Reactive power and voltage control strategy based on dynamic and adaptive segment for DG inverter

NASA Astrophysics Data System (ADS)

Zhai, Jianwei; Lin, Xiaoming; Zhang, Yongjun

2018-03-01

The inverter of distributed generation (DG) can support reactive power to help solve the problem of out-of-limit voltage in active distribution network (ADN). Therefore, a reactive voltage control strategy based on dynamic and adaptive segment for DG inverter is put forward to actively control voltage in this paper. The proposed strategy adjusts the segmented voltage threshold of Q(U) droop curve dynamically and adaptively according to the voltage of grid-connected point and the power direction of adjacent downstream line. And then the reactive power reference of DG inverter can be got through modified Q(U) control strategy. The reactive power of inverter is controlled to trace the reference value. The proposed control strategy can not only control the local voltage of grid-connected point but also help to maintain voltage within qualified range considering the terminal voltage of distribution feeder and the reactive support for adjacent downstream DG. The scheme using the proposed strategy is compared with the scheme without the reactive support of DG inverter and the scheme using the Q(U) control strategy with constant segmented voltage threshold. The simulation results suggest that the proposed method has a significant improvement on solving the problem of out-of-limit voltage, restraining voltage variation and improving voltage quality.

Strategy to combat obesity and to promote physical activity in Arab countries.

PubMed

Musaiger, Abdulrahman O; Al Hazzaa, Hazzaa M; Al-Qahtani, Aayed; Elati, Jalila; Ramadan, Jasem; Aboulella, Nebal A; Mokhtar, Najat; Kilani, Hashem A

2011-01-01

Obesity has become a major public health problem in the Arab countries, creating a health and economic burden on these countries' government services. There is an urgent need to develop a strategy for prevention and control of obesity. The third Arab Conference on Obesity and Physical Activity was held in Bahrain in January 2010, and proposed the Strategy to Combat Obesity and Promote Physical Activity in Arab Countries. This strategy provides useful guidelines for each Arab country to prepare its own strategy or plan of action to prevent and control obesity. The strategy focused on expected outcomes, objectives, indicators to measure the objectives, and action needs for 9 target areas: child-care centers for preschool children, schools, primary health care, secondary care, food companies, food preparation institutes, media, public benefit organizations, and the workplace. Follow-up and future developments of this strategy were also included.

Strategy to combat obesity and to promote physical activity in Arab countries

PubMed Central

Musaiger, Abdulrahman O; Al Hazzaa, Hazzaa M; Al-Qahtani, Aayed; Elati, Jalila; Ramadan, Jasem; AboulElla, Nebal A; Mokhtar, Najat; Kilani, Hashem A

2011-01-01

Obesity has become a major public health problem in the Arab countries, creating a health and economic burden on these countries’ government services. There is an urgent need to develop a strategy for prevention and control of obesity. The third Arab Conference on Obesity and Physical Activity was held in Bahrain in January 2010, and proposed the Strategy to Combat Obesity and Promote Physical Activity in Arab Countries. This strategy provides useful guidelines for each Arab country to prepare its own strategy or plan of action to prevent and control obesity. The strategy focused on expected outcomes, objectives, indicators to measure the objectives, and action needs for 9 target areas: child-care centers for preschool children, schools, primary health care, secondary care, food companies, food preparation institutes, media, public benefit organizations, and the workplace. Follow-up and future developments of this strategy were also included. PMID:21660292

Controlling Contagion Processes in Activity Driven Networks

NASA Astrophysics Data System (ADS)

Liu, Suyu; Perra, Nicola; Karsai, Márton; Vespignani, Alessandro

2014-03-01

The vast majority of strategies aimed at controlling contagion processes on networks consider the connectivity pattern of the system either quenched or annealed. However, in the real world, many networks are highly dynamical and evolve, in time, concurrently with the contagion process. Here, we derive an analytical framework for the study of control strategies specifically devised for a class of time-varying networks, namely activity-driven networks. We develop a block variable mean-field approach that allows the derivation of the equations describing the coevolution of the contagion process and the network dynamic. We derive the critical immunization threshold and assess the effectiveness of three different control strategies. Finally, we validate the theoretical picture by simulating numerically the spreading process and control strategies in both synthetic networks and a large-scale, real-world, mobile telephone call data set.

Analysis of Active Figure Control Effects on Mounting Strategy for X-Ray Optics

NASA Technical Reports Server (NTRS)

Kolodziejczak, Jeffrey J.; Roche, Jacqueline M.; O'Dell, Stephen L.; Ramsey, Brian D.; Elsner, Ryan F.; Gubarev, Mikhail V.; Weisskopf, Martin C.

2014-01-01

As part of ongoing development efforts at MSFC, we have begun to investigate mounting strategies for highly nested x-ray optics in both full-shell and segmented configurations. The analytical infrastructure for this effort also lends itself to investigation of active strategies. We expect that a consequence of active figure control on relatively thin substrates is that errors are propagated to the edges, where they might affect the effective precision of the mounting points. Based upon modeling, we describe parametrically, the conditions under which active mounts are preferred over fixed ones, and the effect of active figure corrections on the required number, locations, and kinematic characteristics of mounting points.

Nutrition and Physical Activity Strategies for Cancer Prevention in Current National Comprehensive Cancer Control Program Plans

PubMed Central

Puckett, Mary; Neri, Antonio; Underwood, J. Michael; Stewart, Sherri L.

2016-01-01

Obesity, diet and physical inactivity are risk factors for some cancers. Grantees of the National Comprehensive Cancer Control Program (NCCCP) in US states, tribes, and territories develop plans to coordinate funding and activities for cancer prevention and control. Including information and goals related to nutrition and physical activity (NPA) is a key opportunity for primary cancer prevention, but it is currently unclear to what extent NCCCP plans address these issues. We reviewed 69 NCCCP plans and searched for terms related to NPA. Plans were coded as (1) knowledge of NPA and cancer link; (2) goals to improve NPA behaviors; and (3) strategies to increase healthy NPA activities, environments, or systems changes. NPA content was consistently included in all cancer plans examined across all years. Only 4 (6 %) outlined only the relationship between NPA and cancer without goals or strategies. Fifty-nine plans (89 %) contained goals or strategies related to NPA, with 53 (82 %) including both. However, numbers of goals, strategies, and detail provided varied widely. All programs recognized the importance of NPA in cancer prevention. Most plans included NPA goals and strategies. Increasing the presence of NPA strategies that can be modified or adapted appropriately locally could help with more widespread implementation and measurement of NPA interventions. PMID:26994988

The active control strategy on the output power for photovoltaic-storage systems based on extended PQ-QV-PV Node

NASA Astrophysics Data System (ADS)

Xu, Chen; Zhou, Bao-Rong; Zhai, Jian-Wei; Zhang, Yong-Jun; Yi, Ying-Qi

2017-05-01

In order to solve the problem of voltage exceeding specified limits and improve the penetration of photovoltaic in distribution network, we can make full use of the active power regulation ability of energy storage(ES) and the reactive power regulation ability of grid-connected photovoltaic inverter to provide support of active power and reactive power for distribution network. A strategy of actively controlling the output power for photovoltaic-storage system based on extended PQ-QV-PV node by analyzing the voltage regulating mechanism of point of commom coupling(PCC) of photovoltaic with energy storage(PVES) by controlling photovoltaic inverter and energy storage. The strategy set a small wave range of voltage to every photovoltaic by making the type of PCC convert among PQ, PV and QV. The simulation results indicate that the active control method can provide a better solution to the problem of voltage exceeding specified limits when photovoltaic is connectted to electric distribution network.

Effectiveness of a passive-active vibration isolation system with actuator constraints

NASA Astrophysics Data System (ADS)

Sun, Lingling; Sun, Wei; Song, Kongjie; Hansen, Colin H.

2014-05-01

In the prediction of active vibration isolation performance, control force requirements were ignored in previous work. This may limit the realization of theoretically predicted isolation performance if control force of large magnitude cannot be supplied by actuators. The behavior of a feed-forward active isolation system subjected to actuator output constraints is investigated. Distributed parameter models are developed to analyze the system response, and to produce a transfer matrix for the design of an integrated passive-active isolation system. Cost functions comprising a combination of the vibration transmission energy and the sum of the squared control forces are proposed. The example system considered is a rigid body connected to a simply supported plate via two passive-active isolation mounts. Vertical and transverse forces as well as a rotational moment are applied at the rigid body, and resonances excited in elastic mounts and the supporting plate are analyzed. The overall isolation performance is evaluated by numerical simulation. The simulation results are then compared with those obtained using unconstrained control strategies. In addition, the effects of waves in elastic mounts are analyzed. It is shown that the control strategies which rely on unconstrained actuator outputs may give substantial power transmission reductions over a wide frequency range, but also require large control force amplitudes to control excited vibration modes of the system. Expected power transmission reductions for modified control strategies that incorporate constrained actuator outputs are considerably less than typical reductions with unconstrained actuator outputs. In the frequency range in which rigid body modes are present, the control strategies can only achieve 5-10 dB power transmission reduction, when control forces are constrained to be the same order of the magnitude as the primary vertical force. The resonances of the elastic mounts result in a notable increase of power transmission in high frequency range and cannot be attenuated by active control. The investigation provides a guideline for design and evaluation of active vibration isolation systems.

A multiobjective ? control strategy for energy harvesting in regenerative vehicle suspension systems

NASA Astrophysics Data System (ADS)

Casavola, Alessandro; Di Iorio, Fabio; Tedesco, Francesco

2018-04-01

A significant amount of energy induced by road unevenness and vehicle roll and pitch motions is usually dissipated by conventional shock-absorbers. In this paper, a novel active multiobjective ? control design methodology is proposed which explicitly includes, besides the usual control objectives on ride comfort, road handling and suspension stroke, the amount of energy to be harvested as an additional, though conflicting, control objective and allows the designer to directly trade-off among them depending on the application. An electromechanical regenerative suspension system is considered where the viscous damper is replaced by a linear electrical motor which is actively governed. It is shown that the proposed control law is able to achieve remarkable improvements on the amount of the harvested energy with respect to passive or semi-active control strategies while maintaining the other objectives at acceptable levels. Simulative studies undertaken via CarSim are also reported that confirm the potentiality and flexibility of the proposed control design strategy.

Multi-objective decoupling algorithm for active distance control of intelligent hybrid electric vehicle

NASA Astrophysics Data System (ADS)

Luo, Yugong; Chen, Tao; Li, Keqiang

2015-12-01

The paper presents a novel active distance control strategy for intelligent hybrid electric vehicles (IHEV) with the purpose of guaranteeing an optimal performance in view of the driving functions, optimum safety, fuel economy and ride comfort. Considering the complexity of driving situations, the objects of safety and ride comfort are decoupled from that of fuel economy, and a hierarchical control architecture is adopted to improve the real-time performance and the adaptability. The hierarchical control structure consists of four layers: active distance control object determination, comprehensive driving and braking torque calculation, comprehensive torque distribution and torque coordination. The safety distance control and the emergency stop algorithms are designed to achieve the safety and ride comfort goals. The optimal rule-based energy management algorithm of the hybrid electric system is developed to improve the fuel economy. The torque coordination control strategy is proposed to regulate engine torque, motor torque and hydraulic braking torque to improve the ride comfort. This strategy is verified by simulation and experiment using a forward simulation platform and a prototype vehicle. The results show that the novel control strategy can achieve the integrated and coordinated control of its multiple subsystems, which guarantees top performance of the driving functions and optimum safety, fuel economy and ride comfort.

Neuromuscular strategies for lumbopelvic control during frontal and sagittal plane movement challenges differ between people with and without low back pain.

PubMed

Nelson-Wong, E; Poupore, K; Ingvalson, S; Dehmer, K; Piatte, A; Alexander, S; Gallant, P; McClenahan, B; Davis, A M

2013-12-01

Observation-based assessments of movement are a standard component in clinical assessment of patients with non-specific low back pain. While aberrant motion patterns can be detected visually, clinicians are unable to assess underlying neuromuscular strategies during these tests. The purpose of this study was to compare coordination of the trunk and hip muscles during 2 commonly used assessments for lumbopelvic control in people with low back pain (LBP) and matched control subjects. Electromyography was recorded from hip and trunk muscles of 34 participants (17 with LBP) during performance of the Active Hip Abduction (AHAbd) and Active Straight Leg Raise (ASLR) tests. Relative muscle timing was calculated using cross-correlation. Participants with LBP demonstrated a variable strategy, while control subjects used a consistent proximal to distal activation strategy during both frontal and sagittal plane movements. Findings from this study provide insight into underlying neuromuscular control during commonly used assessment tests for patients with LBP that may help to guide targeted intervention approaches. Copyright © 2013 Elsevier Ltd. All rights reserved.

A randomised controlled trial of an active telephone-based recruitment strategy to increase childcare-service staff attendance at a physical activity and nutrition training workshop.

PubMed

Yoong, Sze Lin; Wolfenden, Luke; Finch, Meghan; Williams, Amanda; Dodds, Pennie; Gillham, Karen; Wyse, Rebecca

2013-12-01

Centre-based childcare services represent a promising setting to target the prevention of excessive weight gain in preschool-aged children. Staff training is a key component of multi-strategy interventions to improve implementation of effective physical activity and nutrition promoting practices for obesity prevention in childcare services. This randomised controlled trial aimed to examine whether an active telephone-based strategy to invite childcare-service staff to attend a training workshop was effective in increasing the proportion of services with staff attending training, compared with a passive strategy. Services were randomised to an active telephone-based or a passive-recruitment strategy. Those in the active arm received an email invitation and one to three follow-up phone calls, whereas services in the passive arm were informed of the availability of training only via newsletters. The proportion of services with staff attending the training workshop was compared between the two arms. One hundred and twenty-eight services were included in this study. A significantly larger proportion (52%) of services in the active arm compared with those in the passive-strategy arm (3.1%) attended training (d.f.=1, χ2=34.3; P<0.001). An active, telephone-based recruitment strategy significantly increased the proportion of childcare services with staff attending training. Further strategies to improve staff attendance at training need to be identified and implemented. SO WHAT?: Active-recruitment strategies including follow-up telephone calls should be utilised to invite staff to participate in training, in order to maximise the use of training as an implementation strategy for obesity prevention in childcare services.

Nonlinear analysis of switched semi-active controlled systems

NASA Astrophysics Data System (ADS)

Eslaminasab, Nima; Vahid A., Orang; Golnaraghi, Farid

2011-02-01

Semi-active systems improve suspension performance of the vehicles more effectively than conventional passive systems by simultaneously improving ride comfort and road handling. Also, because of size, weight, price and performance advantages, they have gained more interest over the active as well as passive systems. Probably the most neglected aspect of the semi-active on-off control systems and strategies is the effects of the added nonlinearities of those systems, which are introduced and analysed in this paper. To do so, numerical techniques, analytical method of averaging and experimental analysis are deployed. In this paper, a new method to analyse, calculate and compare the performances of the semi-active controlled systems is proposed; further, a new controller based on the observations of actual test data is proposed to eliminate the adverse effects of added nonlinearities. The significance of the proposed new system is the simplicity of the algorithm and ease of implementation. In fact, this new semi-active control strategy could be easily adopted and used with most of the existing semi-active control systems.

Weight-control behaviors and subsequent weight change among adolescents and young adult females123

PubMed Central

Haines, Jess; Rosner, Bernard; Willett, Walter C

2010-01-01

Background: Little is known about the effectiveness of behavioral strategies to prevent long-term weight gain among adolescents and young adults. Objective: The objective was to assess the relation of dietary and physical activity weight-control strategies, alone and together, with subsequent weight change. Design: This was a prospective study of 4456 female adolescents and young adults aged 14–22 y in the ongoing Growing Up Today Study. Weight-control behaviors, including dietary approaches and physical activity, were self-reported in 2001 and were used to predict weight change from 2001 to 2005. Results: In 2001–2002, 23.7% of female adolescents and young adults were trying to maintain their weight and another 54.4% were trying to lose weight. Approximately 25% used each of the following weight-control strategies: not eating snacks, following low-calorie or low-fat diets, and limiting portion sizes. In addition, 47.7% reported exercising at least occasionally for weight control. During 4 y of follow-up, participants gained an average of 3.3 kg. None of the dietary approaches to weight control predicted less weight change; however, females who exercised ≥5 d/wk gained significantly less weight than did their peers (−0.9 kg; 95% CI: −1.4, −0.4). The most successful strategy for weight-gain prevention among the females was to limit portion sizes (−1.9 kg; 95% CI: −2.6, −1.1) combined with frequent exercise. Conclusions: Our results suggest that physical activity is a necessary strategy for long-term weight control among adolescents and young adult females. Combining dietary weight-control approaches with physical activity is the most effective method for reducing weight gain. PMID:19889827

The Preventive Control of Zoonotic Visceral Leishmaniasis: Efficacy and Economic Evaluation

PubMed Central

Wu, Jianhong; Massad, Eduardo

2017-01-01

Zoonotic Visceral Leishmaniasis (ZVL) is one of the world's deadliest and neglected infectious diseases, according to World Health Organization. This disease is one of major human and veterinary medical significance. The sandfly and the reservoir in urban areas remain among the major challenges for the control activities. In this paper, we evaluated five control strategies (positive dog elimination, insecticide impregnated dog collar, dog vaccination, dog treatment, and sandfly population control), considering disease control results and cost-effectiveness. We elaborated a mathematical model based on a set of differential equations in which three populations were represented (human, dog, and sandfly). Humans and dogs were divided into susceptible, latent, clinically ill, and recovery categories. Sandflies were divided into noninfected, infected, and infective. As the main conclusions, the insecticide impregnated dog collar was the strategy that presented the best combination between disease control and cost-effectiveness. But, depending on the population target, the control results and cost-effectiveness of each strategy may differ. More and detailed studies are needed, specially one which optimizes the control considering more than one strategy in activity. PMID:28588642

The Preventive Control of Zoonotic Visceral Leishmaniasis: Efficacy and Economic Evaluation.

PubMed

Shimozako, Helio Junji; Wu, Jianhong; Massad, Eduardo

2017-01-01

Zoonotic Visceral Leishmaniasis (ZVL) is one of the world's deadliest and neglected infectious diseases, according to World Health Organization. This disease is one of major human and veterinary medical significance. The sandfly and the reservoir in urban areas remain among the major challenges for the control activities. In this paper, we evaluated five control strategies (positive dog elimination, insecticide impregnated dog collar, dog vaccination, dog treatment, and sandfly population control), considering disease control results and cost-effectiveness. We elaborated a mathematical model based on a set of differential equations in which three populations were represented (human, dog, and sandfly). Humans and dogs were divided into susceptible, latent, clinically ill, and recovery categories. Sandflies were divided into noninfected, infected, and infective. As the main conclusions, the insecticide impregnated dog collar was the strategy that presented the best combination between disease control and cost-effectiveness. But, depending on the population target, the control results and cost-effectiveness of each strategy may differ. More and detailed studies are needed, specially one which optimizes the control considering more than one strategy in activity.

Optimized active traffic management and speed harmonization in work zones.

DOT National Transportation Integrated Search

2014-01-01

Traffic and demand management are major strategies to control delay and congestion in : highway bottlenecks including work zones. The Federal Highway Administration (FHWA) : introduced innovative strategies, called Active Traffic and Demand Managemen...

Asthma in pregnancy: management strategies.

PubMed

McCallister, Jennifer W

2013-01-01

Asthma is one of the most prevalent chronic medical conditions to complicate pregnancy. With approximately one-third of women experiencing a worsening of control during the course of their pregnancy, identifying those at greatest risk has the potential to improve maternal and fetal outcomes for a large number of pregnancies. Similarly, active management strategies that prioritize asthma control in this vulnerable population can have a far-reaching impact. Demographic characteristics and patient noncompliance place certain populations of pregnant women at increased risk of poor asthma control during pregnancy. In addition, undertreatment and disparities in care of acute exacerbations during pregnancy likely contribute. Targeted educational interventions and treatment algorithms using objective markers of disease activity have shown improved outcomes in asthma control. Active management strategies which focus on identifying patient-specific risk factors, patient and provider education, and targeted treatment interventions can improve asthma care for women during pregnancy.

Human-like Compliance for Dexterous Robot Hands

NASA Technical Reports Server (NTRS)

Jau, Bruno M.

1995-01-01

This paper describes the Active Electromechanical Compliance (AEC) system that was developed for the Jau-JPL anthropomorphic robot. The AEC system imitates the functionality of the human muscle's secondary function, which is to control the joint's stiffness: AEC is implemented through servo controlling the joint drive train's stiffness. The control strategy, controlling compliant joints in teleoperation, is described. It enables automatic hybrid position and force control through utilizing sensory feedback from joint and compliance sensors. This compliant control strategy is adaptable for autonomous robot control as well. Active compliance enables dual arm manipulations, human-like soft grasping by the robot hand, and opens the way to many new robotics applications.

Controlling the self-organizing dynamics in a sandpile model on complex networks by failure tolerance

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

Qi, Junjian; Pfenninger, Stefan

In this paper, we propose a strategy to control the self-organizing dynamics of the Bak-Tang-Wiesenfeld (BTW) sandpile model on complex networks by allowing some degree of failure tolerance for the nodes and introducing additional active dissipation while taking the risk of possible node damage. We show that the probability for large cascades significantly increases or decreases respectively when the risk for node damage outweighs the active dissipation and when the active dissipation outweighs the risk for node damage. By considering the potential additional risk from node damage, a non-trivial optimal active dissipation control strategy which minimizes the total cost inmore » the system can be obtained. Under some conditions the introduced control strategy can decrease the total cost in the system compared to the uncontrolled model. Moreover, when the probability of damaging a node experiencing failure tolerance is greater than the critical value, then no matter how successful the active dissipation control is, the total cost of the system will have to increase. This critical damage probability can be used as an indicator of the robustness of a network or system. Copyright (C) EPLA, 2015« less

Effects of Activity Based Blended Learning Strategy on Prospective of Teachers' Achievement and Motivation

ERIC Educational Resources Information Center

Abdelraheem, Ahmed Yousif; Ahmed, Abdelrahman Mohammed

2015-01-01

The study investigates the effect of Activity based Blended Learning strategy and Conventional Blended Learning strategy on students' achievement and motivation. Two groups namely, experimental and control group from Sultan Qaboos University were selected randomly for the study. To assess students' achievement in the different groups, pre- and…

Ventral striatum and the evaluation of memory retrieval strategies.

PubMed

Badre, David; Lebrecht, Sophie; Pagliaccio, David; Long, Nicole M; Scimeca, Jason M

2014-09-01

Adaptive memory retrieval requires mechanisms of cognitive control that facilitate the recovery of goal-relevant information. Frontoparietal systems are known to support control of memory retrieval. However, the mechanisms by which the brain acquires, evaluates, and adapts retrieval strategies remain unknown. Here, we provide evidence that ventral striatal activation tracks the success of a retrieval strategy and correlates with subsequent reliance on that strategy. Human participants were scanned with fMRI while performing a lexical decision task. A rule was provided that indicated the likely semantic category of a target word given the category of a preceding prime. Reliance on the rule improved decision-making, as estimated within a drift diffusion framework. Ventral striatal activation tracked the benefit that relying on the rule had on decision-making. Moreover, activation in ventral striatum correlated with a participant's subsequent reliance on the rule. Taken together, these results support a role for ventral striatum in learning and evaluating declarative retrieval strategies.

[Physiotherapy for juvenile idiopathic arthritis].

PubMed

Spamer, M; Georgi, M; Häfner, R; Händel, H; König, M; Haas, J-P

2012-07-01

Control of disease activity and recovery of function are major issues in the treatment of children and adolescents suffering from juvenile idiopathic arthritis (JIA). Functional therapies including physiotherapy are important components in the multidisciplinary teamwork and each phase of the disease requires different strategies. While in the active phase of the disease pain alleviation is the main focus, the inactive phase requires strategies for improving motility and function. During remission the aim is to regain general fitness by sports activities. These phase adapted strategies must be individually designed and usually require a combination of different measures including physiotherapy, occupational therapy, massage as well as other physical procedures and sport therapy. There are only few controlled studies investigating the effectiveness of physical therapies in JIA and many strategies are derived from long-standing experience. New results from physiology and sport sciences have contributed to the development in recent years. This report summarizes the basics and main strategies of physical therapy in JIA.

Management strategy evaluation of pheromone-baited trapping techniques to improve management of invasive sea lamprey

USGS Publications Warehouse

Dawson, Heather; Jones, Michael L.; Irwin, Brian J.; Johnson, Nicholas; Wagner, Michael C.; Szymanski, Melissa

2016-01-01

We applied a management strategy evaluation (MSE) model to examine the potential cost-effectiveness of using pheromone-baited trapping along with conventional lampricide treatment to manage invasive sea lamprey. Four pheromone-baited trapping strategies were modeled: (1) stream activation wherein pheromone was applied to existing traps to achieve 10−12 mol/L in-stream concentration, (2) stream activation plus two additional traps downstream with pheromone applied at 2.5 mg/hr (reverse-intercept approach), (3) trap activation wherein pheromone was applied at 10 mg/hr to existing traps, and (4) trap activation and reverse-intercept approach. Each new strategy was applied, with remaining funds applied to conventional lampricide control. Simulating deployment of these hybrid strategies on fourteen Lake Michigan streams resulted in increases of 17 and 11% (strategies 1 and 2) and decreases of 4 and 7% (strategies 3 and 4) of the lakewide mean abundance of adult sea lamprey relative to status quo. MSE revealed performance targets for trap efficacy to guide additional research because results indicate that combining lampricides and high efficacy trapping technologies can reduce sea lamprey abundance on average without increasing control costs.

Feasibility of Pairing Behavioral Activation With Exercise for Women With Type 2 Diabetes and Depression: The Get It Study Pilot Randomized Controlled Trial

PubMed Central

Schneider, Kristin L.; Panza, Emily; Handschin, Barbara; Ma, Yunsheng; Busch, Andrew M.; Waring, Molly E.; Appelhans, Bradley M.; Whited, Matthew C.; Keeney, Jacey; Kern, Daniel; Blendea, Mihaela; Ockene, Ira; Pagoto, Sherry L.

2016-01-01

Major depressive disorder is often comorbid with diabetes and associated with worse glycemic control. Exercise improves glycemic control and depression, and thus could be a parsimonious intervention for patients with comorbid diabetes and major depression. Because patients with diabetes and comorbid depression are often sedentary and lack motivation to exercise, we developed a group exercise intervention that integrates strategies from behavioral activation therapy for depression to increase motivation for and enjoyment of exercise. We conducted a 6-month pilot randomized controlled trial to test the feasibility of the behavioral activation exercise intervention (EX) for women with diabetes and depression. Of the 715 individuals who contacted us about the study, 29 participants were randomized to the EX condition or an enhanced usual care condition (EUC), which represents 4.1% of participants who initially contacted us. Inclusion criteria made recruitment challenging and limits the feasibility of recruiting women with diabetes and depression for a larger trial of the intervention. Retention was 96.5% and 86.2% at 3 and 6 months. Participants reported high treatment acceptability; use of behavioral activation strategies and exercise class attendance was acceptable. No condition differences were observed for glycemic control, depressive symptoms, and physical activity, though depressive symptoms and self-reported physical activity improved over time. Compared to participants in the EUC condition, participants in the EX condition reported greater exercise enjoyment and no increase in avoidance behavior over time. Using behavioral activation strategies to increase exercise is feasible in a group exercise setting. However, whether these strategies can be delivered in a less intensive manner to a broader population of sedentary adults, for greater initiation and maintenance of physical activity, deserves further study. PMID:26956652

Feasibility of Pairing Behavioral Activation With Exercise for Women With Type 2 Diabetes and Depression: The Get It Study Pilot Randomized Controlled Trial.

PubMed

Schneider, Kristin L; Panza, Emily; Handschin, Barbara; Ma, Yunsheng; Busch, Andrew M; Waring, Molly E; Appelhans, Bradley M; Whited, Matthew C; Keeney, Jacey; Kern, Daniel; Blendea, Mihaela; Ockene, Ira; Pagoto, Sherry L

2016-03-01

Major depressive disorder is often comorbid with diabetes and associated with worse glycemic control. Exercise improves glycemic control and depression, and thus could be a parsimonious intervention for patients with comorbid diabetes and major depression. Because patients with diabetes and comorbid depression are often sedentary and lack motivation to exercise, we developed a group exercise intervention that integrates strategies from behavioral activation therapy for depression to increase motivation for and enjoyment of exercise. We conducted a 6-month pilot randomized controlled trial to test the feasibility of the behavioral activation exercise intervention (EX) for women with diabetes and depression. Of the 715 individuals who contacted us about the study, 29 participants were randomized to the EX condition or an enhanced usual care condition (EUC), which represents 4.1% of participants who initially contacted us. Inclusion criteria made recruitment challenging and limits the feasibility of recruiting women with diabetes and depression for a larger trial of the intervention. Retention was 96.5% and 86.2% at 3 and 6months. Participants reported high treatment acceptability; use of behavioral activation strategies and exercise class attendance was acceptable. No condition differences were observed for glycemic control, depressive symptoms, and physical activity, though depressive symptoms and self-reported physical activity improved over time. Compared to participants in the EUC condition, participants in the EX condition reported greater exercise enjoyment and no increase in avoidance behavior over time. Using behavioral activation strategies to increase exercise is feasible in a group exercise setting. However, whether these strategies can be delivered in a less intensive manner to a broader population of sedentary adults, for greater initiation and maintenance of physical activity, deserves further study. Copyright © 2015. Published by Elsevier Ltd.

Intelligent vehicle safety control strategy in various driving situations

NASA Astrophysics Data System (ADS)

Moon, Seungwuk; Cho, Wanki; Yi, Kyongsu

2010-12-01

This paper describes a safety control strategy for intelligent vehicles with the objective of optimally coordinating the throttle, brake, and active front steering actuator inputs to obtain both lateral stability and longitudinal safety. The control system consists of a supervisor, control algorithms, and a coordinator. From the measurement and estimation signals, the supervisor determines the active control modes among normal driving, longitudinal safety, lateral stability, and integrated safety control mode. The control algorithms consist of longitudinal and lateral stability controllers. The longitudinal controller is designed to improve the driver's comfort during normal, safe-driving situations, and to avoid rear-end collision in vehicle-following situations. The lateral stability controller is designed to obtain the required manoeuvrability and to limit the vehicle body's side-slip angle. To obtain both longitudinal safety and lateral stability control in various driving situations, the coordinator optimally determines the throttle, brake, and active front steering inputs based on the current status of the subject vehicle. Closed-loop simulations with the driver-vehicle-controller system are conducted to investigate the performance of the proposed control strategy. From these simulation results, it is shown that the proposed control algorithm assists the driver in combined severe braking/large steering manoeuvring so that the driver can maintain good manoeuvrability and prevent the vehicle from crashing in vehicle-following situations.

Performance and robustness of hybrid model predictive control for controllable dampers in building models

NASA Astrophysics Data System (ADS)

Johnson, Erik A.; Elhaddad, Wael M.; Wojtkiewicz, Steven F.

2016-04-01

A variety of strategies have been developed over the past few decades to determine controllable damping device forces to mitigate the response of structures and mechanical systems to natural hazards and other excitations. These "smart" damping devices produce forces through passive means but have properties that can be controlled in real time, based on sensor measurements of response across the structure, to dramatically reduce structural motion by exploiting more than the local "information" that is available to purely passive devices. A common strategy is to design optimal damping forces using active control approaches and then try to reproduce those forces with the smart damper. However, these design forces, for some structures and performance objectives, may achieve high performance by selectively adding energy, which cannot be replicated by a controllable damping device, causing the smart damper performance to fall far short of what an active system would provide. The authors have recently demonstrated that a model predictive control strategy using hybrid system models, which utilize both continuous and binary states (the latter to capture the switching behavior between dissipative and non-dissipative forces), can provide reductions in structural response on the order of 50% relative to the conventional clipped-optimal design strategy. This paper explores the robustness of this newly proposed control strategy through evaluating controllable damper performance when the structure model differs from the nominal one used to design the damping strategy. Results from the application to a two-degree-of-freedom structure model confirms the robustness of the proposed strategy.

Foot placement control and gait instability among people with stroke

PubMed Central

Dean, Jesse C.; Kautz, Steven A.

2016-01-01

Gait instability is a common problem following stroke, as evidenced by increases in fall risk and fear of falling. However, the mechanism underlying gait instability is currently unclear. We recently found that young, healthy humans use a consistent gait stabilization strategy of actively controlling their mediolateral foot placement based on the concurrent mechanical state of the stance limb. In the present work, we tested whether people with stroke (n = 16) and age-matched controls (n = 19) used this neuromechanical strategy. Specifically, we used multiple linear regressions to test whether (1) swing phase gluteus medius (GM) activity was influenced by the simultaneous state of the stance limb and (2) mediolateral foot placement location was influenced by swing phase GM activity and the mechanical state of the swing limb at the start of the step. We found that both age-matched controls and people with stroke classified as having a low fall risk (Dynamic Gait Index [DGI] score >19) essentially used the stabilization strategy previously described in young controls. In contrast, this strategy was disrupted for people with stroke classified as higher fall risk (DGI

Instructional Design, Active Learning, and Student Performance: Using a Trading Room to Teach Strategy

ERIC Educational Resources Information Center

Stewart, Alice C.; Houghton, Susan M.; Rogers, Patrick R.

2012-01-01

This research used a quasi-experimental design with two conditions to test the impact of active learning in the context of integrated instructional design. The control condition was a traditional approach to teaching an undergraduate strategy capstone class. The intervention condition was an undergraduate strategy capstone class that was designed…

Do job demands and job control affect problem-solving?

PubMed

Bergman, Peter N; Ahlberg, Gunnel; Johansson, Gun; Stoetzer, Ulrich; Aborg, Carl; Hallsten, Lennart; Lundberg, Ingvar

2012-01-01

The Job Demand Control model presents combinations of working conditions that may facilitate learning, the active learning hypothesis, or have detrimental effects on health, the strain hypothesis. To test the active learning hypothesis, this study analysed the effects of job demands and job control on general problem-solving strategies. A population-based sample of 4,636 individuals (55% women, 45% men) with the same job characteristics measured at two times with a three year time lag was used. Main effects of demands, skill discretion, task authority and control, and the combined effects of demands and control were analysed in logistic regressions, on four outcomes representing general problem-solving strategies. Those reporting high on skill discretion, task authority and control, as well as those reporting high demand/high control and low demand/high control job characteristics were more likely to state using problem solving strategies. Results suggest that working conditions including high levels of control may affect how individuals cope with problems and that workplace characteristics may affect behaviour in the non-work domain.

Multi-criteria evaluation of wastewater treatment plant control strategies under uncertainty.

PubMed

Flores-Alsina, Xavier; Rodríguez-Roda, Ignasi; Sin, Gürkan; Gernaey, Krist V

2008-11-01

The evaluation of activated sludge control strategies in wastewater treatment plants (WWTP) via mathematical modelling is a complex activity because several objectives; e.g. economic, environmental, technical and legal; must be taken into account at the same time, i.e. the evaluation of the alternatives is a multi-criteria problem. Activated sludge models are not well characterized and some of the parameters can present uncertainty, e.g. the influent fractions arriving to the facility and the effect of either temperature or toxic compounds on the kinetic parameters, having a strong influence in the model predictions used during the evaluation of the alternatives and affecting the resulting rank of preferences. Using a simplified version of the IWA Benchmark Simulation Model No. 2 as a case study, this article shows the variations in the decision making when the uncertainty in activated sludge model (ASM) parameters is either included or not during the evaluation of WWTP control strategies. This paper comprises two main sections. Firstly, there is the evaluation of six WWTP control strategies using multi-criteria decision analysis setting the ASM parameters at their default value. In the following section, the uncertainty is introduced, i.e. input uncertainty, which is characterized by probability distribution functions based on the available process knowledge. Next, Monte Carlo simulations are run to propagate input through the model and affect the different outcomes. Thus (i) the variation in the overall degree of satisfaction of the control objectives for the generated WWTP control strategies is quantified, (ii) the contributions of environmental, legal, technical and economic objectives to the existing variance are identified and finally (iii) the influence of the relative importance of the control objectives during the selection of alternatives is analyzed. The results show that the control strategies with an external carbon source reduce the output uncertainty in the criteria used to quantify the degree of satisfaction of environmental, technical and legal objectives, but increasing the economical costs and their variability as a trade-off. Also, it is shown how a preliminary selected alternative with cascade ammonium controller becomes less desirable when input uncertainty is included, having simpler alternatives more chance of success.

The effect of active learning on student characteristics in a human physiology course for nonmajors.

PubMed

Wilke, R Russell

2003-12-01

This study investigated the effect of active-learning strategies on college students' achievement, motivation, and self-efficacy in a human physiology course for nonmajors. Variables were studied via a quasi-experimental, Solomon four-group design on 141 students at a small west-Texas university. Treatment groups were taught using a continuum-based, active-learning model implemented over the course of a semester. Control groups were taught using traditional didactic lecture methods. To assess the effects of the continuum-based active learning strategies, students were administered a comprehensive physiology content exam, the Motivated Strategies for Learning Questionnaire, and attitude surveys. Factorial analyses indicated that the treatment groups acquired significantly more content knowledge and were significantly more self-efficacious than students in the control groups. There were no significant differences in motivation. Attitude surveys indicated that students in both the treatment and control groups demonstrated a positive attitude toward active learning, believed it helped (or would help) them to learn the material, and would choose an active learning course in the future.

Task-specificity of bilateral anticipatory activation of the deep abdominal muscles in healthy and chronic low back pain populations.

PubMed

Massé-Alarie, Hugo; Beaulieu, Louis-David; Preuss, Richard; Schneider, Cyril

2015-02-01

Cross-sectional study of lumbopelvic muscle activation during rapid limb movements in chronic low back pain (CLBP) patients and healthy controls. Controversy exists over whether bilateral anticipatory activation of the deep abdominal muscles represents a normal motor control strategy prior to all rapid limb movements, or if this is simply a task-specific strategy appropriate for only certain movement conditions. To assess the onset timing of the transversus abdominis/internal oblique muscles (TrA/IO) during two rapid limb movement tasks with different postural demands - bilateral shoulder flexion in standing, unilateral hip extension in prone lying - as well as differences between CLBP and controls. Twelve CLBP and 13 controls performed the two tasks in response to an auditory cue. Surface EMG was acquired bilaterally from five muscles, including TrA/IO. In both groups, 50% of bilateral shoulder flexion trials showed bilateral anticipatory TrA/IO activation. This was rare, however, in unilateral hip extension for which only the TrA/IO contralateral to the moving leg showed anticipatory activation. The only significant difference in lumbo-pelvic muscle onset timing between CLBP and controls was a delay in semitendinosus activation during bilateral shoulder flexion in standing. Our data suggest that bilateral anticipatory TrA/IO activation is a task-specific motor control strategy, appropriate for only certain rapid limb movement conditions. Furthermore, the presence of altered semitendinosus onset timing in the CLBP group during bilateral shoulder flexion may be reflective of other possible lumbo-pelvic motor control alterations among this population. Copyright © 2014 Elsevier B.V. All rights reserved.

Age-related impairments in active learning and strategic visual exploration.

PubMed

Brandstatt, Kelly L; Voss, Joel L

2014-01-01

Old age could impair memory by disrupting learning strategies used by younger individuals. We tested this possibility by manipulating the ability to use visual-exploration strategies during learning. Subjects controlled visual exploration during active learning, thus permitting the use of strategies, whereas strategies were limited during passive learning via predetermined exploration patterns. Performance on tests of object recognition and object-location recall was matched for younger and older subjects for objects studied passively, when learning strategies were restricted. Active learning improved object recognition similarly for younger and older subjects. However, active learning improved object-location recall for younger subjects, but not older subjects. Exploration patterns were used to identify a learning strategy involving repeat viewing. Older subjects used this strategy less frequently and it provided less memory benefit compared to younger subjects. In previous experiments, we linked hippocampal-prefrontal co-activation to improvements in object-location recall from active learning and to the exploration strategy. Collectively, these findings suggest that age-related memory problems result partly from impaired strategies during learning, potentially due to reduced hippocampal-prefrontal co-engagement.

Evaluation of the performance of a passive-active vibration isolation system

NASA Astrophysics Data System (ADS)

Sun, L. L.; Hansen, C. H.; Doolan, C.

2015-01-01

The behavior of a feedforward active isolation system subjected to actuator output constraints is investigated. Distributed parameter models are developed to analyze the system response, and to produce a transfer matrix for the design of an integrated passive-active isolation system. Cost functions considered here comprise a combination of the vibration transmission energy and the sum of the squared control forces. The example system considered is a rigid body connected to a simply supported plate via two isolation mounts. The overall isolation performance is evaluated by numerical simulation. The results show that the control strategies which rely on unconstrained actuator outputs may give substantial power transmission reductions over a wide frequency range, but also require large control force amplitudes to control excited vibration modes of the system. Expected power transmission reductions for modified control strategies that incorporate constrained actuator outputs are considerably less than typical reductions with unconstrained actuator outputs. The active system with constrained control force outputs is shown to be more effective at the resonance frequencies of the supporting plate. However, in the frequency range in which rigid body modes are present, the control strategies employed using constrained actuator outputs can only achieve 5-10 dB power transmission reduction, while at off-resonance frequencies, little or no power transmission reduction can be obtained with realistic control forces. Analysis of the wave effects in the passive mounts is also presented.

The neural correlates of strategic reading comprehension: cognitive control and discourse comprehension.

PubMed

Moss, Jarrod; Schunn, Christian D; Schneider, Walter; McNamara, Danielle S; Vanlehn, Kurt

2011-09-15

Neuroimaging studies of text comprehension conducted thus far have shed little light on the brain mechanisms underlying strategic learning from text. Thus, the present study was designed to answer the question of what brain areas are active during performance of complex reading strategies. Reading comprehension strategies are designed to improve a reader's comprehension of a text. For example, self-explanation is a complex reading strategy that enhances existing comprehension processes. It was hypothesized that reading strategies would involve areas of the brain that are normally involved in reading comprehension along with areas that are involved in strategic control processes because the readers are intentionally using a complex reading strategy. Subjects were asked to reread, paraphrase, and self-explain three different texts in a block design fMRI study. Activation was found in both executive control and comprehension areas, and furthermore, learning from text was associated with activation in the anterior prefrontal cortex (aPFC). The authors speculate that the aPFC may play a role in coordinating the internal and external modes of thought that are necessary for integrating new knowledge from texts with prior knowledge. Copyright © 2011 Elsevier Inc. All rights reserved.

Prefrontal activity and impaired memory encoding strategies in schizophrenia.

PubMed

Guimond, Synthia; Hawco, Colin; Lepage, Martin

2017-08-01

Schizophrenia patients have significant memory difficulties that have far-reaching implications in their daily life. These impairments are partly attributed to an inability to self-initiate effective memory encoding strategies, but its core neurobiological correlates remain unknown. The current study addresses this critical gap in our knowledge of episodic memory impairments in schizophrenia. Schizophrenia patients (n = 35) and healthy controls (n = 23) underwent a Semantic Encoding Memory Task (SEMT) during an fMRI scan. Brain activity was examined for conditions where participants were a) prompted to use semantic encoding strategies, or b) not prompted but required to self-initiate such strategies. When prompted to use semantic encoding strategies, schizophrenia patients exhibited similar recognition performance and brain activity as healthy controls. However, when required to self-initiate these strategies, patients had significant reduced recognition performance and brain activity in the left dorsolateral prefrontal cortex, as well as in the left temporal gyrus, left superior parietal lobule, and cerebellum. When patients were divided based on performance on the SEMT, the subgroup with more severe deficits in self-initiation also showed greater reduction in left dorsolateral prefrontal activity. These results suggest that impaired self-initiation of elaborative encoding strategies is a driving feature of memory deficits in schizophrenia. We also identified the neural correlates of impaired self-initiation of semantic encoding strategies, in which a failure to activate the left dorsolateral prefrontal cortex plays a key role. These findings provide important new targets in the development of novel treatments aiming to improve memory and ultimately patients' outcome. Copyright © 2017. Published by Elsevier Ltd.

Gastrocnemius myoelectric control of a robotic hip exoskeleton.

PubMed

Grazi, Lorenzo; Crea, Simona; Parri, Andrea; Yan, Tingfang; Cortese, Mario; Giovacchini, Francesco; Cempini, Marco; Pasquini, Guido; Micera, Silvestro; Vitiello, Nicola

2015-01-01

In this paper we present a novel EMG-based assistive control strategy for lower-limb exoskeletons. An active pelvis orthosis (APO) generates torque profiles for the hip flexion motion assistance, according to the Gastrocnemius Medialis EMG signal. The strategy has been tested on one healthy subject: experimental results show that the user is able to reduce his muscular activation when the assistance is switched on with respect to the free walking condition.

Measuring the effectiveness of ramp metering strategies on I-12.

DOT National Transportation Integrated Search

2013-10-01

Ramp metering is one of the successful traffic control strategies in the area of active traffic and demand management. This study evaluates the : effectiveness of a fixed time ramp metering control on the day to day operation of traffic over two segm...

The influence of coping strategies on subsequent well-being in older patients with cancer: A comparison with 2 control groups.

PubMed

Baitar, Abdelbari; Buntinx, Frank; De Burghgraeve, Tine; Deckx, Laura; Schrijvers, Dirk; Wildiers, Hans; van den Akker, Marjan

2018-03-01

To evaluate dispositional coping strategies as predictors for changes in well-being after 1 year in older patients with cancer (OCP) and 2 control groups. OCP were compared with 2 control groups: middle-aged patients with cancer (MCP) (aging effect) and older patients without cancer (ONC) (cancer effect). Patients were interviewed shortly after a cancer diagnosis and 1 year later. Dispositional coping was measured with the Short Utrecht Coping List. For well-being, we considered psychological well-being (depression, loneliness, distress) and physical health (fatigue, ADL, IADL). Logistic regression analyses were performed to study baseline coping as predictor for subsequent well-being while controlling for important baseline covariates. A total of 1245 patients were included in the analysis at baseline: 263 OCP, 590 ONC, and 392 MCP. Overall, active tackling was employed most often. With the exception of palliative reacting, OCP utilized each coping strategy less frequently than MCP. At 1-year follow-up, 833 patients (66.9%) were interviewed. Active coping strategies (active tackling and seeking social support) predicted subsequent well-being only in MCP. Avoidance coping strategies did not predict well-being in any of the patient groups. Palliative reacting predicted distress in OCP; depression and dependency for ADL in MCP. Coping strategies influence subsequent well-being in patients with cancer, but the impact is different in the age groups. Palliative reacting was the only coping strategy that predicted well-being (ie, distress) in OCP and is therefore, especially in this population, a target for coping skill interventions. Copyright © 2017 John Wiley & Sons, Ltd.

