confidence tests were marginally successful, and it would be necessary to refine them for use in an IFCS.

Gene expression changes in the coccolithophore Emiliania huxleyi after 500 generations of selection to ocean acidification

PubMed Central

Lohbeck, Kai T.; Riebesell, Ulf; Reusch, Thorsten B. H.

2014-01-01

Coccolithophores are unicellular marine algae that produce biogenic calcite scales and substantially contribute to marine primary production and carbon export to the deep ocean. Ongoing ocean acidification particularly impairs calcifying organisms, mostly resulting in decreased growth and calcification. Recent studies revealed that the immediate physiological response in the coccolithophore Emiliania huxleyi to ocean acidification may be partially compensated by evolutionary adaptation, yet the underlying molecular mechanisms are currently unknown. Here, we report on the expression levels of 10 candidate genes putatively relevant to pH regulation, carbon transport, calcification and photosynthesis in E. huxleyi populations short-term exposed to ocean acidification conditions after acclimation (physiological response) and after 500 generations of high CO2 adaptation (adaptive response). The physiological response revealed downregulation of candidate genes, well reflecting the concomitant decrease of growth and calcification. In the adaptive response, putative pH regulation and carbon transport genes were up-regulated, matching partial restoration of growth and calcification in high CO2-adapted populations. Adaptation to ocean acidification in E. huxleyi likely involved improved cellular pH regulation, presumably indirectly affecting calcification. Adaptive evolution may thus have the potential to partially restore cellular pH regulatory capacity and thereby mitigate adverse effects of ocean acidification. PMID:24827439

Verification and Validation Challenges for Adaptive Flight Control of Complex Autonomous Systems

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2018-01-01

Autonomy of aerospace systems requires the ability for flight control systems to be able to adapt to complex uncertain dynamic environment. In spite of the five decades of research in adaptive control, the fact still remains that currently no adaptive control system has ever been deployed on any safety-critical or human-rated production systems such as passenger transport aircraft. The problem lies in the difficulty with the certification of adaptive control systems since existing certification methods cannot readily be used for nonlinear adaptive control systems. Research to address the notion of metrics for adaptive control began to appear in the recent years. These metrics, if accepted, could pave a path towards certification that would potentially lead to the adoption of adaptive control as a future control technology for safety-critical and human-rated production systems. Development of certifiable adaptive control systems represents a major challenge to overcome. Adaptive control systems with learning algorithms will never become part of the future unless it can be proven that they are highly safe and reliable. Rigorous methods for adaptive control software verification and validation must therefore be developed to ensure that adaptive control system software failures will not occur, to verify that the adaptive control system functions as required, to eliminate unintended functionality, and to demonstrate that certification requirements imposed by regulatory bodies such as the Federal Aviation Administration (FAA) can be satisfied. This presentation will discuss some of the technical issues with adaptive flight control and related V&V challenges.

What are the differences in driver injury outcomes at highway-rail grade crossings? Untangling the role of pre-crash behaviors.

PubMed

Liu, Jun; Khattak, Asad J; Richards, Stephen H; Nambisan, Shashi

2015-12-01

Crashes at highway-rail grade crossings can result in severe injuries and fatalities to vehicle occupants. Using a crash database from the Federal Railroad Administration (N=15,639 for 2004-2013), this study explores differences in safety outcomes from crashes between passive controls (Crossbucks and STOP signs) and active controls (flashing lights, gates, audible warnings and highway signals). To address missing data, an imputation model is developed, creating a complete dataset for estimation. Path analysis is used to quantify the direct and indirect associations of passive and active controls with pre-crash behaviors and crash outcomes in terms of injury severity. The framework untangles direct and indirect associations of controls by estimating two models, one for pre-crash driving behaviors (e.g., driving around active controls), and another model for injury severity. The results show that while the presence of gates is not directly associated with injury severity, the indirect effect through stopping behavior is statistically significant (95% confidence level) and substantial. Drivers are more likely to stop at gates that also have flashing lights and audible warnings, and stopping at gates is associated with lower injury severity. This indirect association lowers the chances of injury by 16%, compared with crashes at crossings without gates. Similar relationships between other controls and injury severity are explored. Generally, crashes occurring at active controls are less severe than crashes at passive controls. The results of study can be used to modify Crash Modification Factors (CMFs) to account for crash injury severity. The study contributes to enhancing the understanding of safety by incorporating pre-crash behaviors in a broader framework that quantifies correlates of crash injury severity at active and passive crossings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Parental Psychological Control and Adolescent Adjustment: The Role of Adolescent Emotion Regulation

PubMed Central

Cui, Lixian; Morris, Amanda Sheffield; Criss, Michael M.; Houltberg, Benjamin J.; Silk, Jennifer S.

2014-01-01

SYNOPSIS Objective This study investigated associations between parental psychological control and aggressive behavior and depressive symptoms among adolescents from predominantly disadvantaged backgrounds. The indirect effects of psychological control on adolescent adjustment through adolescent emotion regulation (anger and sadness regulation) were examined as well as the moderating effects of adolescent emotion regulation. Design 206 adolescents (ages 10–18) reported on parental psychological control and their own depressive symptoms, and parents and adolescents reported on adolescent emotion regulation and aggressive behavior. Indirect effect models were tested using structural equation modeling; moderating effects were tested using hierarchical multiple regression. Results The associations between parental psychological control and adolescent aggressive behavior and depressive symptoms were indirect through adolescents’ anger regulation. Moderation analyses indicated that the association between parental psychological control and adolescent depressive symptoms was stronger among adolescents with poor sadness regulation and the association between psychological control and aggressive behavior was stronger among older adolescents with poor anger regulation. Conclusions Psychological control is negatively associated with adolescent adjustment, particularly among adolescents who have difficulty regulating emotions. Emotion regulation is one mechanism through which psychological control is linked to adolescent adjustment, particularly anger dysregulation, and this pattern holds for both younger and older adolescents and for both boys and girls. PMID:25057264

Method and apparatus for adaptive force and position control of manipulators

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1989-01-01

The present invention discloses systematic methods and apparatus for the design of real time controllers. Real-time control employs adaptive force/position by use of feedforward and feedback controllers, with the feedforward controller being the inverse of the linearized model of robot dynamics and containing only proportional-double-derivative terms is disclosed. The feedback controller, of the proportional-integral-derivative type, ensures that manipulator joints follow reference trajectories and the feedback controller achieves robust tracking of step-plus-exponential trajectories, all in real time. The adaptive controller includes adaptive force and position control within a hybrid control architecture. The adaptive controller, for force control, achieves tracking of desired force setpoints, and the adaptive position controller accomplishes tracking of desired position trajectories. Circuits in the adaptive feedback and feedforward controllers are varied by adaptation laws.

Adaptive Flight Control Design with Optimal Control Modification on an F-18 Aircraft Model

NASA Technical Reports Server (NTRS)

Burken, John J.; Nguyen, Nhan T.; Griffin, Brian J.

2010-01-01

In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to as the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly; however, a large adaptive gain can lead to high-frequency oscillations which can adversely affect the robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient robustness. A damping term (v) is added in the modification to increase damping as needed. Simulations were conducted on a damaged F-18 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) with both the standard baseline dynamic inversion controller and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model.

Utility loss and indirect costs after stroke in Sweden.

PubMed

Lindgren, Peter; Glader, Eva-Lotta; Jönsson, Bengt

2008-04-01

Currently little data exist on the development of quality of life over time in patients suffering from stroke, in particular using instruments that can be adapted in economic studies. The purpose of the study was to assess the utility loss and indirect costs following a stroke in Sweden. A cross-sectional mail survey. In collaboration with the National Stroke registry (RIKS-STROKE), a questionnaire consisting of the EuroQol-5D and questions regarding the present working status and the status prior to the stroke was mailed to patients below 76 years of age at six participating centres. The questionnaire was mailed to 393 patients in total, divided into groups with 3, 6, 9 or 12 months having passed since the stroke. The EuroQol-5D scores were converted to utility scores using the UK social tariff. Indirect costs were valued according to the average salary+employer contributions. A total of 275 questionnaires (70%) were returned. Utility scores were similar over time: 0.65, 0.75, 0.63, and 0.67 at 3, 6, 9 and 12 months, respectively. Regression analyses revealed a tendency for lower utility scores among women, but no significant differences overall. Among patients in the working ages, a stroke caused 18.5 work weeks lost, corresponding to an indirect cost of 120,000 Swedish Kronor (SEK) (13,200euro, 95% confidence interval 82,541-160,050 SEK, 9080-17 605euro). Stroke causes a significant reduction in utility and causes high indirect costs. A substantial improvement was not noted over time, which is important to consider in economic models.

Computer-delivered indirect screening and brief intervention for drug use in the perinatal period: A randomized trial.

PubMed

Ondersma, Steven J; Svikis, Dace S; Thacker, Casey; Resnicow, Ken; Beatty, Jessica R; Janisse, James; Puder, Karoline

2018-04-01

Under-reporting of drug use in the perinatal period is well-documented, and significantly limits the reach of proactive intervention approaches. The Wayne Indirect Drug Use Screener (WIDUS) focuses on correlates of drug use rather than use itself. This trial tested a computer-delivered, brief intervention designed for use with indirect screen-positive cases, seeking to motivate reductions in drug use without presuming its presence. Randomized clinical trial with 500 WIDUS-positive postpartum women recruited between August 14, 2012 and November 19, 2014. Participants were randomly assigned to either a time control condition or a single-session, tailored, indirect brief intervention. The primary outcome was days of drug use over the 6-month follow-up period; secondary outcomes included urine and hair analyses results at 3- and 6-month follow-up. All outcomes were measured by blinded evaluators. Of the 500 participants (252 intervention and 248 control), 36.1% of participants acknowledged drug use in the 3 months prior to pregnancy, but 89% tested positive at the 6-month follow-up. Participants rated the intervention as easy to use (4.9/5) and helpful (4.4/5). Analyses revealed no between-group differences in drug use (52% in the intervention group, vs. 53% among controls; OR 1.03). Exploratory analyses also showed that intervention effects were not moderated by baseline severity, WIDUS score, or readiness to change. The present trial showed no evidence of efficacy for an indirect, single-session, computer-delivered, brief intervention designed as a complement to indirect screening. More direct approaches that still do not presume active drug use may be possible and appropriate. Copyright © 2018 Elsevier B.V. All rights reserved.

Direct and indirect ENSO modulation of winter temperature over the Asian–Pacific–American region

PubMed Central

Leung, Marco Y. T.; Zhou, Wen

2016-01-01

In this study, the direct and indirect atmospheric responses over the Asian–Pacific–American region to the El Niño–Southern Oscillation (ENSO) are documented. Since ENSO is likely to induce the northward displacement of the East Asian trough (NDEAT), some of the influence of ENSO on the Asian–Pacific–American region is possibly indirect and acts by inducing NDEAT. To separate corresponding influences of ENSO and NDEAT, partial regression is utilized. It is noted that temperature variations in the East Asian–Western Pacific region are controlled mainly by NDEAT. In contrast, ENSO demonstrates a weak direct relation to the temperature variation over the East Asian–Western Pacific region. This suggests that the influence of ENSO on this region is indirect, through modulation of NDEAT. On the other hand, temperature variation over the tropical eastern Pacific is dominated by ENSO forcing. Finally, temperature variation over the eastern North American–Western Pacific region is controlled by both ENSO and NDEAT. Nevertheless, their influences on temperature and circulation over this region tend to offset each other. This implies that temperature variation is controlled by their relative strengths. PMID:27821838

Energy-based adaptive focusing of waves: application to noninvasive aberration correction of ultrasonic wavefields

PubMed Central

Herbert, Eric; Pernot, Mathieu; Montaldo, Gabriel; Fink, Mathias; Tanter, Mickael

2009-01-01

An aberration correction method based on the maximization of the wave intensity at the focus of an emitting array is presented. The potential of this new adaptive focusing technique is investigated for ultrasonic focusing in biological tissues. The acoustic intensity is maximized non invasively through the direct measurement or indirect estimation of the beam energy at the focus for a series of spatially coded emissions. For ultrasonic waves, the acoustic energy at the desired focus can be indirectly estimated from the local displacements induced in tissues by the ultrasonic radiation force of the beam. Based on the measurement of these displacements, this method allows the precise estimation of the phase and amplitude aberrations and consequently the correction of aberrations along the beam travel path. The proof of concept is first performed experimentally using a large therapeutic array with strong electronic phase aberrations (up to 2π). Displacements induced by the ultrasonic radiation force at the desired focus are indirectly estimated using the time shift of backscattered echoes recorded on the array. The phase estimation is deduced accurately using a direct inversion algorithm which reduces the standard deviation of the phase distribution from σ = 1.89 before correction to σ = 0.53 following correction. The corrected beam focusing quality is verified using a needle hydrophone. The peak intensity obtained through the aberrator is found to be −7.69 dB below the reference intensity obtained without any aberration. Using the phase correction, a sharp focus is restored through the aberrator with a relative peak intensity of −0.89 dB. The technique is tested experimentally using a linear transmit/receive array through a real aberrating layer. The array is used to automatically correct its beam quality, as it both generates the radiation force with coded excitations and indirectly estimates the acoustic intensity at the focus with speckle tracking. This technique could have important implications in the field of High Intensity Focused Ultrasound even in complex configurations such as transcranial, transcostal or deep seated organs. PMID:19942526

Report on ESA Topical Team on the Large Radius Human Centrifuge: "The Human Hypergravity Habitat; H3"

NASA Astrophysics Data System (ADS)

van Loon, Jack J. W. A.; Bücker, N.; Berte, J.; Bok, K.; Bos, J.; Boyle, R.; Bravenoer, N.; Chouker, A.; Clement, G.; Cras, P.; Denise, D.; Eekhoff, M.; Felsenberg, D.; Fong, K.; Fuller, C.; Groen, E.; Heer, M.; Hinghofer-Szalkay, H.; Iwase, S.; Karemaker, J. M.; Linnarsson, D.; Lüthen, C.; Narici, M.; Norsk, P.; Paloski, W.; Rutten, M.; Saggini, R.; Stephan, A.; Ullrich, O.; Vautmans, V.; Wuyts, F.; Young, L.

Over the last decades a significant amount of knowledge has been accumulated on the adap-tation of the human body going into near weightless conditions and on its re-adaptation to 1g Earth conditions after space flight. Ground-based paradigms for microgravity simulation have been developed such as head down tilted bed rest and dry-immersion. In such systems the adaptations to long term immobilization and to head-ward fluid shifts have been studied. Questions we address here are: can long-term ground-based centrifugation help us to under-stand and even predict the adaptations to long-term increased gravity conditions? How does the body adapt to chronic (days, weeks or longer) exposure to a hypergravity environment? And, once the body has fully adapted to a hypergravity environment, how does it re-adapt going from a hypergravity state back to a relatively hypo-gravity condition of 1g, or even going from a centrifuge / hypergravity environment into a bed-rest setting? Can such transitions in well-controlled studies bring us closer to understanding the consequences of gravity transitions that the crews will likely experience going to the Moon or to Mars. Is hypergravity a good model to study the effect of re-entry in gravitational environments after long duration space flight? In an ESA -supported Topical Team we address all organ systems known so far to change directly or indirectly by altered gravity conditions. We will identify to which gravity levels the human body can be exposed for longer periods of time and what protocols could be applied to address the questions at hand. We also identify the technology required to ac-complish such long duration hypergravity and re-adaptation studies. Issues like ethics, safety and required logistics should be addressed. As there is limited experience with exposure of hu-man test subjects to prolonged periods of moderately increased g-forces, unexpected harm may occur. Therefore, the information, disclosure and informed consent procedures need special attention. The final outcome of the Topical Team will be a clear answer about the feasibility of the use of hypergravity as a tool and analogue for space research, and if and how hypergravity studies can provide useful knowledge to support future space flight on the one hand and current medical issues in the ageing population (osteoporosis, cardiovascular diseases, obesity) on the other hand.

Modeling posttraumatic growth among cancer patients: The roles of social support, appraisals, and adaptive coping.

PubMed

Cao, Weidan; Qi, Xiaona; Cai, Deborah A; Han, Xuanye

2018-01-01

The purpose of the study was to build a model to explain the relationships between social support, uncontrollability appraisal, adaptive coping, and posttraumatic growth (PTG) among cancer patients in China. The participants who were cancer patients in a cancer hospital in China filled out a survey. The final sample size was 201. Structural equation modeling was used to build a model explaining PTG. Structural equation modeling results indicated that higher levels of social support predicted higher levels of adaptive coping, higher levels of uncontrollability appraisal predicted lower levels of adaptive coping, and higher levels of adaptive coping predicted higher levels of PTG. Moreover, adaptive coping was a mediator between social support and growth, as well as a mediator between uncontrollability and growth. The direct effects of social support and uncontrollability on PTG were insignificant. The model demonstrated the relationships between social support, uncontrollability appraisal, adaptive coping, and PTG. It could be concluded that uncontrollability appraisal was a required but not sufficient condition for PTG. Neither social support nor uncontrollability appraisal had direct influence on PTG. However, social support and uncontrollability might indirectly influence PTG, through adaptive coping. It implies that both internal factors (eg, cognitive appraisal and coping) and external factors (eg, social support) are required in order for growth to happen. Copyright © 2017 John Wiley & Sons, Ltd.

Experimental Validation of L1 Adaptive Control: Rohrs' Counterexample in Flight

NASA Technical Reports Server (NTRS)

Xargay, Enric; Hovakimyan, Naira; Dobrokhodov, Vladimir; Kaminer, Issac; Kitsios, Ioannis; Cao, Chengyu; Gregory, Irene M.; Valavani, Lena

2010-01-01

The paper presents new results on the verification and in-flight validation of an L1 adaptive flight control system, and proposes a general methodology for verification and validation of adaptive flight control algorithms. The proposed framework is based on Rohrs counterexample, a benchmark problem presented in the early 80s to show the limitations of adaptive controllers developed at that time. In this paper, the framework is used to evaluate the performance and robustness characteristics of an L1 adaptive control augmentation loop implemented onboard a small unmanned aerial vehicle. Hardware-in-the-loop simulations and flight test results confirm the ability of the L1 adaptive controller to maintain stability and predictable performance of the closed loop adaptive system in the presence of general (artificially injected) unmodeled dynamics. The results demonstrate the advantages of L1 adaptive control as a verifiable robust adaptive control architecture with the potential of reducing flight control design costs and facilitating the transition of adaptive control into advanced flight control systems.

Cognitive-behavioral play therapy.

PubMed

Knell, S M

1998-03-01

Discusses cognitive-behavioral play therapy (CBPT), a developmentally sensitive treatment for young children that relies on flexibility, decreased expectation for verbalizations by the child, and increased reliance on experiential approaches. The development of CBPT for preschool-age children provides a relatively unique adaptation of cognitive therapy as it was originally developed for adults. CBPT typically contains a modeling component through which adaptive coping skills are demonstrated. Through the use of play, cognitive change is communicated indirectly, and more adaptive behaviors can be introduced to the child. Modeling is tailored for use with many specific cognitive and behavioral interventions. Generalization and response prevention are important features of CBPT. With minor modifications, many of the principles of cognitive therapy, as delineated for use with adults, are applicable to young children. Case examples are presented to highlight the application of CBPT. Although CBPT has a sound therapeutic base and utilizes proven techniques, more rigorous empirical scrutiny is needed.

Mechanisms of small intestinal adaptation.

PubMed

Jenkins, A P; Thompson, R P

1994-01-01

Luminal nutrition, hormonal factors and pancreaticobiliary secretions are probably the major mediators of small intestinal adaptation. Their actions, as discussed in this paper, are likely to be interrelated. Direct local enterotrophic effects cannot account for all the actions of luminal nutrients. Additionally, hormonal factors have been shown to contribute to indirect effects of luminal nutrients and enteroglucagon is a likely mediator of adaptive responses. Furthermore, epidermal growth factor is a peptide for which there is convincing evidence of an enterotrophic action. Attention is drawn to the fact that pancreaticobiliary secretions may have a physiological role in stimulating small intestinal mucosal proliferation. Other factors may also influence small intestinal mucosal proliferation (e.g. prostaglandins, neurovascular mechanisms, bacteria). Additionally, polyamines are crucial in initiating cell division in the small intestine, but the detailed mechanisms of their action require further clarification. Finally, a number of therapeutic applications of small intestinal epithelial cell proliferation are discussed.

Water Rockets and Indirect Measurement.

ERIC Educational Resources Information Center

Inman, Duane

1997-01-01

Describes an activity that teaches a number of scientific concepts including indirect measurement, Newton's third law of motion, manipulating and controlling variables, and the scientific method of inquiry. Uses process skills such as observation, inference, prediction, mensuration, and communication as well as problem solving and higher-order…

RegA Plays a Key Role in Oxygen-Dependent Establishment of Persistence and in Isocitrate Lyase Activity, a Critical Determinant of In vivo Brucella suis Pathogenicity

PubMed Central

Abdou, Elias; Jiménez de Bagüés, María P.; Martínez-Abadía, Ignacio; Ouahrani-Bettache, Safia; Pantesco, Véronique; Occhialini, Alessandra; Al Dahouk, Sascha; Köhler, Stephan; Jubier-Maurin, Véronique

2017-01-01

For aerobic human pathogens, adaptation to hypoxia is a critical factor for the establishment of persistent infections, as oxygen availability is low inside the host. The two-component system RegB/A of Brucella suis plays a central role in the control of respiratory systems adapted to oxygen deficiency, and in persistence in vivo. Using an original “in vitro model of persistence” consisting in gradual oxygen depletion, we compared transcriptomes and proteomes of wild-type and ΔregA strains to identify the RegA-regulon potentially involved in the set-up of persistence. Consecutive to oxygen consumption resulting in growth arrest, 12% of the genes in B. suis were potentially controlled directly or indirectly by RegA, among which numerous transcriptional regulators were up-regulated. In contrast, genes or proteins involved in envelope biogenesis and in cellular division were repressed, suggesting a possible role for RegA in the set-up of a non-proliferative persistence state. Importantly, the greatest number of the RegA-repressed genes and proteins, including aceA encoding the functional IsoCitrate Lyase (ICL), were involved in energy production. A potential consequence of this RegA impact may be the slowing-down of the central metabolism as B. suis progressively enters into persistence. Moreover, ICL is an essential determinant of pathogenesis and long-term interactions with the host, as demonstrated by the strict dependence of B. suis on ICL activity for multiplication and persistence during in vivo infection. RegA regulates gene or protein expression of all functional groups, which is why RegA is a key regulator of B. suis in adaptation to oxygen depletion. This function may contribute to the constraint of bacterial growth, typical of chronic infection. Oxygen-dependent activation of two-component systems that control persistence regulons, shared by several aerobic human pathogens, has not been studied in Brucella sp. before. This work therefore contributes significantly to the unraveling of persistence mechanisms in this important zoonotic pathogen. PMID:28573107

Management and Care of Women With Invasive Cervical Cancer: American Society of Clinical Oncology Resource-Stratified Clinical Practice Guideline.

PubMed

Chuang, Linus T; Temin, Sarah; Camacho, Rolando; Dueñas-Gonzalez, Alfonso; Feldman, Sarah; Gultekin, Murat; Gupta, Vandana; Horton, Susan; Jacob, Graciela; Kidd, Elizabeth A; Lishimpi, Kennedy; Nakisige, Carolyn; Nam, Joo-Hyun; Ngan, Hextan Yuen Sheung; Small, William; Thomas, Gillian; Berek, Jonathan S

2016-10-01

To provide evidence-based, resource-stratified global recommendations to clinicians and policymakers on the management and palliative care of women diagnosed with invasive cervical cancer. ASCO convened a multidisciplinary, multinational panel of cancer control, medical and radiation oncology, health economic, obstetric and gynecologic, and palliative care experts to produce recommendations reflecting resource-tiered settings. A systematic review of literature from 1966 to 2015 failed to yield sufficiently strong quality evidence to support basic- and limited-resource setting recommendations; a formal consensus-based process was used to develop recommendations. A modified ADAPTE process was also used to adapt recommendations from existing guidelines. Five existing sets of guidelines were identified and reviewed, and adapted recommendations form the evidence base. Eight systematic reviews, along with cost-effectiveness analyses, provided indirect evidence to inform the consensus process, which resulted in agreement of 75% or greater. Clinicians and planners should strive to provide access to the most effective evidence-based antitumor and palliative care interventions. If a woman cannot access these within her own or neighboring country or region, she may need to be treated with lower-tier modalities, depending on capacity and resources for surgery, chemotherapy, radiation therapy, and supportive and palliative care. For women with early-stage cervical cancer in basic settings, cone biopsy or extrafascial hysterectomy may be performed. Fertility-sparing procedures or modified radical or radical hysterectomy may be additional options in nonbasic settings. Combinations of surgery, chemotherapy, and radiation therapy (including brachytherapy) should be used for women with stage IB to IVA disease, depending on available resources. Pain control is a vital component of palliative care. Additional information is available at www.asco.org/rs-cervical-cancer-treatment-guideline and www.asco.org/guidelineswiki. It is the view of ASCO that health care providers and health care system decision makers should be guided by the recommendations for the highest stratum of resources available. The guideline is intended to complement but not replace local guidelines.

Effects of prescribed fire and season of burn on direct and indirect levels of tree mortality in Ponderosa and Jeffrey Pine Forests in California, USA.

Treesearch

Christopher Fettig; Stephen McKelvey; Daniel Cluck; Smith Sheri; William Otrosina

2010-01-01

Many forests that historically experienced frequent low-intensity wildfires have undergone extensive alterations during the past century. Prescribed fire is now commonly used to restore these fire-adapted forest ecosystems. In this study, we examined the influence of prescribed burn season on levels of tree mortality attributed to prescribed fire effects (direct...

Canadian Light Infantry in Adaptive Dispersed Operations

DTIC Science & Technology

2012-05-17

participated directly or indirectly under the leadership of Combined Joint Task Force (CJTF) MOUNTAIN, which was mostly built around the 10th Mountain...unique and possesses its own characteristics. It has its own ethic which is obtained from its distinctive tactical style , special attitude toward the...it is not organization that determines their light nature but their characteristics and fighting style . He added: “The historical tendency for light

Canadian Light Infantry in Adaptive Dispersed Operations

DTIC Science & Technology

2012-05-22

participated directly or indirectly under the leadership of Combined Joint Task Force (CJTF) MOUNTAIN, which was mostly built around the 10th Mountain...unique and possesses its own characteristics. It has its own ethic which is obtained from its distinctive tactical style , special attitude toward the...it is not organization that determines their light nature but their characteristics and fighting style . He added: “The historical tendency for light

Grandparent helpers: the adaptive significance of older, postdominant helpers in the Seychelles warbler.

PubMed

Richardson, David S; Burke, Terry; Komdeur, Jan

2007-12-01

The possibility that older, often nonreproductive, individuals may engage in kin-directed cooperative behavior has been largely overlooked in the study of cooperative breeding. Here, we describe and investigate the adaptive significance of such "grandparent" helpers in the Seychelles warbler, the first bird species in which this phenomenon has been observed. On Cousin Island, over a period of 24 years, a significant proportion (13.7%) of females, but few males (3.0%), was deposed from dominant positions. Deposed females were replaced by related females. However there was no evidence that older, senescent females were stepping aside to gain greater fitness benefits by increasing the reproductive success of their offspring, rather than breeding themselves; deposed females were not postreproductive, nor was being deposed linked to age or reproductive senescence. Of the deposed females, 68% became subordinates and helped to raise group offspring, accounting for ca. 10% of subordinates in any year. Demoted females were related (r= 0.24) to the group offspring and, consequently, could gain indirect benefits through helping. As direct benefits appeared to be limited, we suggest that indirect benefits have driven the evolution of such "grandparent helpers." This study now provides evidence for a new route to cooperative breeding in birds.