Fuzzy control for nonlinear structure with semi-active friction damper

NASA Astrophysics Data System (ADS)

Zhao, Da-Hai; Li, Hong-Nan

2007-04-01

The implementation of semi-active friction damper for vibration mitigation of seismic structure generally requires an efficient control strategy. In this paper, the fuzzy logic based on Takagi-Sugeno model is proposed for controlling a semi-active friction damper that is installed on a nonlinear building subjected to strong earthquakes. The continuous Bouc-Wen hysteretic model for the stiffness is used to describe nonlinear characteristic of the building. The optimal sliding force with friction damper is determined by nonlinear time history analysis under normal earthquakes. The Takagi-Sugeno fuzzy logic model is employed to adjust the clamping force acted on the friction damper according to the semi-active control strategy. Numerical simulation results demonstrate that the proposed method is very efficient in reducing the peak inter-story drift and acceleration of the nonlinear building structure under earthquake excitations.

Muscle Co-activation: Definitions, Mechanisms, and Functions.

PubMed

Latash, Mark L

2018-03-28

The phenomenon of agonist-antagonist muscle co-activation is discussed with respect to its consequences for movement mechanics (such as increasing joint apparent stiffness, facilitating faster movements, and effects on action stability), implication for movement optimization, and involvement of different neurophysiological structures. Effects of co-activation on movement stability are ambiguous and depend on the effector representing a kinematic chain with a fixed origin or free origin. Further, co-activation is discussed within the framework of the equilibrium-point hypothesis and the idea of hierarchical control with spatial referent coordinates. Relations of muscle co-activation to changes in one of the basic commands, the c-command, are discussed and illustrated. A hypothesis is suggested that agonist-antagonist co-activation reflects a deliberate neural control strategy to preserve effector-level control and avoid making it degenerate and facing the necessity to control at the level of signals to individual muscles. This strategy, in particular, allows stabilizing motor actions by co-varied adjustments in spaces of control variables. This hypothesis is able to account for higher levels of co-activation in young healthy persons performing challenging tasks and across various populations with movement impairments.

Ventral Striatum and the Evaluation of Memory Retrieval Strategies

PubMed Central

Badre, David; Lebrecht, Sophie; Pagliaccio, David; Long, Nicole M.; Scimeca, Jason M.

2015-01-01

Adaptive memory retrieval requires mechanisms of cognitive control that facilitate the recovery of goal-relevant information. Frontoparietal systems are known to support control of memory retrieval. However, the mechanisms by which the brain acquires, evaluates, and adapts retrieval strategies remain unknown. Here, we provide evidence that ventral striatal activation tracks the success of a retrieval strategy and correlates with subsequent reliance on that strategy. Human participants were scanned with fMRI while performing a lexical decision task. A rule was provided that indicated the likely semantic category of a target word given the category of a preceding prime. Reliance on the rule improved decision-making, as estimated within a drift diffusion framework. Ventral striatal activation tracked the benefit that relying on the rule had on decision-making. Moreover, activation in ventral striatum correlated with a participant’s subsequent reliance on the rule. Taken together, these results support a role for ventral striatum in learning and evaluating declarative retrieval strategies. PMID:24564466

A compound control strategy combining velocity compensation with ADRC of electro-hydraulic position servo control system.

PubMed

Gao, Bingwei; Shao, Junpeng; Yang, Xiaodong

2014-11-01

In order to enhance the anti-jamming ability of electro-hydraulic position servo control system at the same time improve the control precision of the system, a compound control strategy that combines velocity compensation with Active Disturbance Rejection Controller (ADRC) is proposed, and the working principle of the compound control strategy is given. ADRC controller is designed, and the extended state observer is used for observing internal parameters uncertainties and external disturbances, so that the disturbances of the system are suppressed effectively. Velocity compensation controller is designed and the compensation model is derived to further improve the positioning accuracy of the system and to achieve the velocity compensation without disturbance. The compound control strategy is verified by the simulation and experiment respectively, and the simulation and experimental results show that the electro-hydraulic position servo control system with ADRC controller can effectively inhibit the external disturbances, the precise positioning control is realized after introducing the velocity compensation controller, and verify that the compound control strategy is effective. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Active Traffic Management: Comprehension, Legibility, Distance, and Motorist Behavior In Response to Selected Variable Speed Limit and Lane Control Signing

DOT National Transportation Integrated Search

2016-06-01

Active traffic management (ATM) incorporates a collection of strategies allowing the dynamic management of recurrent and nonrecurrent congestion based on prevailing traffic conditions. These strategies help to increase peak capacity, smooth traffic f...

Fungal Spoilage in Food Processing.

PubMed

Snyder, Abigail B; Worobo, Randy W

2018-06-01

Food processing, packaging, and formulation strategies are often specifically designed to inhibit or control microbial growth to prevent spoilage. Some of the most restrictive strategies rely solely or on combinations of pH reduction, preservatives, water activity limitation, control of oxygen tension, thermal processing, and hermetic packaging. In concert, these strategies are used to inactivate potential spoilage microorganisms or inhibit their growth. However, for select microbes that can overcome these controls, the lack of competition from additional background microbiota helps facilitate their propagation.

Benchmark simulation model no 2: general protocol and exploratory case studies.

PubMed

Jeppsson, U; Pons, M-N; Nopens, I; Alex, J; Copp, J B; Gernaey, K V; Rosen, C; Steyer, J-P; Vanrolleghem, P A

2007-01-01

Over a decade ago, the concept of objectively evaluating the performance of control strategies by simulating them using a standard model implementation was introduced for activated sludge wastewater treatment plants. The resulting Benchmark Simulation Model No 1 (BSM1) has been the basis for a significant new development that is reported on here: Rather than only evaluating control strategies at the level of the activated sludge unit (bioreactors and secondary clarifier) the new BSM2 now allows the evaluation of control strategies at the level of the whole plant, including primary clarifier and sludge treatment with anaerobic sludge digestion. In this contribution, the decisions that have been made over the past three years regarding the models used within the BSM2 are presented and argued, with particular emphasis on the ADM1 description of the digester, the interfaces between activated sludge and digester models, the included temperature dependencies and the reject water storage. BSM2-implementations are now available in a wide range of simulation platforms and a ring test has verified their proper implementation, consistent with the BSM2 definition. This guarantees that users can focus on the control strategy evaluation rather than on modelling issues. Finally, for illustration, twelve simple operational strategies have been implemented in BSM2 and their performance evaluated. Results show that it is an interesting control engineering challenge to further improve the performance of the BSM2 plant (which is the whole idea behind benchmarking) and that integrated control (i.e. acting at different places in the whole plant) is certainly worthwhile to achieve overall improvement.

Linear and non-linear systems identification for adaptive control in mechanical applications vibration suppression

NASA Astrophysics Data System (ADS)

Cazzulani, Gabriele; Resta, Ferruccio; Ripamonti, Francesco

2012-04-01

During the last years, more and more mechanical applications saw the introduction of active control strategies. In particular, the need of improving the performances and/or the system health is very often associated to vibration suppression. This goal can be achieved considering both passive and active solutions. In this sense, many active control strategies have been developed, such as the Independent Modal Space Control (IMSC) or the resonant controllers (PPF, IRC, . . .). In all these cases, in order to tune and optimize the control strategy, the knowledge of the system dynamic behaviour is very important and it can be achieved both considering a numerical model of the system or through an experimental identification process. Anyway, dealing with non-linear or time-varying systems, a tool able to online identify the system parameters becomes a key-point for the control logic synthesis. The aim of the present work is the definition of a real-time technique, based on ARMAX models, that estimates the system parameters starting from the measurements of piezoelectric sensors. These parameters are returned to the control logic, that automatically adapts itself to the system dynamics. The problem is numerically investigated considering a carbon-fiber plate model forced through a piezoelectric patch.

Design and Control of a New Biomimetic Transfemoral Knee Prosthesis Using an Echo-Control Scheme

PubMed Central

2018-01-01

Passive knee prostheses require a significant amount of additional metabolic energy to carry out a gait cycle, therefore affecting the natural human walk performance. Current active knee prostheses are still limited because they do not reply with accuracy of the natural human knee movement, and the time response is relatively large. This paper presents the design and control of a new biomimetic-controlled transfemoral knee prosthesis based on a polycentric-type mechanism. The aim was to develop a knee prosthesis able to provide additional power and to mimic with accuracy of the natural human knee movement using a stable control strategy. The design of the knee mechanism was obtained from the body-guidance kinematics synthesis based on real human walking patterns obtained from computer vision and 3D reconstruction. A biomechanical evaluation of the synthesized prosthesis was then carried out. For the activation and control of the prosthesis, an echo-control strategy was proposed and developed. In this echo-control strategy, the sound side leg is sensed and synchronized with the activation of the knee prosthesis. An experimental prototype was built and evaluated in a test rig. The results revealed that the prosthetic knee is able to mimic the biomechanics of the human knee. PMID:29854368

Learning Goals and Strategies in the Self-regulation of Learning

ERIC Educational Resources Information Center

Gaeta Gonzalez, Martha Leticia

2013-01-01

In order to self-regulate their learning, students need to use different strategies to plan, monitor, and evaluate their learning activities (meta-cognitive strategies), as well as to control their motivation and emotion (volitional strategies). Students' effectiveness in their self-regulated learning process also varies depending on the academic…

Nuclear Strategy and World Order: The United States Imperative.

ERIC Educational Resources Information Center

Beres, Louis Rene

The current U.S. nuclear strategy goes beyond the legitimate objective of survivable strategic forces to active preparation for nuclear war. The Reagan administration strategy rejects minimum deterrence and prepares for a nuclear war that might be protracted and controlled. The strategy reflects the understanding that a combination of counterforce…

Landing strategies focusing on the control of tibial rotation in the initial contact period of one-leg forward hops.

PubMed

Chen, W-L; Chen, Y-T; Huang, S-Y; Yang, C-Y; Wu, C-D; Chang, C-W

2017-08-01

Anterior cruciate ligament (ACL) reconstruction (ACLR) surgeries successfully restore anterior tibial translation but not tibial rotation. This study aimed to explore landing strategies focusing on the control of tibial rotation at landing when the ACL is most vulnerable. Three groups of male subjects (50 ACLRs, 26 basketball players, and 31 controls) participated in one-leg forward hop tests for determining the tibial rotatory landing strategies adopted during the initial landing phase. The differences in knee kinematics and muscle activities between internal and external tibial rotatory (ITR, ETR) landing strategies were examined. A higher proportion of basketball players (34.6%) were found to adopt ITR strategies (controls: 6.5%), exhibiting significantly greater hopping distance and knee strength. After adjusting for hopping distance, subjects adopting ITR strategies were found to hop faster with straighter knees at foot contact and with greater ITR and less knee adduction angular displacement during the initial landing phase. However, significantly greater angular displacement in knee flexion, greater medial hamstring activities, and greater co-contraction index of hamstrings and medial knee muscles were also found during initial landing. Our results support the importance of the recruitments of medial hamstrings or the local co-contraction in assisting the rotatory control of the knee during initial landing for avoiding ACL injuries. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Intermittent control with ankle, hip, and mixed strategies during quiet standing: a theoretical proposal based on a double inverted pendulum model.

PubMed

Suzuki, Yasuyuki; Nomura, Taishin; Casadio, Maura; Morasso, Pietro

2012-10-07

Human upright posture, as a mechanical system, is characterized by an instability of saddle type, involving both stable and unstable dynamic modes. The brain stabilizes such system by generating active joint torques, according to a time-delayed neural feedback control. What is still unsolved is a clear understanding of the control strategies and the control mechanisms that are used by the central nervous system in order to stabilize the unstable posture in a robust way while maintaining flexibility. Most studies in this direction have been limited to the single inverted pendulum model, which is useful for formalizing fundamental mechanical aspects but insufficient for addressing more general issues concerning neural control strategies. Here we consider a double inverted pendulum model in the sagittal plane with small passive viscoelasticity at the ankle and hip joints. Despite difficulties in stabilizing the double pendulum model in the presence of the large feedback delay, we show that robust and flexible stabilization of the upright posture can be established by an intermittent control mechanism that achieves the goal of stabilizing the body posture according to a "divide and conquer strategy", which switches among different controllers in different parts of the state space of the double inverted pendulum. Remarkably, it is shown that a global, robust stability is achieved even if the individual controllers are unstable and the information exploited for switching from one controller to another is severely delayed, as it happens in biological reality. Moreover, the intermittent controller can automatically resolve coordination among multiple active torques associated with the muscle synergy, leading to the emergence of distinct temporally coordinated active torque patterns, referred to as the intermittent ankle, hip, and mixed strategies during quiet standing, depending on the passive elasticity at the hip joint. Copyright © 2012 Elsevier Ltd. All rights reserved.

Generation of Tutorial Dialogues: Discourse Strategies for Active Learning

DTIC Science & Technology

1998-05-29

AND SUBTITLE Generation of Tutorial Dialogues: Discourse Strategies for active Learning AUTHORS Dr. Martha Evens 7. PERFORMING ORGANI2ATION NAME...time the student starts in on a new topic. Michael and Rovick constantly attempt to promote active learning . They regularly use hints and only resort...Controlling active learning : How tutors decide when to generate hints. Proceedings of FLAIRS 󈨣. Melbourne Beach, FL. 157-161. Hume, G., Michael

Fault-Tolerant Control of ANPC Three-Level Inverter Based on Order-Reduction Optimal Control Strategy under Multi-Device Open-Circuit Fault.

PubMed

Xu, Shi-Zhou; Wang, Chun-Jie; Lin, Fang-Li; Li, Shi-Xiang

2017-10-31

The multi-device open-circuit fault is a common fault of ANPC (Active Neutral-Point Clamped) three-level inverter and effect the operation stability of the whole system. To improve the operation stability, this paper summarized the main solutions currently firstly and analyzed all the possible states of multi-device open-circuit fault. Secondly, an order-reduction optimal control strategy was proposed under multi-device open-circuit fault to realize fault-tolerant control based on the topology and control requirement of ANPC three-level inverter and operation stability. This control strategy can solve the faults with different operation states, and can works in order-reduction state under specific open-circuit faults with specific combined devices, which sacrifices the control quality to obtain the stability priority control. Finally, the simulation and experiment proved the effectiveness of the proposed strategy.

Multi-load Groups Coordinated Load Control Strategy Considering Power Network Constraints

NASA Astrophysics Data System (ADS)

Liu, Meng; Zhao, Binchao; Wang, Jun; Zhang, Guohui; Wang, Xin

2017-05-01

Loads with energy storage property can actively participate in power balance for power systems, this paper takes air conditioner as a controllable load example, proposing a multi-load groups coordinated load control strategy considering power network constraints. Firstly, two load control modes considering recovery of load diversity are designed, blocking power oscillation of aggregated air conditioners. As the same time, air conditioner temperature setpoint recovery control strategy is presented to avoid power recovery peak. Considering inherent characteristics of two load control modes, an coordinated load control mode is designed by combining the both. Basing on this, a multi-load groups coordinated load control strategy is proposed. During the implementing of load control, power network constraints should be satisfied. An indice which can reflect the security of power system operating is defined. By minimizing its value through optimization, the change of air conditioning loads’ aggregated power on each load bus can be calculated. Simulations are conducted on an air conditioners group and New England 10-generator 39-bus system, verifying the effectiveness of the proposed multi-load groups coordinated load control strategy considering power network constraints.

Effect of intermittent feedback control on robustness of human-like postural control system

NASA Astrophysics Data System (ADS)

Tanabe, Hiroko; Fujii, Keisuke; Suzuki, Yasuyuki; Kouzaki, Motoki

2016-03-01

Humans have to acquire postural robustness to maintain stability against internal and external perturbations. Human standing has been recently modelled using an intermittent feedback control. However, the causality inside of the closed-loop postural control system associated with the neural control strategy is still unknown. Here, we examined the effect of intermittent feedback control on postural robustness and of changes in active/passive components on joint coordinative structure. We implemented computer simulation of a quadruple inverted pendulum that is mechanically close to human tiptoe standing. We simulated three pairs of joint viscoelasticity and three choices of neural control strategies for each joint: intermittent, continuous, or passive control. We examined postural robustness for each parameter set by analysing the region of active feedback gain. We found intermittent control at the hip joint was necessary for model stabilisation and model parameters affected the robustness of the pendulum. Joint sways of the pendulum model were partially smaller than or similar to those of experimental data. In conclusion, intermittent feedback control was necessary for the stabilisation of the quadruple inverted pendulum. Also, postural robustness of human-like multi-link standing would be achieved by both passive joint viscoelasticity and neural joint control strategies.

Effect of intermittent feedback control on robustness of human-like postural control system.

PubMed

Tanabe, Hiroko; Fujii, Keisuke; Suzuki, Yasuyuki; Kouzaki, Motoki

2016-03-02

Humans have to acquire postural robustness to maintain stability against internal and external perturbations. Human standing has been recently modelled using an intermittent feedback control. However, the causality inside of the closed-loop postural control system associated with the neural control strategy is still unknown. Here, we examined the effect of intermittent feedback control on postural robustness and of changes in active/passive components on joint coordinative structure. We implemented computer simulation of a quadruple inverted pendulum that is mechanically close to human tiptoe standing. We simulated three pairs of joint viscoelasticity and three choices of neural control strategies for each joint: intermittent, continuous, or passive control. We examined postural robustness for each parameter set by analysing the region of active feedback gain. We found intermittent control at the hip joint was necessary for model stabilisation and model parameters affected the robustness of the pendulum. Joint sways of the pendulum model were partially smaller than or similar to those of experimental data. In conclusion, intermittent feedback control was necessary for the stabilisation of the quadruple inverted pendulum. Also, postural robustness of human-like multi-link standing would be achieved by both passive joint viscoelasticity and neural joint control strategies.

Effect of intermittent feedback control on robustness of human-like postural control system

PubMed Central

Tanabe, Hiroko; Fujii, Keisuke; Suzuki, Yasuyuki; Kouzaki, Motoki

2016-01-01

Humans have to acquire postural robustness to maintain stability against internal and external perturbations. Human standing has been recently modelled using an intermittent feedback control. However, the causality inside of the closed-loop postural control system associated with the neural control strategy is still unknown. Here, we examined the effect of intermittent feedback control on postural robustness and of changes in active/passive components on joint coordinative structure. We implemented computer simulation of a quadruple inverted pendulum that is mechanically close to human tiptoe standing. We simulated three pairs of joint viscoelasticity and three choices of neural control strategies for each joint: intermittent, continuous, or passive control. We examined postural robustness for each parameter set by analysing the region of active feedback gain. We found intermittent control at the hip joint was necessary for model stabilisation and model parameters affected the robustness of the pendulum. Joint sways of the pendulum model were partially smaller than or similar to those of experimental data. In conclusion, intermittent feedback control was necessary for the stabilisation of the quadruple inverted pendulum. Also, postural robustness of human-like multi-link standing would be achieved by both passive joint viscoelasticity and neural joint control strategies. PMID:26931281

Auto-phosphorylation Represses Protein Kinase R Activity.

PubMed

Wang, Die; de Weerd, Nicole A; Willard, Belinda; Polekhina, Galina; Williams, Bryan R G; Sadler, Anthony J

2017-03-10

The central role of protein kinases in controlling disease processes has spurred efforts to develop pharmaceutical regulators of their activity. A rational strategy to achieve this end is to determine intrinsic auto-regulatory processes, then selectively target these different states of kinases to repress their activation. Here we investigate auto-regulation of the innate immune effector protein kinase R, which phosphorylates the eukaryotic initiation factor 2α to inhibit global protein translation. We demonstrate that protein kinase R activity is controlled by auto-inhibition via an intra-molecular interaction. Part of this mechanism of control had previously been reported, but was then controverted. We account for the discrepancy and extend our understanding of the auto-inhibitory mechanism by identifying that auto-inhibition is paradoxically instigated by incipient auto-phosphorylation. Phosphor-residues at the amino-terminus instigate an intra-molecular interaction that enlists both of the N-terminal RNA-binding motifs of the protein with separate surfaces of the C-terminal kinase domain, to co-operatively inhibit kinase activation. These findings identify an innovative mechanism to control kinase activity, providing insight for strategies to better regulate kinase activity.

Strategies in probabilistic feedback learning in Parkinson patients OFF medication.

PubMed

Bellebaum, C; Kobza, S; Ferrea, S; Schnitzler, A; Pollok, B; Südmeyer, M

2016-04-21

Studies on classification learning suggested that altered dopamine function in Parkinson's Disease (PD) specifically affects learning from feedback. In patients OFF medication, enhanced learning from negative feedback has been described. This learning bias was not seen in observational learning from feedback, indicating different neural mechanisms for this type of learning. The present study aimed to compare the acquisition of stimulus-response-outcome associations in PD patients OFF medication and healthy control subjects in active and observational learning. 16 PD patients OFF medication and 16 controls were examined with three parallel learning tasks each, two feedback-based (active and observational) and one non-feedback-based paired associates task. No acquisition deficit was seen in the patients for any of the tasks. More detailed analyses on the learning strategies did, however, reveal that the patients showed more lose-shift responses during active feedback learning than controls, and that lose-shift and win-stay responses more strongly determined performance accuracy in patients than controls. For observational feedback learning, the performance of both groups correlated similarly with the performance in non-feedback-based paired associates learning and with the accuracy of observed performance. Also, patients and controls showed comparable evidence of feedback processing in observational learning. In active feedback learning, PD patients use alternative learning strategies than healthy controls. Analyses on observational learning did not yield differences between patients and controls, adding to recent evidence of a differential role of the human striatum in active and observational learning from feedback. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Hand hygiene promotion and the participation of infection control link nurses: an effective innovation to overcome campaign fatigue.

PubMed

Seto, Wing Hong; Yuen, Shanny W S; Cheung, Christina W Y; Ching, Patricia T Y; Cowling, Benjamin J; Pittet, Didier

2013-12-01

Campaign fatigue was evident in a large hospital in Hong Kong when hand hygiene compliance remained just above 50% after 4 years of aggressive and varied promotional activities. A new innovative strategy was developed that directly involved the infection control link nurses both in formulating the strategy and in implementing the various proposed programs. The new strategy was successful in increasing hand hygiene compliance to 83%. Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Strategy for increasing the participation of masyarakat peduli api in forest fire control

NASA Astrophysics Data System (ADS)

Ni’mah, N. L. K.; Herdiansyah, H.; Soesilo, T. E. B.; Mutia, E. F.

2018-03-01

Forest fires have negative impact on ecology, health, and damage economic activities. One of conservation areas facing the threat of forest fire is Gunung Ciremai National Park. This research aims to formulate a strategy to increase the participation of Masyarakat Peduli Api in the effort of forest fire control. This research use quantitative method with SWOT analysis. Expert consisting of representatives from the national park, Ministry of Environment and Forestry, and BPBD Kuningan Regency. An alternative strategy based on SWOT analysis is in quadrant 1 with coordinate point (0,39; 1,23). The position shows that sustainability of national park management through forest fire control can be done with an aggressive strategy. That is maximizing the strength that is owned with its potential as an ecotourism area to increase community motivation to engage in forest fire control activities. Provision of tourism management licenses will create employment opportunities and increase income for the community so it is expected to increase community participation to prevent the occurrence of forest fires rather than forest fire prevention.

Experiments in advanced control concepts for space robotics - An overview of the Stanford Aerospace Robotics Laboratory

NASA Technical Reports Server (NTRS)

Hollars, M. G.; Cannon, R. H., Jr.; Alexander, H. L.; Morse, D. F.

1987-01-01

The Stanford University Aerospace Robotics Laboratory is actively developing and experimentally testing advanced robot control strategies for space robotic applications. Early experiments focused on control of very lightweight one-link manipulators and other flexible structures. The results are being extended to position and force control of mini-manipulators attached to flexible manipulators and multilink manipulators with flexible drive trains. Experimental results show that end-point sensing and careful dynamic modeling or adaptive control are key to the success of these control strategies. Free-flying space robot simulators that operate on an air cushion table have been built to test control strategies in which the dynamics of the base of the robot and the payload are important.

A neuromechanical strategy for mediolateral foot placement in walking humans.

PubMed

Rankin, Bradford L; Buffo, Stephanie K; Dean, Jesse C

2014-07-15

Stability is an important concern during human walking and can limit mobility in clinical populations. Mediolateral stability can be efficiently controlled through appropriate foot placement, although the underlying neuromechanical strategy is unclear. We hypothesized that humans control mediolateral foot placement through swing leg muscle activity, basing this control on the mechanical state of the contralateral stance leg. Participants walked under Unperturbed and Perturbed conditions, in which foot placement was intermittently perturbed by moving the right leg medially or laterally during the swing phase (by ∼50-100 mm). We quantified mediolateral foot placement, electromyographic activity of frontal-plane hip muscles, and stance leg mechanical state. During Unperturbed walking, greater swing-phase gluteus medius (GM) activity was associated with more lateral foot placement. Increases in GM activity were most strongly predicted by increased mediolateral displacement between the center of mass (CoM) and the contralateral stance foot. The Perturbed walking results indicated a causal relationship between stance leg mechanics and swing-phase GM activity. Perturbations that reduced the mediolateral CoM displacement from the stance foot caused reductions in swing-phase GM activity and more medial foot placement. Conversely, increases in mediolateral CoM displacement caused increased swing-phase GM activity and more lateral foot placement. Under both Unperturbed and Perturbed conditions, humans controlled their mediolateral foot placement by modulating swing-phase muscle activity in response to the mechanical state of the contralateral leg. This strategy may be disrupted in clinical populations with a reduced ability to modulate muscle activity or sense their body's mechanical state.

A cluster-randomized controlled trial of strategies to increase adolescents' physical activity and motivation during physical education lessons: the Motivating Active Learning in Physical Education (MALP) trial.

PubMed

Rosenkranz, Richard R; Lubans, David R; Peralta, Louisa R; Bennie, Andrew; Sanders, Taren; Lonsdale, Chris

2012-10-01

The physical activity (PA) levels of many children and adolescents in Australia are currently insufficient to promote health benefits. Physical education (PE) programs aim to promote PA and reach nearly all school-aged children, but PA levels within PE lessons are often low. PE teachers may influence children's motivation to be physically active in PE lessons, but little is known about teacher strategies that effectively motivate children to participate in PA, and few intervention studies have examined motivational strategies in PE. The purpose of this study was to compare the effect of three motivational strategies, each based on Self-Determination Theory (SDT), on PA levels, and their hypothesized antecedents, during year 8 PE lessons. This study employed a cluster-randomized controlled trial design. Following a familiarization session, PA levels and hypothesized PA antecedents were measured during a baseline lesson and a post-intervention or control lesson. Teachers (n = 16) and their classes from five secondary schools in Sydney, Australia were randomly assigned into four blocks and instructed to provide one of four 20-min lesson teaching strategy conditions: (1) explaining the relevance of activities; (2) providing choice from PA options selected by the teacher; (3) providing equipment and free choice of activities; or (4) usual practice. The primary outcomes were lesson time spent in moderate-to-vigorous PA, and motivation towards the lesson. Secondary outcomes were perceptions of teacher behavior, psychological needs satisfaction, and lesson time spent in sedentary behavior. PA and sedentary behavior were measured during baseline and post-intervention lessons with waist-mounted Actigraph GT3X accelerometers. Teacher behavior, psychological needs satisfaction, and motivation were assessed via questionnaires at the end of each lesson. Linear mixed-model analyses will be run on all outcomes, with students nested within teachers as a random effect. Study findings will inform the development of effective SDT-based teaching strategy interventions to enhance students' psychological needs satisfaction, motivation, and PA levels. More effective teaching strategies may be identified that are capable of improving adolescents' PA levels, and thereby provide beneficial population health outcomes. This trial is registered with Current Controlled Trials and is traceable as ISRCTN07038258.

A cluster-randomized controlled trial of strategies to increase adolescents’ physical activity and motivation during physical education lessons: the Motivating Active Learning in Physical Education (MALP) trial

PubMed Central

2012-01-01

Background The physical activity (PA) levels of many children and adolescents in Australia are currently insufficient to promote health benefits. Physical education (PE) programs aim to promote PA and reach nearly all school-aged children, but PA levels within PE lessons are often low. PE teachers may influence children’s motivation to be physically active in PE lessons, but little is known about teacher strategies that effectively motivate children to participate in PA, and few intervention studies have examined motivational strategies in PE. The purpose of this study was to compare the effect of three motivational strategies, each based on Self-Determination Theory (SDT), on PA levels, and their hypothesized antecedents, during year 8 PE lessons. Methods/design This study employed a cluster-randomized controlled trial design. Following a familiarization session, PA levels and hypothesized PA antecedents were measured during a baseline lesson and a post-intervention or control lesson. Teachers (n = 16) and their classes from five secondary schools in Sydney, Australia were randomly assigned into four blocks and instructed to provide one of four 20-min lesson teaching strategy conditions: (1) explaining the relevance of activities; (2) providing choice from PA options selected by the teacher; (3) providing equipment and free choice of activities; or (4) usual practice. The primary outcomes were lesson time spent in moderate-to-vigorous PA, and motivation towards the lesson. Secondary outcomes were perceptions of teacher behavior, psychological needs satisfaction, and lesson time spent in sedentary behavior. PA and sedentary behavior were measured during baseline and post-intervention lessons with waist-mounted Actigraph GT3X accelerometers. Teacher behavior, psychological needs satisfaction, and motivation were assessed via questionnaires at the end of each lesson. Linear mixed-model analyses will be run on all outcomes, with students nested within teachers as a random effect. Discussion Study findings will inform the development of effective SDT-based teaching strategy interventions to enhance students’ psychological needs satisfaction, motivation, and PA levels. More effective teaching strategies may be identified that are capable of improving adolescents’ PA levels, and thereby provide beneficial population health outcomes. Trial registration This trial is registered with Current Controlled Trials and is traceable as ISRCTN07038258. PMID:23025261

The Coach2Move Approach: Development and Acceptability of an Individually Tailored Physical Therapy Strategy to Increase Activity Levels in Older Adults With Mobility Problems.

PubMed

de Vries, Nienke M; van Ravensberg, C Dorine; Hobbelen, Johannes S M; van der Wees, Philip J; Olde Rikkert, Marcel G M; Staal, J Bart; Nijhuis-van der Sanden, Maria W G

2015-01-01

Despite the positive effects of physical activity on numerous aspects of health, many older adults remain sedentary even after participating in physical activity interventions. Standardized exercise programs do not necessarily bring about the behavioral change that is necessary. Therefore, a patient-centered approach is needed. The purpose of this study was to develop and assess the acceptability and potential effectiveness of the Coach2Move strategy; a physical therapy (PT) approach aimed at improving the long-term level of physical activity in mobility-limited older adults. The Coach2Move strategy was developed on the basis of 2 systematic literature studies and expert consultations. Multiple focus group meetings and a Delphi procedure were organized to gain consensus on the Coach2Move strategy. Acceptability and potential effectiveness were studied in a pilot study with a pre-/postdesign in which 2 physical therapists and 12 patients participated. To assess acceptability, patients were interviewed, discussion were held with the involved physical therapists was held, and health records were studied. Potential effectiveness was tested measuring the level of physical activity, frailty, quality of life, and mobility before and after treatment. On the basis of the literature study and expert consultations, an algorithm based on the Hypothesis Oriented Algorithm for Clinicians Part II was developed: the Coach2Move approach. Key elements of the Coach2Move approach include an extensive intake using motivational interviewing, clinical reasoning, coaching to increase physical activity and self-management, focusing on meaningful activities, and working according to 3 patient-tailored intervention profiles with a predefined number of sessions. The pilot study showed high appraisal of the strategy by both physical therapists and patients. Moreover, a potential effect on the level of physical activity, frailty, quality of life, and mobility was observed. Because the pilot study was not randomized or controlled and included a small sample, no conclusions can be drawn about the effectiveness of the Coach2Move strategy. However, all suggestions made in this study were implemented in an ongoing, randomized controlled trial in which the Coach2Move strategy will be compared to usual care PT. In conclusion, the Coach2Move strategy can be considered acceptable in PT practice and showed potential benefits. The results on the (cost-)effectiveness of this strategy based on a large, randomized, controlled trial are expected in 2014.

Dynamics and Control of a Quadrotor with Active Geometric Morphing

NASA Astrophysics Data System (ADS)

Wallace, Dustin A.

Quadrotors are manufactured in a wide variety of shapes, sizes, and performance levels to fulfill a multitude of roles. Robodub Inc. has patented a morphing quadrotor which will allow active reconfiguration between various shapes for performance optimization across a wider spectrum of roles. The dynamics of the system are studied and modeled using Newtonian Mechanics. Controls are developed and simulated using both Linear Quadratic and Numerical Nonlinear Optimal control for a symmetric simplificiation of the system dynamics. Various unique vehicle capabilities are investigated, including novel single-throttle flight control using symmetric geometric morphing, as well as recovery from motor loss by reconfiguring into a trirotor configuration. The system dynamics were found to be complex and highly nonlinear. All attempted control strategies resulted in controllability, suggesting further research into each may lead to multiple viable control strategies for a physical prototype.

Effects of an intervention in active strategies for text comprehension and recall.

PubMed

Elosúa, M Rosa; García-Madruga, Juan A; Gutiérrez, Francisco; Luque, Juan Luis; Gárate, Milagros

2002-11-01

The aim of this study was to investigate the effects of an intervention program to promote active text-processing strategies (main-idea identification and summarization) at two developmental levels (12- and 16-year-olds). The independent variables were training condition (experimental and control) and school level (7th and 10th grades). Several measures were taken as dependent variables: reading span, reading time, construction of macrostructure, and structural recall. The hypothesis claimed that training would increase comprehension and recall significantly. Furthermore, as a result of the training program, a reduction in developmental differences in the experimental groups at posttest was also expected. Results supported the predictions, showing a significant improvement in the experimental groups' reading comprehension and recall. These results are discussed in terms of the importance of active and self-controlled strategies for text comprehension and recall.

Functional-anatomic correlates of individual differences in memory.

PubMed

Kirchhoff, Brenda A; Buckner, Randy L

2006-07-20

Memory abilities differ greatly across individuals. To explore a source of these differences, we characterized the varied strategies people adopt during unconstrained encoding. Participants intentionally encoded object pairs during functional MRI. Principal components analysis applied to a strategy questionnaire revealed that participants variably used four main strategies to aid learning. Individuals' use of verbal elaboration and visual inspection strategies independently correlated with their memory performance. Verbal elaboration correlated with activity in a network of regions that included prefrontal regions associated with controlled verbal processing, while visual inspection correlated with activity in a network of regions that included an extrastriate region associated with object processing. Activity in regions associated with use of these strategies was also correlated with memory performance. This study reveals functional-anatomic correlates of verbal and perceptual strategies that are variably used by individuals during encoding. These strategies engage distinct brain regions and may separately influence memory performance.

Low authority-threshold control for large flexible structures

NASA Technical Reports Server (NTRS)

Zimmerman, D. C.; Inman, D. J.; Juang, J.-N.

1988-01-01

An improved active control strategy for the vibration control of large flexible structures is presented. A minimum force, low authority-threshold controller is developed to bring a system with or without known external disturbances back into an 'allowable' state manifold over a finite time interval. The concept of a constrained, or allowable feedback form of the controller is introduced that reflects practical hardware implementation concerns. The robustness properties of the control strategy are then assessed. Finally, examples are presented which highlight the key points made within the paper.

Controlling lymphatic filariasis and soil-transmitted helminthiasis together in South Asia: opportunities and challenges.

PubMed

Padmasiri, E A; Montresor, A; Biswas, G; de Silva, N R

2006-09-01

Lymphatic filariasis (LF) and the major soil-transmitted helminth (STH) infections are co-endemic in many countries, particularly in Asia. Control strategies for both groups of infections have increasingly focused on the use of mass chemotherapy. With the use of albendazole, there is now a tool that is common to both. However, there are also important differences in their modes of transmission and epidemiology, and, as a result, in the overall control strategies. The Global Programme for the Elimination of Lymphatic Filariasis aims to eliminate LF through time-limited mass drug administration programmes. Control activities for STH are more diffuse, aiming to piggy-back de-worming onto existing services, such as school health activities; controlling morbidity, rather than eliminating infection, is the stated goal. In order to maximize health benefits to communities that are endemic for one or both of these infections, it is vitally important that policy makers and programme managers have a clear understanding of both commonalities and differences, and implement control strategies that allocate available resources in an optimal manner.

Active tuning of vibration and wave propagation in elastic beams with periodically placed piezoelectric actuator/sensor pairs

NASA Astrophysics Data System (ADS)

Li, Fengming; Zhang, Chuanzeng; Liu, Chunchuan

2017-04-01

A novel strategy is proposed to actively tune the vibration and wave propagation properties in elastic beams. By periodically placing the piezoelectric actuator/sensor pairs along the beam axis, an active periodic beam structure which exhibits special vibration and wave propagation properties such as the frequency pass-bands and stop-bands (or band-gaps) is developed. Hamilton's principle is applied to establish the equations of motion of the sub-beam elements i.e. the unit-cells, bonded by the piezoelectric patches. A negative proportional feedback control strategy is employed to design the controllers which can provide a positive active stiffness to the beam for a positive feedback control gain, which can increase the stability of the structural system. By means of the added positive active stiffness, the periodicity or the band-gap property of the beam with periodically placed piezoelectric patches can be actively tuned. From the investigation, it is shown that better band-gap characteristics can be achieved by using the negative proportional feedback control. The band-gaps can be obviously broadened by properly increasing the control gain, and they can also be greatly enlarged by appropriately designing the structural sizes of the controllers. The control voltages applied on the piezoelectric actuators are in reasonable and controllable ranges, especially, they are very low in the band-gaps. Thus, the vibration and wave propagation behaviors of the elastic beam can be actively controlled by the periodically placed piezoelectric patches.

Ankle and hip postural strategies defined by joint torques

NASA Technical Reports Server (NTRS)

Runge, C. F.; Shupert, C. L.; Horak, F. B.; Zajac, F. E.; Peterson, B. W. (Principal Investigator)

1999-01-01

Previous studies have identified two discrete strategies for the control of posture in the sagittal plane based on EMG activations, body kinematics, and ground reaction forces. The ankle strategy was characterized by body sway resembling a single-segment-inverted pendulum and was elicited on flat support surfaces. In contrast, the hip strategy was characterized by body sway resembling a double-segment inverted pendulum divided at the hip and was elicited on short or compliant support surfaces. However, biomechanical optimization models have suggested that hip strategy should be observed in response to fast translations on a flat surface also, provided the feet are constrained to remain in contact with the floor and the knee is constrained to remain straight. The purpose of this study was to examine the experimental evidence for hip strategy in postural responses to backward translations of a flat support surface and to determine whether analyses of joint torques would provide evidence for two separate postural strategies. Normal subjects standing on a flat support surface were translated backward with a range of velocities from fast (55 cm/s) to slow (5 cm/s). EMG activations and joint kinematics showed pattern changes consistent with previous experimental descriptions of mixed hip and ankle strategy with increasing platform velocity. Joint torque analyses revealed the addition of a hip flexor torque to the ankle plantarflexor torque during fast translations. This finding indicates the addition of hip strategy to ankle strategy to produce a continuum of postural responses. Hip torque without accompanying ankle torque (pure hip strategy) was not observed. Although postural control strategies have previously been defined by how the body moves, we conclude that joint torques, which indicate how body movements are produced, are useful in defining postural control strategies. These results also illustrate how the biomechanics of the body can transform discrete control patterns into a continuum of postural corrections.

An Examination of Stimulus Control in Fluency-Based Strategies: SAFMEDS and Generalization

ERIC Educational Resources Information Center

Meindl, James N.; Ivy, Jonathan W.; Miller, Neal; Neef, Nancy A.; Williamson, Robert L.

2013-01-01

Fluency-based strategies such as Say All Fast a Minute Each Day Shuffled (SAFMEDS) effectively promote fluent responding (i.e., high rate and accuracy). It is possible, however, that the stimulus control developed through these activities inhibits stimulus generalization. We investigated this concern in a two-part study with college students.…

Co-ordination of physiological and morphological responses of stomata to elevated [CO2] in vascular plants.

PubMed

Haworth, Matthew; Elliott-Kingston, Caroline; McElwain, Jennifer C

2013-01-01

Plant stomata display a wide range of short-term behavioural and long-term morphological responses to atmospheric carbon dioxide concentration ([CO(2)]). The diversity of responses suggests that plants may have different strategies for controlling gas exchange, yet it is not known whether these strategies are co-ordinated in some way. Here, we test the hypothesis that there is co-ordination of physiological (via aperture change) and morphological (via stomatal density change) control of gas exchange by plants. We examined the response of stomatal conductance (G(s)) to instantaneous changes in external [CO(2)] (C(a)) in an evolutionary cross-section of vascular plants grown in atmospheres of elevated [CO(2)] (1,500 ppm) and sub-ambient [O(2)] (13.0 %) compared to control conditions (380 ppm CO(2), 20.9 % O(2)). We found that active control of stomatal aperture to [CO(2)] above current ambient levels was not restricted to angiosperms, occurring in the gymnosperms Lepidozamia peroffskyana and Nageia nagi. The angiosperm species analysed appeared to possess a greater respiratory demand for stomatal movement than gymnosperm species displaying active stomatal control. Those species with little or no control of stomatal aperture (termed passive) to C(a) were more likely to exhibit a reduction in stomatal density than species with active stomatal control when grown in atmospheres of elevated [CO(2)]. The relationship between the degree of stomatal aperture control to C(a) above ambient and the extent of any reduction in stomatal density may suggest the co-ordination of physiological and morphological responses of stomata to [CO(2)] in the optimisation of water use efficiency. This trade-off between stomatal control strategies may have developed due to selective pressures exerted by the costs associated with passive and active stomatal control.

Evaluation of the effects of the Arm Light Exoskeleton on movement execution and muscle activities: a pilot study on healthy subjects.

PubMed

Pirondini, Elvira; Coscia, Martina; Marcheschi, Simone; Roas, Gianluca; Salsedo, Fabio; Frisoli, Antonio; Bergamasco, Massimo; Micera, Silvestro

2016-01-23

Exoskeletons for lower and upper extremities have been introduced in neurorehabilitation because they can guide the patient's limb following its anatomy, covering many degrees of freedom and most of its natural workspace, and allowing the control of the articular joints. The aims of this study were to evaluate the possible use of a novel exoskeleton, the Arm Light Exoskeleton (ALEx), for robot-aided neurorehabilitation and to investigate the effects of some rehabilitative strategies adopted in robot-assisted training. We studied movement execution and muscle activities of 16 upper limb muscles in six healthy subjects, focusing on end-effector and joint kinematics, muscle synergies, and spinal maps. The subjects performed three dimensional point-to-point reaching movements, without and with the exoskeleton in different assistive modalities and control strategies. The results showed that ALEx supported the upper limb in all modalities and control strategies: it reduced the muscular activity of the shoulder's abductors and it increased the activity of the elbow flexors. The different assistive modalities favored kinematics and muscle coordination similar to natural movements, but the muscle activity during the movements assisted by the exoskeleton was reduced with respect to the movements actively performed by the subjects. Moreover, natural trajectories recorded from the movements actively performed by the subjects seemed to promote an activity of muscles and spinal circuitries more similar to the natural one. The preliminary analysis on healthy subjects supported the use of ALEx for post-stroke upper limb robotic assisted rehabilitation, and it provided clues on the effects of different rehabilitative strategies on movement and muscle coordination.

Goal setting frequency and the use of behavioral strategies related to diet and physical activity.

PubMed

Nothwehr, Faryle; Yang, Jingzhen

2007-08-01

Goal setting is an effective way to focus attention on behavior change. Theoretically, frequency of goal setting may indicate the level of commitment to diet and physical activity behavior change. Yet, little is known about the association between goal setting frequency and use of specific diet or physical activity-related strategies. This study examines whether changes in goal setting frequency predict changes in use of behavioral strategies over time, controlling for baseline strategy use, demographics and whether a person was trying to lose weight. Data are from a baseline and 1-year follow-up survey of adults in rural Iowa (n = 385). Overall, goal setting frequency was positively associated with use of the strategies measured, at baseline and overtime. Frequent goal setting that is focused specifically on diet or physical activity was more predictive of using dietary or physical activity strategies, respectively, than goal setting focused on weight loss overall. The study provides empirical support for what has been assumed theoretically, that is, frequent goal setting for weight management is an indicator of use of specific behavioral strategies. Significant challenges remain in regard to maintenance of this activity and attainment of weight loss goals.

Neural bases of a specific strategy for visuospatial processing in rugby players.

PubMed

Sekiguchi, Atsushi; Yokoyama, Satoru; Kasahara, Satoshi; Yomogida, Yukihito; Takeuchi, Hikaru; Ogawa, Takeshi; Taki, Yasuyuki; Niwa, Shin-Ichi; Kawashima, Ryuta

2011-10-01

Rugby is one of the most tactically complex sports. Rugby coaching theory suggests that rugby players need to possess various cognitive abilities. A previous study claimed that rugby players have high visuospatial awareness, which is induced by a strategy described as taking a "bird's eye view." To examine if there were differential cortical networks related to visuospatial processing tasks among top-level rugby players and control novices, we compared brain activities during a visuospatial processing task between 20 male top-level rugby players (Top) and 20 control novice males (Novice) using functional magnetic resonance imaging (fMRI). To avoid the effect of differential behavioral performances on brain activation, we recruited novices whose visuospatial ability was expected to match that of the rugby players. We adopted a 3-D mental rotation task during fMRI scanning as a visuospatial processing task. Significantly greater activations from baseline were observed for the Top group than for the Novice group in the right superior parietal lobe and lateral occipital cortex. Significantly greater deactivations from baseline were observed for the Top group than for the Novice group in the right medial prefrontal cortex. The discrepancy between psychobehavioral outputs and the fMRI results suggested the existence of a cognitive strategy among top-level rugby players that differs from that among control novices. The greater activation of the right superior parietal lobe and lateral occipital cortex in top-level rugby players suggested a strategy involving visuospatial cognitive processing with respect to the bird's eye view. In addition, the right medial prefrontal cortex is known to be a part of the default mode networks, suggesting an additional cognitive load for the Top group when using the bird's-eye-view strategy. This further supported the existence of a specific cognitive strategy among top-level rugby players.

Effectiveness of Information Processing Strategy Training on Academic Task Performance in Children with Learning Disabilities: A Pilot Study.

PubMed

Juntorn, Sutinun; Sriphetcharawut, Sarinya; Munkhetvit, Peeraya

2017-01-01

Learning disabilities (LD) can be associated with problems in the four stages of information processing used in learning: input, throughput, output, and feedback. These problems affect the child's ability to learn and perform activities in daily life, especially during academic activities. This study is a pilot study aimed at investigating the effectiveness of information processing strategy training using a combination of two approaches that address the ability to apply processing strategies during academic activities in children with LD. The two approaches are the Perceive, Recall, Plan, and Perform (PRPP) System of Intervention, which is a strategy training intervention, and the Four-Quadrant Model (4QM) of Facilitated Learning approach, which is a systematic facilitator technique. Twenty children with LD were assigned to two groups: the experimental group ( n = 10) and the control group ( n = 10). Children in the experimental group received the intervention twice a week for 6 consecutive weeks. Each treatment session took approximately 50 minutes. Children in the control group received traditional intervention twice a week for 6 consecutive weeks. The results indicated that the combination of the PRPP System of Intervention and the 4QM may improve the participants' ability to apply information processing strategies during academic activities.

Tuning the Catalytic Activity of Subcellular Nanoreactors.

PubMed

Jakobson, Christopher M; Chen, Yiqun; Slininger, Marilyn F; Valdivia, Elias; Kim, Edward Y; Tullman-Ercek, Danielle

2016-07-31

Bacterial microcompartments are naturally occurring subcellular organelles of bacteria and serve as a promising scaffold for the organization of heterologous biosynthetic pathways. A critical element in the design of custom biosynthetic organelles is quantitative control over the loading of heterologous enzymes to the interior of the organelles. We demonstrate that the loading of heterologous proteins to the 1,2-propanediol utilization microcompartment of Salmonella enterica can be controlled using two strategies: by modulating the transcriptional activation of the microcompartment container and by coordinating the expression of the microcompartment container and the heterologous cargo. These strategies allow general control over the loading of heterologous proteins localized by two different N-terminal targeting peptides and represent an important step toward tuning the catalytic activity of bacterial microcompartments for increased biosynthetic productivity. Copyright © 2016. Published by Elsevier Ltd.

Supramolecular Approaches To Control Activity and Selectivity in Hydroformylation Catalysis

PubMed Central

2018-01-01

The hydroformylation reaction is one of the most intensively explored reactions in the field of homogeneous transition metal catalysis, and many industrial applications are known. However, this atom economical reaction has not been used to its full potential, as many selectivity issues have not been solved. Traditionally, the selectivity is controlled by the ligand that is coordinated to the active metal center. Recently, supramolecular strategies have been demonstrated to provide powerful complementary tools to control activity and selectivity in hydroformylation reactions. In this review, we will highlight these supramolecular strategies. We have organized this paper in sections in which we describe the use of supramolecular bidentate ligands, substrate preorganization by interactions between the substrate and functional groups of the ligands, and hydroformylation catalysis in molecular cages. PMID:29657887

Learning an Intermittent Control Strategy for Postural Balancing Using an EMG-Based Human-Computer Interface

PubMed Central

Asai, Yoshiyuki; Tateyama, Shota; Nomura, Taishin

2013-01-01

It has been considered that the brain stabilizes unstable body dynamics by regulating co-activation levels of antagonist muscles. Here we critically reexamined this established theory of impedance control in a postural balancing task using a novel EMG-based human-computer interface, in which subjects were asked to balance a virtual inverted pendulum using visual feedback information on the pendulum's position. The pendulum was actuated by a pair of antagonist joint torques determined in real-time by activations of the corresponding pair of antagonist ankle muscles of subjects standing upright. This motor-task raises a frustrated environment; a large feedback time delay in the sensorimotor loop, as a source of instability, might favor adopting the non-reactive, preprogrammed impedance control, but the ankle muscles are relatively hard to co-activate, which hinders subjects from adopting the impedance control. This study aimed at discovering how experimental subjects resolved this frustrated environment through motor learning. One third of subjects adapted to the balancing task in a way of the impedance-like control. It was remarkable, however, that the majority of subjects did not adopt the impedance control. Instead, they acquired a smart and energetically efficient strategy, in which two muscles were inactivated simultaneously at a sequence of optimal timings, leading to intermittent appearance of periods of time during which the pendulum was not actively actuated. Characterizations of muscle inactivations and the pendulum¡Çs sway showed that the strategy adopted by those subjects was a type of intermittent control that utilizes a stable manifold of saddle-type unstable upright equilibrium that appeared in the state space of the pendulum when the active actuation was turned off. PMID:23717398

Tobacco industry strategy to undermine tobacco control in Finland

PubMed Central

Hiilamo, H

2003-01-01

Objective: To identify and explain tobacco industry strategy in undermining tobacco control measures in Finland and results of these interferences in tobacco policy development during the 1980s and early 1990s. Methods: Tobacco industry documents, which have been publicly available on the internet as a result of litigation in the USA, were analysed. Documents were sought by Finland and by names of organisations and tobacco control activists. Documents were accessed and assessed between September 2000 and November 2002. Tactics of the tobacco industry activities were categorised as presented by Saloojee and Dagli. Results: The international tobacco companies utilised similar strategies in Finland as in other industrial markets to fight tobacco control and legislation, the health advocacy movement, and litigation. These activities slowed down the development and implementation of the Tobacco Act in Finland. However, despite the extensive pressure, the industry was not able to prevent the most progressive tobacco legislation in Europe from being passed and coming into force in Finland in 1977 and in 1995. Conclusion: Denying the health hazards caused by tobacco—despite indisputable scientific evidence—decreased the credibility of the tobacco industry. Strategy of denial was falsely chosen, as health advocacy groups were active both in society and the parliamentary system. The strong influence of the tobacco industry may have in fact increased the visibility of tobacco control in Finland as the litigation process was also drawing attention to negative health effects of tobacco. Therefore the tobacco industry did not manage to convince public opinion. However, the tobacco industry did obtain experience in Finland in how to object to tobacco control measures. PMID:14660780

The role of free-play physical activity in healthy blood glucose maintenance in children with type 1 diabetes mellitus.

PubMed

Marrone, Sonia; Plume, Jessica White; Kerr, Patrick; Pignol, Anna; Vogeltanz-Holm, Nancy; Holm, Jeffrey; Larsen, Margo Adams

2009-01-01

Medical management for children with type 1 diabetes mellitus, including insulin administration to control high blood glucose levels (BGL), is crucial. However, a child-controlled behavioural strategy, like physical activity, to maintain target BGL may be warranted. To demonstrate, pre- and post-activity BGL were collected for 73 children aged 8- to 14-years attending a diabetes camp. Change in BGL across one session of a free-play swimming activity was analysed. Average BGL was significantly reduced from 197.18 mg/dl to 177.78 mg/dl across one 45 min session, and male gender predicted larger reductions. With safety precautions and within the context of appropriate medical management, free-play activity could be used as a strategy for maintaining target BGL.

Long-Term Weight Maintenance Strategies Are Experienced as a Burden by Persons Who Have Lost Weight Compared to Persons with a lifetime Normal, Stable Weight.

PubMed

Kruseman, Maaike; Schmutz, Noémi; Carrard, Isabelle

2017-01-01

To assess dietary intake, eating patterns, physical activity and eating behaviors, and to explore strategies and perceptions of the experience of weight maintenance in weight loss maintainers (weight loss maintenance (WLM) ≥ 10% weight loss maintained for ≥1 year) and in matched controls with a lifetime stable normal weight. Volunteers (32) were recruited by a snowball procedure in this cross-sectional, mixed-methods study. Diet, physical activity, and eating behaviors were assessed with validated questionnaires. Strategies and experiences were investigated during interviews. Descriptive coding, thematic analysis (qualitative data) as well as descriptive analysis and t-tests (quantitative data) were performed. Both groups had similar energy and macronutrient consumption. Those in the WLM group reported higher levels of exercise and scored higher on several dimensions of eating disorders. Four themes - 'food choices,' 'quantities and portion control,' 'physical activity', and 'burden' - emerged from the qualitative data. Both groups used similar weight maintenance strategies, but those in the WLM group experienced a higher burden, expressing effortful control which contrasted with the control group's confidence in their internal cues. Our results show an additional burden related with maintaining weight loss compared to keeping a stable normal weight. They provide evidence to devise interventions that will address the difficulty of regulating intake. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

Subjective well-being in times of social change: congruence of control strategies and perceived control.

PubMed

Grümer, Sebastian; Silbereisen, Rainer K; Heckhausen, Jutta

2013-01-01

This paper investigates the association between perceptions of broader changes in the social-ecological context and individuals' subjective well-being (SWB). Macro-level societal changes such as globalization or demographic change give rise to new demands for individual functioning at work and/or in the family. Such new demands associated with social change are stressful and likely to be related to lower levels of SWB. Being active agents, individuals attempt to deal with social change and its increasing demands to protect their SWB. The present study investigates which kinds of control strategies are most effective in protecting one's SWB. Specifically, we predicted that control strategies of goal engagement will be most effective under conditions of perceived high control, and control strategies of goal disengagement will be most effective under conditions of perceived low control. In a large sample of 2537 German adults, work- and family-related demands associated with social change were found to be negatively linked to SWB. Moreover and in line with the motivational theory of lifespan development, control strategies of goal engagement and disengagement were beneficial for SWB to the extent that they matched the perceived control of the demands associated with social change.

Multi-Objective Sliding Mode Control on Vehicle Cornering Stability with Variable Gear Ratio Actuator-Based Active Front Steering Systems.

PubMed

Ma, Xinbo; Wong, Pak Kin; Zhao, Jing; Xie, Zhengchao

2016-12-28

Active front steering (AFS) is an emerging technology to improve the vehicle cornering stability by introducing an additional small steering angle to the driver's input. This paper proposes an AFS system with a variable gear ratio steering (VGRS) actuator which is controlled by using the sliding mode control (SMC) strategy to improve the cornering stability of vehicles. In the design of an AFS system, different sensors are considered to measure the vehicle state, and the mechanism of the AFS system is also modelled in detail. Moreover, in order to improve the cornering stability of vehicles, two dependent objectives, namely sideslip angle and yaw rate, are considered together in the design of SMC strategy. By evaluating the cornering performance, Sine with Dwell and accident avoidance tests are conducted, and the simulation results indicate that the proposed SMC strategy is capable of improving the cornering stability of vehicles in practice.

Assessing Strategies Against Gambiense Sleeping Sickness Through Mathematical Modeling

PubMed Central

Rock, Kat S; Ndeffo-Mbah, Martial L; Castaño, Soledad; Palmer, Cody; Pandey, Abhishek; Atkins, Katherine E; Ndung’u, Joseph M; Hollingsworth, T Déirdre; Galvani, Alison; Bever, Caitlin; Chitnis, Nakul; Keeling, Matt J

2018-01-01

Abstract Background Control of gambiense sleeping sickness relies predominantly on passive and active screening of people, followed by treatment. Methods Mathematical modeling explores the potential of 3 complementary interventions in high- and low-transmission settings. Results Intervention strategies that included vector control are predicted to halt transmission most quickly. Targeted active screening, with better and more focused coverage, and enhanced passive surveillance, with improved access to diagnosis and treatment, are both estimated to avert many new infections but, when used alone, are unlikely to halt transmission before 2030 in high-risk settings. Conclusions There was general model consensus in the ranking of the 3 complementary interventions studied, although with discrepancies between the quantitative predictions due to differing epidemiological assumptions within the models. While these predictions provide generic insights into improving control, the most effective strategy in any situation depends on the specific epidemiology in the region and the associated costs. PMID:29860287

Neural correlates of verbal associative memory and mnemonic strategy use following childhood traumatic brain injury

PubMed Central

Kramer, Megan E.; Chiu, C.-Y. Peter; Shear, Paula K.; Wade, Shari L.

2010-01-01

Children with traumatic brain injury (TBI) often experience memory deficits, although the nature, functional implication, and recovery trajectory of such difficulties are poorly understood. The present fMRI study examined the neural activation patterns in a group of young children who sustained moderate TBI in early childhood (n = 7), and a group of healthy control children (n = 13) during a verbal paired associate learning (PAL) task that promoted the use of two mnemonic strategies differing in efficacy. The children with TBI demonstrated intact memory performance and were able to successfully utilize the mnemonic strategies. However, the TBI group also demonstrated altered brain activation patterns during the task compared to the control children. These findings suggest early childhood TBI may alter activation within the network of brain regions supporting associative memory even in children who show good behavioral performance. PMID:21188286

Disease activity-guided dose optimisation of adalimumab and etanercept is a cost-effective strategy compared with non-tapering tight control rheumatoid arthritis care: analyses of the DRESS study.

PubMed

Kievit, Wietske; van Herwaarden, Noortje; van den Hoogen, Frank Hj; van Vollenhoven, Ronald F; Bijlsma, Johannes Wj; van den Bemt, Bart Jf; van der Maas, Aatke; den Broeder, Alfons A

2016-11-01

A disease activity-guided dose optimisation strategy of adalimumab or etanercept (TNFi (tumour necrosis factor inhibitors)) has shown to be non-inferior in maintaining disease control in patients with rheumatoid arthritis (RA) compared with usual care. However, the cost-effectiveness of this strategy is still unknown. This is a preplanned cost-effectiveness analysis of the Dose REduction Strategy of Subcutaneous TNF inhibitors (DRESS) study, a randomised controlled, open-label, non-inferiority trial performed in two Dutch rheumatology outpatient clinics. Patients with low disease activity using TNF inhibitors were included. Total healthcare costs were measured and quality adjusted life years (QALY) were based on EQ5D utility scores. Decremental cost-effectiveness analyses were performed using bootstrap analyses; incremental net monetary benefit (iNMB) was used to express cost-effectiveness. 180 patients were included, and 121 were allocated to the dose optimisation strategy and 59 to control. The dose optimisation strategy resulted in a mean cost saving of -€12 280 (95 percentile -€10 502; -€14 104) per patient per 18 months. There is an 84% chance that the dose optimisation strategy results in a QALY loss with a mean QALY loss of -0.02 (-0.07 to 0.02). The decremental cost-effectiveness ratio (DCER) was €390 493 (€5 085 184; dominant) of savings per QALY lost. The mean iNMB was €10 467 (€6553-€14 037). Sensitivity analyses using 30% and 50% lower prices for TNFi remained cost-effective. Disease activity-guided dose optimisation of TNFi results in considerable cost savings while no relevant loss of quality of life was observed. When the minimal QALY loss is compensated with the upper limit of what society is willing to pay or accept in the Netherlands, the net savings are still high. NTR3216; Post-results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Active structural control of a floating wind turbine with a stroke-limited hybrid mass damper

NASA Astrophysics Data System (ADS)

Hu, Yaqi; He, Erming

2017-12-01

Floating wind turbines are subjected to more severe structural loads than fixed-bottom wind turbines due to additional degrees of freedom (DOFs) of their floating foundations. It's a promising way of using active structural control method to improve the structural responses of floating wind turbines. This paper investigates an active vibration control strategy for a barge-type floating wind turbine by setting a stroke-limited hybrid mass damper (HMD) in the turbine's nacelle. Firstly, a contact nonlinear modeling method for the floating wind turbine with clearance between the HMD and the stroke limiters is presented based on Euler-Lagrange's equations and an active control model of the whole system is established. The structural parameters are validated for the active control model and an equivalent load coefficient method is presented for identifying the wind and wave disturbances. Then, a state-feedback linear quadratic regulator (LQR) controller is designed to reduce vibration and loads of the wind turbine, and two optimization methods are combined to optimize the weighting coefficients when considering the stroke of the HMD and the active control power consumption as constraints. Finally, the designed controllers are implemented in high fidelity simulations under five typical wind and wave conditions. The results show that active HMD control strategy is shown to be achievable and the designed controllers could further reduce more vibration and loads of the wind turbine under the constraints of stroke limitation and power consumption. "V"-shaped distribution of the TMD suppression effect is inconsistent with the Weibull distribution in practical offshore floating wind farms, and the active HMD control could overcome this shortcoming of the passive TMD.

Experimental implementation of acoustic impedance control by a 2D network of distributed smart cells

NASA Astrophysics Data System (ADS)

David, P.; Collet, M.; Cote, J.-M.

2010-03-01

New miniaturization and integration capabilities available from emerging microelectromechanical system (MEMS) technology will allow silicon-based artificial skins involving thousands of elementary actuators to be developed in the near future. Smart structures combining large arrays of elementary motion pixels are thus being studied so that fundamental properties could be dynamically adjusted. This paper investigates the acoustical capabilities of a network of distributed transducers connected with a suitable controlling strategy. The research aims at designing an integrated active interface for sound attenuation by using suitable changes of acoustical impedance. The control strategy is based on partial differential equations (PDE) and the multiscaled physics of electromechanical elements. Specific techniques based on PDE control theory have provided a simple boundary control equation able to annihilate the reflections of acoustic waves. To experimentally implement the method, the control strategy is discretized as a first order time-space operator. The obtained quasi-collocated architecture, composed of a large number of sensors and actuators, provides high robustness and stability. The experimental results demonstrate how a well controlled active skin can substantially modify sound reflectivity of the acoustical interface and reduce the propagation of acoustic waves.

Can't control yourself? Monitor those bad habits.

PubMed

Quinn, Jeffrey M; Pascoe, Anthony; Wood, Wendy; Neal, David T

2010-04-01

What strategies can people use to control unwanted habits? Past work has focused on controlling other kinds of automatic impulses, especially temptations. The nature of habit cuing calls for certain self-control strategies. Because the slow-to-change memory trace of habits is not amenable to change or reinterpretation, successful habit control involves inhibiting the unwanted response when activated in memory. In support, two episode-sampling diary studies demonstrated that bad habits, unlike responses to temptations, were controlled most effectively through spontaneous use of vigilant monitoring (thinking "don't do it," watching carefully for slipups). No other strategy was useful in controlling strong habits, despite that stimulus control was effective at inhibiting responses to temptations. A subsequent experiment showed that vigilant monitoring aids habit control, not by changing the strength of the habit memory trace but by heightening inhibitory, cognitive control processes. The implications of these findings for behavior change interventions are discussed.

Improved performance of Yarrowia lipolytica lipase-catalyzed kinetic resolution of (R,S)-2-octanol by an integrated strategy of interfacial activation, bioimprinting and immobilization.

PubMed

Liu, Ying; Guo, Chen; Sun, Xi-Tong; Liu, Chun-Zhao

2013-08-01

Yarrowia lipolytica lipase (YLL) demonstrated an (R)-enantiopreference for efficient resolution of (R,S)-2-octanol. The activity, enantioselectivity, the ratio of substrate to enzyme, acetaldehyde tolerance, and operational stability of YLL were improved by an integrated strategy of interfacial activation, bioimprinting, and immobilization. In comparison with the control, both the enzymatic activity and enantioselectivity increased by a factor of 8.85 and 2.75 by the integrated strategy, respectively. Fifty-one percentage of conversion with 220 of enantioselectivity was obtained using the immobilized YLL prepared by the integrated strategy at a ratio of 104 of substrate to enzyme loaded. The immobilized YLL retained 97% of its initial activity without a decrease in enantioselectivity after 10 successive reuse cycles. Together these results will result in a promising strategy with the YYL for efficient resolution of (R,S)-2-octanol in practice. Copyright © 2013 Elsevier Ltd. All rights reserved.

Physical activity within a CBT intervention improves coping with pain in traumatized refugees: results of a randomized controlled design.

PubMed

Liedl, Alexandra; Müller, Julia; Morina, Naser; Karl, Anke; Denke, Claudia; Knaevelsrud, Christine

2011-02-01

Many traumatized refugees experience both posttraumatic stress disorder and chronic pain. Based on Mutual Maintenance Theory and the Perpetual Avoidance Model, this study examined the additional effect of physical activity within a biofeedback-based cognitive behavioral therapy (CBT-BF) for traumatized refugees. In a controlled design, 36 patients were randomized into one of three conditions (CBT-BF, CBT-BF with physical activity [CBT-BF+active], and a waiting list control group [WL]). Thirty patients (n=10 in each group) completed the treatment and a follow-up assessment 3 months later. Participants' coping strategies, pain and mental health status, and physiological reactivity were assessed before and after the intervention and at 3-month follow-up. Treatment effects were analyzed using analyses of variance with baseline scores as covariates (ANCOVAs) and the Reliable Change Index. The CBT-BF and CBT-BF+active groups showed improvements in all outcome measures relative to the WL group. The effect sizes for the main outcome measures were higher in the CBT-BF+active group than in the CBT-BF group. Repeated measures analyses of covariance showed significant group effects for coping strategies--in particular, for the "cognitive restructuring" and "counter-activities" subscales as well as a marginally significant group effect for "perceived self-competence"--with the CBT-BF+active group showing more favorable outcomes than the CBT-BF group. Moreover, 60% of participants in the CBT-BF+active group showed clinically reliable intraindividual change in at least one subscale of the pain coping strategies questionnaire, compared with just 30% of participants in the CBT-BF group. Findings of improved coping strategies, larger effect sizes, and higher rates of clinical improvement in the CBT-BF+active group suggest that physical activity adds value to pain management interventions for traumatized refugees. Given the small sample size, however, these preliminary results need replication in a larger trial. Wiley Periodicals, Inc.

Birds achieve high robustness in uneven terrain through active control of landing conditions.

PubMed

Birn-Jeffery, Aleksandra V; Daley, Monica A

2012-06-15

We understand little about how animals adjust locomotor behaviour to negotiate uneven terrain. The mechanical demands and constraints of such behaviours likely differ from uniform terrain locomotion. Here we investigated how common pheasants negotiate visible obstacles with heights from 10 to 50% of leg length. Our goal was to determine the neuro-mechanical strategies used to achieve robust stability, and address whether strategies vary with obstacle height. We found that control of landing conditions was crucial for minimising fluctuations in stance leg loading and work in uneven terrain. Variation in touchdown leg angle (θ(TD)) was correlated with the orientation of ground force during stance, and the angle between the leg and body velocity vector at touchdown (β(TD)) was correlated with net limb work. Pheasants actively targeted obstacles to control body velocity and leg posture at touchdown to achieve nearly steady dynamics on the obstacle step. In the approach step to an obstacle, the birds produced net positive limb work to launch themselves upward. On the obstacle, body dynamics were similar to uniform terrain. Pheasants also increased swing leg retraction velocity during obstacle negotiation, which we suggest is an active strategy to minimise fluctuations in peak force and leg posture in uneven terrain. Thus, pheasants appear to achieve robustly stable locomotion through a combination of path planning using visual feedback and active adjustment of leg swing dynamics to control landing conditions. We suggest that strategies for robust stability are context specific, depending on the quality of sensory feedback available, especially visual input.

Application of the remote microphone method to active noise control in a mobile phone.

PubMed

Cheer, Jordan; Elliott, Stephen J; Oh, Eunmi; Jeong, Jonghoon

2018-04-01

Mobile phones are used in a variety of situations where environmental noise may interfere with the ability of the near-end user to communicate with the far-end user. To overcome this problem, it might be possible to use active noise control technology to reduce the noise experienced by the near-end user. This paper initially demonstrates that when an active noise control system is used in a practical mobile phone configuration to minimise the noise measured by an error microphone mounted on the mobile phone, the attenuation achieved at the user's ear depends strongly on the position of the source generating the acoustic interference. To help overcome this problem, a remote microphone processing strategy is investigated that estimates the pressure at the user's ear from the pressure measured by the microphone on the mobile phone. Through an experimental implementation, it is demonstrated that this arrangement achieves a significant improvement in the attenuation measured at the ear of the user, compared to the standard active control strategy. The robustness of the active control system to changes in both the interfering sound field and the position of the mobile device relative to the ear of the user is also investigated experimentally.

Novel mechatronic solutions incorporating inerters for railway vehicle vertical secondary suspensions

NASA Astrophysics Data System (ADS)

Matamoros-Sanchez, Alejandra Z.; Goodall, Roger M.

2015-02-01

This paper discusses the effects of inerter-based passive networks in the design of novel mechatronic solutions for improving the vertical performance of a bogied railway vehicle. Combinations of inerter-based structures and active suspensions comprise distinct novel mechatronic solutions for the vertical secondary suspension of the vehicle. The parameters of the active and passive parts of the overall configuration are optimised so that a synergy arises to enhance the vehicle vertical performance and simplify common mechatronic suspension design conflicts. The study is performed by combining inerter-based suspensions with well-established active control (output-based and model-based) strategies for ride quality enhancement. Also, a novel nonlinear control strategy, here called 'Adaptive Stiffness', is incorporated for suspension deflection regulation to complement the well-known local implementation of skyhook damping. This would complete a significant set of control strategies to produce general conclusions. The vehicle performance is assessed through the vertical accelerations of the vehicle body as an initial investigation. Attained results show the potential of the inerter concept for innovating mechatronic technologies to achieve substantial improvements in railway vehicle vertical ride quality with reduced actuator force.

The effect of active learning on college students' achievement, motivation, and self-efficacy in a human physiology course for non-majors

NASA Astrophysics Data System (ADS)

Wilke, Roger Russell

2000-10-01

This study investigated the effects active learning strategies had on college students' achievement, motivation, and self-efficacy, in a human physiology course for non-majors. A continuum-based active learning instructional model was implemented over the course of a semester to assess the effects on the variables and specific student outcomes of learning mentioned above. In addition analyses were conducted to explore what learner characteristics contributed to the successful implementation of the model such as students' gender, classification, major, grade point average, ACT and SAT scores, motivation, and self-efficacy. A quasi-experimental, Solomon-4 Group design was undertaken on 171 students in a small west-Texas university. Treatment groups were taught using the model while controls were taught using traditional lecture methods. Students were administered a comprehensive physiology content exam, sections of the Motivated Strategies for Learning Questionnaire, and attitude surveys to assess the effects of the continuum-based active learning strategies. Factorial analyses indicated the treatment group acquired significantly more content knowledge and were significantly more self-efficacious than students in the control group. There were no significant differences in motivation. Factorial and modified regression analyses in the aptitude by treatment interaction exploration determined that males in the treatment group performed significantly better on the comprehensive physiology content exam versus males in the control group. While females performed better overall than males, there were no significant differences in achievement between females in the treatment group and those in the control. No significant interactions were found for the other learner characteristics. The results also indicated that students' general cognitive ability as measured by their grade point average, ACT, and SAT scores and their self-efficacy contributed significantly to their achievement. Attitude surveys indicated that students in both the treatment and control groups demonstrated a positive attitude toward active learning, believed it helped them to learn the material, and would choose an active learning course in the future if given the opportunity. This study demonstrated that continuum-based active learning strategies used in this context, improved students' content acquisition and self-efficacy and had wide applicability with a number of learner characteristics.

Poor decision-making by chronic marijuana users is associated with decreased functional responsiveness to negative consequences.

PubMed

Wesley, Michael J; Hanlon, Colleen A; Porrino, Linda J

2011-01-30

Chronic marijuana users (MJ Users) perform poorly on the Iowa Gambling Task (IGT), a complex decision-making task in which monetary wins and losses guide strategy development. This functional magnetic resonance imaging (MRI) study sought to determine if the poor performance of MJ Users was related to differences in brain activity while evaluating wins and losses during the strategy development phase of the IGT. MJ Users (16) and Controls (16) performed a modified IGT in an MRI scanner. Performance was tracked and functional activity in response to early wins and losses was examined. While the MJ Users continued to perform poorly at the end of the task, there was no difference in group performance during the initial strategy development phase. During this phase, before the emergence of behavioral differences, Controls exhibited significantly greater activity in response to losses in the anterior cingulate cortex, medial frontal cortex, precuneus, superior parietal lobe, occipital lobe and cerebellum as compared to MJ Users. Furthermore, in Controls, but not MJ Users, the functional response to losses in the anterior cingulate cortex, ventral medial prefrontal cortex and rostral prefrontal cortex positively correlated with performance over time. These data suggest MJ Users are less sensitive to negative feedback during strategy development. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Benchmark Simulation Model No 2: finalisation of plant layout and default control strategy.

PubMed

Nopens, I; Benedetti, L; Jeppsson, U; Pons, M-N; Alex, J; Copp, J B; Gernaey, K V; Rosen, C; Steyer, J-P; Vanrolleghem, P A

2010-01-01

The COST/IWA Benchmark Simulation Model No 1 (BSM1) has been available for almost a decade. Its primary purpose has been to create a platform for control strategy benchmarking of activated sludge processes. The fact that the research work related to the benchmark simulation models has resulted in more than 300 publications worldwide demonstrates the interest in and need of such tools within the research community. Recent efforts within the IWA Task Group on "Benchmarking of control strategies for WWTPs" have focused on an extension of the benchmark simulation model. This extension aims at facilitating control strategy development and performance evaluation at a plant-wide level and, consequently, includes both pretreatment of wastewater as well as the processes describing sludge treatment. The motivation for the extension is the increasing interest and need to operate and control wastewater treatment systems not only at an individual process level but also on a plant-wide basis. To facilitate the changes, the evaluation period has been extended to one year. A prolonged evaluation period allows for long-term control strategies to be assessed and enables the use of control handles that cannot be evaluated in a realistic fashion in the one week BSM1 evaluation period. In this paper, the finalised plant layout is summarised and, as was done for BSM1, a default control strategy is proposed. A demonstration of how BSM2 can be used to evaluate control strategies is also given.

The effect of encoding strategy on the neural correlates of memory for faces.

PubMed

Bernstein, Lori J; Beig, Sania; Siegenthaler, Amy L; Grady, Cheryl L

2002-01-01

Encoding and recognition of unfamiliar faces in young adults were examined using positron emission tomography to determine whether different encoding strategies would lead to encoding/retrieval differences in brain activity. Three types of encoding were compared: a 'deep' task (judging pleasantness/unpleasantness), a 'shallow' task (judging right/left orientation), and an intentional learning task in which subjects were instructed to learn the faces for a subsequent memory test but were not provided with a specific strategy. Memory for all faces was tested with an old/new recognition test. A modest behavioral effect was obtained, with deeply-encoded faces being recognized more accurately than shallowly-encoded or intentionally-learned faces. Regardless of encoding strategy, encoding activated a primarily ventral system including bilateral temporal and fusiform regions and left prefrontal cortices, whereas recognition activated a primarily dorsal set of regions including right prefrontal and parietal areas. Within encoding, the type of strategy produced different brain activity patterns, with deep encoding being characterized by left amygdala and left anterior cingulate activation. There was no effect of encoding strategy on brain activity during the recognition conditions. Posterior fusiform gyrus activation was related to better recognition accuracy in those conditions encouraging perceptual strategies, whereas activity in left frontal and temporal areas correlated with better performance during the 'deep' condition. Results highlight three important aspects of face memory: (1) the effect of encoding strategy was seen only at encoding and not at recognition; (2) left inferior prefrontal cortex was engaged during encoding of faces regardless of strategy; and (3) differential activity in fusiform gyrus was found, suggesting that activity in this area is not only a result of automatic face processing but is modulated by controlled processes.

Graphene-polymer hybrid nanostructure-based bioenergy storage device for real-time control of biological motor activity.

PubMed

Byun, Kyung-Eun; Choi, Dong Shin; Kim, Eunji; Seo, David H; Yang, Heejun; Seo, Sunae; Hong, Seunghun

2011-11-22

We report a graphene-polymer hybrid nanostructure-based bioenergy storage device to turn on and off biomotor activity in real-time. In this strategy, graphene was functionalized with amine groups and utilized as a transparent electrode supporting the motility of biomotors. Conducting polymer patterns doped with adenosine triphosphate (ATP) were fabricated on the graphene and utilized for the fast release of ATP by electrical stimuli through the graphene. The controlled release of biomotor fuel, ATP, allowed us to control the actin filament transportation propelled by the biomotor in real-time. This strategy should enable the integrated nanodevices for the real-time control of biological motors, which can be a significant stepping stone toward hybrid nanomechanical systems based on motor proteins. © 2011 American Chemical Society

A novel optimal coordinated control strategy for the updated robot system for single port surgery.

PubMed

Bai, Weibang; Cao, Qixin; Leng, Chuntao; Cao, Yang; Fujie, Masakatsu G; Pan, Tiewen

2017-09-01

Research into robotic systems for single port surgery (SPS) has become widespread around the world in recent years. A new robot arm system for SPS was developed, but its positioning platform and other hardware components were not efficient. Special features of the developed surgical robot system make good teleoperation with safety and efficiency difficult. A robot arm is combined and used as new positioning platform, and the remote center motion is realized by a new method using active motion control. A new mapping strategy based on kinematics computation and a novel optimal coordinated control strategy based on real-time approaching to a defined anthropopathic criterion configuration that is referred to the customary ease state of human arms and especially the configuration of boxers' habitual preparation posture are developed. The hardware components, control architecture, control system, and mapping strategy of the robotic system has been updated. A novel optimal coordinated control strategy is proposed and tested. The new robot system can be more dexterous, intelligent, convenient and safer for preoperative positioning and intraoperative adjustment. The mapping strategy can achieve good following and representation for the slave manipulator arms. And the proposed novel control strategy can enable them to complete tasks with higher maneuverability, lower possibility of self-interference and singularity free while teleoperating. Copyright © 2017 John Wiley & Sons, Ltd.

The influence of parametric and external noise in act-and-wait control with delayed feedback.

PubMed

Wang, Jiaxing; Kuske, Rachel

2017-11-01

We apply several novel semi-analytic approaches for characterizing and calculating the effects of noise in a system with act-and-wait control. For concrete illustration, we apply these to a canonical balance model for an inverted pendulum to study the combined effect of delay and noise within the act-and-wait setting. While the act-and-wait control facilitates strong stabilization through deadbeat control, a comparison of different models with continuous vs. discrete updating of the control strategy in the active period illustrates how delays combined with the imprecise application of the control can seriously degrade the performance. We give several novel analyses of a generalized act-and-wait control strategy, allowing flexibility in the updating of the control strategy, in order to understand the sensitivities to delays and random fluctuations. In both the deterministic and stochastic settings, we give analytical and semi-analytical results that characterize and quantify the dynamics of the system. These results include the size and shape of stability regions, densities for the critical eigenvalues that capture the rate of reaching the desired stable equilibrium, and amplification factors for sustained fluctuations in the context of external noise. They also provide the dependence of these quantities on the length of the delay and the active period. In particular, we see that the combined influence of delay, parametric error, or external noise and on-off control can qualitatively change the dynamics, thus reducing the robustness of the control strategy. We also capture the dependence on how frequently the control is updated, allowing an interpolation between continuous and frequent updating. In addition to providing insights for these specific models, the methods we propose are generalizable to other settings with noise, delay, and on-off control, where analytical techniques are otherwise severely scarce.

Active Control of Mixing and Combustion, from Mechanisms to Implementation

NASA Astrophysics Data System (ADS)

Ghoniem, Ahmed F.

2001-11-01

Implementation of active control in complex processes, of the type encountered in high Reynolds number mixing and combustion, is predicated upon the identification of the underlying mechanisms and the construction of reduced order models that capture their essential characteristics. The mechanisms of interest must be shown to be amenable to external actuations, allowing optimal control strategies to exploit the delicate interactions that lead to the desired outcome. Reduced order models are utilized in defining the form and requisite attributes of actuation, its relationship to the monitoring system and the relevant control algorithms embedded in a feedforward or a feedback loop. The talk will review recent work on active control of mixing in combustion devices in which strong shear zones concur with mixing, combustion stabilization and flame anchoring. The underlying mechanisms, e.g., stability of shear flows, formation/evolution of large vortical structures in separating and swirling flows, their mutual interactions with acoustic fields, flame fronts and chemical kinetics, etc., are discussed in light of their key roles in mixing, burning enhancement/suppression, and combustion instability. Subtle attributes of combustion mechanisms are used to suggest the requisite control strategies.

Effects of Plyometric Training on Muscle-Activation Strategies and Performance in Female Athletes

PubMed Central

Swanik, Kathleen A.; Swanik, C. Buz; Straub, Stephen J.

2004-01-01

Objective: To evaluate the effects of plyometric training on muscle-activation strategies and performance of the lower extremity during jumping exercises. Subjects: Twenty healthy National Collegiate Athletic Association Division I female athletes. Design and Setting: A pretest and posttest control group design was used. Experimental subjects performed plyometric exercises 2 times per week for 6 weeks. Measurements: We used surface electromyography to assess preparatory and reactive activity of the vastus medialis and vastus lateralis, medial and lateral hamstrings, and hip abductors and adductors. Vertical jump height and sprint speed were assessed with the VERTEC and infrared timing devices, respectively. Results: Multivariate analyses of variance revealed significant (P < .05) increases in firing of adductor muscles during the preparatory phase, with significant interactions for area, mean, and peak. A Tukey honestly significant difference post hoc analysis revealed significant increases in preparatory adductor area, mean, and peak for experimental group. A significant (P = .037) increase in preparatory adductor-to-abductor muscle coactivation in the experimental group was identified, as well as a trend (P = .053) toward reactive quadriceps-to- hamstring muscle coactivation in the experimental group. Pearson correlation coefficients revealed significant between-groups adaptations in muscle activity patterns pretest to posttest. Although not significant, experimental and control subjects had average increases of 5.8% and 2.0% in vertical jump height, respectively. Conclusions: The increased preparatory adductor activity and abductor-to-adductor coactivation represent preprogrammed motor strategies learned during the plyometric training. These data strongly support the role of hip-musculature activation strategies for dynamic restraint and control of lower extremity alignment at ground contact. Plyometric exercises should be incorporated into the training regimens of female athletes and may reduce the risk of injury by enhancing functional joint stability in the lower extremity. PMID:15085208

Neural substrates of similarity and rule-based strategies in judgment

PubMed Central

von Helversen, Bettina; Karlsson, Linnea; Rasch, Björn; Rieskamp, Jörg

2014-01-01

Making accurate judgments is a core human competence and a prerequisite for success in many areas of life. Plenty of evidence exists that people can employ different judgment strategies to solve identical judgment problems. In categorization, it has been demonstrated that similarity-based and rule-based strategies are associated with activity in different brain regions. Building on this research, the present work tests whether solving two identical judgment problems recruits different neural substrates depending on people's judgment strategies. Combining cognitive modeling of judgment strategies at the behavioral level with functional magnetic resonance imaging (fMRI), we compare brain activity when using two archetypal judgment strategies: a similarity-based exemplar strategy and a rule-based heuristic strategy. Using an exemplar-based strategy should recruit areas involved in long-term memory processes to a larger extent than a heuristic strategy. In contrast, using a heuristic strategy should recruit areas involved in the application of rules to a larger extent than an exemplar-based strategy. Largely consistent with our hypotheses, we found that using an exemplar-based strategy led to relatively higher BOLD activity in the anterior prefrontal and inferior parietal cortex, presumably related to retrieval and selective attention processes. In contrast, using a heuristic strategy led to relatively higher activity in areas in the dorsolateral prefrontal and the temporal-parietal cortex associated with cognitive control and information integration. Thus, even when people solve identical judgment problems, different neural substrates can be recruited depending on the judgment strategy involved. PMID:25360099

Control strategies for planetary rover motion and manipulator control

NASA Technical Reports Server (NTRS)

Trautwein, W.

1973-01-01

An unusual insect-like vehicle designed for planetary surface exploration is made the occasion for a discussion of control concepts in path selection, hazard detection, obstacle negotiation, and soil sampling. A control scheme which actively articulates the pitching motion between a single-loop front module and a dual loop rear module leads to near optimal behavior in soft soil; at the same time the vehicle's front module acts as a reliable tactile forward probe with a detection range much longer than the stopping distance. Some optimal control strategies are discussed, and the photos of a working scale model are displayed.

Research Priorities for FCTC Articles 20, 21, and 22: Surveillance/Evaluation and Information Exchange

PubMed Central

2013-01-01

Introduction: Framework Convention on Tobacco Control (FCTC) Articles 20, 21, and 22 call for strong monitoring and reporting of tobacco use and factors influencing use and disease (Articles 20 and 21) and for collaboration among the Parties and relevant organizations to share resources, knowledge, and expertise on all relevant tobacco control strategies (Article 22). Methods: This paper provides background information and discusses research strategies that would strengthen these efforts and better inform the Parties. By necessity, Articles 20 and 21 are discussed separately from Article 22, although 1 example that relates to both 20/21 and 22 is discussed at the end. Results: Twelve important research opportunities on surveillance and evaluation are recognized, along with 4 on collaboration. The authors believe that the 6 most important areas for research would study (a) possible underreporting of tobacco use among certain demographic groups in some countries, (b) measures of industry activities, (c) optimal sampling strategies, (d) sentinel surveillance, (e) networks of tobacco companies and their partners as they promote tobacco use and interfere with implementation of the FCTC, and (f) network/relationship factors that impact diffusion of knowledge and decision making on the implementation of the FCTC. In addition, we call for a review process of existing surveillance and evaluation strategies to coordinate activities to make optimal use of existing resources. This activity would involve networking as prescribed in Article 22. Conclusions: Studies and activities such as these would facilitate control of the tobacco epidemic. PMID:23335488

Research priorities for FCTC Articles 20, 21, and 22: surveillance/evaluation and information exchange.

PubMed

Giovino, Gary A; Kulak, Jessica A; Kalsbeek, William D; Leischow, Scott J

2013-04-01

Framework Convention on Tobacco Control (FCTC) Articles 20, 21, and 22 call for strong monitoring and reporting of tobacco use and factors influencing use and disease (Articles 20 and 21) and for collaboration among the Parties and relevant organizations to share resources, knowledge, and expertise on all relevant tobacco control strategies (Article 22). This paper provides background information and discusses research strategies that would strengthen these efforts and better inform the parties. By necessity, Articles 20 and 21 are discussed separately from Article 22, although 1 example that relates to both 20/21 and 22 is discussed at the end. Twelve important research opportunities on surveillance and evaluation are recognized, along with 4 on collaboration. The authors believe that the 6 most important areas for research would study (a) possible underreporting of tobacco use among certain demographic groups in some countries, (b) measures of industry activities, (c) optimal sampling strategies, (d) sentinel surveillance, (e) networks of tobacco companies and their partners as they promote tobacco use and interfere with implementation of the FCTC, and (f) network/relationship factors that impact diffusion of knowledge and decision making on the implementation of the FCTC. In addition, we call for a review process of existing surveillance and evaluation strategies to coordinate activities to make optimal use of existing resources. This activity would involve networking as prescribed in Article 22. Studies and activities such as these would facilitate control of the tobacco epidemic.

Controlling the Active Sites of Sulfur-Doped Carbon Nanotube-Graphene Nanolobes for Highly Efficient Oxygen Evolution and Reduction Catalysis

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

El-Sawy, Abdelhamid M.; Mosa, Islam M.; Su, Dong

Controlling active sites of metal-free catalysts is an important strategy to enhance activity of the oxygen evolution reaction (OER). We made many attempts have been made to develop metal-free catalysts, but the lack of understanding of active-sites at the atomic-level has slowed the design of highly active and stable metal-free catalysts. We also developed a sequential two-step strategy to dope sulfur into carbon nanotube–graphene nanolobes. This bidoping strategy introduces stable sulfur–carbon active-sites. Fluorescence emission of the sulfur K-edge by X-ray absorption near edge spectroscopy (XANES) and scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) mapping and spectra confirm thatmore » increasing the incorporation of heterocyclic sulfur into the carbon ring of CNTs not only enhances OER activity with an overpotential of 350 mV at a current density of 10 mA cm -2, but also retains 100% of stability after 75 h. Furthermore, the bidoped sulfur carbon nanotube–graphene nanolobes behave like the state-of-the-art catalysts for OER but outperform those systems in terms of turnover frequency (TOF) which is two orders of magnitude greater than (20% Ir/C) at 400 mV overpotential with very high mass activity 1000 mA cm -2 at 570 mV. Moreover, the sulfur bidoping strategy shows high catalytic activity for the oxygen reduction reaction (ORR). Stable bifunctional (ORR and OER) catalysts are low cost, and light-weight bidoped sulfur carbon nanotubes are potential candidates for next-generation metal-free regenerative fuel cells.« less

Controlling the Active Sites of Sulfur-Doped Carbon Nanotube-Graphene Nanolobes for Highly Efficient Oxygen Evolution and Reduction Catalysis

DOE PAGES

El-Sawy, Abdelhamid M.; Mosa, Islam M.; Su, Dong; ...

2015-12-03

Controlling active sites of metal-free catalysts is an important strategy to enhance activity of the oxygen evolution reaction (OER). We made many attempts have been made to develop metal-free catalysts, but the lack of understanding of active-sites at the atomic-level has slowed the design of highly active and stable metal-free catalysts. We also developed a sequential two-step strategy to dope sulfur into carbon nanotube–graphene nanolobes. This bidoping strategy introduces stable sulfur–carbon active-sites. Fluorescence emission of the sulfur K-edge by X-ray absorption near edge spectroscopy (XANES) and scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) mapping and spectra confirm thatmore » increasing the incorporation of heterocyclic sulfur into the carbon ring of CNTs not only enhances OER activity with an overpotential of 350 mV at a current density of 10 mA cm -2, but also retains 100% of stability after 75 h. Furthermore, the bidoped sulfur carbon nanotube–graphene nanolobes behave like the state-of-the-art catalysts for OER but outperform those systems in terms of turnover frequency (TOF) which is two orders of magnitude greater than (20% Ir/C) at 400 mV overpotential with very high mass activity 1000 mA cm -2 at 570 mV. Moreover, the sulfur bidoping strategy shows high catalytic activity for the oxygen reduction reaction (ORR). Stable bifunctional (ORR and OER) catalysts are low cost, and light-weight bidoped sulfur carbon nanotubes are potential candidates for next-generation metal-free regenerative fuel cells.« less

Effectiveness and practicality of control strategies for African swine fever: what do we really know?