Bacterial adaptation to sublethal antibiotic gradients can change the ecological properties of multitrophic microbial communities

PubMed Central

Friman, Ville-Petri; Guzman, Laura Melissa; Reuman, Daniel C.; Bell, Thomas

2015-01-01

Antibiotics leak constantly into environments due to widespread use in agriculture and human therapy. Although sublethal concentrations are well known to select for antibiotic-resistant bacteria, little is known about how bacterial evolution cascades through food webs, having indirect effect on species not directly affected by antibiotics (e.g. via population dynamics or pleiotropic effects). Here, we used an experimental evolution approach to test how temporal patterns of antibiotic stress, as well as migration within metapopulations, affect the evolution and ecology of microcosms containing one prey bacterium, one phage and two protist predators. We found that environmental variability, autocorrelation and migration had only subtle effects for population and evolutionary dynamics. However, unexpectedly, bacteria evolved greatest fitness increases to both antibiotics and enemies when the sublethal levels of antibiotics were highest, indicating positive pleiotropy. Crucially, bacterial adaptation cascaded through the food web leading to reduced predator-to-prey abundance ratio, lowered predator community diversity and increased instability of populations. Our results show that the presence of natural enemies can modify and even reverse the effects of antibiotics on bacteria, and that antibiotic selection can change the ecological properties of multitrophic microbial communities by having indirect effects on species not directly affected by antibiotics. PMID:25833854

Bacterial adaptation to sublethal antibiotic gradients can change the ecological properties of multitrophic microbial communities.

PubMed

Friman, Ville-Petri; Guzman, Laura Melissa; Reuman, Daniel C; Bell, Thomas

2015-05-07

Antibiotics leak constantly into environments due to widespread use in agriculture and human therapy. Although sublethal concentrations are well known to select for antibiotic-resistant bacteria, little is known about how bacterial evolution cascades through food webs, having indirect effect on species not directly affected by antibiotics (e.g. via population dynamics or pleiotropic effects). Here, we used an experimental evolution approach to test how temporal patterns of antibiotic stress, as well as migration within metapopulations, affect the evolution and ecology of microcosms containing one prey bacterium, one phage and two protist predators. We found that environmental variability, autocorrelation and migration had only subtle effects for population and evolutionary dynamics. However, unexpectedly, bacteria evolved greatest fitness increases to both antibiotics and enemies when the sublethal levels of antibiotics were highest, indicating positive pleiotropy. Crucially, bacterial adaptation cascaded through the food web leading to reduced predator-to-prey abundance ratio, lowered predator community diversity and increased instability of populations. Our results show that the presence of natural enemies can modify and even reverse the effects of antibiotics on bacteria, and that antibiotic selection can change the ecological properties of multitrophic microbial communities by having indirect effects on species not directly affected by antibiotics. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Kinematically mediated effects of sport shoe design: a review.

PubMed

Frederick, E C

1986-01-01

One prominent pattern emerging from a review of the literature on sport shoes and biomechanics is the observation that many effects are the indirect result of shoe-induced adjustments in movement, i.e. a particular shoe characteristic elicits a kinematic adaptation which in turn has secondary consequences on kinetics and on injury and performance. For example, in addition to its variable effects on peak forces, cushioning system design has been shown to alter electromyographic patterns and to affect knee flexion during foot strike and affect indirectly the economy of running. Mediolateral stability as measured by rearfoot kinematics is strongly influenced by shoe design features such as heel lift, and sole hardness and geometry. The frictional properties of the shoe and surface interface have also been shown to affect kinematics in a way that in turn affects the recorded frictional forces themselves. Such kinematically mediated responses are the most provocative result of studies of the biomechanical effects of footwear. It is becoming apparent that the shoe can be a powerful tool for manipulating human movement. The abundance of shoe design possibilities coupled with the body's tendency to adjust in predictable ways to shoe mechanical characteristics have given us a new way to manipulate human kinematics and kinetics, as well as a convenient model for studying biomechanical adaptation.

Indirect fluorometric detection techniques on thin layer chromatography and effect of ultrasound on gel electrophoresis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yinfa, Ma.

Thin-layer chromatography (TLC) is a broadly applicable separation technique. It offers many advantages over high performance liquid chromatography (HPLC), such as easily adapted for two-dimensional separation, for whole-column'' detection and for handling multiple samples, etc. However, due to its draggy development of detection techniques comparing with HPLC, TLC has not received the attention it deserves. Therefore, exploring new detection techniques is very important to the development of TLC. It is the principal of this dissertation to present a new detection method for TLC -- indirect fluorometric detection method. This detection technique is universal sensitive, nondestructive, and simple. This will bemore » described in detail from Sections 1 through Section 5. Section 1 and 3 describe the indirect fluorometric detection of anions and nonelectrolytes in TLC. In Section 2, a detection method for cations based on fluorescence quenching of ethidium bromide is presented. In Section 4, a simple and interesting TLC experiment is designed, three different fluorescence detection principles are used for the determination of caffeine, saccharin and sodium benzoate in beverages. A laser-based indirect fluorometric detection technique in TLC is developed in Section 5. Section 6 is totally different from Sections 1 through 5. An ultrasonic effect on the separation of DNA fragments in agarose gel electrophoresis is investigated. 262 refs.« less

Gender-specific mediational links between parenting styles, parental monitoring, impulsiveness, drinking control, and alcohol-related problems.

PubMed

Patock-Peckham, Julie A; King, Kevin M; Morgan-Lopez, Antonio A; Ulloa, Emilio C; Moses, Jennifer M Filson

2011-03-01

Recently, it has been suggested that traits may dynamically change as conditions change. One possible mechanism that may influence impulsiveness is parental monitoring. Parental monitoring reflects a knowledge regarding one's offspring's whereabouts and social connections. The aim of this investigation was to examine potential gender-specific parental influences to impulsiveness (general behavioral control), control over one's own drinking (specific behavioral control), and alcohol-related problems among individuals in a period of emerging adulthood. Direct and mediational links between parenting styles (permissive, authoritarian, and authoritative), parental monitoring, impulsiveness, drinking control, and alcohol-related problems were investigated. A multiple-group, SEM model with (316 women, 265 men) university students was examined. In general, the overall pattern among male and female respondents was distinct. For daughters, perceptions of a permissive father were indirectly linked to more alcohol-related problems through lower levels of monitoring by fathers and more impulsive symptoms. Perceptions of an authoritative father were also indirectly linked to fewer impulsive symptoms through higher levels of monitoring by fathers among daughters. For men, perceptions of a permissive mother were indirectly linked to more alcohol-related problems through lower levels of monitoring by mothers and more impulsive symptoms. For sons, perceptions of mother authoritativeness were indirectly linked to fewer alcohol-related problems through more monitoring by mothers and fewer impulsive symptoms. Monitoring by an opposite-gender parent mediated the link between parenting styles (i.e., permissive, authoritative) on impulsiveness.

Superficial middle cerebral vein connection to the cavernous sinus is not infrequent in brain arteriovenous malformations: an argument against their congenital origin?

PubMed

Shotar, Eimad; Guédon, Alexis; Sourour, Nader; Di Maria, Federico; Gabrieli, Joseph; Nouet, Aurélien; Chiras, Jacques; Clarençon, Frédéric

2016-07-01

The aim of this study was to test the hypothesis that the superficial middle cerebral vein (SMCV) is frequently absent or fails to connect with the cavernous sinus (CS) in the presence of brain arteriovenous malformations (AVMs), a frequently reported argument for the congenital origin of brain AVMs. The SMCV was retrospectively compared between patients with a brain AVM and a control group. The presence or absence of the SMCV, its direct or indirect connection to the CS and its termination in a laterocavernous sinus (LCS), paracavernous sinus (PCS), or directly in the CS was studied on digital subtraction angiography. One hundred twenty-five left or right side carotid angiograms from 70 patients with a brain AVM were compared to 125 angiograms from 74 controls. The SMCV was present in 88 (70.4 %) cases in the brain AVM group and 96 (76.8 %) cases in controls (p = 0.25). The SMCV was connected directly or indirectly to the CS in 65 (52 %) cases in the brain AVM group and 65 (52 %) cases in controls (p = 1). When comparing the subgroup of carotid angiograms ipsilateral to a supratentorial AVM, no statistically significant difference was found with controls. In three of six cases in which a SMCV drained an AVM, the vein terminated directly or indirectly in the CS. No difference of SMCV presence and direct or indirect connection to the CS was found between patients with AVM and a control group. SMCV anatomy does not support the congenital origin of brain AVMs.

The economic consequences of irritable bowel syndrome: a US employer perspective.

PubMed

Leong, Stephanie A; Barghout, Victoria; Birnbaum, Howard G; Thibeault, Crystal E; Ben-Hamadi, Rym; Frech, Feride; Ofman, Joshua J

2003-04-28

The objective of this study was to measure the direct costs of treating irritable bowel syndrome (IBS) and the indirect costs in the workplace. This was accomplished through retrospective analysis of administrative claims data from a national Fortune 100 manufacturer, which includes all medical, pharmaceutical, and disability claims for the company's employees, spouses/dependents, and retirees. Patients with IBS were identified as individuals, aged 18 to 64 years, who received a primary code for IBS or a secondary code for IBS and a primary code for constipation or abdominal pain between January 1, 1996, and December 31, 1998. Of these patients with IBS, 93.7% were matched based on age, sex, employment status, and ZIP code to a control population of beneficiaries. Direct and indirect costs for patients with IBS were compared with those of matched controls. The average total cost (direct plus indirect) per patient with IBS was 4527 dollars in 1998 compared with 3276 dollars for a control beneficiary (P<.001). The average physician visit costs were 524 dollars and 345 dollars for patients with IBS and controls, respectively (P<.001). The average outpatient care costs to the employer were 1258 dollars and 742 dollars for patients with IBS and controls, respectively (P<.001). Medically related work absenteeism cost the employer 901 dollars on average per employee treated for IBS compared with 528 dollars on average per employee without IBS (P<.001). Irritable bowel syndrome is a significant financial burden on the employer that arises from an increase in direct and indirect costs compared with the control group.

Excess costs from functional somatic syndromes in Germany - An analysis using entropy balancing.

PubMed

Grupp, Helen; Kaufmann, Claudia; König, Hans-Helmut; Bleibler, Florian; Wild, Beate; Szecsenyi, Joachim; Herzog, Wolfgang; Schellberg, Dieter; Schäfert, Rainer; Konnopka, Alexander

2017-06-01

The aim of this study was to calculate disorder-specific excess costs in patients with functional somatic syndromes (FSS). We compared 6-month direct and indirect costs in a patient group with FSS (n=273) to a control group of the general adult population in Germany without FSS (n=2914). Data on the patient group were collected between 2007 and 2009 in a randomized controlled trial (speciAL). Data on the control group were obtained from a telephone survey, representative for the general German population, conducted in 2014. Covariate balance between the patient group and the control group was achieved using entropy balancing. Excess costs were calculated by estimating generalized linear models and two-part models for direct costs and indirect costs. Further, we estimated excess costs according to the level of somatic symptom severity (SSS). FSS patients differed significantly from the control group regarding 6-month costs of outpatient physicians (+€280) and other outpatient providers (+€74). According to SSS, significantly higher outpatient physician costs were found for mild (+€151), moderate (+€306) and severe (+€376) SSS. We also found significantly higher costs of other outpatient providers in patients with mild, moderate and severe SSS. Regarding costs of rehabilitation and hospital treatments, FSS patients did not differ significantly from the control group for any level of SSS. Indirect costs were significantly higher in patients with severe SSS (+€760). FSS were of major importance in the outpatient sector. Further, we found significantly higher indirect costs in patients with severe SSS. Copyright © 2017 Elsevier Inc. All rights reserved.

Effects of depression, diabetes distress, diabetes self-efficacy, and diabetes self-management on glycemic control among Chinese population with type 2 diabetes mellitus.

PubMed

Lin, Keke; Park, Chang; Li, Mingzi; Wang, Xiudong; Li, Xiushu; Li, Wei; Quinn, Laurie

2017-09-01

To examine the direct and indirect effects of depression, diabetes distress, diabetes self-efficacy and diabetes self-management on glycemic control among a group of T2DM patients in China. A convenience sample of 254 participants were selected from three outpatient departments in Beijing, China. They were surveyed using a self-administered questionnaire. Diabetes-related information was retrieved from their medical records. Descriptive statistics, independent student t tests, Chi-square tests, correlation analyses and Generalized Structural Equation Modeling were used. Only 91 (35.82%) participants achieved optimal glycemic control of HbA1c<7.0% (53mmol/mol). Only diabetes self-management had a direct effect on glycemic control (OR=0.95, P<0.001). Depression and diabetes distress had only indirect effects on glycemic control through both diabetes self-efficacy and diabetes self-management. Diabetes self-efficacy only had an indirect effect on glycemic control through diabetes self-management. Glycemic control among Chinese population with T2DM was suboptimal. Future interventions should focus on decreasing depressive symptoms and diabetes distress levels, and, therefore, improve diabetes self-efficacy and self-management practices and, ultimately, reach the optimal goal of glycemic control. Copyright © 2017 Elsevier B.V. All rights reserved.

Socioeconomic status and quality of life among Chinese American breast cancer survivors: The mediating roles of social support and social constraints.

PubMed

You, Jin; Wang, Carol; Yeung, Nelson Chun Yiu; Lu, Qian

2018-03-30

Literature has well noted ethnic/racial disparities in cancer survival and cancer care. However, socioeconomic disparities in psychosocial adjustment to breast cancer have garnered little attention. This study addresses the research gap by investigating the associations between socioeconomic indicators (ie, education, annual personal, and household income) and quality of life (QOL) and the mediating roles of social support and social constraints (objective and subjective conditions that constrain individuals from disclosing cancer concerns) in these associations among Chinese American breast cancer survivors (CABCS). Ninety-six CABCS completed questionnaires assessing these variables. After controlling for stage of cancer, annual personal and household income had indirect effects on QOL through social support, and education showed indirect effect on QOL through social support and social constraints. Subscale analyses indicated that controlling for years of immigration, annual personal and household income showed indirect effect on functional well-being through social support. When controlling for stage of cancer and income, education showed indirect effects on physical well-being through social support and social constraints and showed both direct and indirect effects on breast cancer concerns through social constraints. This study suggested that socioeconomic indicators, education, and income could be associated with different aspects of QOL through unique interpersonal mechanisms among CABCS. Our findings implied that increasing social support and reducing social constraints when implementing psychosocial interventions for CABCS may help to address the SES-related health disparities. Copyright © 2018 John Wiley & Sons, Ltd.

Geographic variation in climate as a proxy for climate change: Forecasting evolutionary trajectories from species differentiation and genetic correlations.

PubMed

Schneider, Heather E; Mazer, Susan J

2016-01-01

Climate change models for California predict a warmer, drier future, potentially resulting in shorter growing seasons. If phenotypic differences between closely related species currently distributed across a moisture and temperature gradient represent adaptations to their abiotic environment, then as conditions become warmer and drier, populations presently adapted to cooler and wetter conditions may evolve to become more similar to those adapted to warmer and drier conditions. Two sister species, Clarkia unguiculata and C. exilis, are distributed across a moisture and temperature gradient in the southern Sierra Nevada, providing an opportunity to predict how this process may occur. In a greenhouse experiment using wild-collected seeds from 11 populations in the southern Sierra Nevada, we examined relationships among elevation, climatic conditions, and population means for each trait, then evaluated bivariate relationships among maternal family means, using raw values and controlling for population and seed mass effects on phenotype. Clarkia exilis occupied warmer, drier conditions, typically at lower elevations, than C. unguiculata did and flowered earlier and faster, producing smaller flowers with lower herkogamy. In C. unguiculata, petal area, herkogamy, and the rate of flower production were positively correlated with days to first flower. If selection favors earlier flowering, smaller petals, or faster flower production in C. unguiculata, then the genetic correlations among these traits should reinforce their joint evolution. Moreover, the correlations between these traits and herkogamy may promote the evolution of self-fertilization as an indirect response to selection, a previously unrecognized potential outcome of climate change. © 2016 Botanical Society of America.

Adaptive control applied to Space Station attitude control system

NASA Technical Reports Server (NTRS)

Lam, Quang M.; Chipman, Richard; Hu, Tsay-Hsin G.; Holmes, Eric B.; Sunkel, John

1992-01-01

This paper presents an adaptive control approach to enhance the performance of current attitude control system used by the Space Station Freedom. The proposed control law was developed based on the direct adaptive control or model reference adaptive control scheme. Performance comparisons, subject to inertia variation, of the adaptive controller and the fixed-gain linear quadratic regulator currently implemented for the Space Station are conducted. Both the fixed-gain and the adaptive gain controllers are able to maintain the Station stability for inertia variations of up to 35 percent. However, when a 50 percent inertia variation is applied to the Station, only the adaptive controller is able to maintain the Station attitude.

Evolution of an adaptive behavior and its sensory receptors promotes eye regression in blind cavefish.

PubMed

Yoshizawa, Masato; Yamamoto, Yoshiyuki; O'Quin, Kelly E; Jeffery, William R

2012-12-27

How and why animals lose eyesight during adaptation to the dark and food-limited cave environment has puzzled biologists since the time of Darwin. More recently, several different adaptive hypotheses have been proposed to explain eye degeneration based on studies in the teleost Astyanax mexicanus, which consists of blind cave-dwelling (cavefish) and sighted surface-dwelling (surface fish) forms. One of these hypotheses is that eye regression is the result of indirect selection for constructive characters that are negatively linked to eye development through the pleiotropic effects of Sonic Hedgehog (SHH) signaling. However, subsequent genetic analyses suggested that other mechanisms also contribute to eye regression in Astyanax cavefish. Here, we introduce a new approach to this problem by investigating the phenotypic and genetic relationships between a suite of non-visual constructive traits and eye regression. Using quantitative genetic analysis of crosses between surface fish, the Pachón cavefish population and their hybrid progeny, we show that the adaptive vibration attraction behavior (VAB) and its sensory receptors, superficial neuromasts (SN) specifically found within the cavefish eye orbit (EO), are genetically correlated with reduced eye size. The quantitative trait loci (QTL) for these three traits form two clusters of congruent or overlapping QTL on Astyanax linkage groups (LG) 2 and 17, but not at the shh locus on LG 13. Ablation of EO SN in cavefish demonstrated a major role for these sensory receptors in VAB expression. Furthermore, experimental induction of eye regression in surface fish via shh overexpression showed that the absence of eyes was insufficient to promote the appearance of VAB or EO SN. We conclude that natural selection for the enhancement of VAB and EO SN indirectly promotes eye regression in the Pachón cavefish population through an antagonistic relationship involving genetic linkage or pleiotropy among the genetic factors underlying these traits. This study demonstrates a trade-off between the evolution of a non-visual sensory system and eye regression during the adaptive evolution of Astyanax to the cave environment.

Striatal Mechanisms Underlying Movement, Reinforcement, and Punishment

PubMed Central

Kravitz, Alexxai V.; Kreitzer, Anatol C.

2013-01-01

Direct and indirect pathway striatal neurons are known to exert opposing control over motor output. In this review, we discuss a hypothetical extension of this framework, in which direct pathway striatal neurons also mediate reinforcement and reward, and indirect pathway neurons mediate punishment and aversion. PMID:22689792

Inconsistency between direct and indirect comparisons of competing interventions: meta-epidemiological study.

PubMed

Song, Fujian; Xiong, Tengbin; Parekh-Bhurke, Sheetal; Loke, Yoon K; Sutton, Alex J; Eastwood, Alison J; Holland, Richard; Chen, Yen-Fu; Glenny, Anne-Marie; Deeks, Jonathan J; Altman, Doug G

2011-08-16

To investigate the agreement between direct and indirect comparisons of competing healthcare interventions. Meta-epidemiological study based on sample of meta-analyses of randomised controlled trials. Data sources Cochrane Database of Systematic Reviews and PubMed. Inclusion criteria Systematic reviews that provided sufficient data for both direct comparison and independent indirect comparisons of two interventions on the basis of a common comparator and in which the odds ratio could be used as the outcome statistic. Inconsistency measured by the difference in the log odds ratio between the direct and indirect methods. The study included 112 independent trial networks (including 1552 trials with 478,775 patients in total) that allowed both direct and indirect comparison of two interventions. Indirect comparison had already been explicitly done in only 13 of the 85 Cochrane reviews included. The inconsistency between the direct and indirect comparison was statistically significant in 16 cases (14%, 95% confidence interval 9% to 22%). The statistically significant inconsistency was associated with fewer trials, subjectively assessed outcomes, and statistically significant effects of treatment in either direct or indirect comparisons. Owing to considerable inconsistency, many (14/39) of the statistically significant effects by direct comparison became non-significant when the direct and indirect estimates were combined. Significant inconsistency between direct and indirect comparisons may be more prevalent than previously observed. Direct and indirect estimates should be combined in mixed treatment comparisons only after adequate assessment of the consistency of the evidence.

Inconsistency between direct and indirect comparisons of competing interventions: meta-epidemiological study

PubMed Central

Xiong, Tengbin; Parekh-Bhurke, Sheetal; Loke, Yoon K; Sutton, Alex J; Eastwood, Alison J; Holland, Richard; Chen, Yen-Fu; Glenny, Anne-Marie; Deeks, Jonathan J; Altman, Doug G

2011-01-01

Objective To investigate the agreement between direct and indirect comparisons of competing healthcare interventions. Design Meta-epidemiological study based on sample of meta-analyses of randomised controlled trials. Data sources Cochrane Database of Systematic Reviews and PubMed. Inclusion criteria Systematic reviews that provided sufficient data for both direct comparison and independent indirect comparisons of two interventions on the basis of a common comparator and in which the odds ratio could be used as the outcome statistic. Main outcome measure Inconsistency measured by the difference in the log odds ratio between the direct and indirect methods. Results The study included 112 independent trial networks (including 1552 trials with 478 775 patients in total) that allowed both direct and indirect comparison of two interventions. Indirect comparison had already been explicitly done in only 13 of the 85 Cochrane reviews included. The inconsistency between the direct and indirect comparison was statistically significant in 16 cases (14%, 95% confidence interval 9% to 22%). The statistically significant inconsistency was associated with fewer trials, subjectively assessed outcomes, and statistically significant effects of treatment in either direct or indirect comparisons. Owing to considerable inconsistency, many (14/39) of the statistically significant effects by direct comparison became non-significant when the direct and indirect estimates were combined. Conclusions Significant inconsistency between direct and indirect comparisons may be more prevalent than previously observed. Direct and indirect estimates should be combined in mixed treatment comparisons only after adequate assessment of the consistency of the evidence. PMID:21846695

English v. General Electric Company: The state right to regulate the nuclear energy industry affirmed - (albeit indirect)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bogdan, W.

1991-12-31

The early history of the nuclear energy industry is dominated by almost exclusive federal government control and regulation. In the broadest sense, that history remains intact. Recent Supreme Court decisions, however, indicate that states are now capable of indirect regulation of the nuclear energy industry. English v. General Electric is such an example of a judicial decision with the potential to empower states with an opportunity to indirectly regulate the nuclear energy industry.

Indirect competitive assays on DVD for direct multiplex detection of drugs of abuse in oral fluids.

PubMed

Zhang, Lingling; Li, Xiaochun; Li, Yunchao; Shi, Xiaoli; Yu, Hua-Zhong

2015-02-03

On-site oral fluid testing for drugs of abuse has become prominent in order to take immediate administrative action in an enforcement process. Herein, we report a DVD technology-based indirect competitive immunoassay platform for the quantitative detection of drugs of abuse. A microfluidic approach was adapted to prepare multiplex immunoassays on a standard DVD-R, an unmodified multimode DVD/Blu-Ray drive to read signal, and a free disc-quality analysis software program to process the data. The DVD assay platform was successfully demonstrated for the simultaneous, quantitative detection of drug candidates (morphine and cocaine) in oral fluids with high selectivity. The detection limit achieved was as low as 1.0 ppb for morphine and 5.0 ppb for cocaine, comparable with that of standard mass spectrometry and ELISA methods.

Spatio-temporal Reconstruction of Neural Sources Using Indirect Dominant Mode Rejection.

PubMed

Jafadideh, Alireza Talesh; Asl, Babak Mohammadzadeh

2018-04-27

Adaptive minimum variance based beamformers (MVB) have been successfully applied to magnetoencephalogram (MEG) and electroencephalogram (EEG) data to localize brain activities. However, the performance of these beamformers falls down in situations where correlated or interference sources exist. To overcome this problem, we propose indirect dominant mode rejection (iDMR) beamformer application in brain source localization. This method by modifying measurement covariance matrix makes MVB applicable in source localization in the presence of correlated and interference sources. Numerical results on both EEG and MEG data demonstrate that presented approach accurately reconstructs time courses of active sources and localizes those sources with high spatial resolution. In addition, the results of real AEF data show the good performance of iDMR in empirical situations. Hence, iDMR can be reliably used for brain source localization especially when there are correlated and interference sources.

Animal contact as a source of human non-typhoidal salmonellosis

PubMed Central

2011-01-01

Non-typhoidal Salmonella represents an important human and animal pathogen world-wide. Most human salmonellosis cases are foodborne, but each year infections are also acquired through direct or indirect animal contact in homes, veterinary clinics, zoological gardens, farm environments or other public, professional or private settings. Clinically affected animals may exhibit a higher prevalence of shedding than apparently healthy animals, but both can shed Salmonella over long periods of time. In addition, environmental contamination and indirect transmission through contaminated food and water may complicate control efforts. The public health risk varies by animal species, age group, husbandry practice and health status, and certain human subpopulations are at a heightened risk of infection due to biological or behavioral risk factors. Some serotypes such as Salmonella Dublin are adapted to individual host species, while others, for instance Salmonella Typhimurium, readily infect a broad range of host species, but the potential implications for human health are currently unclear. Basic hygiene practices and the implementation of scientifically based management strategies can efficiently mitigate the risks associated with animal contacts. However, the general public is frequently unaware of the specific disease risks involved, and high-risk behaviors are common. Here we describe the epidemiology and serotype distribution of Salmonella in a variety of host species. In addition, we review our current understanding of the public health risks associated with different types of contacts between humans and animals in public, professional or private settings, and, where appropriate, discuss potential risk mitigation strategies. PMID:21324103

Examining a conceptual model of parental nurturance, parenting practices and physical activity among 5-6 year olds.

PubMed

Sebire, Simon J; Jago, Russell; Wood, Lesley; Thompson, Janice L; Zahra, Jezmond; Lawlor, Deborah A

2016-01-01

Parenting is an often-studied correlate of children's physical activity, however there is little research examining the associations between parenting styles, practices and the physical activity of younger children. This study aimed to investigate whether physical activity-based parenting practices mediate the association between parenting styles and 5-6 year-old children's objectively-assessed physical activity. 770 parents self-reported parenting style (nurturance and control) and physical activity-based parenting practices (logistic and modeling support). Their 5-6 year old child wore an accelerometer for five days to measure moderate-to-vigorous physical activity (MVPA). Linear regression was used to examine direct and indirect (mediation) associations. Data were collected in the United Kingdom in 2012/13 and analyzed in 2014. Parent nurturance was positively associated with provision of modeling (adjusted unstandardized coefficient, β = 0.11; 95% CI = 0.02, 0.21) and logistic support (β = 0.14; 0.07, 0.21). Modeling support was associated with greater child MVPA (β = 2.41; 0.23, 4.60) and a small indirect path from parent nurturance to child's MVPA was identified (β = 0.27; 0.04, 0.70). Physical activity-based parenting practices are more strongly associated with 5-6 year old children's MVPA than parenting styles. Further research examining conceptual models of parenting is needed to understand in more depth the possible antecedents to adaptive parenting practices beyond parenting styles. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

The Invasive American Weed Parthenium hysterophorus Can Negatively Impact Malaria Control in Africa.

PubMed

Nyasembe, Vincent O; Cheseto, Xavier; Kaplan, Fatma; Foster, Woodbridge A; Teal, Peter E A; Tumlinson, James H; Borgemeister, Christian; Torto, Baldwyn

2015-01-01

The direct negative effects of invasive plant species on agriculture and biodiversity are well known, but their indirect effects on human health, and particularly their interactions with disease-transmitting vectors, remains poorly explored. This study sought to investigate the impact of the invasive Neotropical weed Parthenium hysterophorus and its toxins on the survival and energy reserves of the malaria vector Anopheles gambiae. In this study, we compared the fitness of An. gambiae fed on three differentially attractive mosquito host plants and their major toxins; the highly aggressive invasive Neotropical weed Parthenium hysterophorus (Asteraceae) in East Africa and two other adapted weeds, Ricinus communis (Euphorbiaceae) and Bidens pilosa (Asteraceae). Our results showed that female An. gambiae fitness varied with host plants as females survived better and accumulated substantial energy reserves when fed on P. hysterophorus and R. communis compared to B. pilosa. Females tolerated parthenin and 1-phenylhepta-1, 3, 5-triyne, the toxins produced by P. hysterophorus and B. pilosa, respectively, but not ricinine produced by R. communis. Given that invasive plants like P. hysterophorus can suppress or even replace less competitive species that might be less suitable host-plants for arthropod disease vectors, the spread of invasive plants could lead to higher disease transmission. Parthenium hysterophorus represents a possible indirect effect of invasive plants on human health, which underpins the need to include an additional health dimension in risk-analysis modelling for invasive plants.