PubMed Central

Guinat, C.; Vergne, T.; Jurado-Diaz, C.; Sánchez-Vizcaíno, J. M.; Dixon, L.; Pfeiffer, D. U.

2017-01-01

African swine fever (ASF) is a major pig health problem, and the causative virus is moving closer to Western European regions where pig density is high. Stopping or slowing down the spread of ASF requires mitigation strategies that are both effective and practical. Based on the elicitation of ASF expert opinion, this study identified surveillance and intervention strategies for ASF that are perceived as the most effective by providing the best combination between effectiveness and practicality. Among the 20 surveillance strategies that were identified, passive surveillance of wild boar and syndromic surveillance of pig mortality were considered to be the most effective surveillance strategies for controlling ASF virus spread. Among the 22 intervention strategies that were identified, culling of all infected herds and movement bans for neighbouring herds were regarded as the most effective intervention strategies. Active surveillance and carcase removal in wild boar populations were rated as the most effective surveillance and intervention strategies, but were also considered to be the least practical, suggesting that more research is needed to develop more effective methods for controlling ASF in wild boar populations. PMID:27852963

Horizontal infection control strategy decreases methicillin-resistant Staphylococcus aureus infection and eliminates bacteremia in a surgical ICU without active surveillance.

PubMed

Traa, Maria X; Barboza, Lorena; Doron, Shira; Snydman, David R; Noubary, Farzad; Nasraway, Stanley A

2014-10-01

Methicillin-resistant Staphylococcus aureus infection is a significant contributor to morbidity and mortality in hospitalized patients worldwide. Numerous healthcare bodies in Europe and the United States have championed active surveillance per the "search and destroy" model. However, this strategy is associated with significant economic, logistical, and patient costs without any impact on other hospital-acquired pathogens. We evaluated whether horizontal infection control strategies could decrease the prevalence of methicillin-resistant S. aureus infection in the ICU, without the need for active surveillance. Retrospective, observational study in the surgical ICU of a tertiary care medical center in Boston, MA, from 2005 to 2012. A total of 6,697 patients in the surgical ICU. Evidence-based infection prevention strategies were implemented in an iterative fashion, including 1) hand hygiene program with refresher education campaign, 2) chlorhexidine oral hygiene program, 3) chlorhexidine bathing, 4) catheter-associated bloodstream infection program, and 5) daily goals sheets. The prevalence of methicillin-resistant S. aureus infection fell from 2.66 to 0.69 per 1,000 patient days from 2005 to 2012, an average decrease of 21% per year. The biggest decline in rate of infection was detected in 2008, which may suggest that the catheter-associated bloodstream infection prevention program was particularly effective. Among 4,478 surgical ICU admissions over the last 5 years, not a single case of methicillin-resistant S. aureus bacteremia was observed. Aggressive multifaceted horizontal infection control is an effective strategy for reducing the prevalence of methicillin-resistant S. aureus infection and eliminating methicillin-resistant S. aureus bacteremia in the ICU without the need for active surveillance and decontamination.

Control strategies and noncompliance in abusive mother-child dyads: an observational study.

PubMed

Oldershaw, L; Walters, G C; Hall, D K

1986-06-01

The present observational study of child abuse has isolated parental control strategies and child response as a promising area of investigation. The social interaction of 10 abusive and 10 matched control mothers and their preschool children was videotaped in a simulated home environment involving both structured and unstructured activities. A coding scheme was developed to record interactional behavior in each dyad. Particular emphasis was placed on the analysis of mother command/child compliance sequences. Compared to controls, abusive mothers employed more commands, and more power-assertive and less positively oriented control strategies. They were also more intrusive, more inconsistent in their use of parenting techniques, displayed more flattened affect throughout their control interactions, and were less flexible in their attempts to gain compliance from the child. In turn, children of abusive mothers demonstrated far more noncompliant behavior than their control counterparts.

The influence of encoding strategy on episodic memory and cortical activity in schizophrenia.

PubMed

Bonner-Jackson, Aaron; Haut, Kristen; Csernansky, John G; Barch, Deanna M

2005-07-01

Recent work suggests that episodic memory deficits in schizophrenia may be related to disturbances of encoding or retrieval. Schizophrenia patients appear to benefit from instruction in episodic memory strategies. We tested the hypothesis that providing effective encoding strategies to schizophrenia patients enhances encoding-related brain activity and recognition performance. Seventeen schizophrenia patients and 26 healthy comparison subjects underwent functional magnetic resonance imaging scans while performing incidental encoding tasks of words and faces. Subjects were required to make either deep (abstract/concrete) or shallow (alphabetization) judgments for words and deep (gender) judgments for faces, followed by subsequent recognition tests. Schizophrenia and comparison subjects recognized significantly more words encoded deeply than shallowly, activated regions in inferior frontal cortex (Brodmann area 45/47) typically associated with deep and successful encoding of words, and showed greater left frontal activation for the processing of words compared with faces. However, during deep encoding and material-specific processing (words vs. faces), participants with schizophrenia activated regions not activated by control subjects, including several in prefrontal cortex. Our findings suggest that a deficit in use of effective strategies influences episodic memory performance in schizophrenia and that abnormalities in functional brain activation persist even when such strategies are applied.

What is the role of health education in the integrated strategy to control transmission of Schistosoma japonicum in China?

PubMed

Liu, Rong; Dong, Hui-Fen; Jiang, Ming-Sen

2012-05-01

In 2009, Wang et al.'s field trial published in the New England Journal of Medicine, reported that a comprehensive strategy aiming to reduce the roles of humans and cattle as sources of Schistosoma japonicum infection in snails was implemented and proved effective and promising in dramatically reducing the percentage of infected humans and snails, which had been extended to other endemic provinces in China afterwards. This implies that the integrated schistosomiasis-control strategies of interventions including political will, financial support and residents' participation to control human and bovine sources of S. japonicum infection in snails may direct to successfully interrupt the parasitic transmission and to ultimately eliminate schistosomiasis. Confusingly, however, the role of health education, which is a critical part of the integrated strategy and should play an active role in schistosomiasis control, was not reflected. We wish the authors to provide the readers a better and clearer statement of the role of health education as part of the integrated control strategy and so we write this comment.

Mindfulness as a strategy for coping with cue-elicited cravings for alcohol: an experimental examination.

PubMed

Murphy, Cara M; MacKillop, James

2014-04-01

Mindfulness has been identified as a promising strategy for managing cravings for alcohol and other drugs, but little controlled experimental research has directly studied whether this approach is effective. The current study systematically examined the effects of an acute mindfulness manipulation on craving for alcohol during prolonged exposure to alcohol cues. Heavy drinkers (N = 84, 50% male) underwent a prolonged alcohol cue exposure paradigm in a simulated bar environment and received either a mindfulness-based strategy, a distraction (DST)-based strategy (active control), or no strategy (passive control) to cope with alcohol cravings and discomfort associated with craving. No baseline differences were present between conditions. Manipulation checks revealed that participants in the 2 active conditions reported using the recommended strategies. Across groups, the initial exposure to alcohol cues was associated with significant increases in craving, urge distress, and heart rate. Mixed analyses of variance on these indices following the experimental manipulation revealed significant differences based on condition over the course of the bar laboratory protocol. The DST strategy was significantly more effective at acutely reducing craving and urge distress than the other 2 conditions, which did not significantly differ from each other. Contrary to our prediction, these findings suggest that an acute DSTstrategy is beneficial for coping with alcohol cravings. The potential importance of protracted mindfulness training to detect significant effects on in vivo craving, additional implications, and methodological considerations are discussed. Copyright © 2013 by the Research Society on Alcoholism.

The nature of mind wandering during reading varies with the cognitive control demands of the reading strategy.

PubMed

Moss, Jarrod; Schunn, Christian D; Schneider, Walter; McNamara, Danielle S

2013-11-20

Prior studies of mind wandering find the default network active during mind wandering, but these studies have yielded mixed results concerning the role of cognitive control brain regions during mind wandering. Mind wandering often interferes with reading comprehension, and prior neuroimaging studies of discourse comprehension and strategic reading comprehension have shown that there are at least two networks of brain regions that support strategic discourse comprehension: a domain-general control network and a network of regions supporting coherence-building comprehension processes. The present study was designed to further examine the neural correlates of mind wandering by examining mind wandering during strategic reading comprehension. Participants provided ratings of mind wandering frequency that were used to investigate interactions between the strategy being performed and brain regions whose activation was modulated by wind wandering. The results support prior findings showing that cognitive control regions are at times more active during mind wandering than during a task with low control demands, such as rereading. This result provides an initial examination of the neural correlates of mind wandering during discourse comprehension and shows that the processes being engaged by the primary task need to be considered when studying mind wandering. The results also replicate, in a different learning domain, prior findings of key brain areas associated with different reading strategies. © 2013 Published by Elsevier B.V.

The effect of speed-accuracy strategy on response interference control in Parkinson's disease.

PubMed

Wylie, S A; van den Wildenberg, W P M; Ridderinkhof, K R; Bashore, T R; Powell, V D; Manning, C A; Wooten, G F

2009-07-01

Studies that used conflict paradigms such as the Eriksen Flanker task show that many individuals with Parkinson's disease (PD) have pronounced difficulty resolving the conflict that arises from the simultaneous activation of mutually exclusive responses. This finding fits well with contemporary views that postulate a key role for the basal ganglia in action selection. The present experiment aims to specify the cognitive processes that underlie action selection deficits among PD patients in the context of variations in speed-accuracy strategy. PD patients (n=28) and healthy controls (n=17) performed an arrow version of the flanker task under task instructions that either emphasized speed or accuracy of responses. Reaction time (RT) and accuracy rates decreased with speed compared to accuracy instructions, although to a lesser extent for the PD group. Differences in flanker interference effects among PD and healthy controls depended on speed-accuracy strategy. Compared to the healthy controls, PD patients showed larger flanker interference effects under speed stress. RT distribution analyses suggested that PD patients have greater difficulty suppressing incorrect response activation when pressing for speed. These initial findings point to an important interaction between strategic and computational aspects of interference control in accounting for cognitive impairments of PD. The results are also compatible with recent brain imaging studies that demonstrate basal ganglia activity to co-vary with speed-accuracy adjustments.

Adaptive Optics Facility: control strategy and first on-sky results of the acquisition sequence

NASA Astrophysics Data System (ADS)

Madec, P.-Y.; Kolb, J.; Oberti, S.; Paufique, J.; La Penna, P.; Hackenberg, W.; Kuntschner, H.; Argomedo, J.; Kiekebusch, M.; Donaldson, R.; Suarez, M.; Arsenault, R.

2016-07-01

The Adaptive Optics Facility is an ESO project aiming at converting Yepun, one of the four 8m telescopes in Paranal, into an adaptive telescope. This is done by replacing the current conventional secondary mirror of Yepun by a Deformable Secondary Mirror (DSM) and attaching four Laser Guide Star (LGS) Units to its centerpiece. In the meantime, two Adaptive Optics (AO) modules have been developed incorporating each four LGS WaveFront Sensors (WFS) and one tip-tilt sensor used to control the DSM at 1 kHz frame rate. The four LGS Units and one AO module (GRAAL) have already been assembled on Yepun. Besides the technological challenge itself, one critical area of AOF is the AO control strategy and its link with the telescope control, including Active Optics used to shape M1. Another challenge is the request to minimize the overhead due to AOF during the acquisition phase of the observation. This paper presents the control strategy of the AOF. The current control of the telescope is first recalled, and then the way the AO control makes the link with the Active Optics is detailed. Lab results are used to illustrate the expected performance. Finally, the overall AOF acquisition sequence is presented as well as first results obtained on sky with GRAAL.

Trunk muscle activation patterns during walking among persons with lower limb loss: Influences of walking speed.

PubMed

Butowicz, Courtney M; Acasio, Julian C; Dearth, Christopher L; Hendershot, Brad D

2018-03-26

Persons with lower limb amputation (LLA) walk with altered trunk-pelvic motions. The underlying trunk muscle activation patterns associated with these motions may provide insight into neuromuscular control strategies post LLA and the increased incidence of low back pain (LBP). Eight males with unilateral LLA and ten able-bodied controls (CTR) walked over ground at 1.0 m/s, 1.3 m/s, 1.6 m/s, and self-selected speeds. Trunk muscle onsets/offsets were determined from electromyographic activity of bilateral thoracic (TES) and lumbar (LES) erector spinae. Trunk-pelvic kinematics were simultaneously recorded. There were no differences in TES onset times between groups; however, LLA demonstrated a second TES onset during mid-to-terminal swing (not seen in CTR), and activation for a larger percentage of the gait cycle. LLA (vs. CTR) demonstrated an earlier onset of LES and activation for a larger percentage of the gait cycle at most speeds. LLA walked with increased frontal plane trunk ROM, and a more in-phase inter-segmental coordination at all speeds. These data collectively suggest that trunk neuromuscular control strategies secondary to LLA are driven by functional needs to generate torque proximally to advance the affected limb during gait, though this strategy may have unintended deleterious consequences such as increasing LBP risk over time. Published by Elsevier Ltd.

Interactions between neurons in the frontal cortex and hippocampus in cats trained to select reinforcements of different value in conditions of cholinergic deficiency.

PubMed

Dolbakyan, E E; Merzhanova, G Kh

2007-09-01

An operant food-related conditioned reflex was developed in six cats by the "active choice" protocol: short-latency pedal presses were followed by presentation of low-quality reinforcement (bread-meat mix), while long-latency pedal presses were followed by presentation of high-quality reinforcement (meat). Animals differed in terms of their food-procuring strategies, displaying "self-control," "ambivalence," or "impulsivity." Multineuron activity was recorded from the frontal cortex and hippocampus (field CA3). Cross-correlation analysis of interneuronal interactions within (local networks) and between (distributed networks) study structures showed that the numbers of interneuronal interactions in both local and distributed networks were maximal in animals with "self-control." On the background of systemic administration of the muscarinic cholinoreceptor blockers scopolamine and trihexyphenidyl, the numbers of interneuronal interactions decreased, while "common source" influences increased. This correlated with impairment of the reproduction of the selected strategy, primarily affecting the animals' self-controlled behavior. These results show that the "self-control" strategy is determined by the organization of local and distributed networks in the frontal cortex and hippocampus.

Lifestyle of patients with diabetes mellitus type 1: a systematic review.

PubMed

Sales-Peres, Silvia Helena de Carvalho; Guedes, Maria de Fatima Santos; Sá, Letícia Marques; Negrato, Carlos Antonio; Lauris, José Roberto Pereira

2016-04-01

The aim of this review was to verify data concerning the relationship between the existent lifestyle and glycemic control in patients with Diabetes Mellitus Type 1 (DM1). The methods applied included the literature search strategy, selection of studies by means of inclusion and exclusion strategies, according to the characteristics of the studies. The search was conducted in the Lilacs, Medline, PubMed, Cochrame, SciELO and IBECS databases between in the period between 2005 and 2014. The articles selected were studies in humans, investing lifestyle, physical activities and glycemic levels. Of the 1798 studies initially identified, 11 met the eligibility criteria. Among the studies analyzed, 1 cohort; 1 longitudinal prospective, 1 case control and 8 transversal studies that approached the proposed theme were related. Regular physical activity was the variable that presented greatest relationship with the improvement in glycemic levels. Healthy active life, balanced diet, physical activities and education in diabetes improved the glycemic control of the DM1 patient. The results allowed the authors to conclude that a lifestyle based on physical activities interfered directly in the health of patients with DM1, in addition to contributing the glycemic control.

Closed-loop control of epileptiform activities in a neural population model using a proportional-derivative controller

NASA Astrophysics Data System (ADS)

Wang, Jun-Song; Wang, Mei-Li; Li, Xiao-Li; Ernst, Niebur

2015-03-01

Epilepsy is believed to be caused by a lack of balance between excitation and inhibitation in the brain. A promising strategy for the control of the disease is closed-loop brain stimulation. How to determine the stimulation control parameters for effective and safe treatment protocols remains, however, an unsolved question. To constrain the complex dynamics of the biological brain, we use a neural population model (NPM). We propose that a proportional-derivative (PD) type closed-loop control can successfully suppress epileptiform activities. First, we determine the stability of root loci, which reveals that the dynamical mechanism underlying epilepsy in the NPM is the loss of homeostatic control caused by the lack of balance between excitation and inhibition. Then, we design a PD type closed-loop controller to stabilize the unstable NPM such that the homeostatic equilibriums are maintained; we show that epileptiform activities are successfully suppressed. A graphical approach is employed to determine the stabilizing region of the PD controller in the parameter space, providing a theoretical guideline for the selection of the PD control parameters. Furthermore, we establish the relationship between the control parameters and the model parameters in the form of stabilizing regions to help understand the mechanism of suppressing epileptiform activities in the NPM. Simulations show that the PD-type closed-loop control strategy can effectively suppress epileptiform activities in the NPM. Project supported by the National Natural Science Foundation of China (Grant Nos. 61473208, 61025019, and 91132722), ONR MURI N000141010278, and NIH grant R01EY016281.

Structural sensing of interior sound for active control of noise in structural-acoustic cavities.

PubMed

Bagha, Ashok K; Modak, S V

2015-07-01

This paper proposes a method for structural sensing of acoustic potential energy for active control of noise in a structural-acoustic cavity. The sensing strategy aims at global control and works with a fewer number of sensors. It is based on the established concept of radiation modes and hence does not add too many states to the order of the system. Acoustic potential energy is sensed using a combination of a Kalman filter and a frequency weighting filter with the structural response measurements as the inputs. The use of Kalman filter also makes the system robust against measurement noise. The formulation of the strategy is presented using finite element models of the system including that of sensors and actuators so that it can be easily applied to practical systems. The sensing strategy is numerically evaluated in the framework of Linear Quadratic Gaussian based feedback control of interior noise in a rectangular box cavity with a flexible plate with single and multiple pairs of piezoelectric sensor-actuator patches when broadband disturbances act on the plate. The performance is compared with an "acoustic filter" that models the complete transfer function from the structure to the acoustic domain. The sensing performance is also compared with a direct estimation strategy.

Neural network-based sliding mode control for atmospheric-actuated spacecraft formation using switching strategy

NASA Astrophysics Data System (ADS)

Sun, Ran; Wang, Jihe; Zhang, Dexin; Shao, Xiaowei

2018-02-01

This paper presents an adaptive neural networks-based control method for spacecraft formation with coupled translational and rotational dynamics using only aerodynamic forces. It is assumed that each spacecraft is equipped with several large flat plates. A coupled orbit-attitude dynamic model is considered based on the specific configuration of atmospheric-based actuators. For this model, a neural network-based adaptive sliding mode controller is implemented, accounting for system uncertainties and external perturbations. To avoid invalidation of the neural networks destroying stability of the system, a switching control strategy is proposed which combines an adaptive neural networks controller dominating in its active region and an adaptive sliding mode controller outside the neural active region. An optimal process is developed to determine the control commands for the plates system. The stability of the closed-loop system is proved by a Lyapunov-based method. Comparative results through numerical simulations illustrate the effectiveness of executing attitude control while maintaining the relative motion, and higher control accuracy can be achieved by using the proposed neural-based switching control scheme than using only adaptive sliding mode controller.

Strategy aimed at reduction of sputum eosinophils decreases exacerbation rate in patients with asthma.

PubMed

Chlumský, J; Striz, I; Terl, M; Vondracek, J

2006-01-01

Under Global Initiative for Asthma guidelines, the clinical control of disease activity and the adjustment of treatment in patients with asthma are based on symptoms, use of rescue medication, lung function and peak expiratory flow measurement (standard strategy). We investigated whether a strategy to reduce the number of sputum eosinophils (EOS strategy) gives better clinical control and a lower exacerbation rate compared with the standard strategy. Fifty-five patients with moderate to severe asthma entered this open, randomized, parallel-group study and visited the out-patient department every 3 months for 18 months. The dose of corticosteroids was adjusted according to the standard strategy or the percentage of sputum eosinophils (EOS strategy). During the study period, the EOS strategy led to a significantly lower incidence of asthma exacerbations compared with the standard strategy group (0.22 and 0.78 exacerbations per year per patient, respectively). There were significant differences between the strategies in time to first exacerbation.

Multi-Objective Sliding Mode Control on Vehicle Cornering Stability with Variable Gear Ratio Actuator-Based Active Front Steering Systems

PubMed Central

Ma, Xinbo; Wong, Pak Kin; Zhao, Jing; Xie, Zhengchao

2016-01-01

Active front steering (AFS) is an emerging technology to improve the vehicle cornering stability by introducing an additional small steering angle to the driver’s input. This paper proposes an AFS system with a variable gear ratio steering (VGRS) actuator which is controlled by using the sliding mode control (SMC) strategy to improve the cornering stability of vehicles. In the design of an AFS system, different sensors are considered to measure the vehicle state, and the mechanism of the AFS system is also modelled in detail. Moreover, in order to improve the cornering stability of vehicles, two dependent objectives, namely sideslip angle and yaw rate, are considered together in the design of SMC strategy. By evaluating the cornering performance, Sine with Dwell and accident avoidance tests are conducted, and the simulation results indicate that the proposed SMC strategy is capable of improving the cornering stability of vehicles in practice. PMID:28036037

The vector of the tobacco epidemic: tobacco industry practices in low and middle-income countries.

PubMed

Lee, Sungkyu; Ling, Pamela M; Glantz, Stanton A

2012-03-01

To understand transnational tobacco companies' (TTCs) practices in low and middle-income countries which serve to block tobacco-control policies and promote tobacco use. Systematic review of published research on tobacco industry activities to promote tobacco use and oppose tobacco-control policies in low and middle-income countries. TTCs' strategies used in low and middle-income countries followed four main themes-economic activity; marketing/promotion; political activity; and deceptive/manipulative activity. Economic activity, including foreign investment and smuggling, was used to enter new markets. Political activities included lobbying, offering voluntary self-regulatory codes, and mounting corporate social responsibility campaigns. Deceptive activities included manipulation of science and use of third-party allies to oppose smoke-free policies, delay other tobacco-control policies, and maintain support of policymakers and the public for a pro-tobacco industry policy environment. TTCs used tactics for marketing, advertising, and promoting their brands that were tailored to specific market environments. These activities included direct and indirect tactis, targeting particular populations, and introducing new tobacco products designed to limit marketing restrictions and taxes, maintain the social acceptability of tobacco use, and counter tobacco-control efforts. TTCs have used similar strategies in high-income countries as these being described in low and middle-income countries. As required by FCTC Article 5.3, to counter tobacco industry pressures and to implement effective tobacco-control policies, governments and health professionals in low and middle-income countries should fully understand TTCs practices and counter them.

Stream chemistry responses to four range management strategies in eastern Oregon.

Treesearch

A.R. Tiedemann; D.A. Higgins; T.M. Quigley; H.R. Sanderson

1989-01-01

Responses of stream chemistry parameters, nitrate-N (NO3-N), phosphate (PO4), calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), and hydrogen ion activity (pH) were measured on 13 wildland watersheds managed at four different grazing strategies. Range management strategies tested were (A) no grazing, (B) grazing without control of livestock distribution (8.2 ha/...

Control of intestinal parasitic infections in Seychelles: a comprehensive and sustainable approach.

PubMed Central

Albonico, M.; Shamlaye, N.; Shamlaye, C.; Savioli, L.

1996-01-01

Intestinal parasitic infections have been perceived as a public health problem in Seychelles for decades. A comprehensive strategy to reduce morbidity and, in the long term, transmission of intestinal parasites has been implemented successfully since 1993. Management of the programme is integrated into the well established primary health care system, with control activities being undertaken through existing health facilities. The strategy is based on periodic chemotherapy of schoolchildren, intense health education and improvement of sanitation and safe water supply. The initial objectives of the control programme were met after 2 years of activities, with an overall reduction in prevalence of intestinal parasitic infections of 44%. The intensity of infection with Trichuris trichiura, the commonest parasite, was halved (from 780 to 370 eggs per g of faeces). The programme's integrated approach, in concert with political commitment and limited operational costs, is a warranty for the future sustainability of control activities. The programme can be seen as a model for other developing countries, even where health and socioeconomic conditions are different and the control of parasitic infections will need a much longer-term commitment. PMID:9060217

A Traction Control Strategy with an Efficiency Model in a Distributed Driving Electric Vehicle

PubMed Central

Lin, Cheng

2014-01-01

Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention. PMID:25197697

A traction control strategy with an efficiency model in a distributed driving electric vehicle.

PubMed

Lin, Cheng; Cheng, Xingqun

2014-01-01

Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model aiming at improving the fuel economy was built through an offline optimization stream within the two-dimensional design space composed of the acceleration pedal signal and the vehicle speed. The sliding mode control strategy for the joint roads and the efficiency model for the typical drive cycles were simulated. Simulation results show that the proposed driving control approach has the potential to apply to different road surfaces. It keeps the wheels' slip ratios within the stable zone and improves the fuel economy on the premise of tracking the driver's intention.

Plant extracts as potential mosquito larvicides

PubMed Central

Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

2012-01-01

Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non target organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed. PMID:22771587

Plant extracts as potential mosquito larvicides.

PubMed

Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

2012-05-01

Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non target organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed.

Neuro-fuzzy control of structures using acceleration feedback

NASA Astrophysics Data System (ADS)

Schurter, Kyle C.; Roschke, Paul N.

2001-08-01

This paper described a new approach for the reduction of environmentally induced vibration in constructed facilities by way of a neuro-fuzzy technique. The new control technique is presented and tested in a numerical study that involves two types of building models. The energy of each building is dissipated through magnetorheological (MR) dampers whose damping properties are continuously updated by a fuzzy controller. This semi-active control scheme relies on the development of a correlation between the accelerations of the building (controller input) and the voltage applied to the MR damper (controller output). This correlation forms the basis for the development of an intelligent neuro-fuzzy control strategy. To establish a context for assessing the effectiveness of the semi-active control scheme, responses to earthquake excitation are compared with passive strategies that have similar authority for control. According to numerical simulation, MR dampers are less effective control mechanisms than passive dampers with respect to a single degree of freedom (DOF) building model. On the other hand, MR dampers are predicted to be superior when used with multiple DOF structures for reduction of lateral acceleration.

Flow Navigation by Smart Microswimmers via Reinforcement Learning

NASA Astrophysics Data System (ADS)

Colabrese, Simona; Biferale, Luca; Celani, Antonio; Gustavsson, Kristian

2017-11-01

We have numerically modeled active particles which are able to acquire some limited knowledge of the fluid environment from simple mechanical cues and exert a control on their preferred steering direction. We show that those swimmers can learn effective strategies just by experience, using a reinforcement learning algorithm. As an example, we focus on smart gravitactic swimmers. These are active particles whose task is to reach the highest altitude within some time horizon, exploiting the underlying flow whenever possible. The reinforcement learning algorithm allows particles to learn effective strategies even in difficult situations when, in the absence of control, they would end up being trapped by flow structures. These strategies are highly nontrivial and cannot be easily guessed in advance. This work paves the way towards the engineering of smart microswimmers that solve difficult navigation problems. ERC AdG NewTURB 339032.

A stepped strategy that aims at the nationwide implementation of the Enhanced Recovery After Surgery programme in major gynaecological surgery: study protocol of a cluster randomised controlled trial.

PubMed

de Groot, Jeanny Ja; Maessen, José Mc; Slangen, Brigitte Fm; Winkens, Bjorn; Dirksen, Carmen D; van der Weijden, Trudy

2015-07-30

Enhanced Recovery After Surgery (ERAS) programmes aim at an early recovery after surgical trauma and consequently at a reduced length of hospitalisation. This paper presents the protocol for a study that focuses on large-scale implementation of the ERAS programme in major gynaecological surgery in the Netherlands. The trial will evaluate effectiveness and costs of a stepped implementation approach that is characterised by tailoring the intensity of implementation activities to the needs of organisations and local barriers for change, in comparison with the generic breakthrough strategy that is usually applied in large-scale improvement projects in the Netherlands. All Dutch hospitals authorised to perform major abdominal surgery in gynaecological oncology patients are eligible for inclusion in this cluster randomised controlled trial. The hospitals that already fully implemented the ERAS programme in their local perioperative management or those who predominantly admit gynaecological surgery patients to an external hospital replacement care facility will be excluded. Cluster randomisation will be applied at the hospital level and will be stratified based on tertiary status. Hospitals will be randomly assigned to the stepped implementation strategy or the breakthrough strategy. The control group will receive the traditional breakthrough strategy with three educational sessions and the use of plan-do-study-act cycles for planning and executing local improvement activities. The intervention group will receive an innovative stepped strategy comprising four levels of intensity of support. Implementation starts with generic low-cost activities and may build up to the highest level of tailored and labour-intensive activities. The decision for a stepwise increase in intensive support will be based on the success of implementation so far. Both implementation strategies will be completed within 1 year and evaluated on effect, process, and cost-effectiveness. The primary outcome is length of postoperative hospital stay. Additional outcome measures are length of recovery, guideline adherence, and mean implementation costs per patient. This study takes up the challenge to evaluate an efficient strategy for large-scale implementation. Comparing effectiveness and costs of two different approaches, this study will help to define a preferred strategy for nationwide dissemination of best practices. Dutch Trial Register NTR4058.

Cell-Mediated Immunity to Target the Persistent Human Immunodeficiency Virus Reservoir

PubMed Central

Montaner, Luis J.

2017-01-01

Abstract Effective clearance of virally infected cells requires the sequential activity of innate and adaptive immunity effectors. In human immunodeficiency virus (HIV) infection, naturally induced cell-mediated immune responses rarely eradicate infection. However, optimized immune responses could potentially be leveraged in HIV cure efforts if epitope escape and lack of sustained effector memory responses were to be addressed. Here we review leading HIV cure strategies that harness cell-mediated control against HIV in stably suppressed antiretroviral-treated subjects. We focus on strategies that may maximize target recognition and eradication by the sequential activation of a reconstituted immune system, together with delivery of optimal T-cell responses that can eliminate the reservoir and serve as means to maintain control of HIV spread in the absence of antiretroviral therapy (ART). As evidenced by the evolution of ART, we argue that a combination of immune-based strategies will be a superior path to cell-mediated HIV control and eradication. Available data from several human pilot trials already identify target strategies that may maximize antiviral pressure by joining innate and engineered T cell responses toward testing for sustained HIV remission and/or cure. PMID:28520969

Aggressive active case detection: a malaria control strategy based on the Brazilian model.

PubMed

Macauley, Cameron

2005-02-01

Since 1996, the Brazilian Ministry of Health has adopted a malaria control strategy known as aggressive active case detection (AACD) in which most or all members of every community are tested and treated for malaria on a monthly basis. The strategy attempts to identify and treat cases of asymptomatic malaria, which, if untreated, continue to transmit the infection. Malaria remains uncontrolled because almost all health care systems in the world rely on passive case detection: the treatment of only symptomatic cases of malaria. Research has shown conclusively that asymptomatic cases exist in any population where malaria transmission is stable and incidence is high: therefore passive case detection simply will not succeed in breaking the cycle of transmission. Numerous case studies show that malaria has been successfully controlled on a regional or national level by mass blood surveys. AACD is an effective malaria control strategy if used in conjunction with other methods, especially when (1) an effective treatment exists, (2) influx of potential carriers of the infection can be monitored, and (3) people are inclined to cooperate with monthly blood testing. AACD requires access to rapid diagnostic tests (RDTs), microscopy supplies, extensive human resources, and prompt, affordable, and effective treatment. AACD is compared to PCD in terms of clinical efficacy and cost effectiveness in a case study of malaria in the Brazilian Yanomami Indians. Where it is feasible, AACD could drastically reduce the incidence of malaria and should be an integral part of the World Health Organization's Roll Back Malaria strategy.

A practical cooling strategy for reducing the physiological strain associated with firefighting activity in the heat.

PubMed

Barr, D; Gregson, W; Sutton, L; Reilly, T

2009-04-01

The aim of this study was to establish whether a practical cooling strategy reduces the physiological strain during simulated firefighting activity in the heat. On two separate occasions under high ambient temperatures (49.6 +/- 1.8 degrees C, relative humidity (RH) 13 +/- 2%), nine male firefighters wearing protective clothing completed two 20-min bouts of treadmill walking (5 km/h, 7.5% gradient) separated by a 15-min recovery period, during which firefighters were either cooled (cool) via application of an ice vest and hand and forearm water immersion ( approximately 19 degrees C) or remained seated without cooling (control). There was no significant difference between trials in any of the dependent variables during the first bout of exercise. Core body temperature (37.72 +/- 0.34 vs. 38.21 +/- 0.17 degrees C), heart rate (HR) (81 +/- 9 vs. 96 +/- 17 beats/min) and mean skin temperature (31.22 +/- 1.04 degrees C vs. 33.31 +/- 1 degrees C) were significantly lower following the recovery period in cool compared with control (p < 0.05). Core body temperature remained consistently lower (0.49 +/- 0.02 degrees C; p < 0.01) throughout the second bout of activity in cool compared to control. Mean skin temperature, HR and thermal sensation were significantly lower during bout 2 in cool compared with control (p < 0.05). It is concluded that this practical cooling strategy is effective at reducing the physiological strain associated with demanding firefighting activity under high ambient temperatures.

DC Microgrids–Part I: A Review of Control Strategies and Stabilization Techniques

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

Dragicevic, Tomislav; Lu, Xiaonan; Vasquez, Juan

2015-01-01

This paper presents a review of control strategies, stability analysis, and stabilization techniques for dc microgrids (MGs). Overall control is systematically classified into local and coordinated control levels according to respective functionalities in each level. As opposed to local control, which relies only on local measurements, some line of communication between units needs to be made available in order to achieve the coordinated control. Depending on the communication method, three basic coordinated control strategies can be distinguished, i.e., decentralized, centralized, and distributed control. Decentralized control can be regarded as an extension of the local control since it is also basedmore » exclusively on local measurements. In contrast, centralized and distributed control strategies rely on digital communication technologies. A number of approaches using these three coordinated control strategies to achieve various control objectives are reviewed in this paper. Moreover, properties of dc MG dynamics and stability are discussed. This paper illustrates that tightly regulated point-of-load converters tend to reduce the stability margins of the system since they introduce negative impedances, which can potentially oscillate with lightly damped power supply input filters. It is also demonstrated that how the stability of the whole system is defined by the relationship of the source and load impedances, referred to as the minor loop gain. Several prominent specifications for the minor loop gain are reviewed. Finally, a number of active stabilization techniques are presented.« less

Strategies to improve the implementation of healthy eating, physical activity and obesity prevention policies, practices or programmes within childcare services.

PubMed

Wolfenden, Luke; Jones, Jannah; Williams, Christopher M; Finch, Meghan; Wyse, Rebecca J; Kingsland, Melanie; Tzelepis, Flora; Wiggers, John; Williams, Amanda J; Seward, Kirsty; Small, Tameka; Welch, Vivian; Booth, Debbie; Yoong, Sze Lin

2016-10-04

Despite the existence of effective interventions and best-practice guideline recommendations for childcare services to implement policies, practices and programmes to promote child healthy eating, physical activity and prevent unhealthy weight gain, many services fail to do so. The primary aim of the review was to examine the effectiveness of strategies aimed at improving the implementation of policies, practices or programmes by childcare services that promote child healthy eating, physical activity and/or obesity prevention. The secondary aims of the review were to:1. describe the impact of such strategies on childcare service staff knowledge, skills or attitudes;2. describe the cost or cost-effectiveness of such strategies;3. describe any adverse effects of such strategies on childcare services, service staff or children;4. examine the effect of such strategies on child diet, physical activity or weight status. We searched the following electronic databases on 3 August 2015: the Cochrane Central Register of Controlled trials (CENTRAL), MEDLINE, MEDLINE In Process, EMBASE, PsycINFO, ERIC, CINAHL and SCOPUS. We also searched reference lists of included trials, handsearched two international implementation science journals and searched the World Health Organization International Clinical Trials Registry Platform (www.who.int/ictrp/) and ClinicalTrials.gov (www.clinicaltrials.gov). We included any study (randomised or non-randomised) with a parallel control group that compared any strategy to improve the implementation of a healthy eating, physical activity or obesity prevention policy, practice or programme by staff of centre-based childcare services to no intervention, 'usual' practice or an alternative strategy. The review authors independently screened abstracts and titles, extracted trial data and assessed risk of bias in pairs; we resolved discrepancies via consensus. Heterogeneity across studies precluded pooling of data and undertaking quantitative assessment via meta-analysis. However, we narratively synthesised the trial findings by describing the effect size of the primary outcome measure for policy or practice implementation (or the median of such measures where a single primary outcome was not stated). We identified 10 trials as eligible and included them in the review. The trials sought to improve the implementation of policies and practices targeting healthy eating (two trials), physical activity (two trials) or both healthy eating and physical activity (six trials). Collectively the implementation strategies tested in the 10 trials included educational materials, educational meetings, audit and feedback, opinion leaders, small incentives or grants, educational outreach visits or academic detailing. A total of 1053 childcare services participated across all trials. Of the 10 trials, eight examined implementation strategies versus a usual practice control and two compared alternative implementation strategies. There was considerable study heterogeneity. We judged all studies as having high risk of bias for at least one domain.It is uncertain whether the strategies tested improved the implementation of policies, practices or programmes that promote child healthy eating, physical activity and/or obesity prevention. No intervention improved the implementation of all policies and practices targeted by the implementation strategies relative to a comparison group. Of the eight trials that compared an implementation strategy to usual practice or a no intervention control, however, seven reported improvements in the implementation of at least one of the targeted policies or practices relative to control. For these trials the effect on the primary implementation outcome was as follows: among the three trials that reported score-based measures of implementation the scores ranged from 1 to 5.1; across four trials reporting the proportion of staff or services implementing a specific policy or practice this ranged from 0% to 9.5%; and in three trials reporting the time (per day or week) staff or services spent implementing a policy or practice this ranged from 4.3 minutes to 7.7 minutes. The review findings also indicate that is it uncertain whether such interventions improve childcare service staff knowledge or attitudes (two trials), child physical activity (two trials), child weight status (two trials) or child diet (one trial). None of the included trials reported on the cost or cost-effectiveness of the intervention. One trial assessed the adverse effects of a physical activity intervention and found no difference in rates of child injury between groups. For all review outcomes, we rated the quality of the evidence as very low. The primary limitation of the review was the lack of conventional terminology in implementation science, which may have resulted in potentially relevant studies failing to be identified based on the search terms used in this review. Current research provides weak and inconsistent evidence of the effectiveness of such strategies in improving the implementation of policies and practices, childcare service staff knowledge or attitudes, or child diet, physical activity or weight status. Further research in the field is required.

Strategy of Water Pollution Control Base On Social Economic Activitiy, in Karang Mumus River, Samarinda East Kalimantan, Indonesia

NASA Astrophysics Data System (ADS)

Pramaningsih, Vita; Suprayogi, Slamet; Purnama, Setyawan

2018-02-01

Water Pollution in Karang Mumus River caused society behavior along the river. Daily activity such as bath, washing and defecate at the river. Garbage, sediment, domestic waste and flood are river problems should be solved. Purpose this research is make strategy of water pollution control in the Karang Mumus River. Method used observation in the field, interview to the society, industry, public activity along the river and government of environment department. Further create data using tool of Analysis Hierarchy Process (AHP) to get the strategy to control water pollution in the river. Actors have contribute pollution control are government, industry and society. Criteria to pollution control are society participation, low, human resources and sustainable. Alternative of pollution control are unit garbage storage; license loyalty for industry and waste; communal waste water installation; monitoring of water quality. Result for actor priority are government (0.4); Industry (0.4); Society (0.2). Result for priority criteria are society participation (0.338), low (0.288), human resources (0.205) and sustainable (0.169). Result for priority alternative are unit garbage storage (0.433); license loyalty for industry and waste (0.238); communal waste water installation (0.169); monitoring of water quality (0.161).

Aging and sequential modulations of poorer strategy effects: An EEG study in arithmetic problem solving.

PubMed

Hinault, Thomas; Lemaire, Patrick; Phillips, Natalie

2016-01-01

This study investigated age-related differences in electrophysiological signatures of sequential modulations of poorer strategy effects. Sequential modulations of poorer strategy effects refer to decreased poorer strategy effects (i.e., poorer performance when the cued strategy is not the best) on current problem following poorer strategy problems compared to after better strategy problems. Analyses on electrophysiological (EEG) data revealed important age-related changes in time, frequency, and coherence of brain activities underlying sequential modulations of poorer strategy effects. More specifically, sequential modulations of poorer strategy effects were associated with earlier and later time windows (i.e., between 200- and 550 ms and between 850- and 1250 ms). Event-related potentials (ERPs) also revealed an earlier onset in older adults, together with more anterior and less lateralized activations. Furthermore, sequential modulations of poorer strategy effects were associated with theta and alpha frequencies in young adults while these modulations were found in delta frequency and theta inter-hemispheric coherence in older adults, consistent with qualitatively distinct patterns of brain activity. These findings have important implications to further our understanding of age-related differences and similarities in sequential modulations of cognitive control processes during arithmetic strategy execution. Copyright © 2015 Elsevier B.V. All rights reserved.

Cost-Effectiveness of Chagas Disease Vector Control Strategies in Northwestern Argentina

PubMed Central

Vazquez-Prokopec, Gonzalo M.; Spillmann, Cynthia; Zaidenberg, Mario; Kitron, Uriel; Gürtler, Ricardo E.

2009-01-01

Background Control and prevention of Chagas disease rely mostly on residual spraying of insecticides. In Argentina, vector control shifted from a vertical to a fully horizontal strategy based on community participation between 1992 and 2004. The effects of such strategy on Triatoma infestans, the main domestic vector, and on disease transmission have not been assessed. Methods and Findings Based on retrospective (1993–2004) records from the Argentinean Ministry of Health for the Moreno Department, Northwestern Argentina, we performed a cost-effectiveness (CE) analysis and compared the observed CE of the fully horizontal vector control strategy with the expected CE for a vertical or a mixed (i.e., vertical attack phase followed by horizontal surveillance) strategy. Total direct costs (in 2004 US$) of the horizontal and mixed strategies were, respectively, 3.3 and 1.7 times lower than the costs of the vertical strategy, due to reductions in personnel costs. The estimated CE ratios for the vertical, mixed and horizontal strategies were US$132, US$82 and US$45 per averted human case, respectively. When per diems were excluded from the costs (i.e., simulating the decentralization of control activities), the CE of vertical, mixed and horizontal strategies was reduced to US$60, US$42 and US$32 per averted case, respectively. Conclusions and Significance The mixed strategy would have averted between 1.6 and 4.0 times more human cases than the fully horizontal strategy, and would have been the most cost-effective option to interrupt parasite transmission in the Department. In rural and dispersed areas where waning vertical vector programs cannot accomplish full insecticide coverage, alternative strategies need to be developed. If properly implemented, community participation represents not only the most appealing but also the most cost-effective alternative to accomplish such objectives. PMID:19156190

How much do I tell thee? Strategies for managing information to parents among American adolescents from Chinese, Mexican, and European backgrounds.

PubMed

Tasopoulos-Chan, Marina; Smetana, Judith G; Yau, Jenny P

2009-06-01

Strategies for managing information about activities to parents, including partial disclosure, avoidance, lying, and full disclosure, were examined in 479 American adolescents (M = 16.38 years, SD = 0.77) varying in generational status and from Mexican, Chinese, and European backgrounds. Information management strategies for personal, prudential, and overlapping (multifaceted) activities as defined within social domain theory were examined. With age, parental education, and generational status controlled, Chinese American adolescents partially disclosed more to mothers about personal and multifaceted activities than did Mexican American adolescents and more to fathers about personal activities than did European American teens. In contrast, European and Mexican American adolescents fully disclosed more to mothers about personal activities than did Chinese-origin adolescents. Strategies varied by generation among Chinese American youth; second-generation adolescents avoided discussing activities with parents more than did immigrants. Adolescents who fully disclosed about all activities and lied less about multifaceted and personal activities reported stronger endorsement of obligations to assist their families, more trust in parents, and less problem behavior. More depressed mood was associated with more lying about personal activities. Copyright 2009 APA, all rights reserved.

Mind your step: metabolic energy cost while walking an enforced gait pattern.

PubMed

Wezenberg, D; de Haan, A; van Bennekom, C A M; Houdijk, H

2011-04-01

The energy cost of walking could be attributed to energy related to the walking movement and energy related to balance control. In order to differentiate between both components we investigated the energy cost of walking an enforced step pattern, thereby perturbing balance while the walking movement is preserved. Nine healthy subjects walked three times at comfortable walking speed on an instrumented treadmill. The first trial consisted of unconstrained walking. In the next two trials, subject walked while following a step pattern projected on the treadmill. The steps projected were either composed of the averaged step characteristics (periodic trial), or were an exact copy including the variability of the steps taken while walking unconstrained (variable trial). Metabolic energy cost was assessed and center of pressure profiles were analyzed to determine task performance, and to gain insight into the balance control strategies applied. Results showed that the metabolic energy cost was significantly higher in both the periodic and variable trial (8% and 13%, respectively) compared to unconstrained walking. The variation in center of pressure trajectories during single limb support was higher when a gait pattern was enforced, indicating a more active ankle strategy. The increased metabolic energy cost could originate from increased preparatory muscle activation to ensure proper foot placement and a more active ankle strategy to control for lateral balance. These results entail that metabolic energy cost of walking can be influenced significantly by control strategies that do not necessary alter global gait characteristics. Copyright © 2011 Elsevier B.V. All rights reserved.

Tuberculosis in the tropics.

PubMed

Krause, V L; Britton, W J

1993-09-20

Until recently tuberculosis was considered a well controlled disease, at least in developed countries. In developing countries, more than seven million people are affected by active tuberculosis. This situation is exacerbated by poor infrastructure to support tuberculosis control measures and the interaction between tuberculosis and infection with the human immunodeficiency virus. The three major strategies for controlling tuberculosis remain BCG vaccination in children, appropriate preventive therapy and, most importantly, reducing the sources of infection through case finding and curative treatment. Research and resources to improve on these strategies should be given high priority by the international health community.

The Race against Time: Winning Strategies for Librarians.

ERIC Educational Resources Information Center

Lankford, Mary D.