The Invasive American Weed Parthenium hysterophorus Can Negatively Impact Malaria Control in Africa

PubMed Central

Nyasembe, Vincent O.; Cheseto, Xavier; Kaplan, Fatma; Foster, Woodbridge A.; Teal, Peter E. A.; Tumlinson, James H.; Borgemeister, Christian; Torto, Baldwyn

2015-01-01

The direct negative effects of invasive plant species on agriculture and biodiversity are well known, but their indirect effects on human health, and particularly their interactions with disease-transmitting vectors, remains poorly explored. This study sought to investigate the impact of the invasive Neotropical weed Parthenium hysterophorus and its toxins on the survival and energy reserves of the malaria vector Anopheles gambiae. In this study, we compared the fitness of An. gambiae fed on three differentially attractive mosquito host plants and their major toxins; the highly aggressive invasive Neotropical weed Parthenium hysterophorus (Asteraceae) in East Africa and two other adapted weeds, Ricinus communis (Euphorbiaceae) and Bidens pilosa (Asteraceae). Our results showed that female An. gambiae fitness varied with host plants as females survived better and accumulated substantial energy reserves when fed on P. hysterophorus and R. communis compared to B. pilosa. Females tolerated parthenin and 1-phenylhepta-1, 3, 5-triyne, the toxins produced by P. hysterophorus and B. pilosa, respectively, but not ricinine produced by R. communis. Given that invasive plants like P. hysterophorus can suppress or even replace less competitive species that might be less suitable host-plants for arthropod disease vectors, the spread of invasive plants could lead to higher disease transmission. Parthenium hysterophorus represents a possible indirect effect of invasive plants on human health, which underpins the need to include an additional health dimension in risk-analysis modelling for invasive plants. PMID:26367123

Cultural adaptation of an intervention to reduce sexual risk behaviors among patients attending a STI clinic in St. Petersburg, Russia.

PubMed

Grau, Lauretta E; Krasnoselskikh, Tatiana V; Shaboltas, Alla V; Skochilov, Roman V; Kozlov, Andrei P; Abdala, Nadia

2013-08-01

Cultural adaptation is an important step in the process of implementing health promotion interventions that, having been proven to be effective in one culture, are being applied in another. This study describes the results of a formative investigation to culturally adapt a STI/HIV risk reduction intervention for use in St. Petersburg, Russia. Analyses of data from brief elicitation interviews, focus groups, community experts, and a pilot test of the adapted intervention identified environmental, cognitive-information processing, and affect-motivation factors that needed to be addressed during the adaptation process. The participant/counselor relationship was adapted to reflect a hierarchical (cf. collaborative) relationship in order to accommodate Russian expectations about patient interactions with healthcare experts. Key skills building activities (e.g., identification of personal risk behaviors, role-playing) were approached gradually or indirectly in order to maintain participants' engagement in the intervention, and close-ended questions were added to assist participants in understanding unfamiliar concepts such as "triggers" and self-efficacy. Information about the prevalence of HIV/STI infections and alcohol use included data specific to St. Petersburg to increase the personal relevance of these materials and messages. Intervention components were tailored to participants' risk reduction and informational needs. No gender differences that would have justified adaptation of the intervention approach or content were noted. Examples of specific adaptations and the key issues to attend to when adapting behavioral interventions for use in Russian clinical settings are discussed.

Advances in Adaptive Control Methods

NASA Technical Reports Server (NTRS)

Nguyen, Nhan

2009-01-01

This poster presentation describes recent advances in adaptive control technology developed by NASA. Optimal Control Modification is a novel adaptive law that can improve performance and robustness of adaptive control systems. A new technique has been developed to provide an analytical method for computing time delay stability margin for adaptive control systems.

Pilot Evaluation of Adaptive Control in Motion-Based Flight Simulator

NASA Technical Reports Server (NTRS)

Kaneshige, John T.; Campbell, Stefan Forrest

2009-01-01

The objective of this work is to assess the strengths, weaknesses, and robustness characteristics of several MRAC (Model-Reference Adaptive Control) based adaptive control technologies garnering interest from the community as a whole. To facilitate this, a control study using piloted and unpiloted simulations to evaluate sensitivities and handling qualities was conducted. The adaptive control technologies under consideration were ALR (Adaptive Loop Recovery), BLS (Bounded Linear Stability), Hybrid Adaptive Control, L1, OCM (Optimal Control Modification), PMRAC (Predictor-based MRAC), and traditional MRAC

Adaptive control of a Stewart platform-based manipulator

NASA Technical Reports Server (NTRS)

Nguyen, Charles C.; Antrazi, Sami S.; Zhou, Zhen-Lei; Campbell, Charles E., Jr.

1993-01-01

A joint-space adaptive control scheme for controlling noncompliant motion of a Stewart platform-based manipulator (SPBM) was implemented in the Hardware Real-Time Emulator at Goddard Space Flight Center. The six-degrees of freedom SPBM uses two platforms and six linear actuators driven by dc motors. The adaptive control scheme is based on proportional-derivative controllers whose gains are adjusted by an adaptation law based on model reference adaptive control and Liapunov direct method. It is concluded that the adaptive control scheme provides superior tracking capability as compared to fixed-gain controllers.

High speed flux feedback for tuning a universal field oriented controller capable of operating in direct and indirect field orientation modes

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Doncker, Rik W. A. A.

The direct (d) and quadrature (q) components of flux, as sensed by flux sensors or determined from voltage and current measurements in a direct field orientation scheme, are processed rapidly and accurately to provide flux amplitude and angular position values for use by the vector rotator of a universal field-oriented (UFO) controller. Flux amplitude (linear or squared) is provided as feedback to tune the UFO controller for operation in direct and indirect field orientation modes and enables smooth transitions from one mode to the other.

High speed flux feedback for tuning a universal field oriented controller capable of operating in direct and indirect field orientation modes

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Doncker, R.W.A.A.

The direct (d) and quadrature (q) components of flux, as sensed by flux sensors or determined from voltage and current measurements in a direct field orientation scheme, are processed rapidly and accurately to provide flux amplitude and angular position values for use by the vector rotator of a universal field-oriented (UFO) controller. Flux amplitude (linear or squared) is provided as feedback to tune the UFO controller for operation in direct and indirect field orientation modes and enables smooth transitions from one mode to the other. 3 figs.

High speed flux feedback for tuning a universal field oriented controller capable of operating in direct and indirect field orientation modes

DOEpatents

De Doncker, R.W.A.A.

1992-09-01

The direct (d) and quadrature (q) components of flux, as sensed by flux sensors or determined from voltage and current measurements in a direct field orientation scheme, are processed rapidly and accurately to provide flux amplitude and angular position values for use by the vector rotator of a universal field-oriented (UFO) controller. Flux amplitude (linear or squared) is provided as feedback to tune the UFO controller for operation in direct and indirect field orientation modes and enables smooth transitions from one mode to the other. 3 figs.

Dual-arm manipulators with adaptive control

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1991-01-01

The described and improved multi-arm invention of this application presents three strategies for adaptive control of cooperative multi-arm robots which coordinate control over a common load. In the position-position control strategy, the adaptive controllers ensure that the end-effector positions of both arms track desired trajectories in Cartesian space despite unknown time-varying interaction forces exerted through a load. In the position-hybrid control strategy, the adaptive controller of one arm controls end-effector motions in the free directions and applied forces in the constraint directions; while the adaptive controller of the other arm ensures that the end-effector tracks desired position trajectories. In the hybrid-hybrid control strategy, the adaptive controllers ensure that both end-effectors track reference position trajectories while simultaneously applying desired forces on the load. In all three control strategies, the cross-coupling effects between the arms are treated as disturbances which are compensated for by the adaptive controllers while following desired commands in a common frame of reference. The adaptive controllers do not require the complex mathematical model of the arm dynamics or any knowledge of the arm dynamic parameters or the load parameters such as mass and stiffness. Circuits in the adaptive feedback and feedforward controllers are varied by novel adaptation laws.

Method and apparatus for adaptive force and position control of manipulators

NASA Technical Reports Server (NTRS)

Seraji, Homayoun (Inventor)

1995-01-01

The described and improved multi-arm invention of this application presents three strategies for adaptive control of cooperative multi-arm robots which coordinate control over a common load. In the position-position control strategy, the adaptive controllers ensure that the end-effector positions of both arms track desired trajectories in Cartesian space despite unknown time-varying interaction forces exerted through a load. In the position-hybrid control strategy, the adaptive controller of one arm controls end-effector motions in the free directions and applied forces in the constraint directions; while the adaptive controller of the other arm ensures that the end-effector tracks desired position trajectories. In the hybrid-hybrid control strategy, the adaptive controllers ensure that both end-effectors track reference position trajectories while simultaneously applying desired forces on the load. In all three control strategies, the cross-coupling effects between the arms are treated as disturbances which are compensated for by the adaptive controllers while following desired commands in a common frame of reference. The adaptive controllers do not require the complex mathematical model of the arm dynamics or any knowledge of the arm dynamic parameters or the load parameters such as mass and stiffness. Circuits in the adaptive feedback and feedforward controllers are varied by novel adaptation laws.

Climate Change, Drought and Human Health in Canada

PubMed Central

Yusa, Anna; Berry, Peter; Cheng, June J.; Ogden, Nicholas; Bonsal, Barrie; Stewart, Ronald; Waldick, Ruth

2015-01-01

Droughts have been recorded all across Canada and have had significant impacts on individuals and communities. With climate change, projections suggest an increasing risk of drought in Canada, particularly in the south and interior. However, there has been little research on the impacts of drought on human health and the implications of a changing climate. A review of the Canadian, U.S. and international literature relevant to the Canadian context was conducted to better define these impacts and adaptations available to protect health. Drought can impact respiratory health, mental health, illnesses related to exposure to toxins, food/water security, rates of injury and infectious diseases (including food-, water- and vector-borne diseases). A range of direct and indirect adaptation (e.g., agricultural adaptation) options exist to cope with drought. Many have already been employed by public health officials, such as communicable disease monitoring and surveillance and public education and outreach. However, gaps exist in our understanding of the impacts of short-term vs. prolonged drought on the health of Canadians, projections of drought and its characteristics at the regional level and the effectiveness of current adaptations. Further research will be critical to inform adaptation planning to reduce future drought-related risks to health. PMID:26193300

Climate Change, Drought and Human Health in Canada.

PubMed

Yusa, Anna; Berry, Peter; J Cheng, June; Ogden, Nicholas; Bonsal, Barrie; Stewart, Ronald; Waldick, Ruth

2015-07-17

Droughts have been recorded all across Canada and have had significant impacts on individuals and communities. With climate change, projections suggest an increasing risk of drought in Canada, particularly in the south and interior. However, there has been little research on the impacts of drought on human health and the implications of a changing climate. A review of the Canadian, U.S. and international literature relevant to the Canadian context was conducted to better define these impacts and adaptations available to protect health. Drought can impact respiratory health, mental health, illnesses related to exposure to toxins, food/water security, rates of injury and infectious diseases (including food-, water- and vector-borne diseases). A range of direct and indirect adaptation (e.g., agricultural adaptation) options exist to cope with drought. Many have already been employed by public health officials, such as communicable disease monitoring and surveillance and public education and outreach. However, gaps exist in our understanding of the impacts of short-term vs. prolonged drought on the health of Canadians, projections of drought and its characteristics at the regional level and the effectiveness of current adaptations. Further research will be critical to inform adaptation planning to reduce future drought-related risks to health.

Methyl jasmonate-induction of cotton: a field test of the “attract and reward” strategy of conservation biological control

USDA-ARS?s Scientific Manuscript database

Natural or synthetic elicitors can affect plant physiology by stimulating direct and indirect defense responses to herbivores. For example, increased production of plant secondary metabolites, a direct response, can negatively impact herbivore survival, development, and fecundity. Indirect respons...

78 FR 6356 - Notice of Consideration of Approval of Application Regarding Proposed Indirect Transfer of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-30

... NUCLEAR REGULATORY COMMISSION [Docket No. 070-3098; NRC-2011-0081] Notice of Consideration of Approval of Application Regarding Proposed Indirect Transfer of Control of the Construction Authorization for the Mixed Oxide Fuel Fabrication Facility in Aiken, SC; Correction AGENCY: Nuclear Regulatory...

What Does it Really Cost? Allocating Indirect Costs.

ERIC Educational Resources Information Center

Snyder, Herbert; Davenport, Elisabeth

1997-01-01

Better managerial control in terms of decision making and understanding the costs of a system/service result from allocating indirect costs. Allocation requires a three-step process: selecting cost objectives, pooling related overhead costs, and selecting costs bases to connect the objectives to the pooled costs. Argues that activity-based costing…

Genetic and morphological data supporting the hypothesis of adaptive radiation in the endemic fish of Lake Matano.

PubMed

Roy, D; Docker, M F; Hehanussa, P; Heath, D D; Haffner, G D

2004-11-01

Adaptive radiation resulting from differential selection acting on functional features is believed to be an important source of biodiversity. In this study, morphometric measures and mitochondrial DNA are used to test for adaptive radiation within four fish genera (Glossogobius, Oryzias, Dermogenys and Telmatherina) endemic to an ancient island lake (Lake Matano, Sulawesi, Indonesia), using the framework proposed by Schluter (The Ecology of Adaptive Radiation, Oxford University Press, 2000). We demonstrate common ancestry and rapid divergence in one genus (Telmatherina) based on 560 bp of 16S sequence data. We found higher levels of variation in feeding-related traits (N = 8) for Telmatherina relative to the other genera, while no differences were found for sexual display traits (N = 8) or neutral morphological traits (N = 8). Telmatherina also had the highest number of distinct colouration patterns among the four genera. These data, combined with the very low productivity of the lake, are indicative of selection driving adaptive radiation. The morphometric divergence in the Telmatherina likely results from selection acting on feeding traits in this low productivity lake, leading to trophic specialization among closely related morphotypes. These results provide indirect but compelling data supporting the adaptive radiation of Telmatherina in this system.

Sensorimotor adaptation to inertial forces in a multi-force environment does not depend on the number of targets: indirect validation of the altered-proprioception hypothesis.

PubMed

Bourdin, C; Bock, O

2006-11-20

The ability of our sensorimotor system to adapt to changing and complex environmental demands has been under experimental scrutiny for more than a century. Previous works have shown that aimed arm movements adapt quickly and completely to Coriolis force, but incompletely to the combination of Coriolis and centrifugal forces without visual cues. Two hypotheses may be advanced to explain this discrepancy: the workspace-exploration hypothesis, and the degraded-proprioception hypothesis. The aim of this study was to distinguish between the above two alternatives by comparing adaptive improvement during off-axis rotation in subjects pointing at one, three or seven different targets in complete darkness. Two main results emerge: (a) off-axis rotation led initially to errors in the direction of Coriolis force and in the opposite direction of the centrifugal force; (b) the size of the visited workspace has no effect on the way the subjects adapt to a multi-force environment. The lack of a target-number effect and the persistence of lateral errors in the pointing movements performed during rotation of the platform, support the degraded-proprioception rather than the workspace-exploration hypothesis of adaptation to a multi-force environment.

Can Perceptions of Environmental and Climate Change in Island Communities Assist in Adaptation Planning Locally?

PubMed

Aswani, Shankar; Vaccaro, Ismael; Abernethy, Kirsten; Albert, Simon; de Pablo, Javier Fernández-López

2015-12-01

Local perceptions of environmental and climate change, as well as associated adaptations made by local populations, are fundamental for designing comprehensive and inclusive mitigation and adaptation plans both locally and nationally. In this paper, we analyze people's perceptions of environmental and climate-related transformations in communities across the Western Solomon Islands through ethnographic and geospatial methods. Specifically, we documented people's observed changes over the past decades across various environmental domains, and for each change, we asked respondents to identify the causes, timing, and people's adaptive responses. We also incorporated this information into a geographical information system database to produce broad-scale base maps of local perceptions of environmental change. Results suggest that people detected changes that tended to be acute (e.g., water clarity, logging intensity, and agricultural diseases). We inferred from these results that most local observations of and adaptations to change were related to parts of environment/ecosystem that are most directly or indirectly related to harvesting strategies. On the other hand, people were less aware of slower insidious/chronic changes identified by scientific studies. For the Solomon Islands and similar contexts in the insular tropics, a broader anticipatory adaptation planning strategy to climate change should include a mix of local scientific studies and local observations of ongoing ecological changes.

Monitoring Fatigue Status with HRV Measures in Elite Athletes: An Avenue Beyond RMSSD?

PubMed

Schmitt, Laurent; Regnard, Jacques; Millet, Grégoire P

2015-01-01

Among the tools proposed to assess the athlete's "fatigue," the analysis of heart rate variability (HRV) provides an indirect evaluation of the settings of autonomic control of heart activity. HRV analysis is performed through assessment of time-domain indices, the square root of the mean of the sum of the squares of differences between adjacent normal R-R intervals (RMSSD) measured during short (5 min) recordings in supine position upon awakening in the morning and particularly the logarithm of RMSSD (LnRMSSD) has been proposed as the most useful resting HRV indicator. However, if RMSSD can help the practitioner to identify a global "fatigue" level, it does not allow discriminating different types of fatigue. Recent results using spectral HRV analysis highlighted firstly that HRV profiles assessed in supine and standing positions are independent and complementary; and secondly that using these postural profiles allows the clustering of distinct sub-categories of "fatigue." Since, cardiovascular control settings are different in standing and lying posture, using the HRV figures of both postures to cluster fatigue state embeds information on the dynamics of control responses. Such, HRV spectral analysis appears more sensitive and enlightening than time-domain HRV indices. The wealthier information provided by this spectral analysis should improve the monitoring of the adaptive training-recovery process in athletes.

Possible origins of consciousness in simple control over "involuntary" neuroimmunological action.

PubMed

Clark, Kevin B

2018-05-01

The origin(s) and purpose(s) of consciousness continue to be fervently debated by neuroscientists. A recent unconventional hypothesis put forth by Morsella et al. suggests the primary function of consciousness is the integration, selection, and execution of advantageous lower-level voluntary skeletal muscle behavior on surrounding external environments. However, at main issue is whether more precise, adaptable voluntary skeletal motor action, and therefore the corresponding workings of consciousness, first emerged and evolved in animals to exert control over external environments or internal ones regulated by less flexible autonomic function. Using the example of voluntary immunomodulation, one can identify the strengths and weaknesses of either rationale. For instance, highly trained meditative techniques for immunomodulation more-or-less conform to Morsella et al.'s assumptions on higher-level indirect conscious control of autonomic function. Whereas, untrained skeletal motor resolution of infection-related approach-avoidance conflicts support conclusions contrary to those of Morsella et al. In such cases, primitive voluntary changes in host respiration rate and volume may selectively facilitate/inhibit acute autonomic psychophysiological stress responses to pathogen insult. This and other types of scenarios predictably give evolutionary and ecological rise to self-awareness of (visceral) internal states as well as to voluntary regulation of internal state action conflicts. Copyright © 2018 Elsevier Inc. All rights reserved.

In-process and post-process measurements of drill wear for control of the drilling process

NASA Astrophysics Data System (ADS)

Liu, Tien-I.; Liu, George; Gao, Zhiyu

2011-12-01

Optical inspection was used in this research for the post-process measurements of drill wear. A precision toolmakers" microscope was used. Indirect index, cutting force, is used for in-process drill wear measurements. Using in-process measurements to estimate the drill wear for control purpose can decrease the operation cost and enhance the product quality and safety. The challenge is to correlate the in-process cutting force measurements with the post-process optical inspection of drill wear. To find the most important feature, the energy principle was used in this research. It is necessary to select only the cutting force feature which shows the highest sensitivity to drill wear. The best feature selected is the peak of torque in the drilling process. Neuro-fuzzy systems were used for correlation purposes. The Adaptive-Network-Based Fuzzy Inference System (ANFIS) can construct fuzzy rules with membership functions to generate an input-output pair. A 1x6 ANFIS architecture with product of sigmoid membership functions can in-process measure the drill wear with an error as low as 0.15%. This is extremely important for control of the drilling process. Furthermore, the measurement of drill wear was performed under different drilling conditions. This shows that ANFIS has the capability of generalization.

Direct and Indirect Effects of PM on the Cardiovascular System

PubMed Central

Nelin, Timothy D.; Joseph, Allan M.; Gorr, Matthew W.; Wold, Loren E.

2011-01-01

Human exposure to particulate matter (PM) elicits a variety of responses on the cardiovascular system through both direct and indirect pathways. Indirect effects of PM on the cardiovascular system are mediated through the autonomic nervous system, which controls heart rate variability, and inflammatory responses, which augment acute cardiovascular events and atherosclerosis. Recent research demonstrates that PM also affects the cardiovascular system directly by entry into the systemic circulation. This process causes myocardial dysfunction through mechanisms of reactive oxygen species production, calcium ion interference, and vascular dysfunction. In this review, we will present key evidence in both the direct and indirect pathways, suggest clinical applications of the current literature, and recommend directions for future research. PMID:22119171

INDIRECT EFFECT OF X-RADIATION ON BONE GROWTH IN RATS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conard, R.A.

1962-12-21

Effects of 200 to 600 r of x irradiation on tibial bone growth in groups of weanling male rats were studied by in vivo measurement of tibial bone growth in serial radiographs. By comparison of growth rates in shielded with unshielded legs, direct and indirect effects of radiation were demonstrated, both roughly dose dependent, but with the indirect effect being about twice that of the direct effect. Pair-feeding experiments showed that about 70% of the indirect effect was due to radiation-induced lowered food consumption. By partial-body shielding experiments, using pnir-fed controls, it was shown that the abdomen may be themore » site of a non-nutritional abscopal effect. (auth)« less

A Model Framework to Estimate Impact and Cost of Genetics-Based Sterile Insect Methods for Dengue Vector Control

PubMed Central

Alphey, Nina; Alphey, Luke; Bonsall, Michael B.

2011-01-01

Vector-borne diseases impose enormous health and economic burdens and additional methods to control vector populations are clearly needed. The Sterile Insect Technique (SIT) has been successful against agricultural pests, but is not in large-scale use for suppressing or eliminating mosquito populations. Genetic RIDL technology (Release of Insects carrying a Dominant Lethal) is a proposed modification that involves releasing insects that are homozygous for a repressible dominant lethal genetic construct rather than being sterilized by irradiation, and could potentially overcome some technical difficulties with the conventional SIT technology. Using the arboviral disease dengue as an example, we combine vector population dynamics and epidemiological models to explore the effect of a program of RIDL releases on disease transmission. We use these to derive a preliminary estimate of the potential cost-effectiveness of vector control by applying estimates of the costs of SIT. We predict that this genetic control strategy could eliminate dengue rapidly from a human community, and at lower expense (approximately US$ 2∼30 per case averted) than the direct and indirect costs of disease (mean US$ 86–190 per case of dengue). The theoretical framework has wider potential use; by appropriately adapting or replacing each component of the framework (entomological, epidemiological, vector control bio-economics and health economics), it could be applied to other vector-borne diseases or vector control strategies and extended to include other health interventions. PMID:21998654

An Adaptive Supervisory Sliding Fuzzy Cerebellar Model Articulation Controller for Sensorless Vector-Controlled Induction Motor Drive Systems

PubMed Central

Wang, Shun-Yuan; Tseng, Chwan-Lu; Lin, Shou-Chuang; Chiu, Chun-Jung; Chou, Jen-Hsiang

2015-01-01

This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC) in the speed sensorless vector control of an induction motor (IM) drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes—the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC—were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE) was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes. PMID:25815450

An adaptive supervisory sliding fuzzy cerebellar model articulation controller for sensorless vector-controlled induction motor drive systems.

PubMed

Wang, Shun-Yuan; Tseng, Chwan-Lu; Lin, Shou-Chuang; Chiu, Chun-Jung; Chou, Jen-Hsiang

2015-03-25

This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC) in the speed sensorless vector control of an induction motor (IM) drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes--the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC--were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE) was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes.

Adaptive Control Using Residual Mode Filters Applied to Wind Turbines

NASA Technical Reports Server (NTRS)

Frost, Susan A.; Balas, Mark J.

2011-01-01

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

Adaptive Control Allocation in the Presence of Actuator Failures

NASA Technical Reports Server (NTRS)

Liu, Yu; Crespo, Luis G.

2010-01-01

In this paper, a novel adaptive control allocation framework is proposed. In the adaptive control allocation structure, cooperative actuators are grouped and treated as an equivalent control effector. A state feedback adaptive control signal is designed for the equivalent effector and allocated to the member actuators adaptively. Two adaptive control allocation algorithms are proposed, which guarantee closed-loop stability and asymptotic state tracking in the presence of uncertain loss of effectiveness and constant-magnitude actuator failures. The proposed algorithms can be shown to reduce the controller complexity with proper grouping of the actuators. The proposed adaptive control allocation schemes are applied to two linearized aircraft models, and the simulation results demonstrate the performance of the proposed algorithms.

Neural network based adaptive control for nonlinear dynamic regimes

NASA Astrophysics Data System (ADS)

Shin, Yoonghyun

Adaptive control designs using neural networks (NNs) based on dynamic inversion are investigated for aerospace vehicles which are operated at highly nonlinear dynamic regimes. NNs play a key role as the principal element of adaptation to approximately cancel the effect of inversion error, which subsequently improves robustness to parametric uncertainty and unmodeled dynamics in nonlinear regimes. An adaptive control scheme previously named 'composite model reference adaptive control' is further developed so that it can be applied to multi-input multi-output output feedback dynamic inversion. It can have adaptive elements in both the dynamic compensator (linear controller) part and/or in the conventional adaptive controller part, also utilizing state estimation information for NN adaptation. This methodology has more flexibility and thus hopefully greater potential than conventional adaptive designs for adaptive flight control in highly nonlinear flight regimes. The stability of the control system is proved through Lyapunov theorems, and validated with simulations. The control designs in this thesis also include the use of 'pseudo-control hedging' techniques which are introduced to prevent the NNs from attempting to adapt to various actuation nonlinearities such as actuator position and rate saturations. Control allocation is introduced for the case of redundant control effectors including thrust vectoring nozzles. A thorough comparison study of conventional and NN-based adaptive designs for a system under a limit cycle, wing-rock, is included in this research, and the NN-based adaptive control designs demonstrate their performances for two highly maneuverable aerial vehicles, NASA F-15 ACTIVE and FQM-117B unmanned aerial vehicle (UAV), operated under various nonlinearities and uncertainties.

Development of Real Time Implementation of 5/5 Rule based Fuzzy Logic Controller Shunt Active Power Filter for Power Quality Improvement

NASA Astrophysics Data System (ADS)

Puhan, Pratap Sekhar; Ray, Pravat Kumar; Panda, Gayadhar

2016-12-01

This paper presents the effectiveness of 5/5 Fuzzy rule implementation in Fuzzy Logic Controller conjunction with indirect control technique to enhance the power quality in single phase system, An indirect current controller in conjunction with Fuzzy Logic Controller is applied to the proposed shunt active power filter to estimate the peak reference current and capacitor voltage. Current Controller based pulse width modulation (CCPWM) is used to generate the switching signals of voltage source inverter. Various simulation results are presented to verify the good behaviour of the Shunt active Power Filter (SAPF) with proposed two levels Hysteresis Current Controller (HCC). For verification of Shunt Active Power Filter in real time, the proposed control algorithm has been implemented in laboratory developed setup in dSPACE platform.

Real-time performance assessment and adaptive control for a water chiller unit in an HVAC system

NASA Astrophysics Data System (ADS)

Bai, Jianbo; Li, Yang; Chen, Jianhao

2018-02-01

The paper proposes an adaptive control method for a water chiller unit in a HVAC system. Based on the minimum variance evaluation, the adaptive control method was used to realize better control of the water chiller unit. To verify the performance of the adaptive control method, the proposed method was compared with an a conventional PID controller, the simulation results showed that adaptive control method had superior control performance to that of the conventional PID controller.

Assessing climate change risks to the natural environment to facilitate cross-sectoral adaptation policy.

PubMed

Brown, Iain

2018-06-13

Climate change policy requires prioritization of adaptation actions across many diverse issues. The policy agenda for the natural environment includes not only biodiversity, soils and water, but also associated human benefits through agriculture, forestry, water resources, hazard alleviation, climate regulation and amenity value. To address this broad agenda, the use of comparative risk assessment is investigated with reference to statutory requirements of the UK Climate Change Risk Assessment. Risk prioritization was defined by current adaptation progress relative to risk magnitude and implementation lead times. Use of an ecosystem approach provided insights into risk interactions, but challenges remain in quantifying ecosystem services. For all risks, indirect effects and potential systemic risks were identified from land-use change, responding to both climate and socio-economic drivers, and causing increased competition for land and water resources. Adaptation strategies enhancing natural ecosystem resilience can buffer risks and sustain ecosystem services but require improved cross-sectoral coordination and recognition of dynamic change. To facilitate this, risk assessments need to be reflexive and explicitly assess decision outcomes contingent on their riskiness and adaptability, including required levels of human intervention, influence of uncertainty and ethical dimensions. More national-scale information is also required on adaptation occurring in practice and its efficacy in moderating risks.This article is part of the theme issue 'Advances in risk assessment for climate change adaptation policy'. © 2018 The Author(s).

Assessing climate change risks to the natural environment to facilitate cross-sectoral adaptation policy

NASA Astrophysics Data System (ADS)

Brown, Iain

2018-06-01

Climate change policy requires prioritization of adaptation actions across many diverse issues. The policy agenda for the natural environment includes not only biodiversity, soils and water, but also associated human benefits through agriculture, forestry, water resources, hazard alleviation, climate regulation and amenity value. To address this broad agenda, the use of comparative risk assessment is investigated with reference to statutory requirements of the UK Climate Change Risk Assessment. Risk prioritization was defined by current adaptation progress relative to risk magnitude and implementation lead times. Use of an ecosystem approach provided insights into risk interactions, but challenges remain in quantifying ecosystem services. For all risks, indirect effects and potential systemic risks were identified from land-use change, responding to both climate and socio-economic drivers, and causing increased competition for land and water resources. Adaptation strategies enhancing natural ecosystem resilience can buffer risks and sustain ecosystem services but require improved cross-sectoral coordination and recognition of dynamic change. To facilitate this, risk assessments need to be reflexive and explicitly assess decision outcomes contingent on their riskiness and adaptability, including required levels of human intervention, influence of uncertainty and ethical dimensions. More national-scale information is also required on adaptation occurring in practice and its efficacy in moderating risks. This article is part of the theme issue `Advances in risk assessment for climate change adaptation policy'.

Gene expression changes in the coccolithophore Emiliania huxleyi after 500 generations of selection to ocean acidification.

PubMed

Lohbeck, Kai T; Riebesell, Ulf; Reusch, Thorsten B H

2014-07-07

Coccolithophores are unicellular marine algae that produce biogenic calcite scales and substantially contribute to marine primary production and carbon export to the deep ocean. Ongoing ocean acidification particularly impairs calcifying organisms, mostly resulting in decreased growth and calcification. Recent studies revealed that the immediate physiological response in the coccolithophore Emiliania huxleyi to ocean acidification may be partially compensated by evolutionary adaptation, yet the underlying molecular mechanisms are currently unknown. Here, we report on the expression levels of 10 candidate genes putatively relevant to pH regulation, carbon transport, calcification and photosynthesis in E. huxleyi populations short-term exposed to ocean acidification conditions after acclimation (physiological response) and after 500 generations of high CO2 adaptation (adaptive response). The physiological response revealed downregulation of candidate genes, well reflecting the concomitant decrease of growth and calcification. In the adaptive response, putative pH regulation and carbon transport genes were up-regulated, matching partial restoration of growth and calcification in high CO2-adapted populations. Adaptation to ocean acidification in E. huxleyi likely involved improved cellular pH regulation, presumably indirectly affecting calcification. Adaptive evolution may thus have the potential to partially restore cellular pH regulatory capacity and thereby mitigate adverse effects of ocean acidification. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Workforce Issues of the 21st Century: The People CMM to the Rescue

DTIC Science & Technology

2008-07-01

skilled, and adaptable workforce United States, European Union, Mexico, South Africa, China… Work - life balance United States, European Union, China...direction Seek work / life balance Generation Y 1980 - 2000 Prefer informality Learn quickly Embrace diversity Requires supervision Indirect...communication: email & texting Seek “demand” work / life balance Source: Hammill 2005 Traditionalist 1928-1945 Hard worker Respects authority Work is an

Fear of Hypoglycemia, Parenting Stress, and Metabolic Control for Children with Type 1 Diabetes and Their Parents.

PubMed

Viaene, Ann-Sofie; Van Daele, Tom; Bleys, Dries; Faust, Kelly; Massa, Guy G

2017-03-01

This study sets out to extend current knowledge of parenting stress and fear of hypoglycemia (FoH) in parents of children with type 1 diabetes mellitus (T1DM). We examined if the relationship between parental and children's FoH and metabolic control, as reflected by HbA1c, is mediated by parenting stress. A total of 63 parents and children with T1DM were recruited during their routine physician's appointment. Parents completed questionnaires on parenting stress and FoH. Children eight years and older also completed a questionnaire on FoH. HbA1c values were obtained from all children. Mediation analysis revealed an indirect association between parental FoH and HbA1c values through parenting stress (Sobel's z = 2.42, p = .02), but no indirect association between children's FoH and HbA1c. We concluded that parental FOH has an indirect association with the child's metabolic control that is mediated by parenting stress. More simply, fear of hypoglycemia predicts parent stress, which in turn, predicts metabolic control.

VAGINAL PROGESTERONE VERSUS CERVICAL CERCLAGE FOR THE PREVENTION OF PRETERM BIRTH IN WOMEN WITH A SONOGRAPHIC SHORT CERVIX, SINGLETON GESTATION, AND PREVIOUS PRETERM BIRTH: A SYSTEMATIC REVIEW AND INDIRECT COMPARISON META-ANALYSIS

PubMed Central

CONDE-AGUDELO, Agustin; ROMERO, Roberto; NICOLAIDES, Kypros; CHAIWORAPONGSA, Tinnakorn; O'BRIEN, John M.; CETINGOZ, Elcin; DA FONSECA, Eduardo; CREASY, George; SOMA-PILLAY, Priya; FUSEY, Shalini; CAM, Cetin; ALFIREVIC, Zarko; HASSAN, Sonia S.

2012-01-01

OBJECTIVE No randomized controlled trial has directly compared vaginal progesterone and cervical cerclage for the prevention of preterm birth in women with a sonographic short cervix in the midtrimester, singleton gestation, and previous spontaneous preterm birth. We performed an indirect comparison of vaginal progesterone versus cerclage, using placebo/no cerclage as the common comparator. STUDY DESIGN Adjusted indirect meta-analysis of randomized controlled trials. RESULTS Four studies evaluating vaginal progesterone versus placebo (158 patients) and five evaluating cerclage versus no cerclage (504 patients) were included. Both interventions were associated with a statistically significant reduction in the risk of preterm birth <32 weeks of gestation and composite perinatal morbidity and mortality compared with placebo/no cerclage. Adjusted indirect meta-analyses did not show statistically significant differences between vaginal progesterone and cerclage in reducing preterm birth or adverse perinatal outcomes. CONCLUSION Based on state-of-the-art methodology for indirect comparisons, either vaginal progesterone or cerclage are equally efficacious in the prevention of preterm birth in women with a sonographic short cervix in the midtrimester, singleton gestation, and previous preterm birth. The selection of the optimal treatment may depend upon adverse events, cost and patient/clinician preferences. PMID:23157855

Adjustment of Adaptive Gain with Bounded Linear Stability Analysis to Improve Time-Delay Margin for Metrics-Driven Adaptive Control

NASA Technical Reports Server (NTRS)

Bakhtiari-Nejad, Maryam; Nguyen, Nhan T.; Krishnakumar, Kalmanje Srinvas

2009-01-01

This paper presents the application of Bounded Linear Stability Analysis (BLSA) method for metrics driven adaptive control. The bounded linear stability analysis method is used for analyzing stability of adaptive control models, without linearizing the adaptive laws. Metrics-driven adaptive control introduces a notion that adaptation should be driven by some stability metrics to achieve robustness. By the application of bounded linear stability analysis method the adaptive gain is adjusted during the adaptation in order to meet certain phase margin requirements. Analysis of metrics-driven adaptive control is evaluated for a linear damaged twin-engine generic transport model of aircraft. The analysis shows that the system with the adjusted adaptive gain becomes more robust to unmodeled dynamics or time delay.

To twist or poke? A method for identifying usability issues with the rotary controller and touch screen for control of in-vehicle information systems.

PubMed

Harvey, Catherine; Stanton, Neville A; Pickering, Carl A; McDonald, Mike; Zheng, Pengjun

2011-07-01

In-vehicle information systems (IVIS) can be controlled by the user via direct or indirect input devices. In order to develop the next generation of usable IVIS, designers need to be able to evaluate and understand the usability issues associated with these two input types. The aim of this study was to investigate the effectiveness of a set of empirical usability evaluation methods for identifying important usability issues and distinguishing between the IVIS input devices. A number of usability issues were identified and their causal factors have been explored. These were related to the input type, the structure of the menu/tasks and hardware issues. In particular, the translation between inputs and on-screen actions and a lack of visual feedback for menu navigation resulted in lower levels of usability for the indirect device. This information will be useful in informing the design of new IVIS, with improved usability. STATEMENT OF RELEVANCE: This paper examines the use of empirical methods for distinguishing between direct and indirect IVIS input devices and identifying usability issues. Results have shown that the characteristics of indirect input devices produce more serious usability issues, compared with direct devices and can have a negative effect on the driver-vehicle interaction.

Resting and exercise energy metabolism in weight-reduced adults with severe obesity.

PubMed

Hames, Kazanna C; Coen, Paul M; King, Wendy C; Anthony, Steven J; Stefanovic-Racic, Maja; Toledo, Frederico G S; Lowery, Jolene B; Helbling, Nicole L; Dubé, John J; DeLany, James P; Jakicic, John M; Goodpaster, Bret H

2016-06-01

To determine effects of physical activity (PA) with diet-induced weight loss on energy metabolism in adults with severe obesity. Adults with severe obesity (n = 11) were studied across 6 months of intervention, then compared with controls with less severe obesity (n = 7) or normal weight (n = 9). Indirect calorimetry measured energy metabolism during exercise and rest. Markers of muscle oxidation were determined by immunohistochemistry. Data were presented as medians. The intervention induced 7% weight loss (P = 0.001) and increased vigorous PA by 24 min/wk (P = 0.02). During exercise, energy expenditure decreased, efficiency increased (P ≤ 0.03), and fatty acid oxidation (FAO) did not change. Succinate dehydrogenase increased (P = 0.001), but fiber type remained the same. Post-intervention subjects' resting metabolism remained similar to controls. Efficiency was lower in post-intervention subjects compared with normal-weight controls exercising at 25 W (P ≤ 0.002) and compared with all controls exercising at 60% VO2peak (P ≤ 0.019). Resting and exercise FAO of post-intervention subjects remained similar to adults with less severe obesity. Succinate dehydrogenase and fiber type were similar across all body weight statuses. While metabolic adaptations to PA during weight loss occur in adults with severe obesity, FAO does not change. Resulting FAO during rest and exercise remains similar to adults with less severe obesity. © 2016 The Obesity Society.

Perceived parental monitoring and adolescent internet addiction: A moderated mediation model.

PubMed

Ding, Qingwen; Li, Dongping; Zhou, Yueyue; Dong, Hongning; Luo, Jinjing

2017-11-01

Bronfenbrenner's (1979) ecological model focuses on the interrelation between different contexts and the interaction between individuals and their proximal contexts. Based on this theory, the present study tested a moderated mediation model of family, peer, and individual characteristics to investigate how they impact adolescent Internet addiction. Specifically, we examined whether deviant peer affiliation partially mediated the relation between perceived parental monitoring and adolescent Internet addiction, and whether this indirect relation was moderated by effortful control. A total of 747 Chinese middle school students filled out anonymous questionnaires concerning perceived parental monitoring, deviant peer affiliation, effortful control, and Internet addiction. The findings indicated that while the impact of parental monitoring on Internet addiction was partially mediated by deviant peer affiliation, effortful control moderated the first stage of the indirect relationship. For low effortful control adolescents, perceived parental monitoring negatively predicted deviant peer affiliation. Conversely, the indirect path was not significant for high effortful control adolescents. These findings highlight the need to consider family, peer and individual factors simultaneously when evaluating risks associated with adolescent Internet addiction and have important implications for the prevention and intervention of adolescent Internet addiction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tool to assess causality of direct and indirect adverse events associated with therapeutic interventions.

PubMed

Zorzela, Liliane; Mior, Silvano; Boon, Heather; Gross, Anita; Yager, Jeromy; Carter, Rose; Vohra, Sunita

2018-03-01

To develop and test a tool to assess the causality of direct and indirect adverse events associated with therapeutic interventions. The intervention was one or more drugs and/or natural health products, a device, or practice (professional delivering the intervention). Through the assessment of causality of adverse events, we can learn about factors contributing to the harm and consider what modification may prevent its reoccurrence. Existing scales (WHO-UMC, Naranjo and Horn) were adapted to develop a tool (algorithm and table) to evaluate cases of serious harmful events reported through a national surveillance study. We also incorporated a novel approach that assesses indirect harm (caused by the delay in diagnosis/treatment) and the health provider delivering the intervention (practice). The tool was tested, revised and then implemented to assess all reported cases of serious events resulting from use of complementary therapies. The use of complementary therapies was the trigger to report the event. Each case was evaluated by two assessors, out of a panel of five, representing different health care professionals. The tool was used in assessment of eight serious adverse events. Each event was independently evaluated by two assessors. The algorithm facilitated assessment of a serious direct or indirect harm. Assessors agreed in the final score on seven of eight cases (weighted kappa coefficient of 0.75). A tool to support the assessment of causality of adverse events was developed and tested. We propose a novel method to assess direct and indirect harms related to product(s), device(s), practice or a combination of the previous. Further research will probably help evaluate this approach across different settings and interventions.

Clinical Evaluation of Indirect Particle-Filled Composite Resin CAD/CAM Partial Crowns after 24 Months.

PubMed

Zimmermann, Moritz; Koller, Christina; Reymus, Marcel; Mehl, Albert; Hickel, Reinhard

2017-04-19

Resin-based CAD/CAM compound materials might be promising for single-tooth restorations. Insufficient clinical data are available for this new material class. The purpose of this study was to describe initial clinical in vivo results for indirect particle-filled composite resin CAD/CAM restorations after 24 months. Indirect particle-filled composite resin restorations were fabricated with a CAD/CAM method (CEREC Bluecam intraoral scanner, CEREC MCXL milling unit) by calibrated dental students. Forty-two partial crown restorations were seated adhesively in 30 patients with caries lesions or insufficient restorations (baseline). Strict inclusion criteria were defined for the patient collective. Follow-up evaluation comprised 40 restorations after 12 months and 33 restorations after 24 months. Evaluation criteria were modified FDI criteria with grades (1) to (5). Rating with FDI criteria (5) was defined as clinical failure. Statistical analysis was performed with Wilcoxon-Test (p < 0.05). The success rate of indirect particle-filled composite resin CAD/CAM restorations after 12 months was 95.0% with two debondings observed. The cumulative success rate for indirect particle-filled composite resin CAD/CAM restorations after 24 months was 85.7% with two tooth fractures and one debonding. Statistically significant differences were found for baseline and 24-month follow-up evaluation for anatomic form and marginal adaptation criterion examined in respect to FDI criteria guidelines (Wilcoxon-Test, p < 0.05). This study demonstrates particle-filled composite resin CAD/CAM restorations having a clinical success rate of 85.7% after 24 months. Adhesive bonding procedures need to be ensured carefully. A longer clinical evaluation period is necessary to draw further conclusions. © 2017 by the American College of Prosthodontists.

Intracranial EEG correlates of implicit relational inference within the hippocampus.

PubMed

Reber, T P; Do Lam, A T A; Axmacher, N; Elger, C E; Helmstaedter, C; Henke, K; Fell, J

2016-01-01

Drawing inferences from past experiences enables adaptive behavior in future situations. Inference has been shown to depend on hippocampal processes. Usually, inference is considered a deliberate and effortful mental act which happens during retrieval, and requires the focus of our awareness. Recent fMRI studies hint at the possibility that some forms of hippocampus-dependent inference can also occur during encoding and possibly also outside of awareness. Here, we sought to further explore the feasibility of hippocampal implicit inference, and specifically address the temporal evolution of implicit inference using intracranial EEG. Presurgical epilepsy patients with hippocampal depth electrodes viewed a sequence of word pairs, and judged the semantic fit between two words in each pair. Some of the word pairs entailed a common word (e.g., "winter-red," "red-cat") such that an indirect relation was established in following word pairs (e.g., "winter-cat"). The behavioral results suggested that drawing inference implicitly from past experience is feasible because indirect relations seemed to foster "fit" judgments while the absence of indirect relations fostered "do not fit" judgments, even though the participants were unaware of the indirect relations. A event-related potential (ERP) difference emerging 400 ms post-stimulus was evident in the hippocampus during encoding, suggesting that indirect relations were already established automatically during encoding of the overlapping word pairs. Further ERP differences emerged later post-stimulus (1,500 ms), were modulated by the participants' responses and were evident during encoding and test. Furthermore, response-locked ERP effects were evident at test. These ERP effects could hence be a correlate of the interaction of implicit memory with decision-making. Together, the data map out a time-course in which the hippocampus automatically integrates memories from discrete but related episodes to implicitly influence future decision making. © 2015 Wiley Periodicals, Inc.

Beyond promiscuity: mate-choice commitments in social breeding

PubMed Central

Boomsma, Jacobus J.

2013-01-01

Obligate eusociality with distinct caste phenotypes has evolved from strictly monogamous sub-social ancestors in ants, some bees, some wasps and some termites. This implies that no lineage reached the most advanced form of social breeding, unless helpers at the nest gained indirect fitness values via siblings that were identical to direct fitness via offspring. The complete lack of re-mating promiscuity equalizes sex-specific variances in reproductive success. Later, evolutionary developments towards multiple queen-mating retained lifetime commitment between sexual partners, but reduced male variance in reproductive success relative to female's, similar to the most advanced vertebrate cooperative breeders. Here, I (i) discuss some of the unique and highly peculiar mating system adaptations of eusocial insects; (ii) address ambiguities that remained after earlier reviews and extend the monogamy logic to the evolution of soldier castes; (iii) evaluate the evidence for indirect fitness benefits driving the dynamics of (in)vertebrate cooperative breeding, while emphasizing the fundamental differences between obligate eusociality and cooperative breeding; (iv) infer that lifetime commitment is a major driver towards higher levels of organization in bodies, colonies and mutualisms. I argue that evolutionary informative definitions of social systems that separate direct and indirect fitness benefits facilitate transparency when testing inclusive fitness theory. PMID:23339241

Indirect Identification of Linear Stochastic Systems with Known Feedback Dynamics

NASA Technical Reports Server (NTRS)

Huang, Jen-Kuang; Hsiao, Min-Hung; Cox, David E.

1996-01-01

An algorithm is presented for identifying a state-space model of linear stochastic systems operating under known feedback controller. In this algorithm, only the reference input and output of closed-loop data are required. No feedback signal needs to be recorded. The overall closed-loop system dynamics is first identified. Then a recursive formulation is derived to compute the open-loop plant dynamics from the identified closed-loop system dynamics and known feedback controller dynamics. The controller can be a dynamic or constant-gain full-state feedback controller. Numerical simulations and test data of a highly unstable large-gap magnetic suspension system are presented to demonstrate the feasibility of this indirect identification method.

Direct and indirect links between parenting styles, self-concealment (secrets), impaired control over drinking and alcohol-related outcomes.

PubMed

Hartman, Jessica D; Patock-Peckham, Julie A; Corbin, William R; Gates, Jonathan R; Leeman, Robert F; Luk, Jeremy W; King, Kevin M

2015-01-01

Self-concealment reflects uncomfortable feelings, thoughts, and information people have about themselves that they avoid telling others (Larson & Chastain, 1990). According to Larson and Chastain (1990) these secrets range from the slightly embarrassing to the very distressing with an individual's most traumatic experiences often concealed. Parental attitudes including those involving self-disclosure are thought to be expressed in their choice of parenting style (Brand, Hatzinger, Beck, & Holsboer-Trachsler, 2009). The specific aim of this investigation was to examine the direct and indirect influences of parenting styles on self-concealment, impaired control over drinking (i.e. the inability to stop drinking when intended), alcohol use (quantity/frequency), and alcohol-related problems. A structural equation model with 419 (223 men, 196 women) university students was examined. Two and three path mediated effects were examined with the bias corrected bootstrap technique in Mplus. Having an authoritarian mother was directly linked to more self-concealment, while having an authoritative father was directly linked to less self-concealment. Higher levels of mother authoritarianism were indirectly linked to both increased alcohol use and alcohol-related problems through more self-concealment and more impaired control over drinking. Moreover, higher levels of father authoritativeness were indirectly linked to less alcohol use and alcohol-related problems through less self-concealment and less impaired control over drinking. These findings suggest that parenting styles influence vulnerabilities such as self-concealment in the impaired control over the drinking pathway to alcohol use and alcohol-related problems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Direct and indirect costs among employees with diabetic retinopathy in the United States.

PubMed

Lee, Lauren J; Yu, Andrew P; Cahill, Kevin E; Oglesby, Alan K; Tang, Jackson; Qiu, Ying; Birnbaum, Howard G

2008-05-01

To examine, from the employer perspective, the direct (healthcare) and indirect (workloss) costs of employees with diabetic retinopathy (DR) compared to control non-DR employees with diabetes, and within DR subgroups. Compared annual costs using claims data from 17 large companies (1999-2004). 'DR employees' (n = 2098) had >or= 1 DR (International Classification of Disease, 9th Revision [ICD-9]) diagnosis; DR subgroups included employees with diabetic macular edema (DME), proliferative DR (PDR), and employees receiving photocoagulation or vitrectomy procedures. Descriptive and multivariate tests were performed. DR employee annual direct costs were $18,218 (indirect = $3548) compared to $11,898 (indirect = $2374) for controls (Delta = $2032 (adjusted); p < 0.0001). Costs differences were larger across DR employee subgroups: DME/non-DME ($28,606/$16,363); PDR/non-PDR ($30,135/$13,445; p < 0.0001); DR with/without photocoagulation ($34,539/$16,041; p < 0.0001); and DR with/without vitrectomy ($63,933/$17,239; p < 0.0001). This study examined the incremental costs of treating DR employees, which may be higher than the incremental costs of DR itself. Some measures of diabetes severity (e.g., duration of diabetes) were not available in the claims data, and were therefore not included in the multivariate models. The cost of photocoagulation and vitrectomy procedures pertain to individuals who underwent these procedures, and not the cost of the procedures themselves. DR employees had significantly higher costs than controls, and larger differences existed within DR subgroups. Indirect costs accounted for about 20% of total cost.

Impact of Mother-Daughter Relationship on Hypertension Self-management and Quality of Life: Testing Dyadic Dynamics Using the Actor-Partner Interdependence Model.

PubMed

Shawler, Celeste; Edward, Jean; Ling, Jiying; Crawford, Tim N; Rayens, Mary Kay

Although hypertension (HTN) treatment rates are similar across age groups of women, effective control is significantly worse among older women. Only 20% of hypertensive women aged 70 to 79 years have controlled blood pressure. The purpose of this longitudinal study was to test the effects of the quality of mother-daughter relationship, inner strength, and control on HTN self-management and health-related quality of life (HRQOL) for both members of the dyad at 6 months. The Actor-Partner Interdependence Model was used to examine the direct ("actor") and indirect ("partner") effects of 46 dyads. The mothers' perceived relationship quality with daughters directly impacted their own self-management of HTN and HRQOL while also indirectly affecting their daughters' self-management. Similarly, the daughters' perceived strength of their relationship with their mothers directly influenced their self-management and HRQOL and indirectly affected their mothers' self-management and HRQOL.

Adiposity has no direct effect on carotid intima-media thickness in adolescents and young adults: Use of structural equation modeling to elucidate indirect & direct pathways.

PubMed

Gao, Zhiqian; Khoury, Philip R; McCoy, Connie E; Shah, Amy S; Kimball, Thomas R; Dolan, Lawrence M; Urbina, Elaine M

2016-03-01

Carotid intima-media thickness (cIMT) is associated with CV events in adults. Thicker cIMT is found in youth with CV risk factors including obesity. Which risk factors have the most effect upon cIMT in youth and whether obesity has direct or indirect effects is not known. We used structural equation modeling to elucidate direct and indirect pathways through which obesity and other risk factors were associated with cIMT. We collected demographics, anthropometrics and laboratory data on 784 subjects age 10-24 years (mean 18.0 ± 3.3 years). Common, bulb and internal carotid cIMT were measured by ultrasound. Multivariable regression analysis was performed to assess independent determinants of cIMT. Analyses were repeated with structural equation modeling to determine direct and indirect effects. Multivariable regression models explained 11%-22% of variation of cIMT. Age, sex and systolic blood pressure (BP) z-score were significant determinants of all cIMT segments. Body mass index (BMI) z-score, race, presence of type 2 diabetes mellitus (T2DM), hemoglobin A1c (HbA1c) and non-HDL were significant for some segments (all p = 0.05). The largest direct effect on cIMT was age (0.312) followed by BP (0.228), Blood glucose control (0.108) and non-HDL (0.134). BMI only had a significant indirect effect through blood glucose control, BP & non-HDL. High sensitivity C-reactive protein (CRP) had a small indirect effect through blood glucose control (all p = 0.05). Age and BP are the major factors with direct effect on cIMT. Glucose and non-HDL were also important in this cohort with a high prevalence of T2DM. BMI only has indirect effects, through other risk factors. Traditional CV risk factors have important direct effects on cIMT in the young, but adiposity exerts its influence only through other CV risk factors. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Forest ecosystems: Vegetation, disturbance, and economics: Chapter 5

USGS Publications Warehouse

Littell, Jeremy S.; Hicke, Jeffrey A.; Shafer, Sarah L.; Capalbo, Susan M.; Houston, Laurie L.; Glick, Patty

2013-01-01

Forests cover about 47% of the Northwest (NW–Washington, Oregon, and Idaho) (Smith et al. 2009, fig. 5.1, table 5.1). The impacts of current and future climate change on NW forest ecosystems are a product of the sensitivities of ecosystem processes to climate and the degree to which humans depend on and interact with those systems. Forest ecosystem structure and function, particularly in relatively unmanaged forests where timber harvest and other land use have smaller effects, is sensitive to climate change because climate has a strong influence on ecosystem processes. Climate can affect forest structure directly through its control of plan physiology and life history (establishment, individual growth, productivity, and morality) or indirectly through its control of disturbance (fire, insects, disease). As climate changes, many forest processes will be affected, altering ecosystem services such as timber production and recreation. These changes have socioeconomic implications (e.g. for timber economies) and will require changes to current management of forests. Climate and management will interact to determine the forests of the future, and the scientific basis for adaptation to climate change in forests thus depends significantly on how forests will be affected.

Limited Transfer of Newly Acquired Movement Patterns across Walking and Running in Humans

PubMed Central

Ogawa, Tetsuya; Kawashima, Noritaka; Ogata, Toru; Nakazawa, Kimitaka

2012-01-01

The two major modes of locomotion in humans, walking and running, may be regarded as a function of different speed (walking as slower and running as faster). Recent results using motor learning tasks in humans, as well as more direct evidence from animal models, advocate for independence in the neural control mechanisms underlying different locomotion tasks. In the current study, we investigated the possible independence of the neural mechanisms underlying human walking and running. Subjects were tested on a split-belt treadmill and adapted to walking or running on an asymmetrically driven treadmill surface. Despite the acquisition of asymmetrical movement patterns in the respective modes, the emergence of asymmetrical movement patterns in the subsequent trials was evident only within the same modes (walking after learning to walk and running after learning to run) and only partial in the opposite modes (walking after learning to run and running after learning to walk) (thus transferred only limitedly across the modes). Further, the storage of the acquired movement pattern in each mode was maintained independently of the opposite mode. Combined, these results provide indirect evidence for independence in the neural control mechanisms underlying the two locomotive modes. PMID:23029490

Robust adaptive vibration control of a flexible structure.