1993-01-01

Discusses time management strategies that are particularly useful for school librarians. Highlights include setting realistic goals; active participation in learning and practicing time management skills; the use of day planners to help focus on goals and priorities; decision making for handling papers; controlling interruptions; and delegating…

Altered biomechanical strategies and medio-lateral control of the knee represent incomplete recovery of individuals with injury during single leg hop.

PubMed

Roos, Paulien E; Button, Kate; Sparkes, Valerie; van Deursen, Robert W M

2014-02-07

Anterior cruciate ligament (ACL) injury can result in failure to return to pre-injury activity levels and future osteoarthritis predisposition. Single leg hop is used in late rehabilitation to evaluate recovery and inform treatment but biomechanical understanding of this activity is insufficient. This study investigated single leg hop for distance aiming to evaluate if ACL patients had recovered: (1) landing strategies and (2) medio-lateral knee control. We hypothesized that patients with reconstructive surgery (ACLR) would have more similar landing strategies and knee control to healthy controls than patients treated conservatively (ACLD). 16 ACLD and 23 ACLR subjects were compared to 20 healthy controls (CONT). Kinematic and ground reaction force data were collected while subjects hopped their maximum distance. The main output parameters were hop distance, peak knee flexor angles and extensor moments and Fluency (a measure introduced to represent medio-lateral knee control). Statistical differences between ACL and control groups were analyzed using a general linear model univariate analysis, with COM velocity prior to landing as covariate. Hop distance was the smallest for ACLD and largest for CONT (p<0.001; ACLD 57.1±14.1; ACLR 75.1±17.8; CONT 77.7±14.07% height). ACLR used a similar kinematic strategy to CONT, but had a reduced peak knee extensor moment (p<0.001; ACLD 0.32±0.14; ACLR 0.31±0.16; CONT 0.42±0.13 BW.height). Fluency was reduced in both ACLD and ACLR (p=0.006; ACLD 0.13±0.34; ACLR 0.14±0.34; CONT 0.17±0.41s). Clinical practice uses hopping distance to evaluate ACL patients' recovery. This study demonstrated that aspects such as movement strategies and knee control need to be evaluated. © 2013 Published by Elsevier Ltd.

Physical Activity during the School Day

ERIC Educational Resources Information Center

Castelli, Darla M.; Ward, Kimberly

2012-01-01

In response to concerns that children are physically inactive, a Centers for Disease Control and Prevention committee developed school-based implementation strategies centered on the components of a Comprehensive School Physical Activity Program (CSPAP), composed of the physical education program, physical activity during the school day, staff…

Design of a New Integrated Structure of the Active Suspension System and Emergency Lane Change Test

NASA Astrophysics Data System (ADS)

Zhao, Jing-bo; Liu, Hai-mei; Zhang, Lan-chun; Bei, Shao-yi

2017-09-01

An integrated structure of the active suspension system was proposed in order to solve the problem of the individual control of the height of the body or the adjustable damping of the active suspension system of the electric vehicle, which improve the vibration reduction performance of the vehicle. The air bag was used to replace the traditional spiral spring, and the traditional shock absorber was replaced by the damping adjustable shock absorber, and the control module received the body acceleration sensor and the horizontal height sensor signal. The system controlled adjustable damping coefficient of shock absorber through the height of the car body the output of the air pump relay and the height control valve and the output of the electromagnetic valve of the adjustable damping shock absorber, and the emergency lane change test was carried out under different modes of speed of 60km/h. The experimental results indicated that the damping value was greater, average roll angle, yaw angle and average vehicle lateral acceleration were small when vehicle body was in the state of emergency lane change, which verified the feasibility of the integrated control strategy and structure design of the active suspension system. The research has important theoretical research value and engineering application prospect for designing and controlling strategy of vehicle chassis integrated control system.

Trust, control strategies and allocation of function in human-machine systems.

PubMed

Lee, J; Moray, N

1992-10-01

As automated controllers supplant human intervention in controlling complex systems, the operators' role often changes from that of an active controller to that of a supervisory controller. Acting as supervisors, operators can choose between automatic and manual control. Improperly allocating function between automatic and manual control can have negative consequences for the performance of a system. Previous research suggests that the decision to perform the job manually or automatically depends, in part, upon the trust the operators invest in the automatic controllers. This paper reports an experiment to characterize the changes in operators' trust during an interaction with a semi-automatic pasteurization plant, and investigates the relationship between changes in operators' control strategies and trust. A regression model identifies the causes of changes in trust, and a 'trust transfer function' is developed using time series analysis to describe the dynamics of trust. Based on a detailed analysis of operators' strategies in response to system faults we suggest a model for the choice between manual and automatic control, based on trust in automatic controllers and self-confidence in the ability to control the system manually.

The Influence of Encoding Strategy on Episodic Memory and Cortical Activity in Schizophrenia

PubMed Central

Haut, Kristen; Csernansky, John G.; Barch, Deanna M.

2005-01-01

Background: Recent work suggests that episodic memory deficits in schizophrenia may be related to disturbances of encoding or retrieval. Schizophrenia patients appear to benefit from instruction in episodic memory strategies. We tested the hypothesis that providing effective encoding strategies to schizophrenia patients enhances encoding-related brain activity and recognition performance. Methods: Seventeen schizophrenia patients and 26 healthy comparison subjects underwent functional magnetic resonance imaging scans while performing incidental encoding tasks of words and faces. Subjects were required to make either deep (abstract/concrete) or shallow (alphabetization) judgments for words and deep (gender) judgments for faces, followed by subsequent recognition tests. Results: Schizophrenia and comparison subjects recognized significantly more words encoded deeply than shallowly, activated regions in inferior frontal cortex (Brodmann area 45/47) typically associated with deep and successful encoding of words, and showed greater left frontal activation for the processing of words compared with faces. However, during deep encoding and material-specific processing (words vs. faces), participants with schizophrenia activated regions not activated by control subjects, including several in prefrontal cortex. Conclusions: Our findings suggest that a deficit in use of effective strategies influences episodic memory performance in schizophrenia and that abnormalities in functional brain activation persist even when such strategies are applied. PMID:15992522

Control Strategies for the DAB Based PV Interface System

PubMed Central

El-Helw, Hadi M.; Al-Hasheem, Mohamed; Marei, Mostafa I.

2016-01-01

This paper presents an interface system based on the Dual Active Bridge (DAB) converter for Photovoltaic (PV) arrays. Two control strategies are proposed for the DAB converter to harvest the maximum power from the PV array. The first strategy is based on a simple PI controller to regulate the terminal PV voltage through the phase shift angle of the DAB converter. The Perturb and Observe (P&O) Maximum Power Point Tracking (MPPT) technique is utilized to set the reference of the PV terminal voltage. The second strategy presented in this paper employs the Artificial Neural Network (ANN) to directly set the phase shift angle of the DAB converter that results in harvesting maximum power. This feed-forward strategy overcomes the stability issues of the feedback strategy. The proposed PV interface systems are modeled and simulated using MATLAB/SIMULINK and the EMTDC/PSCAD software packages. The simulation results reveal accurate and fast response of the proposed systems. The dynamic performance of the proposed feed-forward strategy outdoes that of the feedback strategy in terms of accuracy and response time. Moreover, an experimental prototype is built to test and validate the proposed PV interface system. PMID:27560138

Control Oriented Modeling and Validation of Aeroservoelastic Systems

NASA Technical Reports Server (NTRS)

Crowder, Marianne; deCallafon, Raymond (Principal Investigator)

2002-01-01

Lightweight aircraft design emphasizes the reduction of structural weight to maximize aircraft efficiency and agility at the cost of increasing the likelihood of structural dynamic instabilities. To ensure flight safety, extensive flight testing and active structural servo control strategies are required to explore and expand the boundary of the flight envelope. Aeroservoelastic (ASE) models can provide online flight monitoring of dynamic instabilities to reduce flight time testing and increase flight safety. The success of ASE models is determined by the ability to take into account varying flight conditions and the possibility to perform flight monitoring under the presence of active structural servo control strategies. In this continued study, these aspects are addressed by developing specific methodologies and algorithms for control relevant robust identification and model validation of aeroservoelastic structures. The closed-loop model robust identification and model validation are based on a fractional model approach where the model uncertainties are characterized in a closed-loop relevant way.

Particle swarm optimization algorithm based parameters estimation and control of epileptiform spikes in a neural mass model

NASA Astrophysics Data System (ADS)

Shan, Bonan; Wang, Jiang; Deng, Bin; Wei, Xile; Yu, Haitao; Zhang, Zhen; Li, Huiyan

2016-07-01

This paper proposes an epilepsy detection and closed-loop control strategy based on Particle Swarm Optimization (PSO) algorithm. The proposed strategy can effectively suppress the epileptic spikes in neural mass models, where the epileptiform spikes are recognized as the biomarkers of transitions from the normal (interictal) activity to the seizure (ictal) activity. In addition, the PSO algorithm shows capabilities of accurate estimation for the time evolution of key model parameters and practical detection for all the epileptic spikes. The estimation effects of unmeasurable parameters are improved significantly compared with unscented Kalman filter. When the estimated excitatory-inhibitory ratio exceeds a threshold value, the epileptiform spikes can be inhibited immediately by adopting the proportion-integration controller. Besides, numerical simulations are carried out to illustrate the effectiveness of the proposed method as well as the potential value for the model-based early seizure detection and closed-loop control treatment design.

Sequencing bilateral robot-assisted arm therapy and constraint-induced therapy improves reach to press and trunk kinematics in patients with stroke.

PubMed

Hsieh, Yu-wei; Liing, Rong-jiuan; Lin, Keh-chung; Wu, Ching-yi; Liou, Tsan-hon; Lin, Jui-chi; Hung, Jen-wen

2016-03-22

The combination of robot-assisted therapy (RT) and a modified form of constraint-induced therapy (mCIT) shows promise for improving motor function of patients with stroke. However, whether the changes of motor control strategies are concomitant with the improvements in motor function after combination of RT and mCIT (RT + mCIT) is unclear. This study investigated the effects of the sequential combination of RT + mCIT compared with RT alone on the strategies of motor control measured by kinematic analysis and on motor function and daily performance measured by clinical scales. The study enrolled 34 patients with chronic stroke. The data were derived from part of a single-blinded randomized controlled trial. Participants in the RT + mCIT and RT groups received 20 therapy sessions (90 to 105 min/day, 5 days for 4 weeks). Patients in the RT + mCIT group received 10 RT sessions for first 2 weeks and 10 mCIT sessions for the next 2 weeks. The Bi-Manu-Track was used in RT sessions to provide bilateral practice of wrist and forearm movements. The primary outcome was kinematic variables in a task of reaching to press a desk bell. Secondary outcomes included scores on the Wolf Motor Function Test, Functional Independence Measure, and Nottingham Extended Activities of Daily Living. All outcome measures were administered before and after intervention. RT + mCIT and RT demonstrated different benefits on motor control strategies. RT + mCIT uniquely improved motor control strategies by reducing shoulder abduction, increasing elbow extension, and decreasing trunk compensatory movement during the reaching task. Motor function and quality of the affected limb was improved, and patients achieved greater independence in instrumental activities of daily living. Force generation at movement initiation was improved in the patients who received RT. A combination of RT and mCIT could be an effective approach to improve stroke rehabilitation outcomes, achieving better motor control strategies, motor function, and functional independence of instrumental activities of daily living. ClinicalTrials.gov. NCT01727648.

Self-Control in School-Age Children

ERIC Educational Resources Information Center

Duckworth, Angela L.; Gendler, Tamar Szabó; Gross, James J.

2014-01-01

Conflicts between immediately rewarding activities and more enduringly valued goals abound in the lives of school-age children. Such conflicts call upon children to exercise self-control, a competence that depends in part on the mastery of metacognitive, prospective strategies. The "process model of self-control" organizes these…

Dynamic Determinants of the Uncontrolled Manifold during Human Quiet Stance

PubMed Central

Suzuki, Yasuyuki; Morimoto, Hiroki; Kiyono, Ken; Morasso, Pietro G.; Nomura, Taishin

2016-01-01

Human postural sway during stance arises from coordinated multi-joint movements. Thus, a sway trajectory represented by a time-varying postural vector in the multiple-joint-angle-space tends to be constrained to a low-dimensional subspace. It has been proposed that the subspace corresponds to a manifold defined by a kinematic constraint, such that the position of the center of mass (CoM) of the whole body is constant in time, referred to as the kinematic uncontrolled manifold (kinematic-UCM). A control strategy related to this hypothesis (CoM-control-strategy) claims that the central nervous system (CNS) aims to keep the posture close to the kinematic-UCM using a continuous feedback controller, leading to sway patterns that mostly occur within the kinematic-UCM, where no corrective control is exerted. An alternative strategy proposed by the authors (intermittent control-strategy) claims that the CNS stabilizes posture by intermittently suspending the active feedback controller, in such a way to allow the CNS to exploit a stable manifold of the saddle-type upright equilibrium in the state-space of the system, referred to as the dynamic-UCM, when the state point is on or near the manifold. Although the mathematical definitions of the kinematic- and dynamic-UCM are completely different, both UCMs play similar roles in the stabilization of multi-joint upright posture. The purpose of this study was to compare the dynamic performance of the two control strategies. In particular, we considered a double-inverted-pendulum-model of postural control, and analyzed the two UCMs defined above. We first showed that the geometric configurations of the two UCMs are almost identical. We then investigated whether the UCM-component of experimental sway could be considered as passive dynamics with no active control, and showed that such UCM-component mainly consists of high frequency oscillations above 1 Hz, corresponding to anti-phase coordination between the ankle and hip. We also showed that this result can be better characterized by an eigenfrequency associated with the dynamic-UCM. In summary, our analysis highlights the close relationship between the two control strategies, namely their ability to simultaneously establish small CoM variations and postural stability, but also make it clear that the intermittent control hypothesis better explains the spectral characteristics of sway. PMID:27999535

Dynamic Determinants of the Uncontrolled Manifold during Human Quiet Stance.

PubMed

Suzuki, Yasuyuki; Morimoto, Hiroki; Kiyono, Ken; Morasso, Pietro G; Nomura, Taishin

2016-01-01

Human postural sway during stance arises from coordinated multi-joint movements. Thus, a sway trajectory represented by a time-varying postural vector in the multiple-joint-angle-space tends to be constrained to a low-dimensional subspace. It has been proposed that the subspace corresponds to a manifold defined by a kinematic constraint, such that the position of the center of mass (CoM) of the whole body is constant in time, referred to as the kinematic uncontrolled manifold ( kinematic-UCM ). A control strategy related to this hypothesis ( CoM-control-strategy ) claims that the central nervous system (CNS) aims to keep the posture close to the kinematic-UCM using a continuous feedback controller, leading to sway patterns that mostly occur within the kinematic-UCM, where no corrective control is exerted. An alternative strategy proposed by the authors ( intermittent control-strategy ) claims that the CNS stabilizes posture by intermittently suspending the active feedback controller, in such a way to allow the CNS to exploit a stable manifold of the saddle-type upright equilibrium in the state-space of the system, referred to as the dynamic-UCM , when the state point is on or near the manifold. Although the mathematical definitions of the kinematic- and dynamic-UCM are completely different, both UCMs play similar roles in the stabilization of multi-joint upright posture. The purpose of this study was to compare the dynamic performance of the two control strategies. In particular, we considered a double-inverted-pendulum-model of postural control, and analyzed the two UCMs defined above. We first showed that the geometric configurations of the two UCMs are almost identical. We then investigated whether the UCM-component of experimental sway could be considered as passive dynamics with no active control, and showed that such UCM-component mainly consists of high frequency oscillations above 1 Hz, corresponding to anti-phase coordination between the ankle and hip. We also showed that this result can be better characterized by an eigenfrequency associated with the dynamic-UCM. In summary, our analysis highlights the close relationship between the two control strategies, namely their ability to simultaneously establish small CoM variations and postural stability, but also make it clear that the intermittent control hypothesis better explains the spectral characteristics of sway.

Assessment of semi-active friction dampers

NASA Astrophysics Data System (ADS)

dos Santos, Marcelo Braga; Coelho, Humberto Tronconi; Lepore Neto, Francisco Paulo; Mafhoud, Jarir

2017-09-01

The use of friction dampers has been widely proposed for a variety of mechanical systems for which applying viscoelastic materials, fluid based dampers or other viscous dampers is impossible. An important example is the application of friction dampers in aircraft engines to reduce the blades' vibration amplitudes. In most cases, friction dampers have been studied in a passive manner, but significant improvements can be achieved by controlling the normal force in the contact region. The aim of this paper is to present and study five control strategies for friction dampers based on three different hysteresis cycles by using the Harmonic Balance Method (HBM), a numerical and experimental analysis. The first control strategy uses the friction force as a resistance when the system is deviating from its equilibrium position. The second control strategy maximizes the energy removal in each harmonic oscillation cycle by calculating the optimal normal force based on the last displacement peak. The third control strategy combines the first strategy with the homogenous modulation of the friction force. Finally, the last two strategies attempt to predict the system's movement based on its velocity and acceleration and our knowledge of its physical properties. Numerical and experimental studies are performed with these five strategies, which define the performance metrics. The experimental testing rig is fully identified and its parameters are used for numerical simulations. The obtained results show the satisfactory performance of the friction damper and selected strategy and the suitable agreement between the numerical and experimental results.

Active flutter suppression using dipole filters

NASA Technical Reports Server (NTRS)

Srinathkumar, S.; Waszak, Martin R.

1992-01-01

By using traditional control concepts of gain root locus, the active suppression of a flutter mode of a flexible wing is examined. It is shown that the attraction of the unstable mode towards a critical system zero determines the degree to which the flutter mode can be stabilized. For control situations where the critical zero is adversely placed in the complex plane, a novel compensation scheme called a 'Dipole' filter is proposed. This filter ensures that the flutter mode is stabilized with acceptable control energy. The control strategy is illustrated by designing flutter suppression laws for an active flexible wing (AFW) wind-tunnel model, where minimal control effort solutions are mandated by control rate saturation problems caused by wind-tunnel turbulence.

Life satisfaction and its correlates in older women with osteoarthritis.

PubMed

Tak, Sunghee H; Laffrey, Shirley C

2003-01-01

To identify the relationships among functional disability, chronic daily stress, coping strategies, beliefs about personal control, social support, and life satisfaction in older women with osteoarthritis. A descriptive, correlational design was used. The study participants were 107 women aged 60 years or older. Study participants completed six survey questionnaires and a demographic form. Bivariate correlational analyses showed that older women with poorer functional ability experienced greater chronic daily stress, reported more frequent use of emotion-focused coping strategies, and had a higher chance health locus of control. A hierarchic regression analysis revealed that the perceived social support and internal health locus of control significantly contributed to the prediction of life satisfaction after demographic, illness-related, and stress-related variables were controlled. Stress management strategies matched to the participants' style of coping process can increase their sense of control over their health and enhance their social networks and activities.

Soil nitrogen mineralization and enzymatic activities in fire and fire surrogate treatments in California

Treesearch

J. R. Miesel; R. E. J. Boerner; C. N. Skinner

2011-01-01

Forest thinning and prescribed fire are management strategies used to reduce hazardous fuel loads and catastrophic wildfires in western mixed-conifer forests. We evaluated effects of thinning (Thin) and prescribed fire (Burn), alone and in combination (Thin+Burn), on N transformations and microbial enzyme activities relative to an untreated control (Control) at 1 and 3...

Coping with examinations: exploring relationships between students' coping strategies, implicit theories of ability, and perceived control.

PubMed

Doron, Julie; Stephan, Yannick; Boiché, Julie; Le Scanff, Christine

2009-09-01

Relatively little is known about the contribution of students' beliefs regarding the nature of academic ability (i.e. their implicit theories) on strategies used to deal with examinations. This study applied Dweck's socio-cognitive model of achievement motivation to better understand how students cope with examinations. It was expected that students' implicit theories of academic ability would be related to their use of particular coping strategies to deal with exam-related stress. Additionally, it was predicted that perceived control over exams acts as a mediator between implicit theories of ability and coping. Four hundred and ten undergraduate students (263 males, 147 females), aged from 17 to 26 years old (M=19.73, SD=1.46) were volunteers for the present study. Students completed measures of coping, implicit theories of academic ability, and perception of control over academic examinations during regular classes in the first term of the university year. Multiple regression analyses revealed that incremental beliefs of ability significantly and positively predicted active coping, planning, venting of emotions, seeking social support for emotional and instrumental reasons, whereas entity beliefs positively predicted behavioural disengagement and negatively predicted active coping and acceptance. In addition, analyses revealed that entity beliefs of ability were related to coping strategies through students' perception of control over academic examinations. These results confirm that exam-related coping varies as a function of students' beliefs about the nature of academic ability and their perceptions of control when approaching examinations.

Movement Strategies among Groups of Chronic Ankle Instability, Coper, and Control.

PubMed

Son, S Jun; Kim, Hyunsoo; Seeley, Matthew K; Hopkins, J Ty

2017-08-01

Comprehensive evaluation of movement strategies during functional movement is a difficult undertaking. Because of this challenge, studied movements have been oversimplified. Furthermore, evaluating movement strategies at only a discrete time point(s) provide limited insight into how movement strategies may change or adapt in chronic ankle instability (CAI) patients. This study aimed to identify abnormal movement strategies in individuals with a history of ankle sprain injury during a sports maneuver compared with healthy controls. Sixty-six participants, consisting of 22 CAI patients, 22 ankle sprain copers, and 22 healthy controls, participated in this study. Functional profiles of lower extremity kinematics, kinetics, and EMG activation from initial contact (0% of stance) to toe-off (100% of stance) were collected and analyzed during a jump landing/cutting task using a functional data analysis approach. Compared with copers, CAI patients displayed landing positions of less plantarflexion, less inversion, more knee flexion, more hip flexion, and less hip abduction during the first 25% of stance. However, restricted dorsiflexion angle was observed in both CAI patients and copers relative to controls during the midlanding to mid-side-cutting phase when the ankle and knee reached its peak range of motion (e.g., dorsiflexion and knee flexion). Reduced EMG activation of tibialis anterior, peroneus longus, medial gastrocnemius, and gluteus medius may be due to altered kinematics that reduce muscular demands on the involved muscles. CAI patients displayed altered movement strategies, perhaps in an attempt to avoid perceived positions of risk. Although sagittal joint positions seemed to increase the external torque on the knee and hip extensors, frontal joint positions appeared to reduce the muscular demands on evertor and hip abductor muscles.

Weight control behaviors of highly successful weight loss maintainers: the Portuguese Weight Control Registry.

PubMed

Santos, Inês; Vieira, Paulo N; Silva, Marlene N; Sardinha, Luís B; Teixeira, Pedro J

2017-04-01

To describe key behaviors reported by participants in the Portuguese Weight Control Registry and to determine associations between these behaviors and weight loss maintenance. A total of 388 adults participated in this cross-sectional study. Assessments included demographic information, weight history, weight loss and weight maintenance strategies, dietary intake, and physical activity. Participants lost on average 18 kg, which they had maintained for ~28 months. Their average dietary intake was 2199 kcal/day, with 33 % of energy coming from fat. About 78 % of participants engaged in levels of moderate-plus-vigorous physical activity exceeding 150 min/week (51 % above 250 min/week), with men accumulating 82 more minutes than women (p < 0.05). The most frequently reported strategies for both weight loss and maintenance were keeping healthy foods at home, consuming vegetables regularly, and having daily breakfast. Greater weight loss maintenance was associated with higher levels of physical activity, walking, weight self-monitoring, establishing specific goals, and with reduced portion size use, reduced consumption of carbohydrates, and increased consumption of protein, (p < 0.05). Results indicate that weight loss maintenance is possible through the adoption of a nutritionally-balanced diet and regular participation in physical activity, but also suggest that adopting different (and, to a degree, individualized) set of behavioral strategies is key for achieving success.

Dynamic and kinematic strategies for head movement control

NASA Technical Reports Server (NTRS)

Peterson, B. W.; Choi, H.; Hain, T.; Keshner, E.; Peng, G. C.

2001-01-01

This paper describes our analysis of the complex head-neck system using a combination of experimental and modeling approaches. Dynamical analysis of head movements and EMG activation elicited by perturbation of trunk position has examined functional contributions of biomechanically and neurally generated forces in lumped systems with greatly simplified kinematics. This has revealed that visual and voluntary control of neck muscles and the dynamic and static vestibulocollic and cervicocollic reflexes preferentially govern head-neck system state in different frequency domains. It also documents redundant control, which allows the system to compensate for lesions and creates a potential for substantial variability within and between subjects. Kinematic studies have indicated the existence of reciprocal and co-contraction strategies for voluntary force generation, of a vestibulocollic strategy for stabilizing the head during body perturbations and of at least two strategies for voluntary head tracking. Each strategy appears to be executed by a specific muscle synergy that is presumably optimized to efficiently meet the demands of the task.

Effectiveness of the graded motor imagery to improve hand function in patients with distal radius fracture: A randomized controlled trial.

PubMed

Dilek, Burcu; Ayhan, Cigdem; Yagci, Gozde; Yakut, Yavuz

Single-blinded randomized controlled trial. Pain management is essential in the early stages of the rehabilitation of distal radius fractures (DRFx). Pain intensity at the acute stage is considered important for determining the individual recovery process, given that higher pain intensity and persistent pain duration negatively affect the function and cortical activity of pain response. Graded motor imagery (GMI) and its components are recent pain management strategies, established on a neuroscience basis. To investigate the effectiveness of GMI in hand function in patients with DRFx. Thirty-six participants were randomly allocated to either GMI (n = 17; 52.59 [9.8] years) or control (n = 19; 47.16 [10.5] years) groups. The GMI group received imagery treatment in addition to traditional rehabilitation, and the control group received traditional rehabilitation for 8 weeks. The assessments included pain at rest and during activity using the visual analog scale, wrist and forearm active range of motion (ROM) with universal goniometer, grip strength with the hydraulic dynamometer (Jamar; Bolingbrook, IL), and upper extremity functional status using the Disability of the Arm, Shoulder and Hand Questionnaire, and the Michigan Hand Questionnaire. Assessments were performed twice at baseline and at the end of the eighth week. The GMI group showed greater improvement in pain intensity (during rest, 2.24; activity, 6.18 points), wrist ROM (flexion, -40.59; extension, -45.59; radial deviation, -25.59; and ulnar deviation, -26.77 points) and forearm ROM (supination, -43.82 points), and functional status (Disability of the Arm, Shoulder and Hand Questionnaire, 38.00; Michigan Hand Questionnaire, -32.53 points) when compared with the control group (for all, P < .05). The cortical model of pathological pain suggests new strategies established on a neuroscience basis. These strategies aim to normalize the cortical proprioceptive representation and reduce pain. One of these recent strategies, GMI appears to provide beneficial effects to control pain, improve grip strength, and increase upper extremity functions in patients with DRFx. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Active acoustical impedance using distributed electrodynamical transducers.

PubMed

Collet, M; David, P; Berthillier, M

2009-02-01

New miniaturization and integration capabilities available from emerging microelectromechanical system (MEMS) technology will allow silicon-based artificial skins involving thousands of elementary actuators to be developed in the near future. SMART structures combining large arrays of elementary motion pixels coated with macroscopic components are thus being studied so that fundamental properties such as shape, stiffness, and even reflectivity of light and sound could be dynamically adjusted. This paper investigates the acoustic impedance capabilities of a set of distributed transducers connected with a suitable controlling strategy. Research in this domain aims at designing integrated active interfaces with a desired acoustical impedance for reaching an appropriate global acoustical behavior. This generic problem is intrinsically connected with the control of multiphysical systems based on partial differential equations (PDEs) and with the notion of multiscaled physics when a dense array of electromechanical systems (or MEMS) is considered. By using specific techniques based on PDE control theory, a simple boundary control equation capable of annihilating the wave reflections has been built. The obtained strategy is also discretized as a low order time-space operator for experimental implementation by using a dense network of interlaced microphones and loudspeakers. The resulting quasicollocated architecture guarantees robustness and stability margins. This paper aims at showing how a well controlled semidistributed active skin can substantially modify the sound transmissibility or reflectivity of the corresponding homogeneous passive interface. In Sec. IV, numerical and experimental results demonstrate the capabilities of such a method for controlling sound propagation in ducts. Finally, in Sec. V, an energy-based comparison with a classical open-loop strategy underlines the system's efficiency.

Evaluation of Commercial Agrochemicals as New Tools for Malaria Vector Control.

PubMed

Hoppé, Mark; Hueter, Ottmar F; Bywater, Andy; Wege, Philip; Maienfisch, Peter

2016-10-01

Malaria is a vector-borne and life-threatening disease caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. The vector control insecticide market represents a small fraction of the crop protection market and is estimated to be valued at up to $500 million at the active ingredient level. Insecticide resistance towards the current WHOPES-approved products urgently requires the development of new tools to protect communities against the transmission of malaria. The evaluation of commercial products for malaria vector control is a viable and cost effective strategy to identify new malaria vector control products. Several examples of such spin-offs from crop protection insecticides are already evidencing the success of this strategy, namely pirimiphos-methyl for indoor residual sprays and spinosad, diflubenzuron, novaluron, and pyriproxifen for mosquito larvae control, a supplementary technology for control of malaria vectors. In our study the adulticidal activities of 81 insecticides representing 23 insecticidal modes of action classes, 34 fungicides from 6 fungicidal mode of action classes and 15 herbicides from 2 herbicidal modes of action classes were tested in a newly developed screening system. WHOPES approved insecticides for malaria vector control consistently caused 80-100% mortality of adult Anopheles stephensi at application rates between 0.2 and 20 mg active ingradient (AI) litre -1 . Chlorfenapyr, fipronil, carbosulfan and endosulfan showed the expected good activity. Four new insecticides and three fungicides with promising activity against adult mosquitoes were identified, namely the insecticides acetamiprid, thiamethoxam, thiocyclam and metaflumizone and the fungicides diflumetorin, picoxystrobin, and fluazinam. Some of these compounds certainly deserve to be further evaluated for malaria vector control. This is the first report describing good activity of commercial fungicides against malaria vectors.

The vector of the tobacco epidemic: tobacco industry practices in low and middle-income countries

PubMed Central

Lee, Sungkyu; Ling, Pamela M.; Glantz, Stanton A.

2012-01-01

Purpose To understand transnational tobacco companiesr’ (TTCs) practices in low and middle-income countries which serve to block tobacco-control policies and promote tobacco use. Methods Systematic review of published research on tobacco industry activities to promote tobacco use and oppose tobacco-control policies in low and middle-income countries. Results TTCs’ strategies used in low and middle-income countries followed four main themes—economic activity; marketing/promotion; political activity; and deceptive/manipulative activity. Economic activity, including foreign investment and smuggling, was used to enter new markets. Political activities included lobbying, offering voluntary self-regulatory codes, and mounting corporate social responsibility campaigns. Deceptive activities included manipulation of science and use of third-party allies to oppose smoke-free policies, delay other tobacco-control policies, and maintain support of policymakers and the public for a pro-tobacco industry policy environment. TTCs used tactics for marketing, advertising, and promoting their brands that were tailored to specific market environments. These activities included direct and indirect tactis, targeting particular populations, and introducing new tobacco products designed to limit marketing restrictions and taxes, maintain the social acceptability of tobacco use, and counter tobacco-control efforts. Conclusions TTCs have used similar strategies in high-income countries as these being described in low and middle-income countries. As required by FCTC Article 5.3, to counter tobacco industry pressures and to implement effective tobacco-control policies, governments and health professionals in low and middle-income countries should fully understand TTCs practices and counter them. PMID:22370696

Perceived Control and Social Activity in Midlife and Older Age: A Reciprocal Association? Findings From the German Ageing Survey.

PubMed

Curtis, Rachel G; Huxhold, Oliver; Windsor, Tim D

2018-06-14

Perceived control may promote social activity in older adults because individuals with greater perceived control have greater confidence in their ability to achieve outcomes and are more likely to choose difficult activities, show persistence, and employ strategies to overcome challenges. Cross-sectional research has linked perceived control with social activity in life span and older adult samples but provides little insight into the direction of influence. We examined reciprocal associations between perceived control and social activity in order to establish temporal sequencing, which is one prerequisite for determining potential causation. Participants were 14,126 midlife and older adults from the German Ageing Survey. Using cross-lagged autoregressive modeling with age as the time metric (40-87 years), we examined reciprocal 3-year lagged associations between perceived control and social activity, while controlling for concurrent associations. Perceived control significantly predicted social activity 3 years later. Reciprocally, social activity significantly predicted perceived control 3 years later. The influence of perceived control on social activity was greater than the influence of social activity on perceived control. The finding that perceived control significantly predicts future social activity has potential implications for developing interventions aimed at promoting social activity in midlife and older adults.

Optimal management strategies in variable environments: Stochastic optimal control methods

USGS Publications Warehouse

Williams, B.K.

1985-01-01

Dynamic optimization was used to investigate the optimal defoliation of salt desert shrubs in north-western Utah. Management was formulated in the context of optimal stochastic control theory, with objective functions composed of discounted or time-averaged biomass yields. Climatic variability and community patterns of salt desert shrublands make the application of stochastic optimal control both feasible and necessary. A primary production model was used to simulate shrub responses and harvest yields under a variety of climatic regimes and defoliation patterns. The simulation results then were used in an optimization model to determine optimal defoliation strategies. The latter model encodes an algorithm for finite state, finite action, infinite discrete time horizon Markov decision processes. Three questions were addressed: (i) What effect do changes in weather patterns have on optimal management strategies? (ii) What effect does the discounting of future returns have? (iii) How do the optimal strategies perform relative to certain fixed defoliation strategies? An analysis was performed for the three shrub species, winterfat (Ceratoides lanata), shadscale (Atriplex confertifolia) and big sagebrush (Artemisia tridentata). In general, the results indicate substantial differences among species in optimal control strategies, which are associated with differences in physiological and morphological characteristics. Optimal policies for big sagebrush varied less with variation in climate, reserve levels and discount rates than did either shadscale or winterfat. This was attributed primarily to the overwintering of photosynthetically active tissue and to metabolic activity early in the growing season. Optimal defoliation of shadscale and winterfat generally was more responsive to differences in plant vigor and climate, reflecting the sensitivity of these species to utilization and replenishment of carbohydrate reserves. Similarities could be seen in the influence of both the discount rate and the climatic patterns on optimal harvest strategics. In general, decreases in either the discount rate or in the frequency of favorable weather patterns lcd to a more conservative defoliation policy. This did not hold, however, for plants in states of low vigor. Optimal control for shadscale and winterfat tended to stabilize on a policy of heavy defoliation stress, followed by one or more seasons of rest. Big sagebrush required a policy of heavy summer defoliation when sufficient active shoot material is present at the beginning of the growing season. The comparison of fixed and optimal strategies indicated considerable improvement in defoliation yields when optimal strategies are followed. The superior performance was attributable to increased defoliation of plants in states of high vigor. Improvements were found for both discounted and undiscounted yields.

Learning by strategies and learning by drill--evidence from an fMRI study.

PubMed

Delazer, M; Ischebeck, A; Domahs, F; Zamarian, L; Koppelstaetter, F; Siedentopf, C M; Kaufmann, L; Benke, T; Felber, S

2005-04-15

The present fMRI study investigates, first, whether learning new arithmetic operations is reflected by changing cerebral activation patterns, and second, whether different learning methods lead to differential modifications of brain activation. In a controlled design, subjects were trained over a week on two new complex arithmetic operations, one operation trained by the application of back-up strategies, i.e., a sequence of arithmetic operations, the other by drill, i.e., by learning the association between the operands and the result. In the following fMRI session, new untrained items, items trained by strategy and items trained by drill, were assessed using an event-related design. Untrained items as compared to trained showed large bilateral parietal activations, with the focus of activation along the right intraparietal sulcus. Further foci of activation were found in both inferior frontal gyri. The reverse contrast, trained vs. untrained, showed a more focused activation pattern with activation in both angular gyri. As suggested by the specific activation patterns, newly acquired expertise was implemented in previously existing networks of arithmetic processing and memory. Comparisons between drill and strategy conditions suggest that successful retrieval was associated with different brain activation patterns reflecting the underlying learning methods. While the drill condition more strongly activated medial parietal regions extending to the left angular gyrus, the strategy condition was associated to the activation of the precuneus which may be accounted for by visual imagery in memory retrieval.

Neural and behavioral correlates of selective stopping: Evidence for a different strategy adoption.

PubMed

Sánchez-Carmona, Alberto J; Albert, Jacobo; Hinojosa, José A

2016-10-01

The present study examined the neural and behavioral correlates of selective stopping, a form of inhibition that has scarcely been investigated. The selectivity of the inhibitory process is needed when individuals have to deal with an environment filled with multiple stimuli, some of which require inhibition and some of which do not. The stimulus-selective stop-signal task has been used to explore this issue assuming that all participants interrupt their ongoing responses selectively to stop but not to ignore signals. However, recent behavioral evidence suggests that some individuals do not carry out the task as experimenters expect, since they seemed to interrupt their response non-selectively to both signals. In the present study, we detected and controlled the cognitive strategy adopted by participants (n=57) when they performed a stimulus-selective stop-signal task before comparing brain activation between conditions. In order to determine both the onset and the end of the response cancellation process underlying each strategy and to fully take advantage of the precise temporal resolution of event-related potentials, we used a mass univariate approach. Source localization techniques were also employed to estimate the neural underpinnings of the effects observed at the scalp level. Our results from scalp and source level analysis support the behavioral-based strategy classification. Specific effects were observed depending on the strategy adopted by participants. Thus, when contrasting successful stop versus ignore conditions, increased activation was only evident for subjects who were classified as using a strategy whereby the response interruption process was selective to stop trials. This increased activity was observed during the P3 time window in several left-lateralized brain regions, including middle and inferior frontal gyri, as well as parietal and insular cortices. By contrast, in those participants who used a strategy characterized by stopping non-selectively, no activation differences between successful stop and ignore conditions were observed at the estimated time at which response interruption process occurs. Overall, results from the current study highlight the importance of controlling for the different strategies adopted by participants to perform selective stopping tasks before analyzing brain activation patterns. Copyright © 2016 Elsevier Inc. All rights reserved.

Selection of sustainable seaweed and grouper aquaculture development strategy: a case of Pulau Panjang, Serang Regency Banten Province

NASA Astrophysics Data System (ADS)

Soejarwo, P. A.; Fitriyanny, W. P.; Heriati, A.; Hakim, A. R.

2018-03-01

Due to their high-income contribution, seaweed and grouper aquacultures are important activities in Pulau Panjang community. Determining alternative strategies in developing sustainable aquaculture for seaweed and grouper and their priority factors from theses aquaculture activities are done using TOPSIS and AHP analysis. It was found that the development strategy that must be taken is the option to maintain aquaculture activities, while, environment factor is the highest priority to maintain seaweed and grouper aquaculture in Pulau Panjang. Then three priorities are obtained from environment factor. The first is to maintain the water quality by the growth requirements of seaweed and grouper by encouraging the formation of “Environmental Community Awareness” that involved the active participation of the community to maintain quality and carrying capacity of the environment. Second is to use of natural or artificial coastal protectors (soft structure). The third priority strategy is integration and real implementation of heavy metal pollution control between government, industry sector and society.

Hybrid passive/active damping for robust multivariable acoustic control in composite plates

NASA Astrophysics Data System (ADS)

Veeramani, Sudha; Wereley, Norman M.

1996-05-01

Noise transmission through a flexible kevlar-epoxy composite trim panel into an acoustic cavity or box is studied with the intent of controlling the interior sound fields. A hybrid noise attenuation technique is proposed which uses viscoelastic damping layers in the composite plate for passive attenuation of high frequency noise transmission, and uses piezo-electric patch actuators for active control in the low frequency range. An adaptive feedforward noise control strategy is applied. The passive structural damping augmentation incorporated in the composite plates is also intended to increase stability robustness of the active noise control strategy. A condenser microphone in the interior of the enclosure functions as the error sensor. Three composite plates were experimentally evaluated: one with no damping layer, the second with a 10 mil damping layer, and the third with a 15 mil damping layer. The damping layer was cocured in the kevlar-epoxy trim panels. Damping in the plates was increased from 1.6% for the plate with no damping layer, to 5.9% for the plate with a 15 mil damping layer. In experimental studies, the improved stability robustness of the controller was demonstrated by improved adaptive feedforward control algorithm convergence. A preliminary analytical model is presented that describes the dynamic behavior of a composite panel actuated by piezoelectric actuators bonded to its surface.

Status of E-ELT M5 scale-one demonstrator

NASA Astrophysics Data System (ADS)

Barriga, Pablo; Sedghi, Babak; Dimmler, Martin; Kornweibel, Nick

2014-07-01

The fifth mirror of the European Extremely Large Telescope optical train is a field stabilization tip/tilt unit responsible for correcting the dynamical tip and tilt caused mainly by wind load on the telescope. A scale-one prototype including the inclined support, the fixed frame and a basic control system was designed and manufactured by NTE-SENER (Spain) and CSEM (Switzerland) as part of the prototyping and design activities. All interfaces to the mirror have been reproduced on a dummy structure reproducing the inertial characteristics of the optical element. The M5 unit is required to have sufficient bandwidth for tip/tilt reference commands coming from the wavefront control system. Such a bandwidth can be achieved using local active damping loop to damp the low frequency mechanical modes before closing a position loop. Prototyping on the M5 unit has been undertaken in order to demonstrate the E-ELT control system architecture, concepts and development standards and to further study active damping strategies. The control system consists of two nested loops: a local damping loop and a position loop. The development of this control system was undertaken following the E-ELT control system development standards in order to determine their applicability and performance and includes hardware selection, communication, synchronization, configuration, and data logging. In this paper we present the current status of the prototype M5 control system and the latest results on the active damping control strategy, in particular the promising results obtained with the method of positive position feedback.

A randomized controlled trial of an online, modular, active learning training program for behavioral activation for depression.

PubMed

Puspitasari, Ajeng J; Kanter, Jonathan W; Busch, Andrew M; Leonard, Rachel; Dunsiger, Shira; Cahill, Shawn; Martell, Christopher; Koerner, Kelly

2017-08-01

This randomized-controlled trial assessed the efficacy of a trainer-led, active-learning, modular, online behavioral activation (BA) training program compared with a self-paced online BA training with the same modular content. Seventy-seven graduate students (M = 30.3 years, SD = 6.09; 76.6% female) in mental health training programs were randomly assigned to receive either the trainer-led or self-paced BA training. Both trainings consisted of 4 weekly sessions covering 4 core BA strategies. Primary outcomes were changes in BA skills as measured by an objective role-play assessment and self-reported use of BA strategies. Assessments were conducted at pre-, post-, and 6-weeks after training. A series of longitudinal mixed effect models assessed changes in BA skills and a longitudinal model implemented with generalized estimating equations assessed BA use over time. Significantly greater increases in total BA skills were found in the trainer-led training condition. The trainer-led training condition also showed greater increases in all core BA skills either at posttraining, follow-up, or both. Reported use of BA strategies with actual clients increased significantly from pre- to posttraining and maintained at follow-up in both training conditions. This trial adds to the literature on the efficacy of online training as a method to disseminate BA. Online training with an active learning, modular approach may be a promising and accessible implementation strategy. Additional strategies may need to be paired with the online BA training to assure the long-term implementation and sustainability of BA in clinical practice. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

A Preliminary Investigation of Temperature Dependency of a Shape Memory Actuator with Time-Based Control in Aircraft Interiors

NASA Astrophysics Data System (ADS)

Otibar, Dennis; Weirich, Antonia; Kortenjann, Marcus; Kuhlenkötter, Bernd

2017-06-01

Shape memory alloys (SMA) possess an array of unique functional properties which are influenced by a complex interaction of different factors. Due to thermal sensitivity, slight changes in the environmental temperature may cause the properties to change significantly. This poses a huge challenge especially for the use of SMAs as actuators. The most common and elementary activation strategy of SMA actuators is based on the duration of activation and cooling with constant activation parameters. However, changing environmental influences cause the necessity to modify these parameters. This circumstance needs to be especially considered in the design process of actuator controls. This paper focuses on investigating the influence of environmental temperature changes on time-based activated SMA actuators. The results of the described experiments form the base for designing reactive control strategies for SMA actuators used in alternating environments. An example for application fields with changing environments and particularly changing temperatures are aircraft related implementations. This area also stands to benefit from the actuators’ advantages in ecological efficiency.

Engaging in Rather than Disengaging from Stress: Effective Coping and Perceived Control

PubMed Central

Dijkstra, Maria T. M.; Homan, Astrid C.

2016-01-01

Being able to cope effectively with stress can help people to avoid negative consequences for their psychological well-being. The purpose of this study was to find out why some coping strategies are effective in reducing the negative effect of stressors on well-being and some are not. We argue that the degree to which such coping strategies engage or disengage people from stressful incidents is related to their perceived control of the situation that, in turn, is positively associated with their psychological well-being. We thus propose that the relationship between coping and psychological well-being is mediated by the extent of perceived sense of control. We collected cross-sectional data from a large heterogeneous sample (N = 543) in the Netherlands. We assessed seven different coping strategies, perceived control, and psychological well-being. Our results indeed revealed that strategies reflecting more engaged coping such as active confronting and reassuring thoughts, were associated with more sense of control and therefore to psychological well-being. In contrast, strategies reflecting disengagement coping, such as passive reaction pattern, palliative reaction, and avoidance, were associated with less perceived control, which in turn was negatively associated with psychological well-being. Results regarding the coping strategies expressing emotions and seeking social support were less straightforward, with the former being negatively associated with perceived control and psychological well-being, even though this strategy has stress engaging elements, and the latter only showing a positive indirect effect on psychological well-being via perceived control, but no positive main effect on well-being. These findings are discussed from the perspective of stress being an environment-perception-response process. PMID:27708603

Assembly of Terpenoid Cores by a Simple, Tunable Strategy.