PubMed

Khoshnood, A M; Moradi, H M

2014-07-01

Different types of L1 adaptive control systems show that using robust theories with adaptive control approaches has produced high performance controllers. In this study, a model reference adaptive control scheme considering robust theories is used to propose a practical control system for vibration suppression of a flexible launch vehicle (FLV). In this method, control input of the system is shaped from the dynamic model of the vehicle and components of the control input are adaptively constructed by estimating the undesirable vibration frequencies. Robust stability of the adaptive vibration control system is guaranteed by using the L1 small gain theorem. Simulation results of the robust adaptive vibration control strategy confirm that the effects of vibration on the vehicle performance considerably decrease without the loss of the phase margin of the system. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Optimal Control Modification for Robust Adaptation of Singularly Perturbed Systems with Slow Actuators

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.; Ishihara, Abraham; Stepanyan, Vahram; Boskovic, Jovan

2009-01-01

Recently a new optimal control modification has been introduced that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. This modification is based on an optimal control formulation to minimize the L2 norm of the tracking error. The optimal control modification adaptive law results in a stable adaptation in the presence of a large adaptive gain. This study examines the optimal control modification adaptive law in the context of a system with a time scale separation resulting from a fast plant with a slow actuator. A singular perturbation analysis is performed to derive a modification to the adaptive law by transforming the original system into a reduced-order system in slow time. The model matching conditions in the transformed time coordinate results in increase in the feedback gain and modification of the adaptive law.

Application of Bounded Linear Stability Analysis Method for Metrics-Driven Adaptive Control

NASA Technical Reports Server (NTRS)

Bakhtiari-Nejad, Maryam; Nguyen, Nhan T.; Krishnakumar, Kalmanje

2009-01-01

This paper presents the application of Bounded Linear Stability Analysis (BLSA) method for metrics-driven adaptive control. The bounded linear stability analysis method is used for analyzing stability of adaptive control models, without linearizing the adaptive laws. Metrics-driven adaptive control introduces a notion that adaptation should be driven by some stability metrics to achieve robustness. By the application of bounded linear stability analysis method the adaptive gain is adjusted during the adaptation in order to meet certain phase margin requirements. Analysis of metrics-driven adaptive control is evaluated for a second order system that represents a pitch attitude control of a generic transport aircraft. The analysis shows that the system with the metrics-conforming variable adaptive gain becomes more robust to unmodeled dynamics or time delay. The effect of analysis time-window for BLSA is also evaluated in order to meet the stability margin criteria.

Response to Thomas et al.: Biocontrol and indirect effects

Treesearch

Dean E. Pearson; Ragan M. Callaway

2004-01-01

In a recent TREE article [1], we identified three categories of unintended indirect effects that can arise from host-specific biological control agents: (i) ecological replacement; (ii) compensatory responses; and (iii) food-web interactions. Although our review focused on the biocontrol of plant pests, we suggested these concepts also apply to the biocontrol...

Bi-Objective Optimal Control Modification Adaptive Control for Systems with Input Uncertainty

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2012-01-01

This paper presents a new model-reference adaptive control method based on a bi-objective optimal control formulation for systems with input uncertainty. A parallel predictor model is constructed to relate the predictor error to the estimation error of the control effectiveness matrix. In this work, we develop an optimal control modification adaptive control approach that seeks to minimize a bi-objective linear quadratic cost function of both the tracking error norm and predictor error norm simultaneously. The resulting adaptive laws for the parametric uncertainty and control effectiveness uncertainty are dependent on both the tracking error and predictor error, while the adaptive laws for the feedback gain and command feedforward gain are only dependent on the tracking error. The optimal control modification term provides robustness to the adaptive laws naturally from the optimal control framework. Simulations demonstrate the effectiveness of the proposed adaptive control approach.

Adaptive neural network motion control for aircraft under uncertainty conditions

NASA Astrophysics Data System (ADS)

Efremov, A. V.; Tiaglik, M. S.; Tiumentsev, Yu V.

2018-02-01

We need to provide motion control of modern and advanced aircraft under diverse uncertainty conditions. This problem can be solved by using adaptive control laws. We carry out an analysis of the capabilities of these laws for such adaptive systems as MRAC (Model Reference Adaptive Control) and MPC (Model Predictive Control). In the case of a nonlinear control object, the most efficient solution to the adaptive control problem is the use of neural network technologies. These technologies are suitable for the development of both a control object model and a control law for the object. The approximate nature of the ANN model was taken into account by introducing additional compensating feedback into the control system. The capabilities of adaptive control laws under uncertainty in the source data are considered. We also conduct simulations to assess the contribution of adaptivity to the behavior of the system.

Identification of Indirect Effects in a Cognitive Patient Education (COPE) Intervention for Low Back Pain.

PubMed

Mansell, Gemma; Storheim, Kjersti; Løchting, Ida; Werner, Erik L; Grotle, Margreth

2017-12-01

Many interventions for the treatment of low back pain exist, but the mechanisms through which such treatments work are not always clear. This situation is especially true for biopsychosocial interventions that incorporate several different components and methods of delivery. The study objective was to examine the indirect effects of the Cognitive Patient Education (COPE) intervention via illness perceptions, back pain myths, and pain catastrophizing on disability outcome. This study was a secondary analysis of the COPE randomized controlled trial. Mediation analysis techniques were employed to examine the indirect effects of the COPE intervention via residualized change (baseline - posttreatment) in the 3 variables hypothesized to be targeted by the COPE intervention on posttreatment disability outcome. Pain intensity at baseline, pain duration, clinician type, and a treatment-mediator interaction term were controlled for in the analysis. Preliminary analyses confirmed that changes in pain catastrophizing and illness perceptions (not back pain myths) were related to both allocation to the intervention arm and posttreatment disability score. The treatment exerted statistically significant indirect effects via changes in illness perceptions and pain catastrophizing on posttreatment disability score (illness perceptions standardized indirect effect = 0.09 [95% CI = 0.03 to 0.16]; pain catastrophizing standardized indirect effect = 0.05 [95% CI = 0.01 to 0.12]). However, the inclusion of an interaction term led to the indirect effects being significantly reduced, with the effects no longer being statistically significant. This study presents a secondary analysis of variables not identified a priori as being potentially important treatment targets; other, unmeasured factors could also be important in explaining treatment effects. The finding that small indirect effects of the COPE intervention via changes in illness perceptions and pain catastrophizing on posttreatment disability could be estimated indicates that these variables may be viable treatment targets for biopsychosocial interventions; however, this finding must be viewed in light of the adjusted analyses, which showed that the indirect effects were significantly reduced through the inclusion of a treatment-mediator interaction term. © Crown copyright 2015

Adaptive powertrain control for plugin hybrid electric vehicles

DOEpatents

Kedar-Dongarkar, Gurunath; Weslati, Feisel

2013-10-15

A powertrain control system for a plugin hybrid electric vehicle. The system comprises an adaptive charge sustaining controller; at least one internal data source connected to the adaptive charge sustaining controller; and a memory connected to the adaptive charge sustaining controller for storing data generated by the at least one internal data source. The adaptive charge sustaining controller is operable to select an operating mode of the vehicle's powertrain along a given route based on programming generated from data stored in the memory associated with that route. Further described is a method of adaptively controlling operation of a plugin hybrid electric vehicle powertrain comprising identifying a route being traveled, activating stored adaptive charge sustaining mode programming for the identified route and controlling operation of the powertrain along the identified route by selecting from a plurality of operational modes based on the stored adaptive charge sustaining mode programming.

L(sub 1) Adaptive Flight Control System: Flight Evaluation and Technology Transition

NASA Technical Reports Server (NTRS)

Xargay, Enric; Hovakimyan, Naira; Dobrokhodov, Vladimir; Kaminer, Isaac; Gregory, Irene M.; Cao, Chengyu

2010-01-01

Certification of adaptive control technologies for both manned and unmanned aircraft represent a major challenge for current Verification and Validation techniques. A (missing) key step towards flight certification of adaptive flight control systems is the definition and development of analysis tools and methods to support Verification and Validation for nonlinear systems, similar to the procedures currently used for linear systems. In this paper, we describe and demonstrate the advantages of L(sub l) adaptive control architectures for closing some of the gaps in certification of adaptive flight control systems, which may facilitate the transition of adaptive control into military and commercial aerospace applications. As illustrative examples, we present the results of a piloted simulation evaluation on the NASA AirSTAR flight test vehicle, and results of an extensive flight test program conducted by the Naval Postgraduate School to demonstrate the advantages of L(sub l) adaptive control as a verifiable robust adaptive flight control system.

Parental perceptions of neighborhood processes, stress, personal control, and risk for physical child abuse and neglect.

PubMed

Guterman, Neil B; Lee, Shawna J; Taylor, Catherine A; Rathouz, Paul J

2009-12-01

This study set out to examine whether mothers' individual perceptions of their neighborhood social processes predict their risk for physical child abuse and neglect directly and/or indirectly via pathways involving parents' reported stress and sense of personal control in the parenting role. In-home and phone interview data were examined cross-sectionally from a national birth cohort sample of 3,356 mothers across 20 US cities when the index child was 3 years of age. Mothers' perceptions of neighborhood social processes, parenting stress, and personal control were examined as predictors, and three subscales of the Parent-To-Child Conflict Tactics Scale (CTS-PC) were employed as proxies of physical child abuse and neglect risk. Structural equation modeling (SEM) was employed to test direct and indirect pathways (via parenting stress and control) from perceived neighborhood processes to proxy measures of physical child abuse and neglect. Multiple group SEM was conducted to test for differences across major ethnic groups: African American, Hispanic, and White. Although perceived negative neighborhood processes had only a mild direct role in predicting risk for physical child abuse, and no direct role on child neglect, these perceptions had a discernable indirect role in predicting risk via parenting stress and personal control pathways. Parenting stress exerted the clearest direct role on both physical abuse and neglect risk. This predictor model did not significantly differ across ethnic groups. Although neighborhood conditions may not play a clear directly observable role on physical child abuse and neglect risk, the indirect role they play underscores the importance of parents' perceptions of their neighborhoods, and especially the role they play via parents' reported stress and personal control. Such findings suggest that targeting parents' sense of control and stress in relation to their immediate social environment holds particular potential to reduce physical child abuse and neglect risk. Addressing parents' perceptions of their neighborhood challenges may serve to reduce parenting risk via improving parents' felt control and stress.

Relevance of a neurophysiological marker of attention allocation for children's learning-related behaviors and academic performance.

PubMed

Willner, Cynthia J; Gatzke-Kopp, Lisa M; Bierman, Karen L; Greenberg, Mark T; Segalowitz, Sidney J

2015-08-01

Learning-related behaviors are important for school success. Socioeconomic disadvantage confers risk for less adaptive learning-related behaviors at school entry, yet substantial variability in school readiness exists within socioeconomically disadvantaged populations. Investigation of neurophysiological systems associated with learning-related behaviors in high-risk populations could illuminate resilience processes. This study examined the relevance of a neurophysiological measure of controlled attention allocation, amplitude of the P3b event-related potential, for learning-related behaviors and academic performance in a sample of socioeconomically disadvantaged kindergarteners. The sample consisted of 239 children from an urban, low-income community, approximately half of whom exhibited behavior problems at school entry (45% aggressive/oppositional; 64% male; 69% African American, 21% Hispanic). Results revealed that higher P3b amplitudes to target stimuli in a go/no-go task were associated with more adaptive learning-related behaviors in kindergarten. Furthermore, children's learning-related behaviors in kindergarten mediated a positive indirect effect of P3b amplitude on growth in academic performance from kindergarten to 1st grade. Given that P3b amplitude reflects attention allocation processes, these findings build on the scientific justification for interventions targeting young children's attention skills in order to promote effective learning-related behaviors and academic achievement within socioeconomically disadvantaged populations. (c) 2015 APA, all rights reserved).

The Csr system regulates genome-wide mRNA stability and transcription and thus gene expression in Escherichia coli.

PubMed

Esquerré, Thomas; Bouvier, Marie; Turlan, Catherine; Carpousis, Agamemnon J; Girbal, Laurence; Cocaign-Bousquet, Muriel

2016-04-26

Bacterial adaptation requires large-scale regulation of gene expression. We have performed a genome-wide analysis of the Csr system, which regulates many important cellular functions. The Csr system is involved in post-transcriptional regulation, but a role in transcriptional regulation has also been suggested. Two proteins, an RNA-binding protein CsrA and an atypical signaling protein CsrD, participate in the Csr system. Genome-wide transcript stabilities and levels were compared in wildtype E. coli (MG1655) and isogenic mutant strains deficient in CsrA or CsrD activity demonstrating for the first time that CsrA and CsrD are global negative and positive regulators of transcription, respectively. The role of CsrA in transcription regulation may be indirect due to the 4.6-fold increase in csrD mRNA concentration in the CsrA deficient strain. Transcriptional action of CsrA and CsrD on a few genes was validated by transcriptional fusions. In addition to an effect on transcription, CsrA stabilizes thousands of mRNAs. This is the first demonstration that CsrA is a global positive regulator of mRNA stability. For one hundred genes, we predict that direct control of mRNA stability by CsrA might contribute to metabolic adaptation by regulating expression of genes involved in carbon metabolism and transport independently of transcriptional regulation.

A Green's Function Approach to Simulate DNA Damage by the Indirect Effect

NASA Technical Reports Server (NTRS)

Plante, Ianik; Cicinotta, Francis A.

2013-01-01

The DNA damage is of fundamental importance in the understanding of the effects of ionizing radiation. DNA is damaged by the direct effect of radiation (e.g. direct ionization) and by indirect effect (e.g. damage by.OH radicals created by the radiolysis of water). Despite years of research, many questions on the DNA damage by ionizing radiation remains. In the recent years, the Green's functions of the diffusion equation (GFDE) have been used extensively in biochemistry [1], notably to simulate biochemical networks in time and space [2]. In our future work on DNA damage, we wish to use an approach based on the GFDE to refine existing models on the indirect effect of ionizing radiation on DNA. To do so, we will use the code RITRACKS [3] developed at the NASA Johnson Space Center to simulate the radiation track structure and calculate the position of radiolytic species after irradiation. We have also recently developed an efficient Monte-Carlo sampling algorithm for the GFDE of reversible reactions with an intermediate state [4], which can be modified and adapted to simulate DNA damage by free radicals. To do so, we will use the known reaction rate constants between radicals (OH, eaq, H,...) and the DNA bases, sugars and phosphates and use the sampling algorithms to simulate the diffusion of free radicals and chemical reactions with DNA. These techniques should help the understanding of the contribution of the indirect effect in the formation of DNA damage and double-strand breaks.

Mate-choice copying: A fitness-enhancing behavior that evolves by indirect selection.

PubMed

Santos, Mauro; Sapage, Manuel; Matos, Margarida; Varela, Susana A M

2017-06-01

A spatially explicit, individual-based simulation model is used to study the spread of an allele for mate-choice copying (MCC) through horizontal cultural transmission when female innate preferences do or do not coevolve with a male viability-increasing trait. Evolution of MCC is unlikely when innate female preferences coevolve with the trait, as copier females cannot express a higher preference than noncopier females for high-fitness males. However, if a genetic polymorphism for innate preference persists in the population, MCC can evolve by indirect selection through hitchhiking: the copying allele hitchhikes on the male trait. MCC can be an adaptive behavior-that is, a behavior that increases a population's average fitness relative to populations without MCC-even though the copying allele itself may be neutral or mildly deleterious. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Acculturation, Acculturative Stress, and Depressive Symptoms in International Migrants: A Study with Vietnamese Women in South Korea.

PubMed

Cho, Yong Ju; Jang, Yuri; Ko, Jung Eun; Lee, Sun Hae; Moon, Soo Kyung

2017-10-10

Globally, there have been increasing numbers of migrant women; these women are at an increased risk for depressive symptoms. The purpose of this study was to examine the associations among acculturation, acculturative stress and depressive symptoms in Vietnamese women who migrated to South Korea through marriages. We hypothesized that acculturative stress would serve as a mediator in the relationship between acculturation and depressive symptoms. Our findings from surveys with 217 Vietnamese immigrant women showed that the indirect effect of acculturation on depressive symptoms, mediated through acculturative stress [- .15 (.04)], was significant (bias corrected 95% confidence interval for the indirect effect = - .25, - .08). Low levels of acculturation increased acculturative stress, which in turn led to the elevated symptoms of depression. Our findings not only illuminate the adaptation processes of international, female migrants but also suggest avenues to protect and promote their mental well-being.

Longitudinal relations between parental media monitoring and adolescent aggression, prosocial behavior, and externalizing problems.

PubMed

Padilla-Walker, Laura M; Coyne, Sarah M; Collier, Kevin M

2016-01-01

The current study examined longitudinal relations between parental media monitoring and adolescent behavior, and explored indirect effects via sympathy and self-regulation. A sample of adolescents and their mothers from Northwestern and Mountain West cities in the USA participated in a study at three time points, approximately one year apart (N = 681; M age of child at Time 3 = 13.33, SD = 1.06; 51% female; 73% European American, 9% African American, 17% Multi-ethnic). Though findings varied by reporter, results suggested that restrictive and active media monitoring were indirectly associated with adolescents' prosocial behavior, aggression, and externalizing behavior, with restrictive monitoring being somewhat maladaptive and active monitoring adaptive. The discussion focuses on the need to examine multiple aspects of media monitoring, and highlights implications of findings for parents. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Indirect child mortality estimation technique to identify trends of under-five mortality in Ethiopia.

PubMed

Ayele, Dawit G; Zewotir, Temesgen; Mwambi, Henry

2016-03-01

In sub-Saharan African countries, the chance of a child dying before the age of five years is high. The problem is similar in Ethiopia, but it shows a decrease over years. The 2000; 2005 and 2011 Ethiopian Demographic and Health Survey results were used for this work. The purpose of the study is to detect the pattern of under-five child mortality overtime. Indirect child mortality estimation technique is adapted to examine the under-five child mortality trend in Ethiopia. From the result, it was possible to see the trend of under-five child mortality in Ethiopia. The under-five child mortality shows a decline in Ethiopia. From the study, it can be seen that there is a positive correlation between mother and child survival which is almost certain in any population. Therefore, this study shows the trend of under-five mortality in Ethiopia and decline over time.

The Psychological Effects of Climate Change on Children.

PubMed

Burke, Susie E L; Sanson, Ann V; Van Hoorn, Judith

2018-04-11

We review recent evidence on the psychological effects of climate change on children, covering both direct and indirect impacts, and discuss children's psychological adaptation to climate change. Both the direct and flow-on effects of climate change place children at risk of mental health consequences including PTSD, depression, anxiety, phobias, sleep disorders, attachment disorders, and substance abuse. These in turn can lead to problems with emotion regulation, cognition, learning, behavior, language development, and academic performance. Together, these create predispositions to adverse adult mental health outcomes. Children also exhibit high levels of concern over climate change. Meaning-focused coping promotes well-being and environmental engagement. Both direct and indirect climate change impacts affect children's psychological well-being. Children in the developing world will suffer the worst impacts. Mental health professionals have important roles in helping mitigate climate change, and researching and implementing approaches to helping children cope with its impacts.

Examining the psychology of working theory: Decent work among sexual minorities.

PubMed

Douglass, Richard P; Velez, Brandon L; Conlin, Sarah E; Duffy, Ryan D; England, Jessica W

2017-10-01

Research has found heterosexist discrimination negatively relates to vocational outcomes among lesbian, gay, and bisexual (LGB) people, but no known study has examined how heterosexist discrimination relates to the attainment of decent work. Building from the Psychology of Working Theory, which proposes that specific forms of marginalization coupled with economic constraints limit a person's ability to secure decent work, the present study examined theoretically hypothesized pathways to decent work among a sample of employed sexual minority adults. Heterosexist discrimination and social class were examined as direct predictors of decent work, and indirect links were examined via work volition and career adaptability. Among our sample of 218 sexual minority people, structural equation modeling results suggested heterosexist discrimination and social class directly-and indirectly through work volition-predicted decent work. Practical implications and directions for future research are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Biophysical regulation of stem cell differentiation.

PubMed

Govey, Peter M; Loiselle, Alayna E; Donahue, Henry J

2013-06-01

Bone adaptation to its mechanical environment, from embryonic through adult life, is thought to be the product of increased osteoblastic differentiation from mesenchymal stem cells. In parallel with tissue-scale loading, these heterogeneous populations of multipotent stem cells are subject to a variety of biophysical cues within their native microenvironments. Bone marrow-derived mesenchymal stem cells-the most broadly studied source of osteoblastic progenitors-undergo osteoblastic differentiation in vitro in response to biophysical signals, including hydrostatic pressure, fluid flow and accompanying shear stress, substrate strain and stiffness, substrate topography, and electromagnetic fields. Furthermore, stem cells may be subject to indirect regulation by mechano-sensing osteocytes positioned to more readily detect these same loading-induced signals within the bone matrix. Such paracrine and juxtacrine regulation of differentiation by osteocytes occurs in vitro. Further studies are needed to confirm both direct and indirect mechanisms of biophysical regulation within the in vivo stem cell niche.

A novel composite adaptive flap controller design by a high-efficient modified differential evolution identification approach.

PubMed

Li, Nailu; Mu, Anle; Yang, Xiyun; Magar, Kaman T; Liu, Chao

2018-05-01

The optimal tuning of adaptive flap controller can improve adaptive flap control performance on uncertain operating environments, but the optimization process is usually time-consuming and it is difficult to design proper optimal tuning strategy for the flap control system (FCS). To solve this problem, a novel adaptive flap controller is designed based on a high-efficient differential evolution (DE) identification technique and composite adaptive internal model control (CAIMC) strategy. The optimal tuning can be easily obtained by DE identified inverse of the FCS via CAIMC structure. To achieve fast tuning, a high-efficient modified adaptive DE algorithm is proposed with new mutant operator and varying range adaptive mechanism for the FCS identification. A tradeoff between optimized adaptive flap control and low computation cost is successfully achieved by proposed controller. Simulation results show the robustness of proposed method and its superiority to conventional adaptive IMC (AIMC) flap controller and the CAIMC flap controllers using other DE algorithms on various uncertain operating conditions. The high computation efficiency of proposed controller is also verified based on the computation time on those operating cases. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Indirect synchronization control in a starlike network of phase oscillators

NASA Astrophysics Data System (ADS)

Kuptsov, Pavel V.; Kuptsova, Anna V.

2018-04-01

A starlike network of non-identical phase oscillators is considered that contains the hub and tree rays each having a single node. In such network effect of indirect synchronization control is reported: changing the natural frequency and the coupling strength of one of the peripheral oscillators one can switch on an off the synchronization of the others. The controlling oscillator at that is not synchronized with them and has a frequency that is approximately four time higher then the frequency of the synchronization. The parameter planes showing a corresponding synchronization tongue are represented and time dependencies of phase differences are plotted for points within and outside of the tongue.

Representing and Learning Complex Object Interactions

PubMed Central

Zhou, Yilun; Konidaris, George

2017-01-01

We present a framework for representing scenarios with complex object interactions, in which a robot cannot directly interact with the object it wishes to control, but must instead do so via intermediate objects. For example, a robot learning to drive a car can only indirectly change its pose, by rotating the steering wheel. We formalize such complex interactions as chains of Markov decision processes and show how they can be learned and used for control. We describe two systems in which a robot uses learning from demonstration to achieve indirect control: playing a computer game, and using a hot water dispenser to heat a cup of water. PMID:28593181

Flight Validation of a Metrics Driven L(sub 1) Adaptive Control

NASA Technical Reports Server (NTRS)

Dobrokhodov, Vladimir; Kitsios, Ioannis; Kaminer, Isaac; Jones, Kevin D.; Xargay, Enric; Hovakimyan, Naira; Cao, Chengyu; Lizarraga, Mariano I.; Gregory, Irene M.

2008-01-01

The paper addresses initial steps involved in the development and flight implementation of new metrics driven L1 adaptive flight control system. The work concentrates on (i) definition of appropriate control driven metrics that account for the control surface failures; (ii) tailoring recently developed L1 adaptive controller to the design of adaptive flight control systems that explicitly address these metrics in the presence of control surface failures and dynamic changes under adverse flight conditions; (iii) development of a flight control system for implementation of the resulting algorithms onboard of small UAV; and (iv) conducting a comprehensive flight test program that demonstrates performance of the developed adaptive control algorithms in the presence of failures. As the initial milestone the paper concentrates on the adaptive flight system setup and initial efforts addressing the ability of a commercial off-the-shelf AP with and without adaptive augmentation to recover from control surface failures.

Direct adaptive control of manipulators in Cartesian space

NASA Technical Reports Server (NTRS)

Seraji, H.

1987-01-01

A new adaptive-control scheme for direct control of manipulator end effector to achieve trajectory tracking in Cartesian space is developed in this article. The control structure is obtained from linear multivariable theory and is composed of simple feedforward and feedback controllers and an auxiliary input. The direct adaptation laws are derived from model reference adaptive control theory and are not based on parameter estimation of the robot model. The utilization of adaptive feedforward control and the inclusion of auxiliary input are novel features of the present scheme and result in improved dynamic performance over existing adaptive control schemes. The adaptive controller does not require the complex mathematical model of the robot dynamics or any knowledge of the robot parameters or the payload, and is computationally fast for on-line implementation with high sampling rates. The control scheme is applied to a two-link manipulator for illustration.

Not just sticks and stones: Indirect ethnic discrimination leads to greater physiological reactivity.

PubMed

Huynh, Virginia W; Huynh, Que-Lam; Stein, Mary-Patricia

2017-07-01

We examined the effect of indirect ethnic discrimination on physiological reactivity (i.e., cortisol, blood pressure, heart rate) in Latino emerging adults. Participants (N = 32) were randomly assigned to be exposed to indirect ethnic discrimination (experimental condition) or not (control condition) while undergoing a cognitive stress task. Greater total cortisol output was observed in participants in the experimental condition, relative to those in the control condition. No significant differences in heart rate or blood pressure were noted. Results suggest that witnessing ethnic discrimination affects cortisol recovery responses, but not cardiovascular reactivity. Words that are not intentionally hurtful or directed at a specific person may still "hurt"-affecting biological processes associated with hypothalamic-pituitary-adrenocortical (HPA) axis and potentially leading to long-term health consequences. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Adaptive control of dual-arm robots

NASA Technical Reports Server (NTRS)

Seraji, H.

1987-01-01

Three strategies for adaptive control of cooperative dual-arm robots are described. In the position-position control strategy, the adaptive controllers ensure that the end-effector positions of both arms track desired trajectories in Cartesian space despite unknown time-varying interaction forces exerted through the load. In the position-hybrid control strategy, the adaptive controller of one arm controls end-effector motions in the free directions and applied forces in the constraint directions, while the adaptive controller of the other arm ensures that the end-effector tracks desired position trajectories. In the hybrid-hybrid control strategy, the adaptive controllers ensure that both end-effectors track reference position trajectories while simultaneously applying desired forces on the load. In all three control strategies, the cross-coupling effects between the arms are treated as disturbances which are rejected by the adaptive controllers while following desired commands in a common frame of reference. The adaptive controllers do not require the complex mathematical model of the arm dynamics or any knowledge of the arm dynamic parameters or the load parameters such as mass and stiffness. The controllers have simple structures and are computationally fast for on-line implementation with high sampling rates.

Speed Sensorless Induction Motor Drives for Electrical Actuators: Schemes, Trends and Tradeoffs

NASA Technical Reports Server (NTRS)

Elbuluk, Malik E.; Kankam, M. David

1997-01-01

For a decade, induction motor drive-based electrical actuators have been under investigation as potential replacement for the conventional hydraulic and pneumatic actuators in aircraft. Advantages of electric actuator include lower weight and size, reduced maintenance and operating costs, improved safety due to the elimination of hazardous fluids and high pressure hydraulic and pneumatic actuators, and increased efficiency. Recently, the emphasis of research on induction motor drives has been on sensorless vector control which eliminates flux and speed sensors mounted on the motor. Also, the development of effective speed and flux estimators has allowed good rotor flux-oriented (RFO) performance at all speeds except those close to zero. Sensorless control has improved the motor performance, compared to the Volts/Hertz (or constant flux) controls. This report evaluates documented schemes for speed sensorless drives, and discusses the trends and tradeoffs involved in selecting a particular scheme. These schemes combine the attributes of the direct and indirect field-oriented control (FOC) or use model adaptive reference systems (MRAS) with a speed-dependent current model for flux estimation which tracks the voltage model-based flux estimator. Many factors are important in comparing the effectiveness of a speed sensorless scheme. Among them are the wide speed range capability, motor parameter insensitivity and noise reduction. Although a number of schemes have been proposed for solving the speed estimation, zero-speed FOC with robustness against parameter variations still remains an area of research for speed sensorless control.

To Do or Not to Do: Dopamine, Affordability and the Economics of Opportunity.