PubMed

Lahtigui, Ouidad; Emmetiere, Fabien; Zhang, Wei; Jirmo, Liban; Toledo-Roy, Samira; Hershberger, John C; Macho, Jocelyn M; Grenning, Alexander J

2016-12-19

Oxygenated, polycyclic terpenoid natural products have important biological activities. Although total synthesis of such terpenes is widely studied, synthetic strategies that allow for controlled placement of oxygen atoms and other functionality remains a challenge. Herein, we present a simple, scalable, and tunable synthetic strategy to assemble terpenoid-like polycycloalkanes from cycloalkanones, malononitrile, and allylic electrophiles, abundantly available reagent classes. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Controlling electrodeposited ultrathin amorphous Fe hydroxides film on V-doped nickel sulfide nanowires as efficient electrocatalyst for water oxidation

NASA Astrophysics Data System (ADS)

Shang, Xiao; Yan, Kai-Li; Lu, Shan-Shan; Dong, Bin; Gao, Wen-Kun; Chi, Jing-Qi; Liu, Zi-Zhang; Chai, Yong-Ming; Liu, Chen-Guang

2017-09-01

Developing cost-effective electrocatalysts with both high activity and stability remains challenging for oxygen evolution reaction (OER) in water electrolysis. Herein, based on V-doped nickel sulfide nanowire on nickel foam (NiVS/NF), we further conduct controllable electrodeposition of Fe hydroxides film on NiVS/NF (eFe/NiVS/NF) to further improve OER performance and stability. For comparison, ultrafast chemical deposition of Fe hydroxides on NiVS/NF (uFe/NiVS/NF) is also utilized. V-doping of NiVS/NF may introduce more active sites for OER, and nanowire structure can expose abundant active sites and facilitate mass transport. Both of the two depositions generate amorphous Fe hydroxides film covering on the surface of nanowires and lead to enhanced OER activities. Furthermore, electrodeposition strategy realizes uniform Fe hydroxides film on eFe/NiVS/NF confirmed by superior OER activity of eFe/NiVS/NF than uFe/NiVS/NF with relatively enhanced stability. The OER activity of eFe/NiVS/NF depends on various electrodepositon time, and the optimal time (15 s) is obtained with maximum OER activity. Therefore, the controllable electrodeposition of Fe may provide an efficient and simple strategy to enhance the OER properties of electrocatalysts.

It's all in the delivery! An analysis of instructional strategies from effective health education curricula.

PubMed

Herbert, Patrick C; Lohrmann, David K

2011-05-01

This study explores the relationship between instructional strategies and effective health education curricula. A content analysis of 10 health education curricula was conducted to determine if they include common instructional strategies for actively engaging students in acquisition of health skills. To be included, the curricula had to (1) be research-based and proven via empirical testing to positively influence the health behaviors and (2) address 1 of Centers for Disease Control and Prevention's 6 priority health risk behaviors. Content analysis revealed 5 active learning strategies incorporated to involve students in acquiring health skills. Role play, group cooperation, and small group discussion were found in all 10 curricula. To a lesser extent, interactive technology and team games were also included. When combined with previous research regarding the characteristics of effective teachers, it becomes clear that effective health education is delivered by teachers who employ a wide repertoire of active learning strategies while devoting substantial instructional time to those specific strategies that involve students in skills practice. © 2011, American School Health Association.

Neural circuits of emotion regulation: a comparison of mindfulness-based and cognitive reappraisal strategies.

PubMed

Opialla, Sarah; Lutz, Jacqueline; Scherpiet, Sigrid; Hittmeyer, Anna; Jäncke, Lutz; Rufer, Michael; Grosse Holtforth, Martin; Herwig, Uwe; Brühl, Annette B

2015-02-01

Dealing with one's emotions is a core skill in everyday life. Effective cognitive control strategies have been shown to be neurobiologically represented in prefrontal structures regulating limbic regions. In addition to cognitive strategies, mindfulness-associated methods are increasingly applied in psychotherapy. We compared the neurobiological mechanisms of these two strategies, i.e. cognitive reappraisal and mindfulness, during both the cued expectation and perception of negative and potentially negative emotional pictures. Fifty-three healthy participants were examined with functional magnetic resonance imaging (47 participants included in analysis). Twenty-four subjects applied mindfulness, 23 used cognitive reappraisal. On the neurofunctional level, both strategies were associated with comparable activity of the medial prefrontal cortex and the amygdala. When expecting negative versus neutral stimuli, the mindfulness group showed stronger activations in ventro- and dorsolateral prefrontal cortex, supramarginal gyrus as well as in the left insula. During the perception of negative versus neutral stimuli, the two groups only differed in an increased activity in the caudate in the cognitive group. Altogether, both strategies recruited overlapping brain regions known to be involved in emotion regulation. This result suggests that common neural circuits are involved in the emotion regulation by mindfulness-based and cognitive reappraisal strategies. Identifying differential activations being associated with the two strategies in this study might be one step towards a better understanding of differential mechanisms of change underlying frequently used psychotherapeutic interventions.

Systematic Review of the Effectiveness of Occupational Therapy–Related Interventions for People With Parkinson’s Disease

PubMed Central

Foster, Erin R.; Bedekar, Mayuri

2014-01-01

We describe the results of a systematic review of the literature on occupational therapy–related interventions for people with Parkinson’s disease (PD). Three broad categories of intervention emerged: (1) exercise or physical activity; (2) environmental cues, stimuli, and objects; and (3) self-management and cognitive–behavioral strategies. Moderate to strong evidence exists for task-specific benefits of targeted physical activity training on motor performance, postural stability, and balance. Low to moderate evidence indicates that more complex, multimodal activity training supports improvement in functional movement activities. The evidence is moderate that the use of external supports during functional mobility or other movement activities has positive effects on motor control. In addition, moderate evidence is available that individualized interventions focused on promoting participant wellness initiatives and personal control by means of cognitive–behavioral strategies can improve targeted areas of quality of life. The implications for practice, education, and research are discussed. PMID:24367954

Modification of insulin sensitivity and glycemic control by activity and exercise.

PubMed

Roberts, Christian K; Little, Jonathan P; Thyfault, John P

2013-10-01

Type 2 diabetes has progressed into a major contributor to preventable death, and developing optimal therapeutic strategies to prevent future type 2 diabetes and its primary clinical manifestation of cardiovascular disease is a major public health challenge. This article will provide a brief overview of the role of activity and exercise in modulating insulin sensitivity and will outline the effect of physical activity, high-intensity interval training, and resistance training on insulin sensitivity and glycemic control.

Active Control of Cryogenic Propellants in Space

NASA Technical Reports Server (NTRS)

Notardonato, William

2011-01-01

A new era of space exploration is being planned. Exploration architectures under consideration require the long term storage of cryogenic propellants in space. This requires development of active control systems to mitigate the effect of heat leak. This work summarizes current state of the art, proposes operational design strategies and presents options for future architectures. Scaling and integration of active systems will be estimated. Ideal long range spacecraft systems will be proposed with Exploration architecture benefits considered.

A pragmatic examination of active and passive recruitment methods to improve the reach of community lifestyle programs: The Talking Health Trial.

PubMed

Estabrooks, Paul; You, Wen; Hedrick, Valisa; Reinholt, Margaret; Dohm, Erin; Zoellner, Jamie

2017-01-19

A primary challenge for behavior change strategies is ensuring that interventions can be effective while also attracting a broad and representative sample of the target population. The purpose of this case-study was to report on (1) the reach of a randomized controlled trial targeting reduced sugary beverages, (2) potential participant characteristic differences based on active versus passive recruitment strategies, and (3) recruitment strategy cost. Demographic and recruitment information was obtained for 8 counties and for individuals screened for participation. Personnel activities and time were tracked. Costs were calculated and compared by active versus passive recruitment. Six-hundred and twenty, of 1,056 screened, individuals were eligible and 301enrolled (77% women; 90% white; mean income $21,981 ± 16,443). Eighty-two and 44% of those responding to passive and active methods, respectively, enrolled in the trial. However, active recruitment strategies yielded considerably more enrolled (active = 199; passive = 102) individuals. Passive recruitment strategies yielded a less representative sample in terms of gender (more women), education (higher), and income (higher; p's <0.05). The average cost of an actively recruited and enrolled participant was $278 compared to $117 for a passively recruited and enrolled participant. Though passive recruitment is more cost efficient it may reduce the reach of sugary drink reduction strategies in lower educated and economic residents in rural communities. Clinicaltrials.gov; ID: NCT02193009 , July 2014, retrospectively registered.

Active structural control for damping augmentation and compensation of thermal distortion

NASA Technical Reports Server (NTRS)

Sirlin, S. W.

1992-01-01

A large space-based Focus Mission Interferometer is used as a testbed for the NASA Controls and Structures Interaction Program. Impedance-based adaptive structural control and control of thermal disturbances are demonstrated using an end-to-end simulation of the system's optical performance. Attention is also given to integrated optical/structural modeling and a hierarchical, layered control strategy.

Reinforcement learning for stabilizing an inverted pendulum naturally leads to intermittent feedback control as in human quiet standing.

PubMed

Michimoto, Kenjiro; Suzuki, Yasuyuki; Kiyono, Ken; Kobayashi, Yasushi; Morasso, Pietro; Nomura, Taishin

2016-08-01

Intermittent feedback control for stabilizing human upright stance is a promising strategy, alternative to the standard time-continuous stiffness control. Here we show that such an intermittent controller can be established naturally through reinforcement learning. To this end, we used a single inverted pendulum model of the upright posture and a very simple reward function that gives a certain amount of punishments when the inverted pendulum falls or changes its position in the state space. We found that the acquired feedback controller exhibits hallmarks of the intermittent feedback control strategy, namely the action of the feedback controller is switched-off intermittently when the state of the pendulum is located near the stable manifold of the unstable saddle-type upright equilibrium of the inverted pendulum with no active control: this action provides an opportunity to exploit transiently converging dynamics toward the unstable upright position with no help of the active feedback control. We then speculate about a possible physiological mechanism of such reinforcement learning, and suggest that it may be related to the neural activity in the pedunculopontine tegmental nucleus (PPN) of the brainstem. This hypothesis is supported by recent evidence indicating that PPN might play critical roles for generation and regulation of postural tonus, reward prediction, as well as postural instability in patients with Parkinson's disease.

A Vehicle Active Safety Model: Vehicle Speed Control Based on Driver Vigilance Detection Using Wearable EEG and Sparse Representation.

PubMed

Zhang, Zutao; Luo, Dianyuan; Rasim, Yagubov; Li, Yanjun; Meng, Guanjun; Xu, Jian; Wang, Chunbai

2016-02-19

In this paper, we present a vehicle active safety model for vehicle speed control based on driver vigilance detection using low-cost, comfortable, wearable electroencephalographic (EEG) sensors and sparse representation. The proposed system consists of three main steps, namely wireless wearable EEG collection, driver vigilance detection, and vehicle speed control strategy. First of all, a homemade low-cost comfortable wearable brain-computer interface (BCI) system with eight channels is designed for collecting the driver's EEG signal. Second, wavelet de-noising and down-sample algorithms are utilized to enhance the quality of EEG data, and Fast Fourier Transformation (FFT) is adopted to extract the EEG power spectrum density (PSD). In this step, sparse representation classification combined with k-singular value decomposition (KSVD) is firstly introduced in PSD to estimate the driver's vigilance level. Finally, a novel safety strategy of vehicle speed control, which controls the electronic throttle opening and automatic braking after driver fatigue detection using the above method, is presented to avoid serious collisions and traffic accidents. The simulation and practical testing results demonstrate the feasibility of the vehicle active safety model.

A Vehicle Active Safety Model: Vehicle Speed Control Based on Driver Vigilance Detection Using Wearable EEG and Sparse Representation

PubMed Central

Zhang, Zutao; Luo, Dianyuan; Rasim, Yagubov; Li, Yanjun; Meng, Guanjun; Xu, Jian; Wang, Chunbai

2016-01-01

In this paper, we present a vehicle active safety model for vehicle speed control based on driver vigilance detection using low-cost, comfortable, wearable electroencephalographic (EEG) sensors and sparse representation. The proposed system consists of three main steps, namely wireless wearable EEG collection, driver vigilance detection, and vehicle speed control strategy. First of all, a homemade low-cost comfortable wearable brain-computer interface (BCI) system with eight channels is designed for collecting the driver’s EEG signal. Second, wavelet de-noising and down-sample algorithms are utilized to enhance the quality of EEG data, and Fast Fourier Transformation (FFT) is adopted to extract the EEG power spectrum density (PSD). In this step, sparse representation classification combined with k-singular value decomposition (KSVD) is firstly introduced in PSD to estimate the driver’s vigilance level . Finally, a novel safety strategy of vehicle speed control, which controls the electronic throttle opening and automatic braking after driver fatigue detection using the above method, is presented to avoid serious collisions and traffic accidents. The simulation and practical testing results demonstrate the feasibility of the vehicle active safety model. PMID:26907278

Determinants of sport-specific postural control strategy and balance performance of amateur rugby players.

PubMed

Chow, Gary C C; Fong, Shirley S M; Chung, Joanne W Y; Chung, Louisa M Y; Ma, Ada W W; Macfarlane, Duncan J

2016-11-01

Postural control strategy and balance performance of rugby players are important yet under-examined issues. This study aimed to examine the differences in balance strategy and balance performance between amateur rugby players and non-players, and to explore training- and injury-related factors that may affect rugby players' balance outcomes. Cross-sectional and exploratory study. Forty-five amateur rugby players and 41 healthy active individuals participated in the study. Balance performance and balance strategies were assessed using the sensory organization test (SOT) of the Smart Equitest computerized dynamic posturography machine. Rugby training history and injury history were solicited from the participants. The SOT strategy scores were 1.99-54.90% lower in the rugby group than in the control group (p<0.05), and the equilibrium scores were 1.06-14.29% lower in the rugby group than in the control group (p<0.05). After accounting for age, sex and body mass index, only length of rugby training (in years) was independently associated with the SOT condition 6 strategy score, explaining 15.7% of its variance (p=0.006). There was no association between SOT condition 6 strategy/equilibrium scores and injury history among the rugby players (p>0.05). Amateur rugby players demonstrated inferior balance strategy and balance performance compared to their non-training counterparts. Their suboptimal balance strategy was associated with insufficient training experience but not with history of injury. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Adolescents' Physical Activity and Sedentary Behavior: A Pathway in Reducing Overweight and Obesity. The PRALIMAP 2-Year Cluster Randomized Controlled Trial.

PubMed

Omorou, Abdou Y; Langlois, Johanne; Lecomte, Edith; Vuillemin, Anne; Briançon, Serge

2015-05-01

explaining why and how overweight prevention programs were effective was a real need; especially the potential role of physical activity (PA) and sedentary behavior (SB) should be highlighted. This study aimed to evaluate the 2-year effectiveness of a screening and care strategy in adolescents' weight reduction with regards to PA and SB change. 1745 adolescents aged 15.1 years from PRALIMAP trial was included (n = 840 for screening and care group and n = 905 for control group). PA and SB time (international physical activity questionnaire: IPAQ), body mass index (BMI), and BMI z-score were assessed at inclusion and after 2-year intervention. Hierarchical mixed models were applied. Compared with the control group, screening and care strategy was associated with an increase in global PA (58 min/week), a moderate PA (43 min/week), the adherence to the French PA guidelines (OR = 1.3), and a decrease in SB (-198 min/week). The 2-year weight change decreased when adjusted for PA and SB suggesting that the effect of screening and care strategy was partly mediated by PA and SB. Screening and care intervention seemed to be effective in increasing PA and decreasing SB. The induced PA and SB modifications contributed to the observed weight change.

Cell-Mediated Immunity to Target the Persistent Human Immunodeficiency Virus Reservoir.

PubMed

Riley, James L; Montaner, Luis J

2017-03-15

Effective clearance of virally infected cells requires the sequential activity of innate and adaptive immunity effectors. In human immunodeficiency virus (HIV) infection, naturally induced cell-mediated immune responses rarely eradicate infection. However, optimized immune responses could potentially be leveraged in HIV cure efforts if epitope escape and lack of sustained effector memory responses were to be addressed. Here we review leading HIV cure strategies that harness cell-mediated control against HIV in stably suppressed antiretroviral-treated subjects. We focus on strategies that may maximize target recognition and eradication by the sequential activation of a reconstituted immune system, together with delivery of optimal T-cell responses that can eliminate the reservoir and serve as means to maintain control of HIV spread in the absence of antiretroviral therapy (ART). As evidenced by the evolution of ART, we argue that a combination of immune-based strategies will be a superior path to cell-mediated HIV control and eradication. Available data from several human pilot trials already identify target strategies that may maximize antiviral pressure by joining innate and engineered T cell responses toward testing for sustained HIV remission and/or cure. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Synergies and strategies underlying normal and vestibulary deficient control of balance: implication for neuroprosthetic control.

PubMed

Allum, J H; Honegger, F

1993-01-01

Future developments of neuroprosthetic control will probably permit locomotion and posture to be maintained without the aid of crutches and will therefore require some form of balance control. Three fundamental questions will arise. First, the question of the location of imbalance-sensing transducers must be assessed. Secondly, the synergy, which is the relative amplitude and timing of muscle activity, and/or the strategy of joint torques required to re-establish a stable posture for different types of balance disturbances must be addressed. Thirdly, the control laws that map either trunk muscle activity or imbalance-sensing transducer outputs into multi-joint postural control of standing by paraplegic individuals must be generated. The most appropriate means of gathering the relevant information applicable to neuroprosthetic control systems is through the detailed analysis of normal and non-normal human models. In order to gain such detailed insights into normal balance control and its dependence on head angular and linear accelerations, the synergy and strategy of balance corrections in normal subjects or patients with vestibular deficits were investigated for two types of support surface perturbation, a dorsiflexion rotation (ROT) and a rearward translation (TRANS). These experimentally induced perturbations to upright stance were adjusted to cause equal amplitudes of ankle dorsiflexion, thus providing additional information about the role of lower leg proprioception on balance control. Synergies defined on the basis of peak cross-correlations of each recorded muscle's EMG to that of the largest muscle response were significantly different for TRANS and ROT. Translation synergies consisted of a sequential coactivation at several levels (soleus and abdominals some 30 msec before hamstrings, and trapezius some 15 msec before paraspinals), whereas the sequential activation of paraspinals and tibialis anterior dominated the balance synergy to ROT. Likewise, response strategies, defined using cross-correlations of joint torques, differed. That for TRANS was organised as a multi-link strategy with neck torques leading those of all other joints by 40 msec or more; hip joint lead ankle torques by 30 msec. That for ROT was organised around hip and ankle torques without a major correlation to neck torques. Vestibulary deficient subjects developed weaker synergies with respect to subjects with normal balance systems under eyes-open conditions and there was no clear synergy with eyes closed. Consequently, hip torques were delayed some 180 msec with respect to ankle torques, and correlations to neck torques were completely out of phase under eyes-closed conditions. Fundamental changes in TRANS synergies and strategies also occurred in vestibulary deficient subjects for eyes-open and eyes-closed conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

Task constraints and minimization of muscle effort result in a small number of muscle synergies during gait.

PubMed

De Groote, Friedl; Jonkers, Ilse; Duysens, Jacques

2014-01-01

Finding muscle activity generating a given motion is a redundant problem, since there are many more muscles than degrees of freedom. The control strategies determining muscle recruitment from a redundant set are still poorly understood. One theory of motor control suggests that motion is produced through activating a small number of muscle synergies, i.e., muscle groups that are activated in a fixed ratio by a single input signal. Because of the reduced number of input signals, synergy-based control is low dimensional. But a major criticism on the theory of synergy-based control of muscles is that muscle synergies might reflect task constraints rather than a neural control strategy. Another theory of motor control suggests that muscles are recruited by optimizing performance. Optimization of performance has been widely used to calculate muscle recruitment underlying a given motion while assuming independent recruitment of muscles. If synergies indeed determine muscle recruitment underlying a given motion, optimization approaches that do not model synergy-based control could result in muscle activations that do not show the synergistic muscle action observed through electromyography (EMG). If, however, synergistic muscle action results from performance optimization and task constraints (joint kinematics and external forces), such optimization approaches are expected to result in low-dimensional synergistic muscle activations that are similar to EMG-based synergies. We calculated muscle recruitment underlying experimentally measured gait patterns by optimizing performance assuming independent recruitment of muscles. We found that the muscle activations calculated without any reference to synergies can be accurately explained by on average four synergies. These synergies are similar to EMG-based synergies. We therefore conclude that task constraints and performance optimization explain synergistic muscle recruitment from a redundant set of muscles.

A cluster randomized controlled trial of strategies to increase adolescents' physical activity and motivation in physical education: results of the Motivating Active Learning in Physical Education (MALP) trial.

PubMed

Lonsdale, Chris; Rosenkranz, Richard R; Sanders, Taren; Peralta, Louisa R; Bennie, Andrew; Jackson, Ben; Taylor, Ian M; Lubans, David R

2013-11-01

Physical education (PE) programs aim to promote physical activity (PA) and reach most school-aged youth. However, PA levels within PE lessons are often low. In this cluster-randomized controlled trial, we examined the effects of three self-determination theory-based motivational strategies on PA and sedentary behavior, as well as their hypothesized antecedents during PE lessons. Data were collected in Sydney, Australia (October-December 2011). After baseline testing, teachers (n=16) and their classes (n=288 students; M=13.6 years, 50.4% male) were randomly assigned to one of four teaching strategy conditions: (1) explaining relevance; (2) providing choice; (3) complete free choice; or (4) usual practice. Teachers then delivered the assigned strategy. Primary outcomes were accelerometer-assessed PA and student motivation during lessons. Secondary outcomes included sedentary behavior, perceptions of teachers' support and psychological needs satisfaction. The 'free choice' intervention increased PA (p<.05). 'Providing choice' and 'free choice' interventions decreased sedentary behavior (p<.05). The interventions did not influence motivation, but students' autonomy increased during both choice-based interventions (p<.05). Promoting choice can produce short-term increases in PA and decreases in sedentary behavior, as well as increased perceived autonomy during PE lessons. © 2013.

Coping with Disaster: The Case of Israeli Adolescents under Threat of Missile Attack.

ERIC Educational Resources Information Center

Zeidner, Moshe

1993-01-01

Studied the relationships of coping resources, optimism, perceived control, and coping strategies to anxiety, physical symptoms, and cognitive functioning for 69 male and 40 female Jewish Israeli adolescents in real crisis during the Persian Gulf War. Discusses the implications of the reported mixture of active and palliative coping strategies.…

Identifying and Evaluating the Therapeutic Strategies Used During a Manualized Self- Advocacy Intervention for Transition-Age Youth.

PubMed

Kramer, Jessica M

2015-01-01

Prior to undertaking randomized control trials, pilot research should ensure that an intervention's active ingredients are operationalized in manuals or protocols. This study identified the strategies facilitators reported to use during the implementation of a problem-solving self-advocacy intervention, Project "Teens making Environment and Activity Modifications" (TEAM), with transition-age youth with developmental disabilities, and evaluated the alignment of strategies with the intervention's hypothesized mechanisms of change. An iterative process was used to conduct a content analysis of 106 field notes completed by six facilitators. Facilitators used 19 strategies. Findings suggest that facilitators used strategies simultaneously to ensure universal design for learning, maximize relevance for individual trainees, and maintain a safe and encouraging environment. Facilitators can individualize Project TEAM in a way that operationalizes the mechanisms of change underlying Project TEAM. The quality of the intervention may improve by explicitly incorporating these strategies into the intervention protocol. The strategies may also be applicable to therapists implementing interventions informed, by similar theoretical propositions.

Increased alertness, better than posture prioritization, explains dual-task performance in prosthesis users and controls under increasing postural and cognitive challenge.

PubMed

Howard, Charla L; Perry, Bonnie; Chow, John W; Wallace, Chris; Stokic, Dobrivoje S

2017-11-01

Sensorimotor impairments after limb amputation impose a threat to stability. Commonly described strategies for maintaining stability are the posture first strategy (prioritization of balance) and posture second strategy (prioritization of concurrent tasks). The existence of these strategies was examined in 13 below-knee prosthesis users and 15 controls during dual-task standing under increasing postural and cognitive challenge by evaluating path length, 95% sway area, and anterior-posterior and medial-lateral amplitudes of the center of pressure. The subjects stood on two force platforms under usual (hard surface/eyes open) and difficult (soft surface/eyes closed) conditions, first alone and while performing a cognitive task without and then with instruction on cognitive prioritization. During standing alone, sway was not significantly different between groups. After adding the cognitive task without prioritization instruction, prosthesis users increased sway more under the dual-task than single-task standing (p ≤ 0.028) during both usual and difficult conditions, favoring the posture second strategy. Controls, however, reduced dual-task sway under a greater postural challenge (p ≤ 0.017), suggesting the posture first strategy. With prioritization of the cognitive task, sway was unchanged or reduced in prosthesis users, suggesting departure from the posture second strategy, whereas controls maintained the posture first strategy. Individual analysis of dual tasking revealed that greater postural demand in controls and greater cognitive challenge in prosthesis users led to both reduced sway and improved cognitive performance, suggesting cognitive-motor facilitation. Thus, activation of additional resources through increased alertness, rather than posture prioritization, may explain dual-task performance in both prosthesis users and controls under increasing postural and cognitive challenge.

ODECS -- A computer code for the optimal design of S.I. engine control strategies

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

Arsie, I.; Pianese, C.; Rizzo, G.

1996-09-01

The computer code ODECS (Optimal Design of Engine Control Strategies) for the design of Spark Ignition engine control strategies is presented. This code has been developed starting from the author`s activity in this field, availing of some original contributions about engine stochastic optimization and dynamical models. This code has a modular structure and is composed of a user interface for the definition, the execution and the analysis of different computations performed with 4 independent modules. These modules allow the following calculations: (1) definition of the engine mathematical model from steady-state experimental data; (2) engine cycle test trajectory corresponding to amore » vehicle transient simulation test such as ECE15 or FTP drive test schedule; (3) evaluation of the optimal engine control maps with a steady-state approach; (4) engine dynamic cycle simulation and optimization of static control maps and/or dynamic compensation strategies, taking into account dynamical effects due to the unsteady fluxes of air and fuel and the influences of combustion chamber wall thermal inertia on fuel consumption and emissions. Moreover, in the last two modules it is possible to account for errors generated by a non-deterministic behavior of sensors and actuators and the related influences on global engine performances, and compute robust strategies, less sensitive to stochastic effects. In the paper the four models are described together with significant results corresponding to the simulation and the calculation of optimal control strategies for dynamic transient tests.« less

Learning to Control Advanced Life Support Systems

NASA Technical Reports Server (NTRS)

Subramanian, Devika

2004-01-01

Advanced life support systems have many interacting processes and limited resources. Controlling and optimizing advanced life support systems presents unique challenges. In particular, advanced life support systems are nonlinear coupled dynamical systems and it is difficult for humans to take all interactions into account to design an effective control strategy. In this project. we developed several reinforcement learning controllers that actively explore the space of possible control strategies, guided by rewards from a user specified long term objective function. We evaluated these controllers using a discrete event simulation of an advanced life support system. This simulation, called BioSim, designed by Nasa scientists David Kortenkamp and Scott Bell has multiple, interacting life support modules including crew, food production, air revitalization, water recovery, solid waste incineration and power. They are implemented in a consumer/producer relationship in which certain modules produce resources that are consumed by other modules. Stores hold resources between modules. Control of this simulation is via adjusting flows of resources between modules and into/out of stores. We developed adaptive algorithms that control the flow of resources in BioSim. Our learning algorithms discovered several ingenious strategies for maximizing mission length by controlling the air and water recycling systems as well as crop planting schedules. By exploiting non-linearities in the overall system dynamics, the learned controllers easily out- performed controllers written by human experts. In sum, we accomplished three goals. We (1) developed foundations for learning models of coupled dynamical systems by active exploration of the state space, (2) developed and tested algorithms that learn to efficiently control air and water recycling processes as well as crop scheduling in Biosim, and (3) developed an understanding of the role machine learning in designing control systems for advanced life support.

Optimal detection and control strategies for invasive species management

Treesearch

Shefali V. Mehta; Robert G. Haight; Frances R. Homans; Stephen Polasky; Robert C. Venette

2007-01-01

The increasing economic and environmental losses caused by non-native invasive species amplify the value of identifying and implementing optimal management options to prevent, detect, and control invasive species. Previous literature has focused largely on preventing introductions of invasive species and post-detection control activities; few have addressed the role of...

Enhanced power quality based single phase photovoltaic distributed generation system

NASA Astrophysics Data System (ADS)

Panda, Aurobinda; Pathak, M. K.; Srivastava, S. P.

2016-08-01

This article presents a novel control strategy for a 1-ϕ 2-level grid-tie photovoltaic (PV) inverter to enhance the power quality (PQ) of a PV distributed generation (PVDG) system. The objective is to obtain the maximum benefits from the grid-tie PV inverter by introducing current harmonics as well as reactive power compensation schemes in its control strategy, thereby controlling the PV inverter to achieve multiple functions in the PVDG system such as: (1) active power flow control between the PV inverter and the grid, (2) reactive power compensation, and (3) grid current harmonics compensation. A PQ enhancement controller (PQEC) has been designed to achieve the aforementioned objectives. The issue of underutilisation of the PV inverter in nighttime has also been addressed in this article and for the optimal use of the system; the PV inverter is used as a shunt active power filter in nighttime. A prototype model of the proposed system is developed in the laboratory, to validate the effectiveness of the control scheme, and is tested with the help of the dSPACE DS1104 platform.

Controlling lymphatic filariasis and soil-transmitted helminthiasis together in South Asia: opportunities and challenges

PubMed Central

Padmasiri, EA; Montresor, A; Biswas, G; de Silva, NR

2017-01-01

Summary Lymphatic filariasis (LF) and the major soil-transmitted helminth (STH) infections are co-endemic in many countries, particularly in Asia. Control strategies for both groups of infections have increasingly focused on the use of mass chemotherapy. With the use of albendazole, there is now a tool that is common to both. However, there are also important differences in their modes of transmission and epidemiology, and as a result, in the overall control strategies. The Global Programme for the Elimination of Lymphatic Filariasis aims to eliminate LF through time-limited, Mass Drug Administration programmes. STH control activities are more diffuse, aiming to piggy-back de-worming onto existing services such as school health activities; controlling morbidity, rather than eliminating infection, is the stated goal. In order to maximize health benefits to communities that are endemic for one or both of these infections, it is vitally important that policy makers and programme managers have a clear understanding of both commonalities and differences, and implement control programmes that allocate available resources in an optimal manner. PMID:16546228

Levels-of-processing effects in first-degree relatives of individuals with schizophrenia.

PubMed

Bonner-Jackson, Aaron; Csernansky, John G; Barch, Deanna M

2007-05-15

First-degree relatives of individuals with schizophrenia show cognitive impairments that are similar to but less severe than their ill relatives. We have shown that memory impairments can be improved and prefrontal cortical (PFC) activity increased in individuals with schizophrenia by providing beneficial encoding strategies. The current study used a similar paradigm to determine whether siblings of individuals with schizophrenia (SIBs) also show increases in brain activity when presented with beneficial encoding strategies. Twenty-one SIBs and 38 siblings of healthy comparison subjects underwent functional magnetic resonance imaging scans while engaged in deep (abstract/concrete judgments) and shallow (orthographic judgments) encoding. Subjects were then given a recognition memory test. The groups did not differ on encoding or recognition accuracy, and the SIBs benefited from deep encoding to a similar degree as control subjects. The SIBs showed deep encoding-related activity in a number of PFC regions typically activated during semantic processing. However, SIBs showed more activity than control subjects in three subregions of PFC (left BA 44 & BA 47 bilaterally). Siblings of individuals with schizophrenia benefit from supportive verbal encoding conditions. Like individuals with schizophrenia, SIBs also show increased task-related activity in a larger number of PFC subregions than control subjects during deep verbal encoding.

Active model-based balancing strategy for self-reconfigurable batteries

NASA Astrophysics Data System (ADS)

Bouchhima, Nejmeddine; Schnierle, Marc; Schulte, Sascha; Birke, Kai Peter

2016-08-01

This paper describes a novel balancing strategy for self-reconfigurable batteries where the discharge and charge rates of each cell can be controlled. While much effort has been focused on improving the hardware architecture of self-reconfigurable batteries, energy equalization algorithms have not been systematically optimized in terms of maximizing the efficiency of the balancing system. Our approach includes aspects of such optimization theory. We develop a balancing strategy for optimal control of the discharge rate of battery cells. We first formulate the cell balancing as a nonlinear optimal control problem, which is modeled afterward as a network program. Using dynamic programming techniques and MATLAB's vectorization feature, we solve the optimal control problem by generating the optimal battery operation policy for a given drive cycle. The simulation results show that the proposed strategy efficiently balances the cells over the life of the battery, an obvious advantage that is absent in the other conventional approaches. Our algorithm is shown to be robust when tested against different influencing parameters varying over wide spectrum on different drive cycles. Furthermore, due to the little computation time and the proved low sensitivity to the inaccurate power predictions, our strategy can be integrated in a real-time system.

Mind your "smoking manners": the tobacco industry tactics to normalize smoking in Japan.

PubMed

Kashiwabara, Mina; Armada, Francisco

2013-11-09

The tobacco industry has adapted its promotional strategies as tobacco-control measures have increased. This paper describes the tobacco industry's strategies on smoking manners and illustrates how these interfere with tobacco-control policy in Japan where tobacco control remains weak. Information on the tobacco industry's promotional strategies in Japan was collected through direct observation, a review of tobacco industry documents and a literature review. The limitation of the study would be a lack of industry documents from Japan as we relied on a database of a U.S. institution to collect internal documents from the tobacco industry. Japan Tobacco began using the manners strategies in the early 1960s. Collaborating with wide range of actors -including local governments and companies- the tobacco industry has promoted smoking manners to wider audiences through its advertising and corporate social responsibility activities. The tobacco industry in Japan has taken advantage of the cultural value placed on manners in Japan to increase the social acceptability of smoking, eventually aiming to diminish public support for smoke-free policies that threatens the industry's business. A stronger enforcement of the WHO Framework Convention on Tobacco Control is critical to counteracting such strategies.

Predicting the Impact of Intervention Strategies for Sleeping Sickness in Two High-Endemicity Health Zones of the Democratic Republic of Congo.

PubMed

Rock, Kat S; Torr, Steve J; Lumbala, Crispin; Keeling, Matt J

2017-01-01

Two goals have been set for Gambian human African trypanosomiasis (HAT), the first is to achieve elimination as a public health problem in 90% of foci by 2020, and the second is to achieve zero transmission globally by 2030. It remains unclear if certain HAT hotspots could achieve elimination as a public health problem by 2020 and, of greater concern, it appears that current interventions to control HAT in these areas may not be sufficient to achieve zero transmission by 2030. A mathematical model of disease dynamics was used to assess the potential impact of changing the intervention strategy in two high-endemicity health zones of Kwilu province, Democratic Republic of Congo. Six key strategies and twelve variations were considered which covered a range of recruitment strategies for screening and vector control. It was found that effectiveness of HAT screening could be improved by increasing effort to recruit high-risk groups for screening. Furthermore, seven proposed strategies which included vector control were predicted to be sufficient to achieve an incidence of less than 1 reported case per 10,000 people by 2020 in the study region. All vector control strategies simulated reduced transmission enough to meet the 2030 goal, even if vector control was only moderately effective (60% tsetse population reduction). At this level of control the full elimination threshold was expected to be met within six years following the start of the change in strategy and over 6000 additional cases would be averted between 2017 and 2030 compared to current screening alone. It is recommended that a two-pronged strategy including both enhanced active screening and tsetse control is implemented in this region and in other persistent HAT foci to ensure the success of the control programme and meet the 2030 elimination goal for HAT.

Predicting the Impact of Intervention Strategies for Sleeping Sickness in Two High-Endemicity Health Zones of the Democratic Republic of Congo

PubMed Central

Torr, Steve J.; Lumbala, Crispin; Keeling, Matt J.

2017-01-01

Two goals have been set for Gambian human African trypanosomiasis (HAT), the first is to achieve elimination as a public health problem in 90% of foci by 2020, and the second is to achieve zero transmission globally by 2030. It remains unclear if certain HAT hotspots could achieve elimination as a public health problem by 2020 and, of greater concern, it appears that current interventions to control HAT in these areas may not be sufficient to achieve zero transmission by 2030. A mathematical model of disease dynamics was used to assess the potential impact of changing the intervention strategy in two high-endemicity health zones of Kwilu province, Democratic Republic of Congo. Six key strategies and twelve variations were considered which covered a range of recruitment strategies for screening and vector control. It was found that effectiveness of HAT screening could be improved by increasing effort to recruit high-risk groups for screening. Furthermore, seven proposed strategies which included vector control were predicted to be sufficient to achieve an incidence of less than 1 reported case per 10,000 people by 2020 in the study region. All vector control strategies simulated reduced transmission enough to meet the 2030 goal, even if vector control was only moderately effective (60% tsetse population reduction). At this level of control the full elimination threshold was expected to be met within six years following the start of the change in strategy and over 6000 additional cases would be averted between 2017 and 2030 compared to current screening alone. It is recommended that a two-pronged strategy including both enhanced active screening and tsetse control is implemented in this region and in other persistent HAT foci to ensure the success of the control programme and meet the 2030 elimination goal for HAT. PMID:28056016

Control of constraint forces and trajectories in a rich sensory and actuation environment.

PubMed

Hemami, Hooshang; Dariush, Behzad

2010-12-01

A simple control strategy is proposed and applied to a class of non-linear systems that have abundant sensory and actuation channels as in living systems. The main objective is the independent control of constrained trajectories of motion, and control of the corresponding constraint forces. The peripheral controller is a proportional, derivative and integral (PID) controller. A central controller produces, via pattern generators, reference signals that are the desired constrained position and velocity trajectories, and the desired constraint forces. The basic tenet of the this hybrid control strategy is the use of two mechanisms: 1. linear state and force feedback, and 2. non-linear constraint velocity feedback - sliding mode feedback. The first mechanism can be envisioned as a high gain feedback systems. The high gain attribute imitates the agonist-antagonist co-activation in natural systems. The strategy is applied to the control of the force and trajectory of a two-segment thigh-leg planar biped leg with a mass-less foot cranking a pedal that is analogous to a bicycle pedal. Five computational experiments are presented to show the effectiveness of the strategy and the performance of the controller. The findings of this paper are applicable to the design of orthoses and prostheses to supplement functional electrical stimulation for support purposes in the spinally injured cases. Copyright © 2010 Elsevier Inc. All rights reserved.

Processes in arithmetic strategy selection: a fMRI study.

PubMed

Taillan, Julien; Ardiale, Eléonore; Anton, Jean-Luc; Nazarian, Bruno; Félician, Olivier; Lemaire, Patrick

2015-01-01

This neuroimaging (functional magnetic resonance imaging) study investigated neural correlates of strategy selection. Young adults performed an arithmetic task in two different conditions. In both conditions, participants had to provide estimates of two-digit multiplication problems like 54 × 78. In the choice condition, participants had to select the better of two available rounding strategies, rounding-up (RU) strategy (i.e., doing 60 × 80 = 4,800) or rounding-down (RD) strategy (i.e., doing 50 × 70 = 3,500 to estimate product of 54 × 78). In the no-choice condition, participants did not have to select strategy on each problem but were told which strategy to use; they executed RU and RD strategies each on a series of problems. Participants also had a control task (i.e., providing correct products of multiplication problems like 40 × 50). Brain activations and performance were analyzed as a function of these conditions. Participants were able to frequently choose the better strategy in the choice condition; they were also slower when they executed the difficult RU than the easier RD. Neuroimaging data showed greater brain activations in right anterior cingulate cortex (ACC), dorso-lateral prefrontal cortex (DLPFC), and angular gyrus (ANG), when selecting (relative to executing) the better strategy on each problem. Moreover, RU was associated with more parietal cortex activation than RD. These results suggest an important role of fronto-parietal network in strategy selection and have important implications for our further understanding and modeling cognitive processes underlying strategy selection.

Processes in arithmetic strategy selection: a fMRI study

PubMed Central

Taillan, Julien; Ardiale, Eléonore; Anton, Jean-Luc; Nazarian, Bruno; Félician, Olivier; Lemaire, Patrick

2015-01-01

This neuroimaging (functional magnetic resonance imaging) study investigated neural correlates of strategy selection. Young adults performed an arithmetic task in two different conditions. In both conditions, participants had to provide estimates of two-digit multiplication problems like 54 × 78. In the choice condition, participants had to select the better of two available rounding strategies, rounding-up (RU) strategy (i.e., doing 60 × 80 = 4,800) or rounding-down (RD) strategy (i.e., doing 50 × 70 = 3,500 to estimate product of 54 × 78). In the no-choice condition, participants did not have to select strategy on each problem but were told which strategy to use; they executed RU and RD strategies each on a series of problems. Participants also had a control task (i.e., providing correct products of multiplication problems like 40 × 50). Brain activations and performance were analyzed as a function of these conditions. Participants were able to frequently choose the better strategy in the choice condition; they were also slower when they executed the difficult RU than the easier RD. Neuroimaging data showed greater brain activations in right anterior cingulate cortex (ACC), dorso-lateral prefrontal cortex (DLPFC), and angular gyrus (ANG), when selecting (relative to executing) the better strategy on each problem. Moreover, RU was associated with more parietal cortex activation than RD. These results suggest an important role of fronto-parietal network in strategy selection and have important implications for our further understanding and modeling cognitive processes underlying strategy selection. PMID:25698995

Worksite physical activity policies and environments in relation to employee physical activity.

PubMed

Crespo, Noe C; Sallis, James F; Conway, Terry L; Saelens, Brian E; Frank, Lawrence D

2011-01-01

Examine associations between worksite physical activity promotion strategies and employees' physical activity and sedentary behaviors. Cross-sectional. Seattle-King County, Washington and Baltimore, Maryland-Washington, D.C. regions. Adults working outside the home (n = 1313). Mean age was 45 ± 10 years, 75.8% of participants were non-Hispanic white, 56% were male, and 51% had income ≥$70,000/year. Participants reported demographic characteristics and presence/absence of nine physical activity promotion environment and policy strategies in their work environment (e.g., showers, lockers, physical activity programs). A worksite physical activity promotion index was a tally of strategies. Total sedentary and moderate-to-vigorous physical activity (MVPA) min/d were objectively assessed via 7-day accelerometry. Total job-related physical activity minutes and recreational physical activity minutes were self-reported with the International Physical Activity Questionnaire. Mixed-effects models and generalized estimating equations evaluated the association of the worksite promotion index with physical activity and sedentary behavior, adjusting for demographics. A higher worksite promotion index was significantly associated with higher total sedentary behavior (β = 3.97), MVPA (β = 1.04), recreational physical activity (β = 1.1 and odds ratio = 1.39; away from work and at work, respectively) and negatively with job-related physical activity (β = .90). Multiple worksite physical activity promotion strategies based on environmental supports and policies may increase recreational physical activity and should be evaluated in controlled trials. These findings are particularly important given the increasingly sedentary nature of employment.

Strategies of performance self-monitoring in automotive production.

PubMed

Faye, Hélène; Falzon, Pierre

2009-09-01

Production in the automotive industry, based on assembly line work, is now characterized by lean manufacturing and customization. This results in greater flexibility and increased quality demands, including worker performance self-monitoring. The objectives of this study are to refine the concept of performance self-monitoring and to characterize the strategies developed by operators to achieve it. Data were collected based on the method of individual auto-confrontation, consisting of two steps: eleven assembly-line operators of a French automotive company were individually observed and video-taped while they were working; an interview then allowed each operator to discuss his/her activity based on the video-tape. This study expands the concept of performance self-monitoring by highlighting three types of strategies directly oriented toward quality: prevention, feedback control and control action strategies.

Functional Based Adaptive and Fuzzy Sliding Controller for Non-Autonomous Active Suspension System

NASA Astrophysics Data System (ADS)

Huang, Shiuh-Jer; Chen, Hung-Yi

In this paper, an adaptive sliding controller is developed for controlling a vehicle active suspension system. The functional approximation technique is employed to substitute the unknown non-autonomous functions of the suspension system and release the model-based requirement of sliding mode control algorithm. In order to improve the control performance and reduce the implementation problem, a fuzzy strategy with online learning ability is added to compensate the functional approximation error. The update laws of the functional approximation coefficients and the fuzzy tuning parameters are derived from the Lyapunov theorem to guarantee the system stability. The proposed controller is implemented on a quarter-car hydraulic actuating active suspension system test-rig. The experimental results show that the proposed controller suppresses the oscillation amplitude of the suspension system effectively.

Dynamic Changes in Amygdala Activation and Functional Connectivity in Children and Adolescents with Anxiety Disorders

PubMed Central

Swartz, Johnna R.; Phan, K. Luan; Angstadt, Mike; Fitzgerald, Kate D.; Monk, Christopher S.

2015-01-01

Anxiety disorders are associated with abnormalities in amygdala function and prefrontal cortex-amygdala connectivity. The majority of fMRI studies have examined mean group differences in amygdala activation or connectivity in children and adolescents with anxiety disorders relative to controls, but emerging evidence suggests that abnormalities in amygdala function are dependent on the timing of the task and may vary across the course of a scanning session. The goal of the present study was to extend our knowledge of the dynamics of amygdala dysfunction by examining whether changes in amygdala activation and connectivity over scanning differ in pediatric anxiety disorder patients relative to typically developing controls during an emotion processing task. Examining changes in activation over time allows for a comparison of how brain function differs during initial exposure to novel stimuli versus more prolonged exposure. Participants included 34 anxiety disorder patients and 19 controls 7 to 19 years old. Participants performed an emotional face matching task during fMRI scanning and the task was divided into thirds in order to examine change in activation over time. Results demonstrated that patients exhibited an abnormal pattern of amygdala activation characterized by an initially heightened amygdala response relative to controls at the beginning of scanning, followed by significant decreases in activation over time. In addition, controls evidenced greater prefrontal cortex-amygdala connectivity during the beginning of scanning relative to patients. These results indicate that differences in emotion processing between the groups vary from initial exposure to novel stimuli relative to more prolonged exposure. Implications are discussed regarding how this pattern of neural activation may relate to altered early-occurring or anticipatory emotion-regulation strategies and maladaptive later-occurring strategies in children and adolescents with anxiety disorders. PMID:25422963

Physical activity and adolescents: an exploratory randomized controlled trial investigating the influence of affective and instrumental text messages.