PubMed

Beeler, Jeff A; Mourra, Devry

2018-01-01

Five years ago, we introduced the thrift hypothesis of dopamine (DA), suggesting that the primary role of DA in adaptive behavior is regulating behavioral energy expenditure to match the prevailing economic conditions of the environment. Here we elaborate that hypothesis with several new ideas. First, we introduce the concept of affordability, suggesting that costs must necessarily be evaluated with respect to the availability of resources to the organism, which computes a value not only for the potential reward opportunity, but also the value of resources expended. Placing both costs and benefits within the context of the larger economy in which the animal is functioning requires consideration of the different timescales against which to compute resource availability, or average reward rate. Appropriate windows of computation for tracking resources requires corresponding neural substrates that operate on these different timescales. In discussing temporal patterns of DA signaling, we focus on a neglected form of DA plasticity and adaptation, changes in the physical substrate of the DA system itself, such as up- and down-regulation of receptors or release probability. We argue that changes in the DA substrate itself fundamentally alter its computational function, which we propose mediates adaptations to longer temporal horizons and economic conditions. In developing our hypothesis, we focus on DA D2 receptors (D2R), arguing that D2R implements a form of "cost control" in response to the environmental economy, serving as the "brain's comptroller". We propose that the balance between the direct and indirect pathway, regulated by relative expression of D1 and D2 DA receptors, implements affordability. Finally, as we review data, we discuss limitations in current approaches that impede fully investigating the proposed hypothesis and highlight alternative, more semi-naturalistic strategies more conducive to neuroeconomic investigations on the role of DA in adaptive behavior.

The Temperature Dependence of Phytoplankton Stoichiometry: Investigating the Roles of Species Sorting and Local Adaptation

PubMed Central

Yvon-Durocher, Gabriel; Schaum, Charlotte-Elisa; Trimmer, Mark

2017-01-01

The elemental composition of phytoplankton (C:N:P stoichiometry) is a critical factor regulating nutrient cycling, primary production and energy transfer through planktonic food webs. Our understanding of the multiple direct and indirect mechanisms through which temperature controls phytoplankton stoichiometry is however incomplete, increasing uncertainty in the impacts of global warming on the biogeochemical functioning of aquatic ecosystems. Here, we use a decade-long warming experiment in outdoor freshwater ponds to investigate how temperature-driven turnover in species composition and shifts in stoichiometric traits within species through local thermal adaptation contribute to the effects of warming on seston stoichiometry. We found that experimental warming increased seston C:P and N:P ratios, while the C:N ratio was unaffected by warming. Temperature was also the dominant driver of seasonal variation in seston stoichiometry, correlating positively with both C:P and N:P ratios. The taxonomic composition of the phytoplankton community differed substantially between the warmed and ambient treatments indicating that warming resulted in differential sorting of species from the regional pool. Furthermore, taxonomic composition also changed markedly over the year within each of the warmed and ambient treatments, highlighting substantial temporal turnover in species. To investigate whether local adaptation also played an important role in shaping the effects of warming on seston stoichiometry, we isolated multiple strains of the cosmopolitan alga, Chlamydomonas reinhardtii from across the warmed and ambient mesocosms. We found that warmed isolates had higher C:P and N:P ratios, shifts that were comparable in direction and magnitude to the effects of warming on seston stoichiometry. Our results suggest that both species sorting and local adaptation are likely to play important roles in shaping the effects of warming on bulk phytoplankton stoichiometry and indicate that major shifts in aquatic biogeochemistry should be expected in a warmer world. PMID:29109703

Transcriptome signatures of class I and III stress response deregulation in Lactobacillus plantarum reveal pleiotropic adaptation

PubMed Central

2013-01-01

Background To cope with environmental challenges bacteria possess sophisticated defense mechanisms that involve stress-induced adaptive responses. The canonical stress regulators CtsR and HrcA play a central role in the adaptations to a plethora of stresses in a variety of organisms. Here, we determined the CtsR and HrcA regulons of the lactic acid bacterium Lactobacillus plantarum WCFS1 grown under reference (28°C) and elevated (40°C) temperatures, using ctsR, hrcA, and ctsR-hrcA deletion mutants. Results While the maximum specific growth rates of the mutants and the parental strain were similar at both temperatures (0.33 ± 0.02 h-1 and 0.34 ± 0.03 h-1, respectively), DNA microarray analyses revealed that the CtsR or HrcA deficient strains displayed altered transcription patterns of genes encoding functions involved in transport and binding of sugars and other compounds, primary metabolism, transcription regulation, capsular polysaccharide biosynthesis, as well as fatty acid metabolism. These transcriptional signatures enabled the refinement of the gene repertoire that is directly or indirectly controlled by CtsR and HrcA of L. plantarum. Deletion of both regulators, elicited transcriptional changes of a large variety of additional genes in a temperature-dependent manner, including genes encoding functions involved in cell-envelope remodeling. Moreover, phenotypic assays revealed that both transcription regulators contribute to regulation of resistance to hydrogen peroxide stress. The integration of these results allowed the reconstruction of CtsR and HrcA regulatory networks in L. plantarum, highlighting the significant intertwinement of class I and III stress regulons. Conclusions Taken together, our results enabled the refinement of the CtsR and HrcA regulatory networks in L. plantarum, illustrating the complex nature of adaptive stress responses in this bacterium. PMID:24238744

Altered vestibular function in fetal and newborn rats gestated in space

NASA Technical Reports Server (NTRS)

Ronca, A. E.; Alberts, J. R.

1997-01-01

Researchers evaluated vestibular development and function in rat pups flown during gestation on the NASA-NIH R1 and R2 missions. Fetal and postnatal vestibular function were examined. Altered vestibular-mediated responses in the experimental fetal pups are attributed to either direct effect of gravity on the vestibular system or indirect effects of microgravity transduced through the mother. The postnatal tests confirmed the hypothesis that the vestibular system continually adapts and responds to tonic stimulation.

Programs Addressing Psychological Health and Traumatic Brain Injury Among U.S. Military Servicemembers and Their Families

DTIC Science & Technology

2011-01-01

deficit hyperactivity disorder AFB Air Force Base AFI Air Force Instruction AFPD Air Force Policy Directive AFSOC Air Force Special Operations Command...Acknowledge, Care, and Tell ADAMS Alcohol and Drug Abuse Managers/Supervisors ADAPT Alcohol and Drug Abuse Prevention and Treatment ADHD attention ...stress disorder (PTSD, an anxiety disorder that can develop after direct or indirect exposure to an event or ordeal in which grave physical harm occurred

Linking amphibian call structure to the environment: the interplay between phenotypic flexibility and individual attributes.

PubMed

Ziegler, Lucía; Arim, Matías; Narins, Peter M

2011-05-01

The structure of the environment surrounding signal emission produces different patterns of degradation and attenuation. The expected adjustment of calls to ensure signal transmission in an environment was formalized in the acoustic adaptation hypothesis. Within this framework, most studies considered anuran calls as fixed attributes determined by local adaptations. However, variability in vocalizations as a product of phenotypic expression has also been reported. Empirical evidence supporting the association between environment and call structure has been inconsistent, particularly in anurans. Here, we identify a plausible causal structure connecting environment, individual attributes, and temporal and spectral adjustments as direct or indirect determinants of the observed variation in call attributes of the frog Hypsiboas pulchellus. For that purpose, we recorded the calls of 40 males in the field, together with vegetation density and other environmental descriptors of the calling site. Path analysis revealed a strong effect of habitat structure on the temporal parameters of the call, and an effect of site temperature conditioning the size of organisms calling at each site and thus indirectly affecting the dominant frequency of the call. Experimental habitat modification with a styrofoam enclosure yielded results consistent with field observations, highlighting the potential role of call flexibility on detected call patterns. Both, experimental and correlative results indicate the need to incorporate the so far poorly considered role of phenotypic plasticity in the complex connection between environmental structure and individual call attributes.

A Secure Base from which to Cooperate: Security, Child and Parent Willing Stance, and Adaptive and Maladaptive Outcomes in two Longitudinal Studies.

PubMed

Goffin, Kathryn C; Boldt, Lea J; Kochanska, Grazyna

2017-10-17

Early secure attachment plays a key role in socialization by inaugurating a long-term mutual positive, collaborative interpersonal orientation within the parent-child dyad. We report findings from Family Study (community mothers, fathers, and children, from age 2 to 12, N = 102, 51 girls) and Play Study (exclusively low-income mothers and children, from age 3.5 to 7, N = 186, 90 girls). We examined links among observed secure attachment at toddler age, child and parent receptive, willing stance to each other, observed in parent-child contexts at early school age, and developmental outcomes. The developmental outcomes included parent-rated child antisocial behavior problems and observed positive mutuality with regard to conflict issues at age 12 in Family Study, and mother-rated child antisocial behavior problems and observed child regard for rules and moral self at age 7 in Play Study. In mother-child relationships, the child's willing stance mediated indirect effects of child security on positive mutuality in Family Study and on all outcomes in Play Study. In father-child relationships, both the child's and the parent's willing stance mediated indirect effects of child security on both outcomes. Early security initiates an adaptive developmental cascade by enlisting the child and the parent as active, willingly receptive and cooperative agents in the socialization process. Implications for children's parenting interventions are noted.

Future goal setting, task motivation and learning of minority and non-minority students in Dutch schools.

PubMed

Andriessen, Iris; Phalet, Karen; Lens, Willy

2006-12-01

Cross-cultural research on minority school achievement yields mixed findings on the motivational impact of future goal setting for students from disadvantaged minority groups. Relevant and recent motivational research, integrating Future Time Perspective Theory with Self-Determination Theory, has not yet been validated among minority students. To replicate across cultures the known motivational benefits of perceived instrumentality and internal regulation by distant future goals; to clarify when and how the future motivates minority students' educational performance. Participants in this study were 279 minority students (100 of Turkish and 179 of Moroccan origin) and 229 native Dutch students in Dutch secondary schools. Participants rated the importance of future goals, their perceptions of instrumentality, their task motivation and learning strategies. Dependent measures and their functional relations with future goal setting were simultaneously validated across minority and non-minority students, using structural equation modelling in multiple groups. As expected, Positive Perceived Instrumentality for the future increases task motivation and (indirectly) adaptive learning of both minority and non-minority students. But especially internally regulating future goals are strongly related to more task motivation and indirectly to more adaptive learning strategies. Our findings throw new light on the role of future goal setting in minority school careers: distant future goals enhance minority and non-minority students' motivation and learning, if students perceive positive instrumentality and if their schoolwork is internally regulated by future goals.

Optimal Control Modification Adaptive Law for Time-Scale Separated Systems

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2010-01-01

Recently a new optimal control modification has been introduced that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. This modification is based on an optimal control formulation to minimize the L2 norm of the tracking error. The optimal control modification adaptive law results in a stable adaptation in the presence of a large adaptive gain. This study examines the optimal control modification adaptive law in the context of a system with a time scale separation resulting from a fast plant with a slow actuator. A singular perturbation analysis is performed to derive a modification to the adaptive law by transforming the original system into a reduced-order system in slow time. A model matching conditions in the transformed time coordinate results in an increase in the actuator command that effectively compensate for the slow actuator dynamics. Simulations demonstrate effectiveness of the method.

A direct CO2 control system for ocean acidification experiments: testing effects on the coralline red algae Phymatolithon lusitanicum.

PubMed

Sordo, Laura; Santos, Rui; Reis, Joao; Shulika, Alona; Silva, Joao

2016-01-01

Most ocean acidification (OA) experimental systems rely on pH as an indirect way to control CO 2 . However, accurate pH measurements are difficult to obtain and shifts in temperature and/or salinity alter the relationship between pH and p CO 2 . Here we describe a system in which the target p CO 2 is controlled via direct analysis of p CO 2 in seawater. This direct type of control accommodates potential temperature and salinity shifts, as the target variable is directly measured instead of being estimated. Water in a header tank is permanently re-circulated through an air-water equilibrator. The equilibrated air is then routed to an infrared gas analyzer (IRGA) that measures p CO 2 and conveys this value to a Proportional-Integral-Derivative (PID) controller. The controller commands a solenoid valve that opens and closes the CO 2 flush that is bubbled into the header tank. This low-cost control system allows the maintenance of stabilized levels of p CO 2 for extended periods of time ensuring accurate experimental conditions. This system was used to study the long term effect of OA on the coralline red algae Phymatolithon lusitanicum . We found that after 11 months of high CO 2 exposure, photosynthesis increased with CO 2 as opposed to respiration, which was positively affected by temperature. Results showed that this system is adequate to run long-term OA experiments and can be easily adapted to test other relevant variables simultaneously with CO 2 , such as temperature, irradiance and nutrients.

A direct CO2 control system for ocean acidification experiments: testing effects on the coralline red algae Phymatolithon lusitanicum

PubMed Central

Santos, Rui; Reis, Joao; Shulika, Alona

2016-01-01

Most ocean acidification (OA) experimental systems rely on pH as an indirect way to control CO2. However, accurate pH measurements are difficult to obtain and shifts in temperature and/or salinity alter the relationship between pH and pCO2. Here we describe a system in which the target pCO2 is controlled via direct analysis of pCO2 in seawater. This direct type of control accommodates potential temperature and salinity shifts, as the target variable is directly measured instead of being estimated. Water in a header tank is permanently re-circulated through an air-water equilibrator. The equilibrated air is then routed to an infrared gas analyzer (IRGA) that measures pCO2 and conveys this value to a Proportional-Integral-Derivative (PID) controller. The controller commands a solenoid valve that opens and closes the CO2 flush that is bubbled into the header tank. This low-cost control system allows the maintenance of stabilized levels of pCO2 for extended periods of time ensuring accurate experimental conditions. This system was used to study the long term effect of OA on the coralline red algae Phymatolithon lusitanicum. We found that after 11 months of high CO2 exposure, photosynthesis increased with CO2 as opposed to respiration, which was positively affected by temperature. Results showed that this system is adequate to run long-term OA experiments and can be easily adapted to test other relevant variables simultaneously with CO2, such as temperature, irradiance and nutrients. PMID:27703853

Vibration control of a ship engine system using high-load magnetorheological mounts associated with a new indirect fuzzy sliding mode controller

NASA Astrophysics Data System (ADS)

Phu, Do Xuan; Choi, Seung-Bok

2015-02-01

In this work, a new high-load magnetorheological (MR) fluid mount system is devised and applied to control vibration in a ship engine. In the investigation of vibration-control performance, a new modified indirect fuzzy sliding mode controller is formulated and realized. The design of the proposed MR mount is based on the flow mode of MR fluid, and it includes two separated coils for generating a magnetic field. An optimization process is carried out to achieve maximal damping force under certain design constraints, such as the allowable height of the mount. As an actuating smart fluid, a new plate-like iron-particle-based MR fluid is used, instead of the conventional spherical iron-particle-based MR fluid. After evaluating the field-dependent yield stress of the MR fluid, the field-dependent damping force required to control unwanted vibration in the ship engine is determined. Subsequently, an appropriate-sized MR mount is manufactured and its damping characteristics are evaluated. After confirming the sufficient damping force level of the manufactured MR mount, a medium-sized ship engine mount system consisting of eight MR mounts is established, and its dynamic governing equations are derived. A new modified indirect fuzzy sliding mode controller is then formulated and applied to the engine mount system. The displacement and velocity responses show that the unwanted vibrations of the ship engine system can be effectively controlled in both the axial and radial directions by applying the proposed control methodology.

Indirect Comparisons: A Review of Reporting and Methodological Quality

PubMed Central

Donegan, Sarah; Williamson, Paula; Gamble, Carrol; Tudur-Smith, Catrin

2010-01-01

Background The indirect comparison of two interventions can be valuable in many situations. However, the quality of an indirect comparison will depend on several factors including the chosen methodology and validity of underlying assumptions. Published indirect comparisons are increasingly more common in the medical literature, but as yet, there are no published recommendations of how they should be reported. Our aim is to systematically review the quality of published indirect comparisons to add to existing empirical data suggesting that improvements can be made when reporting and applying indirect comparisons. Methodology/Findings Reviews applying statistical methods to indirectly compare the clinical effectiveness of two interventions using randomised controlled trials were eligible. We searched (1966–2008) Database of Abstracts and Reviews of Effects, The Cochrane library, and Medline. Full review publications were assessed for eligibility. Specific criteria to assess quality were developed and applied. Forty-three reviews were included. Adequate methodology was used to calculate the indirect comparison in 41 reviews. Nineteen reviews assessed the similarity assumption using sensitivity analysis, subgroup analysis, or meta-regression. Eleven reviews compared trial-level characteristics. Twenty-four reviews assessed statistical homogeneity. Twelve reviews investigated causes of heterogeneity. Seventeen reviews included direct and indirect evidence for the same comparison; six reviews assessed consistency. One review combined both evidence types. Twenty-five reviews urged caution in interpretation of results, and 24 reviews indicated when results were from indirect evidence by stating this term with the result. Conclusions This review shows that the underlying assumptions are not routinely explored or reported when undertaking indirect comparisons. We recommend, therefore, that the quality of indirect comparisons should be improved, in particular, by assessing assumptions and reporting the assessment methods applied. We propose that the quality criteria applied in this article may provide a basis to help review authors carry out indirect comparisons and to aid appropriate interpretation. PMID:21085712

Fast spacecraft adaptive attitude tracking control through immersion and invariance design

NASA Astrophysics Data System (ADS)

Wen, Haowei; Yue, Xiaokui; Li, Peng; Yuan, Jianping

2017-10-01

This paper presents a novel non-certainty-equivalence adaptive control method for the attitude tracking control problem of spacecraft with inertia uncertainties. The proposed immersion and invariance (I&I) based adaptation law provides a more direct and flexible approach to circumvent the limitations of the basic I&I method without employing any filter signal. By virtue of the adaptation high-gain equivalence property derived from the proposed adaptive method, the closed-loop adaptive system with a low adaptation gain could recover the high adaptation gain performance of the filter-based I&I method, and the resulting control torque demands during the initial transient has been significantly reduced. A special feature of this method is that the convergence of the parameter estimation error has been observably improved by utilizing an adaptation gain matrix instead of a single adaptation gain value. Numerical simulations are presented to highlight the various benefits of the proposed method compared with the certainty-equivalence-based control method and filter-based I&I control schemes.

Decentralized adaptive control

NASA Technical Reports Server (NTRS)

Oh, B. J.; Jamshidi, M.; Seraji, H.

1988-01-01

A decentralized adaptive control is proposed to stabilize and track the nonlinear, interconnected subsystems with unknown parameters. The adaptation of the controller gain is derived by using model reference adaptive control theory based on Lyapunov's direct method. The adaptive gains consist of sigma, proportional, and integral combination of the measured and reference values of the corresponding subsystem. The proposed control is applied to the joint control of a two-link robot manipulator, and the performance in computer simulation corresponds with what is expected in theoretical development.

Mathematical model of an indirect action fuel flow controller for aircraft jet engines

NASA Astrophysics Data System (ADS)

Tudosie, Alexandru-Nicolae

2017-06-01

The paper deals with a fuel mass flow rate controller with indirect action for aircraft jet engines. The author has identified fuel controller's main parts and its operation mode, then, based on these observations, one has determined motion equations of each main part, which have built system's non-linear mathematical model. In order to realize a better study this model was linearised (using the finite differences method) and then adimensionalized. Based on this new form of the mathematical model, after applying Laplace transformation, the embedded system (controller+engine) was described by the block diagram with transfer functions. Some Simulink-Matlab simulations were performed, concerning system's time behavior for step input, which lead to some useful conclusions and extension possibilities.

Glyphosate toxicity and the effects of long-term vegetation control on soil microbial communities

Treesearch

Matt D. Busse; Alice W. Ratcliff; Carol J. Stestak; Robert F. Powers

2001-01-01

We assessed the direct and indirect effect of the herbicide glyphosate on soil microbial communities from soil bioassays at glyphosate concentrations up to 100-fold greater than expected following a single field application. Indirect effects on microbial biomass, respiration, and metabolic diversity (Biolog and catabolic response profile) were compared seasonally after...

76 FR 65288 - Self-Regulatory Organizations; New York Stock Exchange, LLC; Notice of Filing of Proposed Rule...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-20

... voting limitations would apply only for so long as NYSE Group directly or indirectly controls any... Germany (``Deutsche B[ouml]rse''). NYSE Euronext owns 100% of the equity interest of NYSE Group, Inc., a Delaware corporation (``NYSE Group''), which in turn directly or indirectly owns (1) 100% of the equity...

76 FR 65272 - Self-Regulatory Organizations; NYSE Amex LLC; Notice of Filing of Proposed Rule Change Relating...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-20

... voting limitations would apply only for so long as NYSE Group directly or indirectly controls any... Republic of Germany (``Deutsche B[ouml]rse''). NYSE Euronext owns 100% of the equity interest of NYSE Group, Inc., a Delaware corporation (``NYSE Group''), which in turn directly or indirectly owns (1) 100% of...

Birth weight predicted baseline muscular efficiency, but not response of energy expenditure to calorie restriction: An empirical test of the predictive adaptive response hypothesis.

PubMed

Workman, Megan; Baker, Jack; Lancaster, Jane B; Mermier, Christine; Alcock, Joe

2016-07-01

Aiming to test the evolutionary significance of relationships linking prenatal growth conditions to adult phenotypes, this study examined whether birth size predicts energetic savings during fasting. We specifically tested a Predictive Adaptive Response (PAR) model that predicts greater energetic saving among adults who were born small. Data were collected from a convenience sample of young adults living in Albuquerque, NM (n = 34). Indirect calorimetry quantified changes in resting energy expenditure (REE) and active muscular efficiency that occurred in response to a 29-h fast. Multiple regression analyses linked birth weight to baseline and postfast metabolic values while controlling for appropriate confounders (e.g., sex, body mass). Birth weight did not moderate the relationship between body size and energy expenditure, nor did it predict the magnitude change in REE or muscular efficiency observed from baseline to after fasting. Alternative indicators of birth size were also examined (e.g., low v. normal birth weight, comparison of tertiles), with no effects found. However, baseline muscular efficiency improved by 1.1% per 725 g (S.D.) increase in birth weight (P = 0.037). Birth size did not influence the sensitivity of metabolic demands to fasting-neither at rest nor during activity. Moreover, small birth size predicted a reduction in the efficiency with which muscles convert energy expended into work accomplished. These results do not support the ascription of adaptive function to phenotypes associated with small birth size. © 2015 Wiley Periodicals, Inc. Am. J. Hum. Biol. 28:484-492, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Engine cylinder pressure reconstruction using crank kinematics and recurrently-trained neural networks

NASA Astrophysics Data System (ADS)

Bennett, C.; Dunne, J. F.; Trimby, S.; Richardson, D.

2017-02-01

A recurrent non-linear autoregressive with exogenous input (NARX) neural network is proposed, and a suitable fully-recurrent training methodology is adapted and tuned, for reconstructing cylinder pressure in multi-cylinder IC engines using measured crank kinematics. This type of indirect sensing is important for cost effective closed-loop combustion control and for On-Board Diagnostics. The challenge addressed is to accurately predict cylinder pressure traces within the cycle under generalisation conditions: i.e. using data not previously seen by the network during training. This involves direct construction and calibration of a suitable inverse crank dynamic model, which owing to singular behaviour at top-dead-centre (TDC), has proved difficult via physical model construction, calibration, and inversion. The NARX architecture is specialised and adapted to cylinder pressure reconstruction, using a fully-recurrent training methodology which is needed because the alternatives are too slow and unreliable for practical network training on production engines. The fully-recurrent Robust Adaptive Gradient Descent (RAGD) algorithm, is tuned initially using synthesised crank kinematics, and then tested on real engine data to assess the reconstruction capability. Real data is obtained from a 1.125 l, 3-cylinder, in-line, direct injection spark ignition (DISI) engine involving synchronised measurements of crank kinematics and cylinder pressure across a range of steady-state speed and load conditions. The paper shows that a RAGD-trained NARX network using both crank velocity and crank acceleration as input information, provides fast and robust training. By using the optimum epoch identified during RAGD training, acceptably accurate cylinder pressures, and especially accurate location-of-peak-pressure, can be reconstructed robustly under generalisation conditions, making it the most practical NARX configuration and recurrent training methodology for use on production engines.

Enhanced in planta Fitness through Adaptive Mutations in EfpR, a Dual Regulator of Virulence and Metabolic Functions in the Plant Pathogen Ralstonia solanacearum.

PubMed

Perrier, Anthony; Peyraud, Rémi; Rengel, David; Barlet, Xavier; Lucasson, Emmanuel; Gouzy, Jérôme; Peeters, Nemo; Genin, Stéphane; Guidot, Alice

2016-12-01

Experimental evolution of the plant pathogen Ralstonia solanacearum, where bacteria were maintained on plant lineages for more than 300 generations, revealed that several independent single mutations in the efpR gene from populations propagated on beans were associated with fitness gain on bean. In the present work, novel allelic efpR variants were isolated from populations propagated on other plant species, thus suggesting that mutations in efpR were not solely associated to a fitness gain on bean, but also on additional hosts. A transcriptomic profiling and phenotypic characterization of the efpR deleted mutant showed that EfpR acts as a global catabolic repressor, directly or indirectly down-regulating the expression of multiple metabolic pathways. EfpR also controls virulence traits such as exopolysaccharide production, swimming and twitching motilities and deletion of efpR leads to reduced virulence on tomato plants after soil drenching inoculation. We studied the impact of the single mutations that occurred in efpR during experimental evolution and found that these allelic mutants displayed phenotypic characteristics similar to the deletion mutant, although not behaving as complete loss-of-function mutants. These adaptive mutations therefore strongly affected the function of efpR, leading to an expanded metabolic versatility that should benefit to the evolved clones. Altogether, these results indicated that EfpR is a novel central player of the R. solanacearum virulence regulatory network. Independent mutations therefore appeared during experimental evolution in the evolved clones, on a crucial node of this network, to favor adaptation to host vascular tissues through regulatory and metabolic rewiring.

Adaptive Decentralized Control

DTIC Science & Technology

1985-04-01

and implementation of the decentralized controllers. It raises, however, many difficult questions regarding the conditions under which such a scheme ...adaptive controller, and a general form of the model reference adaptive controller (4]. We believe that this work represents a significant advance in the...Comparing the adaptive system with the tuned system results in the development of a generic adaptive error system. Passivity theory was used to derive

Adaptive Control of Linear Modal Systems Using Residual Mode Filters and a Simple Disturbance Estimator

NASA Technical Reports Server (NTRS)

Balas, Mark; Frost, Susan

2012-01-01

Flexible structures containing a large number of modes can benefit from adaptive control techniques which are well suited to applications that have unknown modeling parameters and poorly known operating conditions. In this paper, we focus on a direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend our adaptive control theory to accommodate troublesome modal subsystems of a plant that might inhibit the adaptive controller. In some cases the plant does not satisfy the requirements of Almost Strict Positive Realness. Instead, there maybe be a modal subsystem that inhibits this property. This section will present new results for our adaptive control theory. We will modify the adaptive controller with a Residual Mode Filter (RMF) to compensate for the troublesome modal subsystem, or the Q modes. Here we present the theory for adaptive controllers modified by RMFs, with attention to the issue of disturbances propagating through the Q modes. We apply the theoretical results to a flexible structure example to illustrate the behavior with and without the residual mode filter.

Nitric Oxide Signaling in Hypergravity-Induced Neuronal Plasticity

NASA Technical Reports Server (NTRS)

Holstein, Gay R.

2003-01-01

The goal of this research project was to identify the neurons and circuits in the vestibular nuclei and nucleus prepositus hypoglossi that utilize nitric oxide (NO) for intercellular signaling during gravity-induced plasticity. This objective was pursued using histochemical and immunocytochemical approaches to localize NO-producing neurons and characterize the fine morphology of the cells in ground-based studies of normal rats, rats adapted to hypergravity, and rats adapted to hypergravity and then re-adapted to the 1G environment. NO-producing neurons were identified and studied using four methodologies: i) immunocytochemistry employing polyclonal antibodies directed against neuronal nitric oxide synthase (nNOS), to provide an indication of the capacity of a cell for NO production; ii) immunocytochemistry employing a monoclonal antibody directed against L-citrulline, to provide an indirect index of the enzyme's activity; iii) histochemistry based on the NADPH-diaphorase reaction, for fuI1 cytological visualization of neurons; and iv) double immunofluorescence to co-localize nNOS and L-citrulline in individual vestibular nuclei (VN) and neurons.

Evolutionary advantages of adaptive rewarding

NASA Astrophysics Data System (ADS)

Szolnoki, Attila; Perc, Matjaž

2012-09-01

Our well-being depends on both our personal success and the success of our society. The realization of this fact makes cooperation an essential trait. Experiments have shown that rewards can elevate our readiness to cooperate, but since giving a reward inevitably entails paying a cost for it, the emergence and stability of such behavior remains elusive. Here we show that allowing for the act of rewarding to self-organize in dependence on the success of cooperation creates several evolutionary advantages that instill new ways through which collaborative efforts are promoted. Ranging from indirect territorial battle to the spontaneous emergence and destruction of coexistence, phase diagrams and the underlying spatial patterns reveal fascinatingly rich social dynamics that explain why this costly behavior has evolved and persevered. Comparisons with adaptive punishment, however, uncover an Achilles heel of adaptive rewarding, coming from over-aggression, which in turn hinders optimal utilization of network reciprocity. This may explain why, despite its success, rewarding is not as firmly embedded into our societal organization as punishment.

Flow effects on benthic stream invertebrates and ecological processes

NASA Astrophysics Data System (ADS)

Koprivsek, Maja; Brilly, Mitja

2010-05-01

Flow is the main abiotic factor in the streams. Flow affects the organisms in many direct and indirect ways. The organisms are directly affected by various hydrodynamic forces and mass transfer processes like drag forces, drift, shear stress, food and gases supply and washing metabolites away. Indirect effects on the organisms are determining and distribution of the particle size and structure of the substrate and determining the morphology of riverbeds. Flow does not affect only on individual organism, but also on many ecological effects. To expose just the most important: dispersal of the organisms, habitat use, resource acquisition, competition and predator-prey interactions. Stream invertebrates are adapted to the various flow conditions in many kinds of way. Some of them are avoiding the high flow with living in a hyporeic zone, while the others are adapted to flow with physical adaptations (the way of feeding, respiration, osmoregulation and resistance to draught), morphological adaptations (dorsoventrally flattened shape of organism, streamlined shape of organism, heterogeneous suckers, silk, claws, swimming hair, bristles and ballast gravel) or with behaviour. As the flow characteristics in a particular stream vary over a broad range of space and time scales, it is necessary to measure accurately the velocity in places where the organisms are present to determine the actual impact of flow on aquatic organisms. By measuring the mean flow at individual vertical in a single cross-section, we cannot get any information about the velocity situation close to the bottom of the riverbed where the stream invertebrates are living. Just measuring the velocity near the bottom is a major problem, as technologies for measuring the velocity and flow of natural watercourses is not adapted to measure so close to the bottom. New researches in the last two decades has shown that the thickness of laminar border layer of stones in the stream is only a few 100 micrometers, what is not enough to make a shelter for stream invertebrates. It serves as a shelter only for microorganisms, but the stream invertebrates have to avoid the swift flow or adapt to flow with adaptations described above. To understand what conditions are subject to aquatic organisms and how to adapt, it is essential. Both, knowledge of fluid dynamics in natural watercourses and ecology are needed to understand to what conditions the stream invertebrates are exposed and how they cope with them. Some investigations of near bed flow will be performed on the Glinšica stream. The acoustic Doppler velocimeter SonTek will be adapted to measure so close to the bed as possible. It is expected we should be able to measure the velocities just 0,5 cm above the bed surface. We intend to measure the velocities on a natural and on a regulated reach and then compare the results.

Pupil Diameter Tracks the Exploration-Exploitation Trade-off during Analogical Reasoning and Explains Individual Differences in Fluid Intelligence.

PubMed

Hayes, Taylor R; Petrov, Alexander A

2016-02-01

The ability to adaptively shift between exploration and exploitation control states is critical for optimizing behavioral performance. Converging evidence from primate electrophysiology and computational neural modeling has suggested that this ability may be mediated by the broad norepinephrine projections emanating from the locus coeruleus (LC) [Aston-Jones, G., & Cohen, J. D. An integrative theory of locus coeruleus-norepinephrine function: Adaptive gain and optimal performance. Annual Review of Neuroscience, 28, 403-450, 2005]. There is also evidence that pupil diameter covaries systematically with LC activity. Although imperfect and indirect, this link makes pupillometry a useful tool for studying the locus coeruleus norepinephrine system in humans and in high-level tasks. Here, we present a novel paradigm that examines how the pupillary response during exploration and exploitation covaries with individual differences in fluid intelligence during analogical reasoning on Raven's Advanced Progressive Matrices. Pupillometry was used as a noninvasive proxy for LC activity, and concurrent think-aloud verbal protocols were used to identify exploratory and exploitative solution periods. This novel combination of pupillometry and verbal protocols from 40 participants revealed a decrease in pupil diameter during exploitation and an increase during exploration. The temporal dynamics of the pupillary response was characterized by a steep increase during the transition to exploratory periods, sustained dilation for many seconds afterward, and followed by gradual return to baseline. Moreover, the individual differences in the relative magnitude of pupillary dilation accounted for 16% of the variance in Advanced Progressive Matrices scores. Assuming that pupil diameter is a valid index of LC activity, these results establish promising preliminary connections between the literature on locus coeruleus norepinephrine-mediated cognitive control and the literature on analogical reasoning and fluid intelligence.

Biological control agents elevate hantavirus by subsidizing deer mouse populations.

PubMed

Pearson, Dean E; Callaway, Ragan M

2006-04-01

Biological control of exotic invasive plants using exotic insects is practiced under the assumption that biological control agents are safe if they do not directly attack non-target species. We tested this assumption by evaluating the potential for two host-specific biological control agents (Urophora spp.), widely established in North America for spotted knapweed (Centaurea maculosa) control, to indirectly elevate Sin Nombre hantavirus by providing food subsidies to populations of deer mice (Peromyscus maniculatus), the primary reservoir for the virus. We show that seropositive deer mice (mice testing positive for hantavirus) were over three times more abundant in the presence of the biocontrol food subsidy. Elevating densities of seropositive mice may increase risk of hantavirus infection in humans and significantly alter hantavirus ecology. Host specificity alone does not ensure safe biological control. To minimize indirect risks to non-target species, biological control agents must suppress pest populations enough to reduce their own numbers.

Adaptive functioning and behaviour problems in relation to level of education in children and adolescents with intellectual disability.

PubMed

de Bildt, A; Sytema, S; Kraijer, D; Sparrow, S; Minderaa, R

2005-09-01

The interrelationship between adaptive functioning, behaviour problems and level of special education was studied in 186 children with IQs ranging from 61 to 70. The objective was to increase the insight into the contribution of adaptive functioning and general and autistic behaviour problems to the level of education in children with intellectual disability (ID). Children from two levels of special education in the Netherlands were compared with respect to adaptive functioning [Vineland Adaptive Behavior Scales (VABS)], general behaviour problems [Child Behavior Checklist (CBCL)] and autistic behaviour problems [Autism Behavior Checklist (ABC)]. The effect of behaviour problems on adaptive functioning, and the causal relationships between behaviour problems, adaptive functioning and level of education were investigated. Children in schools for mild learning problems had higher VABS scores, and lower CBCL and ABC scores. The ABC had a significant effect on the total age equivalent of the VABS in schools for severe learning problems, the CBCL in schools for mild learning problems. A direct effect of the ABC and CBCL total scores on the VABS age equivalent was found, together with a direct effect of the VABS age equivalent on level of education and therefore an indirect effect of ABC and CBCL on level of education. In the children with the highest level of mild ID, adaptive functioning seems to be the most important factor that directly influences the level of education that a child attends. Autistic and general behaviour problems directly influence the level of adaptive functioning. Especially, autistic problems seem to have such a restrictive effect on the level of adaptive functioning that children do not reach the level of education that would be expected based on IQ. Clinical implications are discussed.

Recovery Act : Heterogeneous Feed Biorefinery Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schofield, Richard

2015-03-15

To overcome the hurdles associated with introducing a new technology, Enerkem applied to the US DOE for grant assistance with its Pontotoc, Mississippi, biorefinery under the DOE’s Demonstration of Integrated Biorefinery Operations FOA. Consistent with Enerkem’s strategic approach, the project proposed uses post sorted municipal solid waste blended with other forest residue. The proposed biorefinery is to be located within the boundaries of a working landfill, thus simplifying many aspects of environmental permitting while also reducing feedstock acquisition and transportation costs. An economic impact analysis was conducted using an adaptation of the US Department of Energy’s JEDI (Jobs and Economicmore » Development Impact) model for an ethanol-producing biorefinery. The JEDI model, which does not have a thermochemical processing option, had to be configured to reflect a biomass feedstock and was thus adapted by Enerkem to account for the unique feedstock requirements and operations of the Project. According to this model, development, construction, and 2 years of operation of the biorefinery require an investment of approximately $140 million. Also, a construction period of 18 months will create significant direct and indirect employment. Indirect employment includes steel manufacturers, construction materials manufacturers, material shipping, equipment manufacturers and fabrication, etc. During the construction phase of the Project, 210 total jobs are expected to be created, including 145 direct jobs and 72 indirect or induced jobs. During the operating period, 131 jobs would be created, 95 of which are direct. It is anticipated that the project will create at least 10 new jobs (included in the above figures and in addition to the JEDI data) in the sorting and recycling sector, since the project will require operations in sorting MSW since valuable ferrous, nonferrous and recyclable plastic materials will be sorted from MSW as part of the process that isolates MSW-derived biomass.« less

An adaptive Cartesian control scheme for manipulators

NASA Technical Reports Server (NTRS)

Seraji, H.

1987-01-01

A adaptive control scheme for direct control of manipulator end-effectors to achieve trajectory tracking in Cartesian space is developed. The control structure is obtained from linear multivariable theory and is composed of simple feedforward and feedback controllers and an auxiliary input. The direct adaptation laws are derived from model reference adaptive control theory and are not based on parameter estimation of the robot model. The utilization of feedforward control and the inclusion of auxiliary input are novel features of the present scheme and result in improved dynamic performance over existing adaptive control schemes. The adaptive controller does not require the complex mathematical model of the robot dynamics or any knowledge of the robot parameters or the payload, and is computationally fast for online implementation with high sampling rates.

Intelligent neural network and fuzzy logic control of industrial and power systems

NASA Astrophysics Data System (ADS)

Kuljaca, Ognjen

The main role played by neural network and fuzzy logic intelligent control algorithms today is to identify and compensate unknown nonlinear system dynamics. There are a number of methods developed, but often the stability analysis of neural network and fuzzy control systems was not provided. This work will meet those problems for the several algorithms. Some more complicated control algorithms included backstepping and adaptive critics will be designed. Nonlinear fuzzy control with nonadaptive fuzzy controllers is also analyzed. An experimental method for determining describing function of SISO fuzzy controller is given. The adaptive neural network tracking controller for an autonomous underwater vehicle is analyzed. A novel stability proof is provided. The implementation of the backstepping neural network controller for the coupled motor drives is described. Analysis and synthesis of adaptive critic neural network control is also provided in the work. Novel tuning laws for the system with action generating neural network and adaptive fuzzy critic are given. Stability proofs are derived for all those control methods. It is shown how these control algorithms and approaches can be used in practical engineering control. Stability proofs are given. Adaptive fuzzy logic control is analyzed. Simulation study is conducted to analyze the behavior of the adaptive fuzzy system on the different environment changes. A novel stability proof for adaptive fuzzy logic systems is given. Also, adaptive elastic fuzzy logic control architecture is described and analyzed. A novel membership function is used for elastic fuzzy logic system. The stability proof is proffered. Adaptive elastic fuzzy logic control is compared with the adaptive nonelastic fuzzy logic control. The work described in this dissertation serves as foundation on which analysis of particular representative industrial systems will be conducted. Also, it gives a good starting point for analysis of learning abilities of adaptive and neural network control systems, as well as for the analysis of the different algorithms such as elastic fuzzy systems.

Regional water quality patterns in an alluvial aquifer: direct and indirect influences of rivers.

PubMed

Baillieux, A; Campisi, D; Jammet, N; Bucher, S; Hunkeler, D

2014-11-15

The influence of rivers on the groundwater quality in alluvial aquifers can be twofold: direct and indirect. Rivers can have a direct influence via recharge and an indirect one by controlling the distribution of fine-grained, organic-carbon rich flood deposits that induce reducing conditions. These direct and indirect influences were quantified for a large alluvial aquifer on the Swiss Plateau (50km(2)) in interaction with an Alpine river using nitrate as an example. The hydrochemistry and stable isotope composition of water were characterized using a network of 115 piezometers and pumping stations covering the entire aquifer. Aquifer properties, land use and recharge zones were evaluated as well. This information provided detailed insight into the factors that control the spatial variability of groundwater quality. Three main factors were identified: (1) diffuse agricultural pollution sources; (2) dilution processes resulting from river water infiltrations, revealed by the δ(18)OH2O and δ(2)HH2O contents of groundwater; and (3) denitrification processes, controlled by the spatial variability of flood deposits governed by fluvial depositional processes. It was possible to quantify the dependence of the nitrate concentration on these three factors at any sampling point of the aquifer using an end-member mixing model, where the average nitrate concentration in recharge from the agricultural area was evaluated at 52mg/L, and the nitrate concentration of infiltrating river at approximately 6mg/L. The study shows the importance of considering the indirect and direct impacts of rivers on alluvial aquifers and provides a methodological framework to evaluate aquifer scale water quality patterns. Copyright © 2014 Elsevier B.V. All rights reserved.

Numerical investigation of CAI Combustion in the Opposed- Piston Engine with Direct and Indirect Water Injection

NASA Astrophysics Data System (ADS)

Pyszczek, R.; Mazuro, P.; Teodorczyk, A.

2016-09-01

This paper is focused on the CAI combustion control in a turbocharged 2-stroke Opposed-Piston (OP) engine. The barrel type OP engine arrangement is of particular interest for the authors because of its robust design, high mechanical efficiency and relatively easy incorporation of a Variable Compression Ratio (VCR). The other advantage of such design is that combustion chamber is formed between two moving pistons - there is no additional cylinder head to be cooled which directly results in an increased thermal efficiency. Furthermore, engine operation in a Controlled Auto-Ignition (CAI) mode at high compression ratios (CR) raises a possibility of reaching even higher efficiencies and very low emissions. In order to control CAI combustion such measures as VCR and water injection were considered for indirect ignition timing control. Numerical simulations of the scavenging and combustion processes were performed with the 3D CFD multipurpose AVL Fire solver. Numerous cases were calculated with different engine compression ratios and different amounts of directly and indirectly injected water. The influence of the VCR and water injection on the ignition timing and engine performance was determined and their application in the real engine was discussed.

Clinical performance of direct versus indirect composite restorations in posterior teeth: A systematic review.

PubMed

Azeem, Rubeena Abdul; Sureshbabu, Nivedhitha Malli

2018-01-01

Composite resin, serves as esthetic alternative to amalgam and cast restorations. Posterior teeth can be restored using direct or indirect composite restorations. The selection between direct and indirect technique is a clinically challenging decision-making process. Most important influencing factor is the amount of remaining tooth substance. The aim of this systematic review was to compare the clinical performance of direct versus indirect composite restorations in posterior teeth. The databases searched included PubMed CENTRAL (until July 2015), Medline, and Cochrane Database of Systematic Reviews. The bibliographies of clinical studies and reviews identified in the electronic search were analyzed to identify studies which were published outside the electronically searched journals. The primary outcome measure was evaluation of the survival of direct and indirect composite restorations in posterior teeth. This review included thirteen studies in which clinical performance of various types of direct and indirect composite restorations in posterior teeth were compared. Out of the thirteen studies which were included seven studies had a high risk of bias and five studies had a moderate risk of bias. One study having a low risk of bias, concluded that there was no significant difference between direct and indirect technique. However, the available evidence revealed inconclusive results. Further research should focus on randomized controlled trials with long term follow-up to give concrete evidence on the clinical performce of direct and indirect composite restorations.

Adaptive pseudolinear compensators of dynamic characteristics of automatic control systems

NASA Astrophysics Data System (ADS)

Skorospeshkin, M. V.; Sukhodoev, M. S.; Timoshenko, E. A.; Lenskiy, F. V.

2016-04-01

Adaptive pseudolinear gain and phase compensators of dynamic characteristics of automatic control systems are suggested. The automatic control system performance with adaptive compensators has been explored. The efficiency of pseudolinear adaptive compensators in the automatic control systems with time-varying parameters has been demonstrated.

Design of Low Complexity Model Reference Adaptive Controllers

NASA Technical Reports Server (NTRS)

Hanson, Curt; Schaefer, Jacob; Johnson, Marcus; Nguyen, Nhan

2012-01-01

Flight research experiments have demonstrated that adaptive flight controls can be an effective technology for improving aircraft safety in the event of failures or damage. However, the nonlinear, timevarying nature of adaptive algorithms continues to challenge traditional methods for the verification and validation testing of safety-critical flight control systems. Increasingly complex adaptive control theories and designs are emerging, but only make testing challenges more difficult. A potential first step toward the acceptance of adaptive flight controllers by aircraft manufacturers, operators, and certification authorities is a very simple design that operates as an augmentation to a non-adaptive baseline controller. Three such controllers were developed as part of a National Aeronautics and Space Administration flight research experiment to determine the appropriate level of complexity required to restore acceptable handling qualities to an aircraft that has suffered failures or damage. The controllers consist of the same basic design, but incorporate incrementally-increasing levels of complexity. Derivations of the controllers and their adaptive parameter update laws are presented along with details of the controllers implementations.

Family influences on the development of aggression and violence.

PubMed

Labella, Madelyn H; Masten, Ann S

2018-02-01

Recent research confirms that many of the most salient risk and protective factors for the development of aggression and violence reside in the family system. Family-based risks begin before birth, encompassing genetic and epigenetic processes. Contextual stressors (e.g., poverty, conflict) may impact development directly or indirectly through disrupted parenting behavior, including high negativity, low warmth, harshness, and exposure to violence. The family can also serve as a powerful adaptive system counteracting the risk of aggression and violence. Parents can promote healthy behavioral development through warmth, structure, and prosocial values, as well as by fostering adaptive resources in the child and community. Successful interventions often reduce aggression and violence by supporting parents and families. Recent insights and future directions for research and practice are discussed. Copyright © 2017. Published by Elsevier Ltd.

Molecular aspects of stress-gene regulation during spaceflight

NASA Technical Reports Server (NTRS)

Paul, Anna-Lisa; Ferl, Robert J.

2002-01-01

Spaceflight-associated stress has been the topic of investigation since the first terrestrial organisms were exposed to this unique environment. Organisms that evolved under the selection pressures of earth-normal environments can perceive spaceflight as a stress, either directly because gravity influences an intrinsic biological process, or indirectly because of secondary effects imparted by spaceflight upon environmental conditions. Different organisms and even different organs within an organism adapt to a spaceflight environment with a diversity of tactics. Plants are keenly sensitive to gravity for directed development, and are also sensitive to other stresses associated with closed-system spaceflight environments. Within the past decade, the tools of molecular biology have begun to provide a sophisticated evaluation of spaceflight-associated stress and the genetic responses that accompany metabolic adaptation to spaceflight.

Climate change: could it help develop 'adaptive expertise'?

PubMed

Bell, Erica; Horton, Graeme; Blashki, Grant; Seidel, Bastian M

2012-05-01

Preparing health practitioners to respond to the rising burden of disease from climate change is emerging as a priority in health workforce policy and planning. However, this issue is hardly represented in the medical education research. The rapidly evolving wide range of direct and indirect consequences of climate change will require health professionals to have not only broad content knowledge but also flexibility and responsiveness to diverse regional conditions as part of complex health problem-solving and adaptation. It is known that adaptive experts may not necessarily be quick at solving familiar problems, but they do creatively seek to better solve novel problems. This may be the result of an acquired approach to practice or a pathway that can be fostered by learning environments. It is also known that building adaptive expertise in medical education involves putting students on a learning pathway that requires them to have, first, the motivation to innovatively problem-solve and, second, exposure to diverse content material, meaningfully presented. Including curriculum content on the health effects of climate change could help meet these two conditions for some students at least. A working definition and illustrative competencies for adaptive expertise for climate change, as well as examples of teaching and assessment approaches extrapolated from rural curricula, are provided.

Innate and adaptive immunity at Mucosal Surfaces of the Female Reproductive Tract: Stratification and Integration of Immune Protection against the Transmission of Sexually Transmitted Infections

PubMed Central

Hickey, DK; Patel, MV; Fahey, JV; Wira, CR

2011-01-01

This review examines the multiple levels of pre-existing immunity in the upper and lower female reproductive tract. In addition, we highlight the need for further research of innate and adaptive immune protection of mucosal surfaces in the female reproductive tract. Innate mechanisms include the mucus lining, a tight epithelial barrier and the secretion of antimicrobial peptides and cytokines by epithelial and innate immune cells. Stimulation of the innate immune system also serves to bridge the adaptive arm resulting in the generation of pathogen-specific humoral and cell-mediated immunity. Less understood are the multiple components that act in a coordinated way to provide a network of ongoing protection. Innate and adaptive immunity in the human female reproductive tract are influenced by the stage of menstrual cycle and are directly regulated by the sex steroid hormones, progesterone and estradiol. Furthermore, the effect of hormones on immunity is mediated both directly on immune and epithelial cells and indirectly by stimulating growth factor secretion from stromal cells. The goal of this review is to focus on the diverse aspects of the innate and adaptive immune systems that contribute to a unique network of protection throughout the female reproductive tract. PMID:21353708

Influence of a peracetic acid-based immersion on indirect composite resin.

PubMed

Samuel, Susana Maria Werner; Fracaro, Gisele Baggio; Collares, Fabrício Mezzomo; Leitune, Vicente Castelo Branco; Campregher, Ulisses Bastos

2011-06-01

The aim of this study was to evaluate the influence of immersion in a 0.2% peracetic acid-based disinfectant on the three-point flexural strength, water sorption and water solubility of an indirect composite resin. Specimens were produced according to ISO 4049:2000 specifications and were divided in two groups: Control group, with no disinfection and Disinfected group, with three 10 min immersions in the peracetic acid intercalated with 10 min immersions in sterile distilled water. All evaluations were conducted in compliance with ISO specifications. Three-point flexural strength, water sorption and solubility of indirect composite resin before and after immersion showed no statistical significant differences (p > 0.05) and met ISO standard requirements. Immersion in peracetic acid solution showed no influence in indirect composite resin tested properties.

Relationship between boys' normative beliefs about aggression and their physical, verbal, and indirect aggressive behaviors.

PubMed

Lim, Si Huan; Ang, Rebecca P

2009-01-01

This study examined the contribution of general normative beliefs about aggression and specific normative beliefs about retaliatory aggression in predicting physical, verbal, and indirect aggressive behaviors. Two hundred and forty-nine Grade 4 and Grade 5 boys completed the Normative Beliefs about Aggression Scale (NOBAGS) and provided self-reports on the frequency of their physical, verbal, and indirect aggressive behaviors. A series of hierarchical multiple regression analyses revealed that general normative beliefs about aggression contributed significantly in predicting all three types of aggressive behaviors. When general normative beliefs about aggression were controlled for, specific normative beliefs about retaliatory aggression against males but not specific normative beliefs about retaliatory aggression against females, contributed significantly to predict physical, verbal, and indirect aggressive behaviors. Implications for intervention programs are discussed.

Direct and Indirect Peer Socialization of Adolescent Nonsuicidal Self-Injury

PubMed Central

Giletta, Matteo; Burk, William J.; Scholte, Ron H. J.; Engels, Rutger C. M. E.; Prinstein, Mitchell J.

2015-01-01

This study examined direct and indirect forms of peer socialization of non-suicidal self-injury (NSSI) in adolescent friendship networks. Data were collected among 348 adolescents (55% females; Mage = 15.02 years; SD = 0.53) at 4 assessment waves. Stochastic actor-based models revealed no evidence for direct socialization of NSSI: adolescents whose friends reported higher NSSI did not increase their NSSI over time. However, indirect forms of socialization were found. After controlling for direct socialization and selection effects, friends’ depressive symptoms predicted changes in male and female adolescents’ NSSI and friends’ impulsivity predicted changes in male adolescents’ NSSI. Findings highlight the importance of extending peer influence research beyond the classical “modeling” paradigm by providing evidence that peers may indirectly socialize adolescents’ NSSI. PMID:26412955

Riboregulation of the bacterial actin-homolog MreB by DsrA small noncoding RNA.

PubMed

Cayrol, Bastien; Fortas, Emilie; Martret, Claire; Cech, Grzegorz; Kloska, Anna; Caulet, Stephane; Barbet, Marion; Trépout, Sylvain; Marco, Sergio; Taghbalout, Aziz; Busi, Florent; Wegrzyn, Grzegorz; Arluison, Véronique

2015-01-01

The bacterial actin-homolog MreB is a key player in bacterial cell-wall biosynthesis and is required for the maintenance of the rod-like morphology of Escherichia coli. However, how MreB cellular levels are adjusted to growth conditions is poorly understood. Here, we show that DsrA, an E. coli small noncoding RNA (sRNA), is involved in the post-transcriptional regulation of mreB. DsrA is required for the downregulation of MreB cellular concentration during environmentally induced slow growth-rates, mainly growth at low temperature and during the stationary phase. DsrA interacts in an Hfq-dependent manner with the 5' region of mreB mRNA, which contains signals for translation initiation and thereby affects mreB translation and stability. Moreover, as DsrA is also involved in the regulation of two transcriptional regulators, σ(S) and the nucleoid associated protein H-NS, which negatively regulate mreB transcription, it also indirectly contributes to mreB transcriptional down-regulation. By using quantitative analyses, our results evidence the complexity of this regulation and the tangled interplay between transcriptional and post-transcriptional control. As transcription factors and sRNA-mediated post-transcriptional regulators use different timescales, we propose that the sRNA pathway helps to adapt to changes in temperature, but also indirectly mediates long-term regulation of MreB concentration. The tight regulation and fine-tuning of mreB gene expression in response to cellular stresses is discussed in regard to the effect of the MreB protein on cell elongation.

Development of peptide and protein based radiopharmaceuticals.

PubMed

Wynendaele, Evelien; Bracke, Nathalie; Stalmans, Sofie; De Spiegeleer, Bart

2014-01-01

Radiolabelled peptides and proteins have recently gained great interest as theranostics, due to their numerous and considerable advantages over small (organic) molecules. Developmental procedures of these radiolabelled biomolecules start with the radiolabelling process, greatly defined by the amino acid composition of the molecule and the radionuclide used. Depending on the radionuclide selection, radiolabelling starting materials are whether or not essential for efficient radiolabelling, resulting in direct or indirect radioiodination, radiometal-chelate coupling, indirect radiofluorination or (3)H/(14)C-labelling. Before preclinical investigations are performed, quality control analyses of the synthesized radiopharmaceutical are recommended to eliminate false positive or negative functionality results, e.g. changed receptor binding properties due to (radiolabelled) impurities. Therefore, radionuclidic, radiochemical and chemical purity are investigated, next to the general peptide attributes as described in the European and the United States Pharmacopeia. Moreover, in vitro and in vivo stability characteristics of the peptides and proteins also need to be explored, seen their strong sensitivity to proteinases and peptidases, together with radiolysis and trans-chelation phenomena of the radiopharmaceuticals. In vitro biomedical characterization of the radiolabelled peptides and proteins is performed by saturation, kinetic and competition binding assays, analyzing KD, Bmax, kon, koff and internalization properties, taking into account the chemical and metabolic stability and adsorption events inherent to peptides and proteins. In vivo biodistribution can be adapted by linker, chelate or radionuclide modifications, minimizing normal tissue (e.g. kidney and liver) radiation, and resulting in favorable dosimetry analyses. Finally, clinical trials are initiated, eventually leading to the marketing of radiolabelled peptides and proteins for PET/SPECT-imaging and therapy of different clinical diseases.

Examining a conceptual model of parental nurturance, parenting practices and physical activity among 5–6 year olds

PubMed Central

Sebire, Simon J.; Jago, Russell; Wood, Lesley; Thompson, Janice L.; Zahra, Jezmond; Lawlor, Deborah A.