PubMed

Sirriyeh, Reema; Lawton, Rebecca; Ward, Jane

2010-11-01

The present study attempts to develop and pilot the feasibility and efficacy of a novel intervention using affective messages as a strategy to increase physical activity (PA) levels in adolescents. Design An exploratory pilot randomized control trial was used to compare behaviour change over 2 weeks. A modified form of the International Physical Activity Questionnaire was used to assess PA behaviour. A total of 120 adolescents (16-19 years) from 4 sixth forms in West Yorkshire completed the field-based study. Participants were randomly assigned to one of three experimental conditions, or the control condition (N=28). Participants in experimental conditions received 1 short messaging service (SMS) text message per day over the 2 weeks, which included manipulations of either affective beliefs (enjoyable/unenjoyable; N=31), instrumental beliefs (beneficial/harmful; N=30), or a combination of these (N=31). Control participants received one SMS text message per week. Outcomes were measured at baseline and at the end of the 2 week intervention. PA levels increased by the equivalent of 31.5  minutes of moderate (four metabolic equivalent) activity per week during the study. Main effects of condition (p=.049), and current physical activity level (p=.002) were identified, along with a significant interaction between condition and current activity level (p=.006). However, when the sample was split at baseline into active and inactive participants, a main effect of condition remained for inactive participants only (p=.001). Post hoc analysis revealed that inactive participants who received messages targeting affective beliefs increased their activity levels significantly more than the instrumental (p=.012), combined (p=.002), and control groups (p=.018). Strategies based on affective associations may be more effective for increasing PA levels in inactive individuals.

CATS-based Air Traffic Controller Agents

NASA Technical Reports Server (NTRS)

Callantine, Todd J.

2002-01-01

This report describes intelligent agents that function as air traffic controllers. Each agent controls traffic in a single sector in real time; agents controlling traffic in adjoining sectors can coordinate to manage an arrival flow across a given meter fix. The purpose of this research is threefold. First, it seeks to study the design of agents for controlling complex systems. In particular, it investigates agent planning and reactive control functionality in a dynamic environment in which a variety perceptual and decision making skills play a central role. It examines how heuristic rules can be applied to model planning and decision making skills, rather than attempting to apply optimization methods. Thus, the research attempts to develop intelligent agents that provide an approximation of human air traffic controller behavior that, while not based on an explicit cognitive model, does produce task performance consistent with the way human air traffic controllers operate. Second, this research sought to extend previous research on using the Crew Activity Tracking System (CATS) as the basis for intelligent agents. The agents use a high-level model of air traffic controller activities to structure the control task. To execute an activity in the CATS model, according to the current task context, the agents reference a 'skill library' and 'control rules' that in turn execute the pattern recognition, planning, and decision-making required to perform the activity. Applying the skills enables the agents to modify their representation of the current control situation (i.e., the 'flick' or 'picture'). The updated representation supports the next activity in a cycle of action that, taken as a whole, simulates air traffic controller behavior. A third, practical motivation for this research is to use intelligent agents to support evaluation of new air traffic control (ATC) methods to support new Air Traffic Management (ATM) concepts. Current approaches that use large, human-in-the-loop simulations are unquestionably valuable for this purpose, but pose considerable logistical, fiscal, and experimental control problems. First, data analysis is extremely complicated, owing simply to the large number of participants and data sources in such simulations. In addition, experienced human air traffic controllers working adjacent sectors tend to flexibly adapt to the evolving control problem - potentially shifting to other strategies than those under investigation. In addition, their performance is tightly coupled to the control interface, which in the development phase may support some concepts and supporting strategies better than others. A simple shift in strategy by one controller can change the character of a particular traffic scenario dramatically, which makes experimental comparison of ATC performance under different traffic scenarios difficult. Training a given team of controllers on operations under a new ATM concept for a sufficient period of time could avert such difficulties, but instituting an adequate training program is expensive and logistically difficult.

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

NASA Astrophysics Data System (ADS)

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

2017-04-01

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

Robust control of drag and lateral dynamic response for road vehicles exposed to cross-wind gusts

NASA Astrophysics Data System (ADS)

Pfeiffer, Jens; King, Rudibert

2018-03-01

A robust closed-loop active flow control strategy for road vehicles under unsteady cross-wind conditions is presented. It is designed based on black-box models identified from experimental data for a 3D bluff body equipped with Coanda actuators along the rear edges. The controller adjusts the blowing rates of the actuators individually, achieving a drag reduction of about 15% while simultaneously improving cross-wind sensitivity. Hereby, the lateral vehicle dynamics and driver behavior are taken into account and replicated in the wind tunnel via a novel model support system. The effectiveness of the control strategy is demonstrated via cross-wind gust experiments.

Striatal dysfunction during reversal learning in unmedicated schizophrenia patients☆

PubMed Central

Schlagenhauf, Florian; Huys, Quentin J.M.; Deserno, Lorenz; Rapp, Michael A.; Beck, Anne; Heinze, Hans-Joachim; Dolan, Ray; Heinz, Andreas

2014-01-01

Subjects with schizophrenia are impaired at reinforcement-driven reversal learning from as early as their first episode. The neurobiological basis of this deficit is unknown. We obtained behavioral and fMRI data in 24 unmedicated, primarily first episode, schizophrenia patients and 24 age-, IQ- and gender-matched healthy controls during a reversal learning task. We supplemented our fMRI analysis, focusing on learning from prediction errors, with detailed computational modeling to probe task solving strategy including an ability to deploy an internal goal directed model of the task. Patients displayed reduced functional activation in the ventral striatum (VS) elicited by prediction errors. However, modeling task performance revealed that a subgroup did not adjust their behavior according to an accurate internal model of the task structure, and these were also the more severely psychotic patients. In patients who could adapt their behavior, as well as in controls, task solving was best described by cognitive strategies according to a Hidden Markov Model. When we compared patients and controls who acted according to this strategy, patients still displayed a significant reduction in VS activation elicited by informative errors that precede salient changes of behavior (reversals). Thus, our study shows that VS dysfunction in schizophrenia patients during reward-related reversal learning remains a core deficit even when controlling for task solving strategies. This result highlights VS dysfunction is tightly linked to a reward-related reversal learning deficit in early, unmedicated schizophrenia patients. PMID:24291614

Effects of a multifactorial injury prevention intervention in physical education teachers: A randomized controlled trial.

PubMed

Vercruysse, Sien; Haerens, Leen; Verhagen, Evert; Goossens, Lennert; De Clercq, Dirk

2016-10-01

Physical education (PE) teachers are at a high risk of musculoskeletal sports or work-related injuries because of the physical activity as inherent part of their profession. Such injuries have a negative impact on work and leisure time activities, and effective injury prevention interventions are needed. The present study aimed at testing the effectiveness of an injury prevention intervention that was developed and optimized according to PE teachers' wishes and values. Fifty-five PE teachers were randomly assigned to intervention or control group. Intervention group teachers engaged in two days of training during which they familiarized with eight injury prevention strategies (seven intrinsic and one extrinsic). A special feature of the intervention was that the way of delivery was based on the self-determination theory in order to stimulate participants' motivation to adhere to the proposed strategies. Prospective registrations during one school year were conducted concerning injuries and preventive behaviours. Results showed that the intervention group teachers had a lower number of injuries per 1000 h time of exposure (TOE) than the controls (INT: 0.49, CON: 1.14 injuries/1000 h TOE, OR: 2.32, 95% CI: 1.06-5.07), and applied a broader variety of strategies including dynamic and static stretching, core stability, balance and strength training, when compared to the controls who mainly engaged in warming-up. In conclusion, with the same amount of time, an injury reduction was found in PE teachers through a more balanced use of provided preventive strategies.

Persistence of improvements in postural strategies following motor control training in people with recurrent low back pain.

PubMed

Tsao, Henry; Hodges, Paul W

2008-08-01

This study investigated long-term effects of training on postural control using the model of deficits in activation of transversus abdominis (TrA) in people with recurrent low back pain (LBP). Nine volunteers with LBP attended four sessions for assessment and/or training (initial, two weeks, four weeks and six months). Training of repeated isolated voluntary TrA contractions were performed at the initial and two-week session with feedback from real-time ultrasound imaging. Home program involved training twice daily for four weeks. Electromyographic activity (EMG) of trunk and deltoid muscles was recorded with surface and fine-wire electrodes. Rapid arm movement and walking were performed at each session, and immediately after training on the first two sessions. Onset of trunk muscle activation relative to prime mover deltoid during arm movements, and the coefficient of variation (CV) of EMG during averaged gait cycle were calculated. Over four weeks of training, onset of TrA EMG was earlier during arm movements and CV of TrA EMG was reduced (consistent with more sustained EMG activity). Changes were retained at six months follow-up (p<0.05). These results show persistence of motor control changes following training and demonstrate that this training approach leads to motor learning of automatic postural control strategies.

Psychosocial Factors of Different Health Behaviour Patterns in Adolescents: Association with Overweight and Weight Control Behaviours

PubMed Central

Veloso, Susana M.; Matos, Margarida G.; Carvalho, Marina; Diniz, José A.

2012-01-01

Physical activity, nutrition, and sedentary behaviour combine to influence the risk of overweight among adolescents. This paper aims to identify psychosocial factors of different health behaviour patterns in adolescents and its association with overweight and weight control behaviours. The 3069 adolescents of both genders (average of 14.8 years old) from the 2010 Portuguese survey of Health Behaviour School-Aged Children (HBSC) answered the 2010 HBSC self-reported questionnaire. It used the cluster k-means (nonhierarchy method), qui-square, one-way ANOVA, and logistic regression. Three clusters with different behavioural patterns (physical activity, sedentary, and eating) composed the results obtained. The sedentary group (34%) had lower self-regulation, body satisfaction, health and wellness, family and classmates relationships, communication with the father than the other two groups. The active gamers (25%) had a smaller BMI but used more unhealthy weight control strategies than the other two groups. The healthy group (41%) was more motivated and more satisfied with school but was not different than the active gamers in most psychosocial variables. Differences were found between clusters for weight control behaviours and psychosocial variables. Different strategies for different patterns were necessary in order to promote obesity prevention and, simultaneously, target healthy lifestyle and wellbeing in adolescents. PMID:22811890

Active Control of Inlet Noise on the JT15D Turbofan Engine

NASA Technical Reports Server (NTRS)

Smith, Jerome P.; Hutcheson, Florence V.; Burdisso, Ricardo A.; Fuller, Chris R.

1999-01-01

This report presents the key results obtained by the Vibration and Acoustics Laboratories at Virginia Tech over the year from November 1997 to December 1998 on the Active Noise Control of Turbofan Engines research project funded by NASA Langley Research Center. The concept of implementing active noise control techniques with fuselage-mounted error sensors is investigated both analytically and experimentally. The analytical part of the project involves the continued development of an advanced modeling technique to provide prediction and design guidelines for application of active noise control techniques to large, realistic high bypass engines of the type on which active control methods are expected to be applied. Results from the advanced analytical model are presented that show the effectiveness of the control strategies, and the analytical results presented for fuselage error sensors show good agreement with the experimentally observed results and provide additional insight into the control phenomena. Additional analytical results are presented for active noise control used in conjunction with a wavenumber sensing technique. The experimental work is carried out on a running JT15D turbofan jet engine in a test stand at Virginia Tech. The control strategy used in these tests was the feedforward Filtered-X LMS algorithm. The control inputs were supplied by single and multiple circumferential arrays of acoustic sources equipped with neodymium iron cobalt magnets mounted upstream of the fan. The reference signal was obtained from an inlet mounted eddy current probe. The error signals were obtained from a number of pressure transducers flush-mounted in a simulated fuselage section mounted in the engine test cell. The active control methods are investigated when implemented with the control sources embedded within the acoustically absorptive material on a passively-lined inlet. The experimental results show that the combination of active control techniques with fuselage-mounted error sensors and passive control techniques is an effective means of reducing radiated noise from turbofan engines. Strategic selection of the location of the error transducers is shown to be effective for reducing the radiation towards particular directions in the farfield. An analytical model is used to predict the behavior of the control system and to guide the experimental design configurations, and the analytical results presented show good agreement with the experimentally observed results.

Hospital management of outpatient oncology treatment decisions: a survey to identify strategies and concerns.

PubMed

Li, Edward; Schleif, Ron; Edelen, Bruce

2013-09-01

Historically, hospitals did not actively restrict or manage outpatient oncology drug use, because treatment options were few, and reimbursement was generous. Recent growth of novel agents coupled with reimbursement challenges may require a strategy change. The extent of hospital engagement in controlling outpatient oncology drug use is currently unknown. Our objective was to describe the extent of hospital outpatient oncology drug management, management strategies employed, and specific drugs/tumor types of most concern for inappropriate use and cost. A multiple choice-question survey assessed management strategies and the drugs/tumors of greatest concern in US hospitals that dispense outpatient chemotherapy. From June to July 2011, the survey was distributed electronically to members of the Hematology-Oncology Pharmacy Association, representing 281 institutions. The survey was completed by 93 respondents (33% institutional response rate). Most institutions (99%) use at least one form of control to manage outpatient oncology drug therapy; 89% establish preferred therapies, and most use a multidisciplinary management team consisting of oncologists, pharmacists, nurses, and other practitioners. Tumor types of most concern for inappropriate drug use and cost were: prostate, breast, non-small-cell lung, melanoma, and colorectal. Fifty-five percent were concerned about drugs used in supportive care management. Drugs most restricted were: cetuximab, bevacizumab, eribulin, panitumumab, and trastuzumab. There is active control, management, and restriction of outpatient oncology drugs by hospitals. A majority of these institutions use a multidisciplinary team with active involvement by an oncologist. Future evaluations of hospital programs should consider monitoring the evolution of how institutions manage outpatient oncology services.

Whole-organism screening for gluconeogenesis identifies activators of fasting metabolism

PubMed Central

Gut, Philipp; Baeza-Raja, Bernat; Andersson, Olov; Hasenkamp, Laura; Hsiao, Joseph; Hesselson, Daniel; Akassoglou, Katerina; Verdin, Eric; Hirschey, Matthew D.; Stainier, Didier Y.R.

2012-01-01

Improving the control of energy homeostasis can lower cardiovascular risk in metabolically compromised individuals. To identify new regulators of whole-body energy control, we conducted a high-throughput screen in transgenic reporter zebrafish for small molecules that modulate the expression of the fasting-inducible gluconeogenic gene pck1. We show that this in vivo strategy identified several drugs that impact gluconeogenesis in humans, as well as metabolically uncharacterized compounds. Most notably, we find that the Translocator Protein (TSPO) ligands PK 11195 and Ro5-4864 are glucose lowering agents despite a strong inductive effect on pck1 expression. We show that these drugs are activators of a fasting-like energy state, and importantly that they protect high-fat diet induced obese mice from hepatosteatosis and glucose intolerance, two pathological manifestations of metabolic dysregulation. Thus, using a whole-organism screening strategy, this study has identified new small molecule activators of fasting metabolism. PMID:23201900

Meta-analysis of studies on chemical, physical and biological agents in the control of Aedes aegypti.

PubMed

Lima, Estelita Pereira; Goulart, Marília Oliveira Fonseca; Rolim Neto, Modesto Leite

2015-09-04

Aedes aegypti is a vector of international concern because it can transmit to humans three important arboviral diseases: yellow fever, dengue and chikungunya. Epidemics that are repeated year after year in a variety of urban centers indicate that there are control failures, allowing the vector to continue expanding. To identify the most effective vector control strategies and the factors that contributed to the success or failure of each strategy, we carried out a systematic review with meta-analysis of articles published in 12 databases, from 1974 to the month of December 2013. We evaluated the association between the use of whatever chemical substance, mechanical agent, biological or integrated actions against A. aegypti and the control of the vector, as measured by 10 indicators. We found 2,791 articles, but after careful selection, only 26 studies remained for analysis related to control interventions implemented in 15 countries, with 5 biological, 5 chemical, 3 mechanical and 13 integrated strategies. The comparison among all of them, indicated that the control of A. aegypti is significantly associated with the type of strategy used, and that integrated interventions consist of the most effective method for controlling A. aegypti. The most effective control method was the integrated approach, considering the influence of eco-bio-social determinants in the virus-vector-man epidemiological chain, and community involvement, starting with community empowerment as active agents of vector control.

Dual-mode disturbance-accommodating pointing controller for Hubble Space Telescope

NASA Astrophysics Data System (ADS)

Addington, Stewart I.; Johnson, C. D.

1995-03-01

Cyclic thermal expansions and mechanical stiction effects in the solar arrays on the Hubble Space Telescope (HST) are triggering repeated occurrences of damped, relaxation-type flex-body vibrations of the solar arrays. Those solar array vibrations are, in turn, causing unwanted deviations of the telescope from its specified pointing direction. In this paper we propose two strategies one can adopt in designing a telescope-pointing controller to cope with the aforementioned disturbances: 1) a total isolation (TI) control strategy whereby the HST controller torques are designed to adaptively counteract and cancel out the persistent disturbing torques that are causing the unwanted telescope motions and 2) an array damping (AD) control strategy whereby the HST controller torques are used to actively augment the natural dampening of the solar array vibrations and the attendant telescope motions, between triggerings of the stiction-related flex-body relaxation oscillations. Using the principles of disturbance accommodation control theory, a dual-mode controller for a generic, planar-motion (single-axis) model of the HST is proposed. This controller incorporates both the TI and AD modes of disturbance accommodation. Simulation studies of the closed-loop system using generic parameter values clearly indicate, qualitatively, the enhanced pointing performance such a controller can achieve.

Active multilayered capsules for in vivo bone formation

PubMed Central

Facca, S.; Cortez, C.; Mendoza-Palomares, C.; Messadeq, N.; Dierich, A.; Johnston, A. P. R.; Mainard, D.; Voegel, J.-C.; Caruso, F.; Benkirane-Jessel, N.

2010-01-01

Interest in the development of new sources of transplantable materials for the treatment of injury or disease has led to the convergence of tissue engineering with stem cell technology. Bone and joint disorders are expected to benefit from this new technology because of the low self-regenerating capacity of bone matrix secreting cells. Herein, the differentiation of stem cells to bone cells using active multilayered capsules is presented. The capsules are composed of poly-L-glutamic acid and poly-L-lysine with active growth factors embedded into the multilayered film. The bone induction from these active capsules incubated with embryonic stem cells was demonstrated in vitro. Herein, we report the unique demonstration of a multilayered capsule-based delivery system for inducing bone formation in vivo. This strategy is an alternative approach for in vivo bone formation. Strategies using simple chemistry to control complex biological processes would be particularly powerful, as they make production of therapeutic materials simpler and more easily controlled. PMID:20160118

Weight maintenance, behaviors and barriers among previous participants of a university-based weight control program.

PubMed

Befort, C A; Stewart, E E; Smith, B K; Gibson, C A; Sullivan, D K; Donnelly, J E

2008-03-01

To examine weight loss maintenance among previous participants of a university-based behavioral weight management program and to compare behavioral strategies and perceived barriers between successful and unsuccessful maintainers. Previous program participants (n=179) completed mailed surveys assessing current weight, weight control behaviors and perceived barriers to weight loss maintenance. At 14.1+/-10.8 months following completion of treatment, survey respondents were on average 12.6+/-12.6 kg, or 11.3+/-10.7%, below baseline weight; 76.5% of respondents had successfully maintained weight, defined as maintaining a weight loss of at least 5% below baseline. Compared to unsuccessful maintainers, successful maintainers reported practicing four dietary and three physical activity weight control strategies more often and experiencing five barriers to healthy eating and exercise less often. After accounting for time since treatment and maximum weight loss while in treatment, the strongest correlates of successful weight loss maintenance were frequent exercise and perceived difficulty of weight management. Clinically meaningful weight loss maintenance was achieved by the majority of participants. Findings support the literature indicating that physical activity is one of the strongest predictors of successful weight loss maintenance. Findings also suggest that strategies to reduce the level of perceived effort required for long-term weight control may improve maintenance outcomes.

Strategies to improve energy efficiency in sewage treatment plants

NASA Astrophysics Data System (ADS)

Au, Mau Teng; Pasupuleti, Jagadeesh; Chua, Kok Hua

2013-06-01

This paper discusses on strategies to improve energy efficiency in Sewage Treatment Plant (STP). Four types of STP; conventional activated sludge, extended aeration, oxidation ditch, and sequence batch reactor are presented and strategized to reduce energy consumption based on their influent flow. Strategies to reduce energy consumption include the use of energy saving devices, energy efficient motors, automation/control and modification of processes. It is envisaged that 20-30% of energy could be saved from these initiatives.

Ask, speak up, and be proactive: Empowering patient infection control to prevent health care-acquired infections.

PubMed

Seale, Holly; Chughtai, Abrar A; Kaur, Rajneesh; Crowe, Philip; Phillipson, Lyn; Novytska, Yuliya; Travaglia, Joanne

2015-05-01

Over the last decade, there has been a slow shift toward the more active engagement of patients and families in preventing health care-associated infections (HCAIs). This pilot study aimed to examine the receptiveness of hospital patients toward a new empowerment tool aimed at increasing awareness and engagement of patients in preventing HCAI. Patients from the surgical department were recruited and randomized into 2 groups: active and control. Patients in the active arm were given an empowerment tool, whereas control patients continued with normal practices. Pre- and postsurveys were administered. At the baseline survey, just over half of the participants were highly willing to assist with infection control strategies. Participants were significantly more likely to be willing to ask a doctor or nurse a factual question then a challenging question. After discharge, 23 of the 60 patients reported discussing a health concern with a staff member; however, only 3 participants asked a staff member to wash their hands. Our results suggest that patients would like to be more informed about HCAIs and are willing to engage with staff members to assist with the prevention of infections while in the hospital setting. Further work is going to need to be undertaken to ascertain the best strategies to promote engagement and participation in infection control activities. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

A semi-active control suspension system for railway vehicles with magnetorheological fluid dampers

NASA Astrophysics Data System (ADS)

Wei, Xiukun; Zhu, Ming; Jia, Limin

2016-07-01

The high-speed train has achieved great progress in the last decades. It is one of the most important modes of transportation between cities. With the rapid development of the high-speed train, its safety issue is paid much more attention than ever before. To improve the stability of the vehicle with high speed, extra dampers (i.e. anti-hunting damper) are used in the traditional bogies with passive suspension system. However, the curving performance of the vehicle is undermined due to the extra lateral force generated by the dampers. The active suspension systems proposed in the last decades attempt to solve the vehicle steering issue. However, the active suspension systems need extra actuators driven by electrical power or hydraulic power. There are some implementation and even safety issues which are not easy to be overcome. In this paper, an innovative semi-active controlled lateral suspension system for railway vehicles is proposed. Four magnetorheological fluid dampers are fixed to the primary suspension system of each bogie. They are controlled by online controllers for enhancing the running stability on the straight track line on the one hand and further improving the curving performance by controlling the damper force on the other hand. Two control strategies are proposed in the light of the pure rolling concept. The effectiveness of the proposed strategies is demonstrated by SIMPACK and Matlab co-simulation for a full railway vehicle with two conventional bogies.

Double-well dynamics of noise-driven control activation in human intermittent control: the case of stick balancing.

PubMed

Zgonnikov, Arkady; Lubashevsky, Ihor

2015-11-01

When facing a task of balancing a dynamic system near an unstable equilibrium, humans often adopt intermittent control strategy: Instead of continuously controlling the system, they repeatedly switch the control on and off. Paradigmatic example of such a task is stick balancing. Despite the simplicity of the task itself, the complexity of human intermittent control dynamics in stick balancing still puzzles researchers in motor control. Here we attempt to model one of the key mechanisms of human intermittent control, control activation, using as an example the task of overdamped stick balancing. In doing so, we focus on the concept of noise-driven activation, a more general alternative to the conventional threshold-driven activation. We describe control activation as a random walk in an energy potential, which changes in response to the state of the controlled system. By way of numerical simulations, we show that the developed model captures the core properties of human control activation observed previously in the experiments on overdamped stick balancing. Our results demonstrate that the double-well potential model provides tractable mathematical description of human control activation at least in the considered task and suggest that the adopted approach can potentially aid in understanding human intermittent control in more complex processes.

Uncertainty and sensitivity analysis of control strategies using the benchmark simulation model No1 (BSM1).

PubMed

Flores-Alsina, Xavier; Rodriguez-Roda, Ignasi; Sin, Gürkan; Gernaey, Krist V

2009-01-01

The objective of this paper is to perform an uncertainty and sensitivity analysis of the predictions of the Benchmark Simulation Model (BSM) No. 1, when comparing four activated sludge control strategies. The Monte Carlo simulation technique is used to evaluate the uncertainty in the BSM1 predictions, considering the ASM1 bio-kinetic parameters and influent fractions as input uncertainties while the Effluent Quality Index (EQI) and the Operating Cost Index (OCI) are focused on as model outputs. The resulting Monte Carlo simulations are presented using descriptive statistics indicating the degree of uncertainty in the predicted EQI and OCI. Next, the Standard Regression Coefficients (SRC) method is used for sensitivity analysis to identify which input parameters influence the uncertainty in the EQI predictions the most. The results show that control strategies including an ammonium (S(NH)) controller reduce uncertainty in both overall pollution removal and effluent total Kjeldahl nitrogen. Also, control strategies with an external carbon source reduce the effluent nitrate (S(NO)) uncertainty increasing both their economical cost and variability as a trade-off. Finally, the maximum specific autotrophic growth rate (micro(A)) causes most of the variance in the effluent for all the evaluated control strategies. The influence of denitrification related parameters, e.g. eta(g) (anoxic growth rate correction factor) and eta(h) (anoxic hydrolysis rate correction factor), becomes less important when a S(NO) controller manipulating an external carbon source addition is implemented.

Contribution from motor unit firing adaptations and muscle co-activation during fatigue.

PubMed

Contessa, Paola; Letizi, John; De Luca, Gianluca; Kline, Joshua C

2018-03-14

The control of motor unit firing behavior during fatigue is still debated in the literature. Most studies agree that the central nervous system increases the excitation to the motoneuron pool to compensate for decreased force contributions of individual motor units and sustain muscle force output during fatigue. However, some studies claim that motor units may decrease their firing rates despite increased excitation, contradicting the direct relationship between firing rates and excitation that governs the voluntary control of motor units. To investigate whether the control of motor units in fact changes with fatigue, we measured motor unit firing behavior during repeated contractions of the first dorsal interosseous (FDI) muscle while concurrently monitoring the activation of surrounding muscles - including the flexor carpi radialis, extensor carpi radialis, and pronator teres. Across all subjects, we observed an overall increase in FDI activation and motor unit firing rates by the end of the fatigue task. However, in some subjects we observed increases in FDI activation and motor unit firing rates only during the initial phase of the fatigue task, followed by subsequent decreases during the late phase of the fatigue task while the co-activation of surrounding muscles increased. These findings indicate that the strategy for sustaining force output may occasionally change leading to increases in the relative activation of surrounding muscles while the excitation to the fatiguing muscle decreases. Importantly, irrespective of changes in the strategy for sustaining force output, the control properties regulating motor unit firing behavior remain unchanged during fatigue.

Finite element based model predictive control for active vibration suppression of a one-link flexible manipulator.

PubMed

Dubay, Rickey; Hassan, Marwan; Li, Chunying; Charest, Meaghan

2014-09-01

This paper presents a unique approach for active vibration control of a one-link flexible manipulator. The method combines a finite element model of the manipulator and an advanced model predictive controller to suppress vibration at its tip. This hybrid methodology improves significantly over the standard application of a predictive controller for vibration control. The finite element model used in place of standard modelling in the control algorithm provides a more accurate prediction of dynamic behavior, resulting in enhanced control. Closed loop control experiments were performed using the flexible manipulator, instrumented with strain gauges and piezoelectric actuators. In all instances, experimental and simulation results demonstrate that the finite element based predictive controller provides improved active vibration suppression in comparison with using a standard predictive control strategy. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Investing in youth tobacco control: a review of smoking prevention and control strategies.

PubMed

Lantz, P M; Jacobson, P D; Warner, K E; Wasserman, J; Pollack, H A; Berson, J; Ahlstrom, A

2000-03-01

To provide a comprehensive review of interventions and policies aimed at reducing youth cigarette smoking in the United States, including strategies that have undergone evaluation and emerging innovations that have not yet been assessed for efficacy. Medline literature searches, books, reports, electronic list servers, and interviews with tobacco control advocates. Interventions and policy approaches that have been assessed or evaluated were categorised using a typology with seven categories (school based, community interventions, mass media/public education, advertising restrictions, youth access restrictions, tobacco excise taxes, and direct restrictions on smoking). Novel and largely untested interventions were described using nine categories. Youth smoking prevention and control efforts have had mixed results. However, this review suggests a number of prevention strategies that are promising, especially if conducted in a coordinated way to take advantage of potential synergies across interventions. Several types of strategies warrant additional attention and evaluation, including aggressive media campaigns, teen smoking cessation programmes, social environment changes, community interventions, and increasing cigarette prices. A significant proportion of the resources obtained from the recent settlement between 46 US states and the tobacco industry should be devoted to expanding, improving and evaluating "youth centred" tobacco prevention and control activities.

Application of a pilot control banding tool for risk level assessment and control of nanoparticle exposures.

PubMed

Paik, Samuel Y; Zalk, David M; Swuste, Paul

2008-08-01

Control banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents that are found in the workplace in the absence of firm toxicological and exposure data. These strategies may be particularly useful in nanotechnology applications, considering the overwhelming level of uncertainty over what nanomaterials and nanotechnologies present as potential work-related health risks, what about these materials might lead to adverse toxicological activity, how risk related to these might be assessed and how to manage these issues in the absence of this information. This study introduces a pilot CB tool or 'CB Nanotool' that was developed specifically for characterizing the health aspects of working with engineered nanoparticles and determining the level of risk and associated controls for five ongoing nanotechnology-related operations being conducted at two Department of Energy research laboratories. Based on the application of the CB Nanotool, four of the five operations evaluated in this study were found to have implemented controls consistent with what was recommended by the CB Nanotool, with one operation even exceeding the required controls for that activity. The one remaining operation was determined to require an upgrade in controls. By developing this dynamic CB Nanotool within the realm of the scientific information available, this application of CB appears to be a useful approach for assessing the risk of nanomaterial operations, providing recommendations for appropriate engineering controls and facilitating the allocation of resources to the activities that most need them.

Cost-performance analysis of nutrient removal in a full-scale oxidation ditch process based on kinetic modeling.

PubMed

Li, Zheng; Qi, Rong; Wang, Bo; Zou, Zhe; Wei, Guohong; Yang, Min

2013-01-01

A full-scale oxidation ditch process for treating sewage was simulated with the ASM2d model and optimized for minimal cost with acceptable performance in terms of ammonium and phosphorus removal. A unified index was introduced by integrating operational costs (aeration energy and sludge production) with effluent violations for performance evaluation. Scenario analysis showed that, in comparison with the baseline (all of the 9 aerators activated), the strategy of activating 5 aerators could save aeration energy significantly with an ammonium violation below 10%. Sludge discharge scenario analysis showed that a sludge discharge flow of 250-300 m3/day (solid retention time (SRT), 13-15 days) was appropriate for the enhancement of phosphorus removal without excessive sludge production. The proposed optimal control strategy was: activating 5 rotating disks operated with a mode of "111100100" ("1" represents activation and "0" represents inactivation) for aeration and sludge discharge flow of 200 m3/day (SRT, 19 days). Compared with the baseline, this strategy could achieve ammonium violation below 10% and TP violation below 30% with substantial reduction of aeration energy cost (46%) and minimal increment of sludge production (< 2%). This study provides a useful approach for the optimization of process operation and control.

Changing attitudes to infection management in primary care: a controlled trial of active versus passive guideline implementation strategies.

PubMed

Onion, C W; Bartzokas, C A

1998-04-01

When attempting to implement evidence-based medicine, such as through clinical guidelines, we often rely on passive educational tactics, for example didactic lectures and bulletins. These methods involve the recipient in relatively superficial processing of information, and any consequent attitude changes can be expected to be short-lived. However, active methods, such as practice-based discussion, should involve recipients in deep processing, with more enduring attitude changes. In this experiment, the aim was to assess the efficacy of an active strategy at promoting deep processing and its effectiveness, relative to a typical passive method, at changing attitudes between groups of GPs over 12 months across an English Health District. All 191 GPs operating from 69 practices in the Wirral Health District of Northwest England were assigned, with minimization of known confounding variables, to three experimental groups: active, passive and control. The groups were shown to have similar learning styles. The objective of the study was to impart knowledge of best management of infections as captured in a series of locally developed clinical guidelines. The passive group GPs were given a copy of the guidelines and were invited to an hour-long lecture event. The GPs in the deep group were given a copy of the guidelines and were invited to engage in an hour-long discussion about the guideline content at their own premises. The control group received neither the guidelines nor any educational contact regarding them. Three months before and 12 months after the interventions, all GPs were sent a postal questionnaire on their preferred empirical antibiotic for 10 common bacterial infections. The responses were compared in order to ascertain whether increased knowledge of best clinical practice was evident in each group. Seventy-five per cent (144/191) of GPs responded to the pre-intervention questionnaire, 62 % (119/191) post-intervention. Thirty-four per cent (22/64) of GPs in the passive group attended the lecture; 91% (60/66) of the active group engaged in discussion at meetings with the authors. A significantly higher proportion of the active group participants' speaking time, during a sample of four visits, was devoted to verbal indicators of active processing than the passive group lecture attenders (difference = 55%, Fisher's exact test P = 0.002, OR = 11.5, 95% CI 2.1-113.4). Inter-observer agreement on the classification of the verbal evidence was highly statistically significant for all classes (Pearson's product moment correlation, P < 0.0005, r = +0.893 to +0.999) except repetition (P > 0.05, r = +0.407). Median compliance of responses with the guidelines improved by 2.5% within the control group and 4% within the passive, but by 23% within the active. The difference between the changes in the active and control groups was highly statistically significant at 17.5% (Mann-Whitney test, P = 0.004, 95% CI 6-29%). However, for the 10 infections, the median difference between the changes in the passive and control groups was not significant at 3% (P = 0.75, 95% CI -8 to +12. The median difference between changes in the active and passive groups was significant at 17% (P = 0.015, 95% CI 7-24%) in favour of the active. An active educational strategy attracted more participation and was more effective at generating deep cognitive processing than a passive strategy. A large improvement, lasting for at least 12 months, in attitude-compliance with guidelines on the optimal treatment of infections was imparted by the active processing method. A typical passive method was much less popular and had an insignificant impact on attitudes. The findings suggest that initiatives aiming to implement evidence-based guidelines must employ active educational strategies if enduring changes in attitude are to result.

Factor structure of the happiness-increasing strategies scales (H-ISS): activities and coping strategies in relation to positive and negative affect.

PubMed

Al Nima, Ali; Garcia, Danilo

2015-01-01

Background. Previous research (Tkach & Lyubomirsky, 2006) shows that there are eight general happiness-increasing strategies: social affiliation, partying, mental control, goal pursuit, passive leisure, active leisure, religion, and direct attempts. The present study investigates the factor structure of the happiness-increasing strategies scales (H-ISS) and their relationship to positive and negative affect. Method. The present study used participants' (N = 1,050 and age mean = 34.21 sd = 12.73) responses to the H-ISS in structural equation modeling analyses. Affect was measured using the Positive Affect Negative Affect Schedule. Results. After small modifications we obtained a good model that contains the original eight factors/scales. Moreover, we found that women tend to use social affiliation, mental control, passive leisure, religion, and direct attempts more than men, while men preferred to engage in partying and clubbing more than women. The H-ISS explained significantly the variance of positive affect (R (2) = .41) and the variance of negative affect (R (2) = .27). Conclusions. Our study is an addition to previous research showing that the factor structure of the happiness-increasing strategies is valid and reliable. However, due to the model fitting issues that arise in the present study, we give some suggestions for improving the instrument.

Agrochemical control of plant water use using engineered abscisic acid receptors.

PubMed

Park, Sang-Youl; Peterson, Francis C; Mosquna, Assaf; Yao, Jin; Volkman, Brian F; Cutler, Sean R

2015-04-23

Rising temperatures and lessening fresh water supplies are threatening agricultural productivity and have motivated efforts to improve plant water use and drought tolerance. During water deficit, plants produce elevated levels of abscisic acid (ABA), which improves water consumption and stress tolerance by controlling guard cell aperture and other protective responses. One attractive strategy for controlling water use is to develop compounds that activate ABA receptors, but agonists approved for use have yet to be developed. In principle, an engineered ABA receptor that can be activated by an existing agrochemical could achieve this goal. Here we describe a variant of the ABA receptor PYRABACTIN RESISTANCE 1 (PYR1) that possesses nanomolar sensitivity to the agrochemical mandipropamid and demonstrate its efficacy for controlling ABA responses and drought tolerance in transgenic plants. Furthermore, crystallographic studies provide a mechanistic basis for its activity and demonstrate the relative ease with which the PYR1 ligand-binding pocket can be altered to accommodate new ligands. Thus, we have successfully repurposed an agrochemical for a new application using receptor engineering. We anticipate that this strategy will be applied to other plant receptors and represents a new avenue for crop improvement.

The effect of Functional Electric Stimulation in stroke patients' motor control - a case report

NASA Astrophysics Data System (ADS)

Pripas, Denise; Rogers Venditi Beas, Allan; Fioramonte, Caroline; Gonsales de Castro, Pedro Claudio; Goroso, Daniel Gustavo; Cecília dos Santos Moreira, Maria

2011-12-01

Functional Electric Stimulation (FES) has been studied as a therapeutic resource to reduce spasticity in hemiplegic patients, however there are no studies about the effects of FES in motor control of these patients during functional tasks like balance maintenance. Muscular activation of gastrocnemius medialis and semitendinosus was investigated in both limbs of a hemiparetic patient during self-disturbed quiet stance before and after FES on tibialis anterior, by surface electromyography. The instant of maximum activation peak of GM and ST were calculated immediately after a motor self-disturbance, in order to observe muscular synergy between these two muscles, and possible balance strategies used (ankle or hip strategy). At the preserved limb there occurred distal-proximal synergy (GM followed by ST), expected for small perturbations; however, at spastic limb there was inversion of this synergy (proximal-distal) after FES. It is possible that intervention of electricity had inhibited synergical pathways due to antidromic effect, making it difficult to use ankle strategy in the spastic limb.

Flow Navigation by Smart Microswimmers via Reinforcement Learning

NASA Astrophysics Data System (ADS)

Colabrese, Simona; Gustavsson, Kristian; Celani, Antonio; Biferale, Luca

2017-04-01

Smart active particles can acquire some limited knowledge of the fluid environment from simple mechanical cues and exert a control on their preferred steering direction. Their goal is to learn the best way to navigate by exploiting the underlying flow whenever possible. As an example, we focus our attention on smart gravitactic swimmers. These are active particles whose task is to reach the highest altitude within some time horizon, given the constraints enforced by fluid mechanics. By means of numerical experiments, we show that swimmers indeed learn nearly optimal strategies just by experience. A reinforcement learning algorithm allows particles to learn effective strategies even in difficult situations when, in the absence of control, they would end up being trapped by flow structures. These strategies are highly nontrivial and cannot be easily guessed in advance. This Letter illustrates the potential of reinforcement learning algorithms to model adaptive behavior in complex flows and paves the way towards the engineering of smart microswimmers that solve difficult navigation problems.

Task-level strategies for human sagittal-plane running maneuvers are consistent with robotic control policies.

PubMed

Qiao, Mu; Jindrich, Devin L

2012-01-01

The strategies that humans use to control unsteady locomotion are not well understood. A "spring-mass" template comprised of a point mass bouncing on a sprung leg can approximate both center of mass movements and ground reaction forces during running in humans and other animals. Legged robots that operate as bouncing, "spring-mass" systems can maintain stable motion using relatively simple, distributed feedback rules. We tested whether the changes to sagittal-plane movements during five running tasks involving active changes to running height, speed, and orientation were consistent with the rules used by bouncing robots to maintain stability. Changes to running height were associated with changes to leg force but not stance duration. To change speed, humans primarily used a "pogo stick" strategy, where speed changes were associated with adjustments to fore-aft foot placement, and not a "unicycle" strategy involving systematic changes to stance leg hip moment. However, hip moments were related to changes to body orientation and angular speed. Hip moments could be described with first order proportional-derivative relationship to trunk pitch. Overall, the task-level strategies used for body control in humans were consistent with the strategies employed by bouncing robots. Identification of these behavioral strategies could lead to a better understanding of the sensorimotor mechanisms that allow for effective unsteady locomotion.

Feasibility of controlling CD38-CAR T cell activity with a Tet-on inducible CAR design

PubMed Central

Poels, Renée; Mulders, Manon J.; van de Donk, Niels W. C. J.; Themeli, Maria; Lokhorst, Henk M.; Mutis, Tuna

2018-01-01

Recent clinical advances with chimeric antigen receptor (CAR) T cells have led to the accelerated clinical approval of CD19-CARs to treat acute lymphoblastic leukemia. The CAR T cell therapy is nevertheless associated with toxicities, especially if the CARs are not entirely tumor-specific. Therefore, strategies for controlling the CAR T cell activity are required to improve their safety profile. Here, by using the multiple myeloma (MM)-associated CD38 molecule as target molecule, we tested the feasibility and utility of a doxycycline (DOX) inducible Tet-on CD38-CAR design to control the off-target toxicities of CAR T cells. Using CARs with high affinity to CD38, we demonstrate that this strategy allows the proper induction of CD38-CARs and CAR-mediated T cell cytotoxicity in a DOX-dose dependent manner. Especially when the DOX dose was limited to 10ng/ml, its removal resulted in a relatively rapid decay of CAR- related off-tumor effects within 24 hours, indicating the active controllability of undesired CAR activity. This Tet-on CAR design also allowed us to induce the maximal anti-MM cytotoxic activity of affinity-optimized CD38-CAR T cells, which already display a low toxicity profile, hereby adding a second level of safety to these cells. Collectively, these results indicate the possibility to utilize this DOX inducible CAR-design to actively regulate the CAR-mediated activities of therapeutic T cells. We therefore conclude that the Tet-on system may be more advantageous above suicide-genes to control the potential toxicities of CAR T cells without the need to destroy them permanently. PMID:29847570

A comparison between IMSC, PI and MIMSC methods in controlling the vibration of flexible systems

NASA Technical Reports Server (NTRS)

Baz, A.; Poh, S.

1987-01-01

A comparative study is presented between three active control algorithms which have proven to be successful in controlling the vibrations of large flexible systems. These algorithms are: the Independent Modal Space Control (IMSC), the Pseudo-inverse (PI), and the Modified Independent Modal Space Control (MIMSC). Emphasis is placed on demonstrating the effectiveness of the MIMSC method in controlling the vibration of large systems with small number of actuators by using an efficient time sharing strategy. Such a strategy favors the MIMSC over the IMSC method, which requires a large number of actuators to control equal number of modes, and also over the PI method which attempts to control large number of modes with smaller number of actuators through the use of an in-exact statistical realization of a modal controller. Numerical examples are presented to illustrate the main features of the three algorithms and the merits of the MIMSC method.

Investigating the Relationship between Instructors’ Use of Active-Learning Strategies and Students’ Conceptual Understanding and Affective Changes in Introductory Biology: A Comparison of Two Active-Learning Environments

PubMed Central

Cleveland, Lacy M.; Olimpo, Jeffrey T.; DeChenne-Peters, Sue Ellen

2017-01-01

In response to calls for reform in undergraduate biology education, we conducted research examining how varying active-learning strategies impacted students’ conceptual understanding, attitudes, and motivation in two sections of a large-lecture introductory cell and molecular biology course. Using a quasi-experimental design, we collected quantitative data to compare participants’ conceptual understanding, attitudes, and motivation in the biological sciences across two contexts that employed different active-learning strategies and that were facilitated by unique instructors. Students participated in either graphic organizer/worksheet activities or clicker-based case studies. After controlling for demographic and presemester affective differences, we found that students in both active-learning environments displayed similar and significant learning gains. In terms of attitudinal and motivational data, significant differences were observed for two attitudinal measures. Specifically, those students who had participated in graphic organizer/worksheet activities demonstrated more expert-like attitudes related to their enjoyment of biology and ability to make real-world connections. However, all motivational and most attitudinal data were not significantly different between the students in the two learning environments. These data reinforce the notion that active learning is associated with conceptual change and suggests that more research is needed to examine the differential effects of varying active-learning strategies on students’ attitudes and motivation in the domain. PMID:28389428

Active control of transmission loss with smart foams.

PubMed

Kundu, Abhishek; Berry, Alain

2011-02-01

Smart foams combine the complimentary advantages of passive foam material and spatially distributed piezoelectric actuator embedded in it for active noise control applications. In this paper, the problem of improving the transmission loss of smart foams using active control strategies has been investigated both numerically and experimentally inside a waveguide under the condition of plane wave propagation. The finite element simulation of a coupled noise control system has been undertaken with three different smart foam designs and their effectiveness in cancelling the transmitted wave downstream of the smart foam have been studied. The simulation results provide insight into the physical phenomenon of active noise cancellation and explain the impact of the smart foam designs on the optimal active control results. Experimental studies aimed at implementing the real-time control for transmission loss optimization have been performed using the classical single input/single output filtered-reference least mean squares algorithm. The active control results with broadband and single frequency primary source inputs demonstrate a good improvement in the transmission loss of the smart foams. The study gives a comparative description of the transmission and absorption control problems in light of the modification of the vibration response of the piezoelectric actuator under active control.

Adopting an Evidence-Based Lifestyle Physical Activity Program: Dissemination Study Design and Methods.