2016-01-01

Rationale Parenting is an often-studied correlate of children's physical activity, however there is little research examining the associations between parenting styles, practices and the physical activity of younger children. Objective This study aimed to investigate whether physical activity-based parenting practices mediate the association between parenting styles and 5–6 year-old children's objectively-assessed physical activity. Methods 770 parents self-reported parenting style (nurturance and control) and physical activity-based parenting practices (logistic and modeling support). Their 5–6 year old child wore an accelerometer for five days to measure moderate-to-vigorous physical activity (MVPA). Linear regression was used to examine direct and indirect (mediation) associations. Data were collected in the United Kingdom in 2012/13 and analyzed in 2014. Results Parent nurturance was positively associated with provision of modeling (adjusted unstandardized coefficient, β = 0.11; 95% CI = 0.02, 0.21) and logistic support (β = 0.14; 0.07, 0.21). Modeling support was associated with greater child MVPA (β = 2.41; 0.23, 4.60) and a small indirect path from parent nurturance to child's MVPA was identified (β = 0.27; 0.04, 0.70). Conclusions Physical activity-based parenting practices are more strongly associated with 5–6 year old children's MVPA than parenting styles. Further research examining conceptual models of parenting is needed to understand in more depth the possible antecedents to adaptive parenting practices beyond parenting styles. PMID:26647364

Role of linguistic skills in fifth-grade mathematics.

PubMed

Kleemans, Tijs; Segers, Eliane; Verhoeven, Ludo

2018-03-01

The current study investigated the direct and indirect relations between basic linguistic skills (i.e., phonological skills and grammatical ability) and advanced linguistic skills (i.e., academic vocabulary and verbal reasoning), on the one hand, and fifth-grade mathematics (i.e., arithmetic, geometry, and fractions), on the other, taking working memory and general intelligence into account and controlling for socioeconomic status, age, and gender. The results showed the basic linguistic representations of 167 fifth graders to be indirectly related to their geometric and fraction skills via arithmetic. Furthermore, advanced linguistic skills were found to be directly related to geometry and fractions after controlling for arithmetic. It can be concluded that linguistic skills directly and indirectly relate to mathematical ability in the upper grades of primary education, which highlights the importance of paying attention to such skills in the school curriculum. Copyright © 2017 Elsevier Inc. All rights reserved.

Alien plant dynamics following fire in mediterranean-climate California shrublands

USGS Publications Warehouse

Keeley, J.E.; Baer-Keeley, M.; Fotheringham, C.J.

2005-01-01

Over 75 species of alien plants were recorded during the first five years after fire in southern California shrublands, most of which were European annuals. Both cover and richness of aliens varied between years and plant association. Alien cover was lowest in the first postfire year in all plant associations and remained low during succession in chaparral but increased in sage scrub. Alien cover and richness were significantly correlated with year (time since disturbance) and with precipitation in both coastal and interior sage scrub associations. Hypothesized factors determining alien dominance were tested with structural equation modeling. Models that included nitrogen deposition and distance from the coast were not significant, but with those variables removed we obtained a significant model that gave an R2 = 0.60 for the response variable of fifth year alien dominance. Factors directly affecting alien dominance were (1) woody canopy closure and (2) alien seed banks. Significant indirect effects were (3) fire intensity, (4) fire history, (5) prefire stand structure, (6) aridity, and (7) community type. According to this model the most critical factor influencing aliens is the rapid return of the shrub and subshrub canopy. Thus, in these communities a single functional type (woody plants) appears to the most critical element controlling alien invasion and persistence. Fire history is an important indirect factor because it affects both prefire stand structure and postfire alien seed banks. Despite being fire-prone ecosystems, these shrublands are not adapted to fire per se, but rather to a particular fire regime. Alterations in the fire regime produce a very different selective environment, and high fire frequency changes the selective regime to favor aliens. This study does not support the widely held belief that prescription burning is a viable management practice for controlling alien species on semiarid landscapes. ?? 2005 by the Ecological Society of America.

Intelligent control of non-linear dynamical system based on the adaptive neurocontroller

NASA Astrophysics Data System (ADS)

Engel, E.; Kovalev, I. V.; Kobezhicov, V.

2015-10-01

This paper presents an adaptive neuro-controller for intelligent control of non-linear dynamical system. The formed as the fuzzy selective neural net the adaptive neuro-controller on the base of system's state, creates the effective control signal under random perturbations. The validity and advantages of the proposed adaptive neuro-controller are demonstrated by numerical simulations. The simulation results show that the proposed controller scheme achieves real-time control speed and the competitive performance, as compared to PID, fuzzy logic controllers.

Real-time control of geometry and stiffness in adaptive structures

NASA Technical Reports Server (NTRS)

Ramesh, A. V.; Utku, S.; Wada, B. K.

1991-01-01

The basic theory is presented for the geometry, stiffness, and damping control of adaptive structures, with emphasis on adaptive truss structures. Necessary and sufficient conditions are given for stress-free geometry control in statically determinate and indeterminate adaptive discrete structures. Two criteria for selecting the controls are proposed, and their use in real-time control is illustrated by numerical simulation results. It is shown that the stiffness and damping control of adaptive truss structures for vibration suppression is possible by elongation and elongation rate dependent feedback forces from the active elements.

Experimental validation of tonal noise control from subsonic axial fans using flow control obstructions

NASA Astrophysics Data System (ADS)

Gérard, Anthony; Berry, Alain; Masson, Patrice; Gervais, Yves

2009-03-01

This paper presents the acoustic performance of a novel approach for the passive adaptive control of tonal noise radiated from subsonic fans. Tonal noise originates from non-uniform flow that causes circumferentially varying blade forces and gives rise to a considerably larger radiated dipolar sound at the blade passage frequency (BPF) and its harmonics compared to the tonal noise generated by a uniform flow. The approach presented in this paper uses obstructions in the flow to destructively interfere with the primary tonal noise arising from various flow conditions. The acoustic radiation of the obstructions is first demonstrated experimentally. Indirect on-axis acoustic measurements are used to validate the analytical prediction of the circumferential spectrum of the blade unsteady lift and related indicators generated by the trapezoidal and sinusoidal obstructions presented in Ref. [A. Gérard, A. Berry, P. Masson, Y. Gervais, Modelling of tonal noise control from subsonic axial fans using flow control obstructions, Journal of Sound and Vibration (2008), this issue, doi: 10.1016/j.jsv.2008.09.027.] and also by cylindrical obstructions used in the literature. The directivity and sound power attenuation are then given in free field for the control of the BPF tone generated by rotor/outlet guide vane (OGV) interaction and the control of an amplified BPF tone generated by the rotor/OGV interaction with an added triangular obstruction between two outlet guide vanes to enhance the primary non-uniform flow. Global control was demonstrated in free field, attenuation up to 8.4 dB of the acoustic power at BPF has been measured. Finally, the aerodynamic performances of the automotive fan used in this study are almost not affected by the presence of the control obstruction.

Optimal Control Modification for Time-Scale Separated Systems

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2012-01-01

Recently a new optimal control modification has been introduced that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. This modification is based on an optimal control formulation to minimize the L2 norm of the tracking error. The optimal control modification adaptive law results in a stable adaptation in the presence of a large adaptive gain. This study examines the optimal control modification adaptive law in the context of a system with a time scale separation resulting from a fast plant with a slow actuator. A singular perturbation analysis is performed to derive a modification to the adaptive law by transforming the original system into a reduced-order system in slow time. A model matching conditions in the transformed time coordinate results in an increase in the actuator command that effectively compensate for the slow actuator dynamics. Simulations demonstrate effectiveness of the method.

Adaptive control in the presence of unmodeled dynamics. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Rohrs, C. E.

1982-01-01

Stability and robustness properties of a wide class of adaptive control algorithms in the presence of unmodeled dynamics and output disturbances were investigated. The class of adaptive algorithms considered are those commonly referred to as model reference adaptive control algorithms, self-tuning controllers, and dead beat adaptive controllers, developed for both continuous-time systems and discrete-time systems. A unified analytical approach was developed to examine the class of existing adaptive algorithms. It was discovered that all existing algorithms contain an infinite gain operator in the dynamic system that defines command reference errors and parameter errors; it is argued that such an infinite gain operator appears to be generic to all adaptive algorithms, whether they exhibit explicit or implicit parameter identification. It is concluded that none of the adaptive algorithms considered can be used with confidence in a practical control system design, because instability will set in with a high probability.

Isoenergetic feeding of low carbohydrate-high fat diets does not increase brown adipose tissue thermogenic capacity in rats.

PubMed

Betz, Matthias J; Bielohuby, Maximilian; Mauracher, Brigitte; Abplanalp, William; Müller, Hans-Helge; Pieper, Korbinian; Ramisch, Juliane; Tschöp, Matthias H; Beuschlein, Felix; Bidlingmaier, Martin; Slawik, Marc

2012-01-01

Low-carbohydrate, high-fat (LC-HF) diets are popular for inducing weight loss in overweighed adults. Adaptive thermogenesis increased by specific effects of macronutrients on energy expenditure has been postulated to induce this weight loss. We studied brown adipose tissue (BAT) morphology and function following exposure to different LC-HF diets. Male Wistar rats were fed a standard control diet ad libitum or pair-fed isoenergetic amounts of three experimental diets for 4 weeks. The diets had the following macronutrient composition (% metabolizable energy: carbohydrates, fat, protein): control (64.3/16.7/19), LC-HF-low protein (LC-HF-LP, 1.7/92.8/5.5), LC-HF-normal-protein (LC-HF-NP, 2.2/78.7/19.1), and a high fat diet with carbohydrates ("high fat", 19.4/61.9/18.7). Body weight gain was reduced in all pair-fed experimental groups as compared to rats fed the control diet, with more pronounced effect in rats on LC-HF diets than on the high fat diet with carbohydrates. High fat diets increased expression of PGC1α and ADRB3 in BAT indicating higher SNS outflow. However, UCP1 mRNA expression and expression of UCP1 assessed by immunohistochemistry was not different between diet groups. In accordance, analysis of mitochondrial function in-vitro by extracellular flux analyser (Seahorse Bioscience) and measurement of inducible thermogenesis in vivo (primary endpoint), explored by indirect calorimetry following norepinephrine injection, did not show significant differences between groups. Histology of BAT revealed increased lipid droplet size in rats fed the high-fat diet and both LC-HF diets. All experimental diets upregulated expression of genes which are indicative for increased BAT activity. However, the functional measurements in vivo revealed no increase of inducible BAT thermogenesis. This indicates that lower body weight gain with LC-HF diets and a high fat diet in a pair-feeding setting is not caused by increased adaptive thermogenesis in BAT.

Interventions for preventing voice disorders in adults.

PubMed

Ruotsalainen, J H; Sellman, J; Lehto, L; Jauhiainen, M; Verbeek, J H

2007-10-17

Poor voice quality due to a voice disorder can lead to a reduced quality of life. In occupations where voice use is substantial it can lead to periods of absence from work. To evaluate the effectiveness of interventions to prevent voice disorders in adults. We searched MEDLINE (PubMed, 1950 to 2006), EMBASE (1974 to 2006), CENTRAL (The Cochrane Library, Issue 2 2006), CINAHL (1983 to 2006), PsychINFO (1967 to 2006), Science Citation Index (1986 to 2006) and the Occupational Health databases OSH-ROM (to 2006). The date of the last search was 05/04/06. Randomised controlled clinical trials (RCTs) of interventions evaluating the effectiveness of treatments to prevent voice disorders in adults. For work-directed interventions interrupted time series and prospective cohort studies were also eligible. Two authors independently extracted data and assessed trial quality. Meta-analysis was performed where appropriate. We identified two randomised controlled trials including a total of 53 participants in intervention groups and 43 controls. One study was conducted with teachers and the other with student teachers. Both trials were poor quality. Interventions were grouped into 1) direct voice training, 2) indirect voice training and 3) direct and indirect voice training combined.1) Direct voice training: One study did not find a significant decrease of the Voice Handicap Index for direct voice training compared to no intervention.2) Indirect voice training: One study did not find a significant decrease of the Voice Handicap Index for indirect voice training when compared to no intervention.3) Direct and indirect voice training combined: One study did not find a decrease of the Voice Handicap Index for direct and indirect voice training combined when compared to no intervention. The same study did however find an improvement in maximum phonation time (Mean Difference -3.18 sec; 95 % CI -4.43 to -1.93) for direct and indirect voice training combined when compared to no intervention. No work-directed studies were found. None of the studies found evaluated the effectiveness of prevention in terms of sick leave or number of diagnosed voice disorders. We found no evidence that either direct or indirect voice training or the two combined are effective in improving self-reported vocal functioning when compared to no intervention. The current practice of giving training to at-risk populations for preventing the development of voice disorders is therefore not supported by definitive evidence of effectiveness. Larger and methodologically better trials are needed with outcome measures that better reflect the aims of interventions.

Closing the Certification Gaps in Adaptive Flight Control Software

NASA Technical Reports Server (NTRS)

Jacklin, Stephen A.

2008-01-01

Over the last five decades, extensive research has been performed to design and develop adaptive control systems for aerospace systems and other applications where the capability to change controller behavior at different operating conditions is highly desirable. Although adaptive flight control has been partially implemented through the use of gain-scheduled control, truly adaptive control systems using learning algorithms and on-line system identification methods have not seen commercial deployment. The reason is that the certification process for adaptive flight control software for use in national air space has not yet been decided. The purpose of this paper is to examine the gaps between the state-of-the-art methodologies used to certify conventional (i.e., non-adaptive) flight control system software and what will likely to be needed to satisfy FAA airworthiness requirements. These gaps include the lack of a certification plan or process guide, the need to develop verification and validation tools and methodologies to analyze adaptive controller stability and convergence, as well as the development of metrics to evaluate adaptive controller performance at off-nominal flight conditions. This paper presents the major certification gap areas, a description of the current state of the verification methodologies, and what further research efforts will likely be needed to close the gaps remaining in current certification practices. It is envisioned that closing the gap will require certain advances in simulation methods, comprehensive methods to determine learning algorithm stability and convergence rates, the development of performance metrics for adaptive controllers, the application of formal software assurance methods, the application of on-line software monitoring tools for adaptive controller health assessment, and the development of a certification case for adaptive system safety of flight.

Anti-windup adaptive PID control design for a class of uncertain chaotic systems with input saturation.

PubMed

Tahoun, A H

2017-01-01

In this paper, the stabilization problem of actuators saturation in uncertain chaotic systems is investigated via an adaptive PID control method. The PID control parameters are auto-tuned adaptively via adaptive control laws. A multi-level augmented error is designed to account for the extra terms appearing due to the use of PID and saturation. The proposed control technique uses both the state-feedback and the output-feedback methodologies. Based on Lyapunov׳s stability theory, new anti-windup adaptive controllers are proposed. Demonstrative examples with MATLAB simulations are studied. The simulation results show the efficiency of the proposed adaptive PID controllers. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

More pain, more gain: Blocking the opioid system boosts adaptive cognitive control.

PubMed

van Steenbergen, Henk; Weissman, Daniel H; Stein, Dan J; Malcolm-Smith, Susan; van Honk, Jack

2017-06-01

The ability to adaptively increase cognitive control in response to cognitive challenges is crucial for goal-directed behavior. Recent findings suggest that aversive arousal triggers adaptive increases of control, but the neurochemical mechanisms underlying these effects remain unclear. Given the known contributions of the opioid system to hedonic states, we investigated whether blocking this system increases adaptive control modulations. To do so, we conducted a double-blind, placebo-controlled psychopharmacological study (n=52 females) involving a Stroop-like task. Specifically, we assessed the effect of naltrexone, an opioid blocker most selective to the mu-opioid system, on two measures of adaptive control that are thought to depend differentially on aversive arousal: post-error slowing and conflict adaptation. Consistent with our hypothesis, relative to placebo, naltrexone increased post-error slowing without influencing conflict adaptation. This finding not only supports the view that aversive arousal triggers adaptive control but also reveals a novel role for the opioid system in modulating such effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Adaptive Control of Non-Minimum Phase Modal Systems Using Residual Mode Filters2. Parts 1 and 2

NASA Technical Reports Server (NTRS)

Balas, Mark J.; Frost, Susan

2011-01-01

Many dynamic systems containing a large number of modes can benefit from adaptive control techniques, which are well suited to applications that have unknown parameters and poorly known operating conditions. In this paper, we focus on a direct adaptive control approach that has been extended to handle adaptive rejection of persistent disturbances. We extend this adaptive control theory to accommodate problematic modal subsystems of a plant that inhibit the adaptive controller by causing the open-loop plant to be non-minimum phase. We will modify the adaptive controller with a Residual Mode Filter (RMF) to compensate for problematic modal subsystems, thereby allowing the system to satisfy the requirements for the adaptive controller to have guaranteed convergence and bounded gains. This paper will be divided into two parts. Here in Part I we will review the basic adaptive control approach and introduce the primary ideas. In Part II, we will present the RMF methodology and complete the proofs of all our results. Also, we will apply the above theoretical results to a simple flexible structure example to illustrate the behavior with and without the residual mode filter.

Design of a Model Reference Adaptive Controller for an Unmanned Air Vehicle

NASA Technical Reports Server (NTRS)

Crespo, Luis G.; Matsutani, Megumi; Annaswamy, Anuradha M.

2010-01-01

This paper presents the "Adaptive Control Technology for Safe Flight (ACTS)" architecture, which consists of a non-adaptive controller that provides satisfactory performance under nominal flying conditions, and an adaptive controller that provides robustness under off nominal ones. The design and implementation procedures of both controllers are presented. The aim of these procedures, which encompass both theoretical and practical considerations, is to develop a controller suitable for flight. The ACTS architecture is applied to the Generic Transport Model developed by NASA-Langley Research Center. The GTM is a dynamically scaled test model of a transport aircraft for which a flight-test article and a high-fidelity simulation are available. The nominal controller at the core of the ACTS architecture has a multivariable LQR-PI structure while the adaptive one has a direct, model reference structure. The main control surfaces as well as the throttles are used as control inputs. The inclusion of the latter alleviates the pilot s workload by eliminating the need for cancelling the pitch coupling generated by changes in thrust. Furthermore, the independent usage of the throttles by the adaptive controller enables their use for attitude control. Advantages and potential drawbacks of adaptation are demonstrated by performing high fidelity simulations of a flight-validated controller and of its adaptive augmentation.

A Longitudinal Investigation of Direct and Indirect Links between Reading Skills in Kindergarten and Reading Comprehension in Tenth Grade

ERIC Educational Resources Information Center

Stanley, Christopher T.; Petscher, Yaacov; Catts, Hugh

2018-01-01

In this study, researchers examined the extent to which several fundamental measures of reading proficiency from kindergarten students (N = 3180) were linked to reading comprehension in tenth grade while controlling for third grade vocabulary and oral reading fluency. Analyses tested the direct and indirect relations between and among…

Controlling an indirect hot water heater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Capano, J.

The procedure for servicing a Dunkirk Empire indirect water heater is presented. In this particular case the serviceman found that a wire was loose on the aquastat on the tank. The serviceman checked the wire and the past and tightened the connection. This took care of the problem. A wiring diagram is presented for the home heating system and the hot water heater.

77 FR 3297 - Self-Regulatory Organizations; EDGA Exchange, Inc.; EDGX Exchange, Inc.; International Securities...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

... limitations would apply only for so long as NYSE Group directly or indirectly controls any NYSE U.S. Regulated... (``Deutsche B[ouml]rse''). NYSE Euronext owns 100% of the equity interest of NYSE Group, Inc., a Delaware corporation (``NYSE Group''), which in turn directly or indirectly owns (1) 100% of the equity interest of the...

Collateral Benefits of the Family Check-Up on Early Childhood School Readiness: Indirect Effects of Parents' Positive Behavior Support

ERIC Educational Resources Information Center

Lunkenheimer, Erika S.; Dishion, Thomas J.; Shaw, Daniel S.; Connell, Arin M.; Gardner, Frances; Wilson, Melvin N.; Skuban, Emily M.

2008-01-01

The authors examined the longitudinal effects of the Family Check-Up (FCU) on parents' positive behavior support and children's school readiness competencies in early childhood. It was hypothesized that the FCU would promote language skills and inhibitory control in children at risk for behavior problems as an indirect outcome associated with…

Teaching to Play Performing a Main Role -- Effective Method of Pretend Play Facilitation in Preschool-Age Children

ERIC Educational Resources Information Center

Gmitrova, Vlasta

2013-01-01

We compared the efficiency of teacher's direct and indirect intervention into pretend play. Three hundred sixty-eight kindergarten children and 92 qualified kindergarten teachers were involved in the study. In the control group, a teacher indirectly initiated a play, creating a playing corner adjusted to the theme of the pretend play and during…

[Estimation of economic costs for the care of patients with nosocomial pneumonia in a regional peruvian hospital, 2009-2011].

PubMed

Dámaso-Mata, Bernardo; Chirinos-Cáceres, Jesús; Menacho-Villafuerte, Luz

2016-06-01

To estimate and compare the economic costs for the care of patients with and without nosocomial pneumonia at Hospital II Huánuco EsSalud during 2009-2011, in Peru. This was a partial economic evaluation of paired cases and controls. A collection sheet was used. nosocomial pneumonia. direct health costs, direct non-health costs, indirect costs, occupation, age, comorbidities, sex, origin, and education level. A bivariate analysis was performed. Forty pairs of cases and controls were identified. These patients were hospitalized for >2 weeks and prescribed more than two antibiotics. The associated direct health costs included those for hospitalization, antibiotics, auxiliary examinations, specialized assessments, and other medications. The direct non-health costs and associated indirect costs included those for transportation, food, housing, foregone payroll revenue, foregone professional fee revenue, extra-institutional expenses, and payment to caregivers during hospitalization and by telephone. The direct health costs for nosocomial pneumonia patients were more than three times and the indirect costs were more than two times higher than those for the controls. Variables with the greatest impact on costs were identified.

Quaternion-based adaptive output feedback attitude control of spacecraft using Chebyshev neural networks.

PubMed

Zou, An-Min; Dev Kumar, Krishna; Hou, Zeng-Guang

2010-09-01

This paper investigates the problem of output feedback attitude control of an uncertain spacecraft. Two robust adaptive output feedback controllers based on Chebyshev neural networks (CNN) termed adaptive neural networks (NN) controller-I and adaptive NN controller-II are proposed for the attitude tracking control of spacecraft. The four-parameter representations (quaternion) are employed to describe the spacecraft attitude for global representation without singularities. The nonlinear reduced-order observer is used to estimate the derivative of the spacecraft output, and the CNN is introduced to further improve the control performance through approximating the spacecraft attitude motion. The implementation of the basis functions of the CNN used in the proposed controllers depends only on the desired signals, and the smooth robust compensator using the hyperbolic tangent function is employed to counteract the CNN approximation errors and external disturbances. The adaptive NN controller-II can efficiently avoid the over-estimation problem (i.e., the bound of the CNNs output is much larger than that of the approximated unknown function, and hence, the control input may be very large) existing in the adaptive NN controller-I. Both adaptive output feedback controllers using CNN can guarantee that all signals in the resulting closed-loop system are uniformly ultimately bounded. For performance comparisons, the standard adaptive controller using the linear parameterization of spacecraft attitude motion is also developed. Simulation studies are presented to show the advantages of the proposed CNN-based output feedback approach over the standard adaptive output feedback approach.

77 FR 35680 - Change in Bank Control Notices; Acquisitions of Shares of a Bank or Bank Holding Company

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-14

..., New York, New York 10045-0001: 1. Muhammad Habib, Zurich, Switzerland; to retain a controlling interest in Maham Beteiligungsgessellschaft AG, Zurich, Switzerland, and thereby indirectly retain control...

Adolescent and parent motivation for change affects psychotherapy outcomes among youth with poorly controlled diabetes.

PubMed

Ellis, Deborah A; Berio, Heidi; Carcone, April Idalski; Naar-King, Sylvie

2012-01-01

Investigate effect of baseline motivation for change on treatment fidelity, therapeutic alliance, treatment dose, and treatment outcome in a randomized controlled trial of family therapy for youth with poorly controlled diabetes. Seventy-four adolescents and caregivers completed measures of motivation for change. Measures of fidelity, alliance, dose, and youth health status were collected. Structural equation modeling was used to test the direct and indirect effects of motivation on treatment outcomes. Parent motivation was significantly related to alliance and fidelity. Only alliance was significantly related to posttreatment metabolic control. In adolescent models, only motivation was significantly related to alliance. In both models, motivation had a significant indirect effect on metabolic control through alliance. Findings demonstrate the importance of parent and youth initial motivational status and treatment alliance to treatment outcome among youth with poorly controlled diabetes. Additional research on treatment techniques that promote motivation for change is needed.

Spatially Compact Neural Clusters in the Dorsal Striatum Encode Locomotion Relevant Information.

PubMed

Barbera, Giovanni; Liang, Bo; Zhang, Lifeng; Gerfen, Charles R; Culurciello, Eugenio; Chen, Rong; Li, Yun; Lin, Da-Ting

2016-10-05

An influential striatal model postulates that neural activities in the striatal direct and indirect pathways promote and inhibit movement, respectively. Normal behavior requires coordinated activity in the direct pathway to facilitate intended locomotion and indirect pathway to inhibit unwanted locomotion. In this striatal model, neuronal population activity is assumed to encode locomotion relevant information. Here, we propose a novel encoding mechanism for the dorsal striatum. We identified spatially compact neural clusters in both the direct and indirect pathways. Detailed characterization revealed similar cluster organization between the direct and indirect pathways, and cluster activities from both pathways were correlated with mouse locomotion velocities. Using machine-learning algorithms, cluster activities could be used to decode locomotion relevant behavioral states and locomotion velocity. We propose that neural clusters in the dorsal striatum encode locomotion relevant information and that coordinated activities of direct and indirect pathway neural clusters are required for normal striatal controlled behavior. VIDEO ABSTRACT. Published by Elsevier Inc.

Optical micromanipulation of active cells with minimal perturbations: direct and indirect pushing.

PubMed

Wang, Chenlu; Chowdhury, Sagar; Gupta, Satyandra K; Losert, Wolfgang

2013-04-01

The challenge to wide application of optical tweezers in biological micromanipulation is the photodamage caused by high-intensity laser exposure to the manipulated living systems. While direct exposure to infrared lasers is less likely to kill cells, it can affect cell behavior and signaling. Pushing cells with optically trapped objects has been introduced as a less invasive alternative, but the technique includes some exposure of the biological object to parts of the optical tweezer beam. To keep the cells farther away from the laser, we introduce an indirect pushing-based technique for noninvasive manipulation of sensitive cells. We compare how cells respond to three manipulation approaches: direct manipulation, pushing, and indirect pushing. We find that indirect manipulation techniques lessen the impact of manipulation on cell behavior. Cell survival increases, as does the ability of cells to maintain shape and wiggle. Our experiments also demonstrate that indirect pushing allows cell-cell contacts to be formed in a controllable way, while retaining the ability of cells to change shape and move.

Direct and indirect responses of a freshwater food web to a potent synthetic oestrogen

PubMed Central

Kidd, Karen A.; Paterson, Michael J.; Rennie, Michael D.; Podemski, Cheryl L.; Findlay, Dave L.; Blanchfield, Paul J.; Liber, Karsten

2014-01-01

Endocrine-disrupting chemicals (EDCs) in municipal effluents directly affect the sexual development and reproductive success of fishes, but indirect effects on invertebrate prey or fish predators through reduced predation or prey availability, respectively, are unknown. At the Experimental Lakes Area in northwestern Ontario, Canada, a long-term, whole-lake experiment was conducted using a before-after-control-impact design to determine both direct and indirect effects of the synthetic oestrogen used in the birth control pill, 17α-ethynyloestradiol (EE2). Algal, microbial, zooplankton and benthic invertebrate communities showed no declines in abundance during three summers of EE2 additions (5–6 ng l−1), indicating no direct toxic effects. Recruitment of fathead minnow (Pimephales promelas) failed, leading to a near-extirpation of this species both 2 years during (young-of-year, YOY) and 2 years following (adults and YOY) EE2 additions. Body condition of male lake trout (Salvelinus namaycush) and male and female white sucker (Catostomus commersonii) declined before changes in prey abundance, suggesting direct effects of EE2 on this endpoint. Evidence of indirect effects of EE2 was also observed. Increases in zooplankton, Chaoborus, and emerging insects were observed after 2 or 3 years of EE2 additions, strongly suggesting indirect effects mediated through the reduced abundance of several small-bodied fishes. Biomass of top predator lake trout declined by 23–42% during and after EE2 additions, most probably an indirect effect from the loss of its prey species, the fathead minnow and slimy sculpin (Cottus cognatus). Our results demonstrate that small-scale studies focusing solely on direct effects are likely to underestimate the true environmental impacts of oestrogens in municipal wastewaters and provide further evidence of the value of whole-ecosystem experiments for understanding indirect effects of EDCs and other aquatic stressors. PMID:25405967