PubMed

Dunn, Andrea L; Buller, David B; Dearing, James W; Cutter, Gary; Guerra, Michele; Wilcox, Sara; Bettinghaus, Erwin P

2012-06-01

BACKGROUND: There is a scarcity of research studies that have examined academic-commercial partnerships to disseminate evidence-based physical activity programs. Understanding this approach to dissemination is essential because academic-commercial partnerships are increasingly common. Private companies have used dissemination channels and strategies to a degree that academicians have not, and declining resources require academicians to explore these partnerships. PURPOSE: This paper describes a retrospective case-control study design including the methods, demographics, organizational decision-making, implementation rates, and marketing strategy for Active Living Every Day (ALED), an evidence-based lifestyle physical activity program that has been commercially available since 2001. Evidence-based public health promotion programs rely on organizations and targeted sectors to disseminate these programs although relatively little is known about organizational-level and sector-level influences that lead to their adoption and implementation. METHODS: Cases (n=154) were eligible if they had signed an ALED license agreement with Human Kinetics (HK), publisher of the program's textbooks and facilitator manuals, between 2001 and 2008. Two types of controls were matched (2:2:1) and stratified by sector and region. Active controls (Control 1; n=319) were organizations that contacted HK to consider adopting ALED. Passive controls (Control 2; n=328) were organizations that received unsolicited marketing materials and did not initiate contact with HK. We used Diffusion of Innovations Theory (DIT) constructs as the basis for developing the survey of cases and controls. RESULTS: Using the multi-method strategy recommended by Dillman, a total of n=801 cases and controls were surveyed. Most organizations were from the fitness sector followed by medical, nongovernmental, governmental, educational, worksite and other sectors with significantly higher response rates from government, educational and medical sectors compared with fitness and other sectors, (p=0.02). More cases reported being involved in the decision to adopt ALED (p<0.0001). Data indicate that a low percentage of controls had ever heard of ALED despite repeated marketing and offering other types of physical activity programs and services. Finally, slightly over half of the adopters reported they had actually implemented the ALED program. CONCLUSION: Dissemination research requires new perspectives and designs to produce valid insights about the results of dissemination efforts. This study design, survey methods and theoretically-based questions can serve as a useful model for other evidence-based public health interventions that are marketed by commercial publishers to better understand key issues related to adoption and implementation of evidence-based programs.

Intrinsic biocontainment: Multiplex genome safeguards combine transcriptional and recombinational control of essential yeast genes

PubMed Central

Cai, Yizhi; Agmon, Neta; Choi, Woo Jin; Ubide, Alba; Stracquadanio, Giovanni; Caravelli, Katrina; Hao, Haiping; Bader, Joel S.; Boeke, Jef D.

2015-01-01

Biocontainment may be required in a wide variety of situations such as work with pathogens, field release applications of engineered organisms, and protection of intellectual properties. Here, we describe the control of growth of the brewer’s yeast, Saccharomyces cerevisiae, using both transcriptional and recombinational “safeguard” control of essential gene function. Practical biocontainment strategies dependent on the presence of small molecules require them to be active at very low concentrations, rendering them inexpensive and difficult to detect. Histone genes were controlled by an inducible promoter and controlled by 30 nM estradiol. The stability of the engineered genes was separately regulated by the expression of a site-specific recombinase. The combined frequency of generating viable derivatives when both systems were active was below detection (<10−10), consistent with their orthogonal nature and the individual escape frequencies of <10−6. Evaluation of escaper mutants suggests strategies for reducing their emergence. Transcript profiling and growth test suggest high fitness of safeguarded strains, an important characteristic for wide acceptance. PMID:25624482

Active control of ECCD-induced tearing mode stabilization in coupled NIMROD/GENRAY HPC simulations

NASA Astrophysics Data System (ADS)

Jenkins, Thomas; Kruger, Scott; Held, Eric

2013-10-01

Actively controlled ECCD applied in or near magnetic islands formed by NTMs has been successfully shown to control/suppress these modes, despite uncertainties in island O-point locations (where induced current is most stabilizing) relative to the RF deposition region. Integrated numerical models of the mode stabilization process can resolve these uncertainties and augment experimental efforts to determine optimal ITER NTM stabilization strategies. The advanced SWIM model incorporates RF effects in the equations/closures of extended MHD as 3D (not toroidal or bounce-averaged) quasilinear diffusion coefficients. Equilibration of driven current within the island geometry is modeled using the same extended MHD dynamics governing the physics of island formation, yielding a more accurate/self-consistent picture of island response to RF drive. Additionally, a numerical active feedback control system gathers data from synthetic diagnostics to dynamically trigger & spatially align the RF fields. Computations which model the RF deposition using ray tracing, assemble the 3D QL operator from ray & profile data, calculate the resultant xMHD forces, and dynamically realign the RF to more efficiently stabilize modes are presented; the efficacy of various control strategies is also discussed. Supported by the SciDAC Center for Extended MHD Modeling (CEMM); see also https://cswim.org.

Characterizing Types of Human Mobility to Inform Differential and Targeted Malaria Elimination Strategies in Northeast Cambodia

PubMed Central

Peeters Grietens, Koen; Gryseels, Charlotte; Dierickx, Susan; Bannister-Tyrrell, Melanie; Trienekens, Suzan; Uk, Sambunny; Phoeuk, Pisen; Suon, Sokha; Set, Srun; Gerrets, René; Hoibak, Sarah; Muela Ribera, Joan; Hausmann-Muela, Susanna; Tho, Sochantha; Durnez, Lies; Sluydts, Vincent; d’Alessandro, Umberto; Coosemans, Marc; Erhart, Annette

2015-01-01

Human population movements currently challenge malaria elimination in low transmission foci in the Greater Mekong Subregion. Using a mixed-methods design, combining ethnography (n = 410 interviews), malariometric data (n = 4996) and population surveys (n = 824 indigenous populations; n = 704 Khmer migrants) malaria vulnerability among different types of mobile populations was researched in the remote province of Ratanakiri, Cambodia. Different structural types of human mobility were identified, showing differential risk and vulnerability. Among local indigenous populations, access to malaria testing and treatment through the VMW-system and LLIN coverage was high but control strategies failed to account for forest farmers’ prolonged stays at forest farms/fields (61% during rainy season), increasing their exposure (p = 0.002). The Khmer migrants, with low acquired immunity, active on plantations and mines, represented a fundamentally different group not reached by LLIN-distribution campaigns since they were largely unregistered (79%) and unaware of the local VMW-system (95%) due to poor social integration. Khmer migrants therefore require control strategies including active detection, registration and immediate access to malaria prevention and control tools from which they are currently excluded. In conclusion, different types of mobility require different malaria elimination strategies. Targeting mobility without an in-depth understanding of malaria risk in each group challenges further progress towards elimination. PMID:26593245

Employee engagement factors that affect enrollment compared with retention in two coaching programs--the ACTIVATE study.

PubMed

Terry, Paul E; Fowles, Jinnet B; Harvey, Lisa

2010-06-01

This article describes enrollment and retention results from a randomized controlled trial that tested differences between a traditional worksite health promotion program and an activated consumer program on health behaviors and health status. A control arm was included. Baseline survey and clinical data were collected from 631 of 1628 eligible employees (39% response rate) between March and June of 2005. Retention data were collected in March 2007-12 months into an 18-month program. At baseline, participants in the 6 groups (3 arms in each of 2 companies) were comparable in health status but not in patient activation status. Enrollment of high-risk employees into the 2 individualized coaching programs (one focused on traditional health promotion, the other focused on activated consumer navigation) varied significantly by industry type, smoking status, and patient activation. In contrast, retention in the coaching programs was related to sex, age, and industry type. Our findings suggest that one set of strategies may be needed to encourage program enrollment while a distinctly different set of strategies may be needed to sustain participation.

Effectiveness of false correction strategy on science reading comprehension

NASA Astrophysics Data System (ADS)

Ghent, Cynthia Anne

False-correction reading strategy theoretically prompted college students to activate their prior knowledge when provided false statements linked to a portion of their biology textbook. This strategy is based in elaborative interrogation theory, which suggests that prompting readers to answer interrogatives about text students are reading increases their comprehension of that text. These interrogatives always asked "why" statements pulled from a text, one sentence in length, were "true." True statements in this study based on a text were converted by the experimenter into false statements, one sentence in length. Students were requested to rewrite each statement (n=12) on average every 200 words in a text as they were reading, converting each false statement into a true statement. These students outperformed other students requested to reread the same biology text twice (an established placebo-control strategy). These students, in turn, outperformed still other students reading an unrelated control text taken from the same textbook used only to establish a prior knowledge baseline for all students included in this study. Students participating in this study were enrolled students in an undergraduate introductory general biology course designed for non-majors. A three-group, posttest-only, randomized experimental control-group design was used to prevent pretest activation of students' prior knowledge thus increasing chances of producing evidence of false-correction effectiveness and to begin augmenting potential generalizability to science classrooms. Students' (n=357) general biology knowledge, verbal ability, and attempts to use the false correction strategy were collected and analyzed. Eight of the participants were interviewed by the researcher in a first attempt in this domain to collect data on participants' points of view about the strategy. The results of this study are not yet recommended for use in authentic school settings as further research is indicated.

Investigation of crew performance in a multi-vehicle supervisory control task

NASA Technical Reports Server (NTRS)

Miller, R. A.; Plamondon, B. D.; Jagacinski, R. J.; Kirlik, A. C.

1986-01-01

Crew information processing and decision making in a supervisory control task which is loosely based on the mission of future generation helicopters is measured and represented. Subjects control the motion and activities of their own vehicle and direct the activities of four additional craft. The task involves searching an uncertain environment for cargo and enemies, returning cargo to home base and destroying enemies while attempting to avoid destruction of the scout and the supervised vehicles. A series of experiments with two-person crews and one-person crews were performed. Resulting crew performance was modeled with the objective of describing and understanding the information processing strategies utilized. Of particular interest are problem simplification strategies under time stress and high work load, simplification and compensation in the one-person cases, crew coordination in the two-person cases, and the relationship between strategy and errors in all cases. The results should provide some insight into the effective use of aids, particularly aids based on artificial intelligence, for similar tasks. The simulation is described which is used for the study and some preliminary results from the first two-person crew study are discussed.

A review of measles supplementary immunization activities and the implications for Pacific Island countries and territories.

PubMed

Clements, C John; Soakai, Taniela Sunia; Sadr-Azodi, Nahad

2017-02-01

Standard measles control strategies include achieving high levels of measles vaccine coverage using routine delivery systems, supplemented by mass immunization campaigns as needed to close population immunity gaps. Areas covered: This review looks at how supplementary immunization activities (SIAs) have contributed to measles control globally, and asks whether such a strategy has a place in Pacific Islands today. Expert commentary: Very high coverage with two doses of measles vaccine seems to be the optimal strategy for controlling measles. By 2015, all but two Pacific Islands had introduced a second dose in the routine schedule; however, a number of countries have not yet reached high coverage with their second dose. The literature and the country reviews reported here suggest that a high coverage SIA combined with one dose of measles vaccine given in the routine system will also do the job. The arguments for and against the use of SIAs are complex, but it is clear that to be effective, SIAs need to be well designed to meet specific needs, must be carried out effectively and safely with very high coverage, and should, when possible, carry with them other public health interventions to make them even more cost-effective.

Which therapeutic strategy will achieve a cure for HIV-1?

PubMed

Cillo, Anthony R; Mellors, John W

2016-06-01

Strategies to achieve a cure for HIV-1 infection can be broadly classified into three categories: eradication cure (elimination of all viral reservoirs), functional cure (immune control without reservoir eradication), or a hybrid cure (reservoir reduction with improved immune control). The many HIV-1 cure strategies being investigated include modification of host cells to resist HIV-1, engineered T cells to eliminate HIV-infected cells, broadly HIV-1 neutralizing monoclonal antibodies, and therapeutic vaccination, but the 'kick and kill' strategy to expose latent HIV-1 with latency reversing agents (LRAs) and kill the exposed cells through immune effector functions is currently the most actively pursued. It is unknown, however, whether LRAs can deplete viral reservoirs in vivo or whether current LRAs are sufficiently safe for clinical use. Copyright © 2016. Published by Elsevier B.V.

Redox-Controlled Olefin (Co)Polymerization Catalyzed by Ferrocene-Bridged Phosphine-Sulfonate Palladium Complexes.

PubMed

Chen, Min; Yang, Bangpei; Chen, Changle

2015-12-14

The facile and reversible interconversion between neutral and oxidized forms of palladium complexes containing ferrocene-bridged phosphine sulfonate ligands was demonstrated. The activity of these palladium complexes could be controlled using redox reagents during ethylene homopolymerization, ethylene/methyl acrylate copolymerization, and norbornene oligomerization. Specifically in norbornene oligomerization, the neutral complexes were not active at all whereas the oxidized counterparts showed appreciable activity. In situ switching between the neutral and oxidized forms resulted in an interesting "off" and "on" behavior in norbornene oligomerization. This work provides a new strategy to control the olefin polymerization process. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Banding the world together; the global growth of control banding and qualitative occupational risk management.

PubMed

Zalk, David M; Heussen, Ga Henri

2011-12-01

Control Banding (CB) strategies to prevent work-related illness and injury for 2.5 billion workers without access to health and safety professionals has grown exponentially this last decade. CB originates from the pharmaceutical industry to control active pharmaceutical ingredients without a complete toxicological basis and therefore no occupational exposure limits. CB applications have broadened into chemicals in general - including new emerging risks like nanomaterials and recently into ergonomics and injury prevention. CB is an action-oriented qualitative risk assessment strategy offering solutions and control measures to users through "toolkits". Chemical CB toolkits are user-friendly approaches used to achieve workplace controls in the absence of firm toxicological and quantitative exposure information. The model (technical) validation of these toolkits is well described, however firm operational analyses (implementation aspects) are lacking. Consequentially, it is often not known if toolkit use leads to successful interventions at individual workplaces. This might lead to virtual safe workplaces without knowing if workers are truly protected. Upcoming international strategies from the World Health Organization Collaborating Centers request assistance in developing and evaluating action-oriented procedures for workplace risk assessment and control. It is expected that to fulfill this strategy's goals, CB approaches will continue its important growth in protecting workers.

Flight tests for the assessment of task performance and control activity

NASA Technical Reports Server (NTRS)

Pausder, H. J.; Hummes, D.

1982-01-01

The tests were performed with the helicopters BO 105 and UH-1D. Closely connected with tactical demands the six test pilots' task was to minimize the time and the altitude over the obstacles. The data reduction yields statistical evaluation parameters describing the control activity of the pilots and the achieved task performance. The results are shown in form of evaluation diagrams. Additionally dolphin tests with varied control strategy were performed to get more insight into the influence of control techniques. From these test results recommendations can be derived to emphasize the direct force control and to reduce the collective to pitch crosscoupling for the dolphin.

Interventions to Promote Physical Activity in Older People with Type 2 Diabetes Mellitus: A Systematic Review

PubMed Central

Sazlina, Shariff-Ghazali; Browning, Colette; Yasin, Shajahan

2013-01-01

Introduction: Type 2 diabetes mellitus (T2DM) among people aged 60 years and above is a growing public health problem. Regular physical activity is one of the key elements in the management of T2DM. Recommendations suggest that older people with T2DM will benefit from regular physical activity for better disease control and delaying complications. Despite the known benefits, many remain sedentary. Hence, this review assessed interventions for promoting physical activity in persons aged 65 years and older with T2DM. Methods: A literature search was conducted using Ovid MEDLINE, PubMed, EMBASE, SPORTDiscus, and CINAHL databases to retrieve articles published between January 2000 and December 2012. Randomized controlled trials and quasi-experimental designs comparing different strategies to increase physical activity level in persons aged 65 years and older with T2DM were included. The methodological quality of studies was assessed. Results: Twenty-one eligible studies were reviewed, only six studies were rated as good quality and only one study specifically targeted persons aged 65 years and older. Personalized coaching, goal setting, peer support groups, use of technology, and physical activity monitors were proven to increase the level of physical activity. Incorporation of health behavior theories and follow-up supports also were successful strategies. However, the methodological quality and type of interventions promoting physical activity of the included studies in this review varied widely across the eligible studies. Conclusion: Strategies that increased level of physical activity in persons with T2DM are evident but most studies focused on middle-aged persons and there was a lack of well-designed trials. Hence, more studies of satisfactory methodological quality with interventions promoting physical activity in older people are required. PMID:24392445

A real-time comparison between direct control, sequential pattern recognition control and simultaneous pattern recognition control using a Fitts’ law style assessment procedure

PubMed Central

2014-01-01

Background Pattern recognition (PR) based strategies for the control of myoelectric upper limb prostheses are generally evaluated through offline classification accuracy, which is an admittedly useful metric, but insufficient to discuss functional performance in real time. Existing functional tests are extensive to set up and most fail to provide a challenging, objective framework to assess the strategy performance in real time. Methods Nine able-bodied and two amputee subjects gave informed consent and participated in the local Institutional Review Board approved study. We designed a two-dimensional target acquisition task, based on the principles of Fitts’ law for human motor control. Subjects were prompted to steer a cursor from the screen center of into a series of subsequently appearing targets of different difficulties. Three cursor control systems were tested, corresponding to three electromyography-based prosthetic control strategies: 1) amplitude-based direct control (the clinical standard of care), 2) sequential PR control, and 3) simultaneous PR control, allowing for a concurrent activation of two degrees of freedom (DOF). We computed throughput (bits/second), path efficiency (%), reaction time (second), and overshoot (%)) and used general linear models to assess significant differences between the strategies for each metric. Results We validated the proposed methodology by achieving very high coefficients of determination for Fitts’ law. Both PR strategies significantly outperformed direct control in two-DOF targets and were more intuitive to operate. In one-DOF targets, the simultaneous approach was the least precise. The direct control was efficient in one-DOF targets but cumbersome to operate in two-DOF targets through a switch-depended sequential cursor control. Conclusions We designed a test, capable of comprehensively describing prosthetic control strategies in real time. When implemented on control subjects, the test was able to capture statistically significant differences (p < 0.05) in control strategies when considering throughputs, path efficiencies and reaction times. Of particular note, we found statistically significant (p < 0.01) improvements in throughputs and path efficiencies with simultaneous PR when compared to direct control or sequential PR. Amputees could readily achieve the task; however a limited number of subjects was tested and a statistical analysis was not performed with that population. PMID:24886664

A real-time comparison between direct control, sequential pattern recognition control and simultaneous pattern recognition control using a Fitts' law style assessment procedure.

PubMed

Wurth, Sophie M; Hargrove, Levi J

2014-05-30

Pattern recognition (PR) based strategies for the control of myoelectric upper limb prostheses are generally evaluated through offline classification accuracy, which is an admittedly useful metric, but insufficient to discuss functional performance in real time. Existing functional tests are extensive to set up and most fail to provide a challenging, objective framework to assess the strategy performance in real time. Nine able-bodied and two amputee subjects gave informed consent and participated in the local Institutional Review Board approved study. We designed a two-dimensional target acquisition task, based on the principles of Fitts' law for human motor control. Subjects were prompted to steer a cursor from the screen center of into a series of subsequently appearing targets of different difficulties. Three cursor control systems were tested, corresponding to three electromyography-based prosthetic control strategies: 1) amplitude-based direct control (the clinical standard of care), 2) sequential PR control, and 3) simultaneous PR control, allowing for a concurrent activation of two degrees of freedom (DOF). We computed throughput (bits/second), path efficiency (%), reaction time (second), and overshoot (%)) and used general linear models to assess significant differences between the strategies for each metric. We validated the proposed methodology by achieving very high coefficients of determination for Fitts' law. Both PR strategies significantly outperformed direct control in two-DOF targets and were more intuitive to operate. In one-DOF targets, the simultaneous approach was the least precise. The direct control was efficient in one-DOF targets but cumbersome to operate in two-DOF targets through a switch-depended sequential cursor control. We designed a test, capable of comprehensively describing prosthetic control strategies in real time. When implemented on control subjects, the test was able to capture statistically significant differences (p < 0.05) in control strategies when considering throughputs, path efficiencies and reaction times. Of particular note, we found statistically significant (p < 0.01) improvements in throughputs and path efficiencies with simultaneous PR when compared to direct control or sequential PR. Amputees could readily achieve the task; however a limited number of subjects was tested and a statistical analysis was not performed with that population.

Control programme for cystic echinococcosis in Uruguay.

PubMed

Irabedra, Pilar; Ferreira, Ciro; Sayes, Julio; Elola, Susana; Rodríguez, Miriam; Morel, Noelia; Segura, Sebastian; Santos, Estela Dos; Guisantes, Jorge A

2016-05-24

Cystic echinococcosis is a highly endemic parasitic zoonosis that is present in the Southern Cone countries of America. For several decades, various prevention and control programmes have been implemented in different countries and regions, with varying results. In Uruguay, a new control programme was implemented in 2006 that employed new strategies for canine diagnosis and treatment, dog population control, diagnosis in humans, epidemiological surveillance, and health education, including community participation. The control programme in Uruguay addresses the control and surveillance of the disease from a holistic perspective based on Primary Health Care, which has strengthened the community's participation in developing and coordinating activities in an interdisciplinary manner. Similarly, the control programme that is currently implemented is based on a risk-focused approach. The surveillance and control measures were focused on small villages and extremely poor urban areas. In this study, the strategies used and the results obtained from 2008-2013 are analysed and discussed.

Active case finding of tuberculosis: historical perspective and future prospects

PubMed Central

Golub, J. E.; Mohan, C. I.; Comstock, G. W.; Chaisson, R. E.

2015-01-01

SUMMARY Despite a history of remarkable scientific achievements in microbiology and therapeutics, tuberculosis (TB) continues to pose an extraordinary threat to human health. Case finding and treatment of TB disease are the principal means of controlling transmission and reducing incidence. This review presents a historical perspective of active case finding (ACF) of TB, detailing case detection strategies that have been used over the last century. This review is divided into the following sections: mass radiography, house-to-house surveys, out-patient case detection, enhanced case finding, high-risk populations and cost-effectiveness. The report concludes with a discussion and recommendations for future case finding strategies. Understanding the strengths and weaknesses of these methods will help inform and shape ACF as a TB control policy in the twenty-first century. PMID:16333924

Make a Difference at Your School! CDC Resources Can Help You Implement Strategies to Prevent Obesity Among Children and Adolescents

ERIC Educational Resources Information Center

Centers for Disease Control and Prevention, 2008

2008-01-01

The Centers for Disease Control and Prevention (CDC) reviews scientific evidence to determine which school-based policies and practices are most likely to improve key health behaviors among young people, including physical activity and healthy eating. In this document, the CDC identifies ten strategies to help schools prevent obesity by promoting…

Synthesis of Nanoporous Activated Iridium Oxide Films by Anodized Aluminum Oxide Templated Atomic Layer Deposition

DTIC Science & Technology

2010-11-01

number of deposition strategies, including sputtering [10–12] and electrodeposition [13,14]. With all synthesis strategies, control of the film...to 10% ozone in 400 sccm O2 for 10 min. A 20 Å Al2O3 film was then deposited as a nucleation layer by iterative exposures of trimethyla- luminum and

Cognitive Strategies and Physical Activity in Older Adults: A Discriminant Analysis

PubMed Central

Ferrand, Claude; Audiffren, Michel

2018-01-01

Background Although a number of studies have examined sociodemographic, psychosocial, and environmental determinants of the level of physical activity (PA) for older people, little attention has been paid to the predictive power of cognitive strategies for independently living older adults. However, cognitive strategies have recently been considered to be critical in the management of day-to-day living. Methods Data were collected from 243 men and women aged 55 years and older living in France using face-to-face interviews between 2011 and 2013. Results A stepwise discriminant analysis selected five predictor variables (age, perceived health status, barriers' self-efficacy, internal memory, and attentional control strategies) of the level of PA. The function showed that the rate of correct prediction was 73% for the level of PA. The calculated discriminant function based on the five predictor variables is useful for detecting individuals at high risk of lapses once engaged in regular PA. Conclusions This study highlighted the need to consider cognitive functions as a determinant of the level of PA and, more specifically, those cognitive functions related to executive functions (internal memory and attentional control), to facilitate the maintenance of regular PA. These results are discussed in relation to successful aging. PMID:29850247

Cognitive Strategies and Physical Activity in Older Adults: A Discriminant Analysis.

PubMed

André, Nathalie; Ferrand, Claude; Albinet, Cédric; Audiffren, Michel

2018-01-01

Although a number of studies have examined sociodemographic, psychosocial, and environmental determinants of the level of physical activity (PA) for older people, little attention has been paid to the predictive power of cognitive strategies for independently living older adults. However, cognitive strategies have recently been considered to be critical in the management of day-to-day living. Data were collected from 243 men and women aged 55 years and older living in France using face-to-face interviews between 2011 and 2013. A stepwise discriminant analysis selected five predictor variables (age, perceived health status, barriers' self-efficacy, internal memory, and attentional control strategies) of the level of PA. The function showed that the rate of correct prediction was 73% for the level of PA. The calculated discriminant function based on the five predictor variables is useful for detecting individuals at high risk of lapses once engaged in regular PA. This study highlighted the need to consider cognitive functions as a determinant of the level of PA and, more specifically, those cognitive functions related to executive functions (internal memory and attentional control), to facilitate the maintenance of regular PA. These results are discussed in relation to successful aging.

Predicting tree mortality following gypsy moth defoliation

Treesearch

D.E. Fosbroke; R.R. Hicks; K.W. Gottschalk

1991-01-01

Appropriate application of gypsy moth control strategies requires an accurate prediction of the distribution and intensity of tree mortality prior to defoliation. This prior information is necessary to better target investments in control activities where they are needed. This poster lays the groundwork for developing hazard-rating systems for forests of the...

What Students Learn from Hands-On Activities

ERIC Educational Resources Information Center

Schwichow, Martin; Zimmerman, Corinne; Croker, Steve; Härtig, Hendrik

2016-01-01

The ability to design and interpret controlled experiments is an important scientific process skill and a common objective of science standards. Numerous intervention studies have investigated how the control-of-variables-strategy (CVS) can be introduced to students. However, a meta-analysis of 72 intervention studies found that the opportunity to…

A new balancing three level three dimensional space vector modulation strategy for three level neutral point clamped four leg inverter based shunt active power filter controlling by nonlinear back stepping controllers.

PubMed

Chebabhi, Ali; Fellah, Mohammed Karim; Kessal, Abdelhalim; Benkhoris, Mohamed F

2016-07-01

In this paper is proposed a new balancing three-level three dimensional space vector modulation (B3L-3DSVM) strategy which uses a redundant voltage vectors to realize precise control and high-performance for a three phase three-level four-leg neutral point clamped (NPC) inverter based Shunt Active Power Filter (SAPF) for eliminate the source currents harmonics, reduce the magnitude of neutral wire current (eliminate the zero-sequence current produced by single-phase nonlinear loads), and to compensate the reactive power in the three-phase four-wire electrical networks. This strategy is proposed in order to gate switching pulses generation, dc bus voltage capacitors balancing (conserve equal voltage of the two dc bus capacitors), and to switching frequency reduced and fixed of inverter switches in same times. A Nonlinear Back Stepping Controllers (NBSC) are used for regulated the dc bus voltage capacitors and the SAPF injected currents to robustness, stabilizing the system and to improve the response and to eliminate the overshoot and undershoot of traditional PI (Proportional-Integral). Conventional three-level three dimensional space vector modulation (C3L-3DSVM) and B3L-3DSVM are calculated and compared in terms of error between the two dc bus voltage capacitors, SAPF output voltages and THDv, THDi of source currents, magnitude of source neutral wire current, and the reactive power compensation under unbalanced single phase nonlinear loads. The success, robustness, and the effectiveness of the proposed control strategies are demonstrated through simulation using Sim Power Systems and S-Function of MATLAB/SIMULINK. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Light-switchable systems for remotely controlled drug delivery.

PubMed

Shim, Gayong; Ko, Seungbeom; Kim, Dongyoon; Le, Quoc-Viet; Park, Gyu Thae; Lee, Jaiwoo; Kwon, Taekhyun; Choi, Han-Gon; Kim, Young Bong; Oh, Yu-Kyoung

2017-12-10

Light-switchable systems have recently received attention as a new mode of remotely controlled drug delivery. In the past, a multitude of nanomedicine studies have sought to enhance the specificity of drug delivery to target sites by focusing on receptors overexpressed on malignant cells or environmental features of diseases sites. Despite these immense efforts, however, there are few clinically available nanomedicines. We need a paradigm shift in drug delivery. One strategy that may overcome the limitations of pathophysiology-based drug delivery is the use of remotely controlled delivery technology. Unlike pathophysiology-based active drug targeting strategies, light-switchable systems are not affected by the heterogeneity of cells, tissue types, and/or microenvironments. Instead, they are triggered by remote light (i.e., near-infrared) stimuli, which are absorbed by photoresponsive molecules or three-dimensional nanostructures. The sequential conversion of light to heat or reactive oxygen species can activate drug release and allow it to be spatio-temporally controlled. Light-switchable systems have been used to activate endosomal drug escape, modulate the release of chemical and biological drugs, and alter nanoparticle structures to control the release rates of drugs. This review will address the limitations of pathophysiology-based drug delivery systems, the current status of light-based remote-switch systems, and future directions in the application of light-switchable systems for remotely controlled drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

pH-Controlled Assembly of DNA Tiles

DOE PAGES

Amodio, Alessia; Adedeji, Abimbola Feyisara; Castronovo, Matteo; ...

2016-09-15

We demonstrate a strategy to trigger and finely control the assembly of supramolecular DNA nanostructures with pH. Control is achieved via a rationally designed strand displacement circuit that responds to pH and activates a downstream DNA tile self-assembly process. We observe that the DNA structures form under neutral/basic conditions, while the self-assembly process is suppressed under acidic conditions. The strategy presented here demonstrates a modular approach toward building systems capable of processing biochemical inputs and finely controlling the assembly of DNA-based nanostructures under isothermal conditions. In particular, the presented architecture is relevant for the development of complex DNA devices ablemore » to sense and respond to molecular markers associated with abnormal metabolism.« less

pH-Controlled Assembly of DNA Tiles

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

Amodio, Alessia; Adedeji, Abimbola Feyisara; Castronovo, Matteo

We demonstrate a strategy to trigger and finely control the assembly of supramolecular DNA nanostructures with pH. Control is achieved via a rationally designed strand displacement circuit that responds to pH and activates a downstream DNA tile self-assembly process. We observe that the DNA structures form under neutral/basic conditions, while the self-assembly process is suppressed under acidic conditions. The strategy presented here demonstrates a modular approach toward building systems capable of processing biochemical inputs and finely controlling the assembly of DNA-based nanostructures under isothermal conditions. In particular, the presented architecture is relevant for the development of complex DNA devices ablemore » to sense and respond to molecular markers associated with abnormal metabolism.« less

Influence of prior knowledge of exercise duration on pacing strategies during game-based activities.

PubMed

Gabbett, Tim J; Walker, Ben; Walker, Shane

2015-04-01

To investigate the influence of prior knowledge of exercise duration on the pacing strategies employed during game-based activities. Twelve semiprofessional team-sport athletes (mean ± SD age 22.8 ± 2.1 y) participated in this study. Players performed 3 small-sided games in random order. In one condition (Control), players were informed that they would play the small-sided game for 12 min and then completed the 12-min game. In a 2nd condition (Deception), players were told that they would play the small-sided game for 6 minutes, but after completing the 6-min game, they were asked to complete another 6 min. In a 3rd condition (Unknown), players were not told how long they would be required to play the small-sided game, but the activity was terminated after 12 min. Movement was recorded using a GPS unit sampling at 10 Hz. Post hoc inspection of video footage was undertaken to count the number of possessions and the number and quality of disposals. Higher initial intensities were observed in the Deception (130.6 ± 3.3 m/min) and Unknown (129.3 ± 2.4 m/min) conditions than the Control condition (123.3 ± 3.4 m/min). Greater amounts of high-speed running occurred during the initial phases of the Deception condition, and more low-speed activity occurred during the Unknown condition. A moderately greater number of total skill involvements occurred in the Unknown condition than the Control condition. These findings suggest that during game-based activities, players alter their pacing strategy based on the anticipated endpoint of the exercise bout.

Efficacy and safety of down-titration versus continuation strategies of biological disease-modifying anti-rheumatic drugs in patients with rheumatoid arthritis with low disease activity or in remission: a systematic review and meta-analysis.

PubMed

Jiang, Mei; Ren, Feifeng; Zheng, Yaning; Yan, Ruyu; Huang, Wenhan; Xia, Ning; Luo, Lei; Zhou, Jun; Tang, Lin

2017-01-01

To evaluate the efficacy and safety of down-titration (dose reduction/tapering) strategies compared with continuation of biological disease-modifying anti-rheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA) who achieved and maintained low disease activity or remission. We searched the following electronic database up to March 2016: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and conference proceedings of the American College of Rheumatology (ACR) and European League against Rheumatism (EULAR). Our meta-analysis included randomized controlled trials (RCTs) of RA patients with low disease activity or in remission that compared down-titration treatment with continuation treatment. Data on flare, defined as a 28-joint Disease Activity Score of ≥3.2, had to have been reported. Outcomes on efficacy or safety were collected. Of 1136 references identified, five RCTs (total, 771 participants) were included. The incidence of disease relapse in the down-titration and continuation groups was similar (risk ratio (RR)=1.14, 95% CI=0.88-1.49). There was no statistical difference in the number of serious adverse events (RR=1.15, 95% CI=0.53-2.49). Withdrawals due to inefficacy or toxicity were similar between groups and no clinically meaningful difference in efficacy outcomes was observed by continuation treatment. Our findings indicated that continuing a standard dose of biological DMARDs in patients with low disease activity conveyed no significant benefit as compared with down-titration therapy, suggesting that a down-titration strategy is as effective as a continuation strategy. Since the number of trials meeting the criteria for this meta-analysis was relatively low, future analyses with additional prospective RCTs are required to compare other biological agents and evaluate the long-term efficacy of these two strategies.

Ultrasound in management of rheumatoid arthritis: ARCTIC randomised controlled strategy trial

PubMed Central

Aga, Anna-Birgitte; Olsen, Inge Christoffer; Lillegraven, Siri; Hammer, Hilde B; Uhlig, Till; Fremstad, Hallvard; Madland, Tor Magne; Lexberg, Åse Stavland; Haukeland, Hilde; Rødevand, Erik; Høili, Christian; Stray, Hilde; Noraas, Anne; Hansen, Inger Johanne Widding; Bakland, Gunnstein; Nordberg, Lena Bugge; van der Heijde, Désirée; Kvien, Tore K

2016-01-01

Objective To determine whether a treatment strategy based on structured ultrasound assessment would lead to improved outcomes in rheumatoid arthritis, compared with a conventional strategy. Design Multicentre, open label, two arm, parallel group, randomised controlled strategy trial. Setting Ten rheumatology departments and one specialist centre in Norway, from September 2010 to September 2015. Participants 238 patients were recruited between September 2010 and April 2013, of which 230 (141 (61%) female) received the allocated intervention and were analysed for the primary outcome. The main inclusion criteria were age 18-75 years, fulfilment of the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for rheumatoid arthritis, disease modifying anti-rheumatic drug naivety with indication for disease modifying drug therapy, and time from first patient reported swollen joint less than two years. Patients with abnormal kidney or liver function or major comorbidities were excluded. Interventions 122 patients were randomised to an ultrasound tight control strategy targeting clinical and imaging remission, and 116 patients were randomised to a conventional tight control strategy targeting clinical remission. Patients in both arms were treated according to the same disease modifying anti-rheumatic drug escalation strategy, with 13 visits over two years. Main outcome measures The primary endpoint was the proportion of patients with a combination between 16 and 24 months of clinical remission, no swollen joints, and non-progression of radiographic joint damage. Secondary outcomes included measures of disease activity, radiographic progression, functioning, quality of life, and adverse events. All participants who attended at least one follow-up visit were included in the full analysis set. Results 26 (22%) of the 118 analysed patients in the ultrasound tight control arm and 21 (19%) of the 112 analysed patients in the clinical tight control arm reached the primary endpoint (mean difference 3.3%, 95% confidence interval −7.1% to 13.7%). Secondary endpoints (disease activity, physical function, and joint damage) were similar between the two groups. Six (5%) patients in the ultrasound tight control arm and seven (6%) patients in the conventional arm had serious adverse events. Conclusions The systematic use of ultrasound in the follow-up of patients with early rheumatoid arthritis treated according to current recommendations is not justified on the basis of the ARCTIC results. The findings highlight the need for randomised trials assessing the clinical application of medical technology. Trial registration Clinical trials NCT01205854. PMID:27530741

Time Out from Tension: Teaching Young Children How To Relax. Teaching Strategies.

ERIC Educational Resources Information Center

Scully, Patricia

2003-01-01

Discusses how using relaxation and stress reduction activities with individual preschool and elementary school-age children during difficult periods can help them regain control, and how integrating relaxation techniques into everyday activities helps to establish positive behavior patterns to support healthy living. Presents breathing activities…

COMPUTATIONAL CHEMISTRY METHOD FOR PREDICTING VAPOR PRESSURES AND ACTIVITY COEFFICIENTS OF POLAR ORGANIC OXYGENATES IN PM2.5

EPA Science Inventory

Parameterizations of interactions of polar multifunctional organic oxygenates in PM2.5 must be included in aerosol chemistry models for evaluating control strategies for reducing ambient concentrations of PM2.5 compounds. Vapor pressures and activity coefficients of these compo...

Metering Best Practices Applied in the National Renewable Energy Laboratory's Research Support Facility: A Primer to the 2011 Measured and Modeled Energy Consumption Datasets

DOE Data Explorer

Sheppy, Michael; Beach, A.; Pless, Shanti

2016-08-09

Modern buildings are complex energy systems that must be controlled for energy efficiency. The Research Support Facility (RSF) at the National Renewable Energy Laboratory (NREL) has hundreds of controllers -- computers that communicate with the building's various control systems -- to control the building based on tens of thousands of variables and sensor points. These control strategies were designed for the RSF's systems to efficiently support research activities. Many events that affect energy use cannot be reliably predicted, but certain decisions (such as control strategies) must be made ahead of time. NREL researchers modeled the RSF systems to predict how they might perform. They then monitor these systems to understand how they are actually performing and reacting to the dynamic conditions of weather, occupancy, and maintenance.

Active suppression of vortex-driven combustion instability using controlled liquid-fuel injection

NASA Astrophysics Data System (ADS)

Pang, Bin

Combustion instabilities remain one of the most challenging problems encountered in developing propulsion and power systems. Large amplitude pressure oscillations, driven by unsteady heat release, can produce numerous detrimental effects. Most previous active control studies utilized gaseous fuels to suppress combustion instabilities. However, using liquid fuel to suppress combustion instabilities is more realistic for propulsion applications. Active instability suppression in vortex-driven combustors using a direct liquid fuel injection strategy was theoretically established and experimentally demonstrated in this dissertation work. Droplet size measurements revealed that with pulsed fuel injection management, fuel droplet size could be modulated periodically. Consequently, desired heat release fluctuation could be created. If this oscillatory heat release is coupled with the natural pressure oscillation in an out of phase manner, combustion instabilities can be suppressed. To identify proper locations of supplying additional liquid fuel for the purpose of achieving control, the natural heat release pattern in a vortex-driven combustor was characterized in this study. It was found that at high Damkohler number oscillatory heat release pattern closely followed the evolving vortex front. However, when Damkohler number became close to unity, heat release fluctuation wave no longer coincided with the coherent structures. A heat release deficit area was found near the dump plane when combustor was operated in lean premixed conditions. Active combustion instability suppression experiments were performed in a dump combustor using a controlled liquid fuel injection strategy. High-speed Schlieren results illustrated that vortex shedding plays an important role in maintaining self-sustained combustion instabilities. Complete combustion instability control requires total suppression of these large-scale coherent structures. The sound pressure level at the excited dominant frequency was reduced by more than 20 dB with controlled liquid fuel injection method. Scaling issues were also investigated in this dump combustor to test the effectiveness of using pulsed liquid fuel injection strategies to suppress instabilities at higher power output conditions. With the liquid fuel injection control method, it was possible to suppress strong instabilities with initial amplitude of +/-5 psi down to the background noise level. The stable combustor operating range was also expanded from equivalence ratio of 0.75 to beyond 0.9.

Flight Test of the F/A-18 Active Aeroelastic Wing Airplane

NASA Technical Reports Server (NTRS)

Clarke, Robert; Allen, Michael J.; Dibley, Ryan P.; Gera, Joseph; Hodgkinson, John

2005-01-01

Successful flight-testing of the Active Aeroelastic Wing airplane was completed in March 2005. This program, which started in 1996, was a joint activity sponsored by NASA, Air Force Research Laboratory, and industry contractors. The test program contained two flight test phases conducted in early 2003 and early 2005. During the first phase of flight test, aerodynamic models and load models of the wing control surfaces and wing structure were developed. Design teams built new research control laws for the Active Aeroelastic Wing airplane using these flight-validated models; and throughout the final phase of flight test, these new control laws were demonstrated. The control laws were designed to optimize strategies for moving the wing control surfaces to maximize roll rates in the transonic and supersonic flight regimes. Control surface hinge moments and wing loads were constrained to remain within hydraulic and load limits. This paper describes briefly the flight control system architecture as well as the design approach used by Active Aeroelastic Wing project engineers to develop flight control system gains. Additionally, this paper presents flight test techniques and comparison between flight test results and predictions.

Virtual Reality to control active participation in a subacute stroke patient during robot-assisted gait training.

PubMed

Bergmann, J; Krewer, C; Müller, F; Koenig, A; Riener, R

2011-01-01

Virtual Reality (VR) provides a promising medium to enrich robot assisted rehabilitation. VR applications present the opportunity to engage patients in therapy and control participation. The aim of this study was to investigate two strategies to control active participation of a stroke patient focusing on the involvement of the paretic leg in task solution. A subacute stroke patient with a severe hemiparesis performed two experiments on the driven gait orthosis Lokomat. Patient activity was quantified by weighted interaction torques measured in both legs (experiment A) and the paretic leg only (experiment B). The patient was able to successfully implement both the bilateral and unilateral control modality. Both control modes increased the motor output of the paretic leg, however the paretic leg control mode resulted in a much more differentiated regulation of the activity in the leg. Both control modes are appropriate approaches to enhance active participation and increase motor output in the paretic leg. Further research should evaluate the therapeutic benefit of patients with hemiparesis using the unilateral control mode depending on the severity of their impairment. © 2011 IEEE

A robust and high-performance queue management controller for large round trip time networks

NASA Astrophysics Data System (ADS)

Khoshnevisan, Ladan; Salmasi, Farzad R.

2016-05-01

Congestion management for transmission control protocol is of utmost importance to prevent packet loss within a network. This necessitates strategies for active queue management. The most applied active queue management strategies have their inherent disadvantages which lead to suboptimal performance and even instability in the case of large round trip time and/or external disturbance. This paper presents an internal model control robust queue management scheme with two degrees of freedom in order to restrict the undesired effects of large and small round trip time and parameter variations in the queue management. Conventional approaches such as proportional integral and random early detection procedures lead to unstable behaviour due to large delay. Moreover, internal model control-Smith scheme suffers from large oscillations due to the large round trip time. On the other hand, other schemes such as internal model control-proportional integral and derivative show excessive sluggish performance for small round trip time values. To overcome these shortcomings, we introduce a system entailing two individual controllers for queue management and disturbance rejection, simultaneously. Simulation results based on Matlab/Simulink and also Network Simulator 2 (NS2) demonstrate the effectiveness of the procedure and verify the analytical approach.

Strategy in short-term memory for pictures in childhood: a near-infrared spectroscopy study.

PubMed

Sanefuji, Masafumi; Takada, Yui; Kimura, Naoko; Torisu, Hiroyuki; Kira, Ryutaro; Ishizaki, Yoshito; Hara, Toshiro

2011-02-01

In Baddeley's working memory model, verbalizable visual material such as pictures are recoded into a phonological form and then rehearsed, while auditory material is rehearsed directly. The recoding and rehearsal processes are mediated by articulatory control process in the left ventrolateral prefrontal cortex (VLPFC). Developmentally, the phonological strategy for serially-presented visual material emerges around 7 years of age, while that for auditory material is consistently present by 4 years of age. However, the strategy change may actually be correlated with memory ability as this usually increases with age. To investigate the relationship between the strategy for pictures and memory ability, we monitored the left VLPFC activation in 5 to 11 year-old children during free recall of visually- or auditorily-presented familiar objects using event-related near-infrared spectroscopy. We hypothesized that the phonological strategy of rehearsal and recoding for visual material would provoke greater activation than only rehearsal for auditory material in the left VLPFC. Therefore, we presumed that the activation difference for visual material compared with auditory material in the left VLPFC may represent the tendency to use a phonological strategy. We found that the activation difference in the left VLPFC showed a significant positive correlation with memory ability but not with age, suggesting that children with high memory ability make more use of phonological strategy for pictures. The present study provides functional evidence that the strategy in short-term memory for pictures shifts gradually from non-phonological to phonological as memory ability increases in childhood. Copyright © 2010 Elsevier Inc. All rights reserved.

Antisense RNA Strategies for Metabolic Engineering of Clostridium acetobutylicum

PubMed Central

Desai, Ruchir P.; Papoutsakis, Eleftherios T.

1999-01-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by ∼100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes. PMID:10049845

Antisense RNA strategies for metabolic engineering of Clostridium acetobutylicum.

PubMed

Desai, R P; Papoutsakis, E T

1999-03-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by approximately 100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes.

Brain-Computer Interface with Inhibitory Neurons Reveals Subtype-Specific Strategies.

PubMed

Mitani, Akinori; Dong, Mingyuan; Komiyama, Takaki

2018-01-08

Brain-computer interfaces have seen an increase in popularity due to their potential for direct neuroprosthetic applications for amputees and disabled individuals. Supporting this promise, animals-including humans-can learn even arbitrary mapping between the activity of cortical neurons and movement of prosthetic devices [1-4]. However, the performance of neuroprosthetic device control has been nowhere near that of limb control in healthy individuals, presenting a dire need to improve the performance. One potential limitation is the fact that previous work has not distinguished diverse cell types in the neocortex, even though different cell types possess distinct functions in cortical computations [5-7] and likely distinct capacities to control brain-computer interfaces. Here, we made a first step in addressing this issue by tracking the plastic changes of three major types of cortical inhibitory neurons (INs) during a neuron-pair operant conditioning task using two-photon imaging of IN subtypes expressing GCaMP6f. Mice were rewarded when the activity of the positive target neuron (N+) exceeded that of the negative target neuron (N-) beyond a set threshold. Mice improved performance with all subtypes, but the strategies were subtype specific. When parvalbumin (PV)-expressing INs were targeted, the activity of N- decreased. However, targeting of somatostatin (SOM)- and vasoactive intestinal peptide (VIP)-expressing INs led to an increase of the N+ activity. These results demonstrate that INs can be individually modulated in a subtype-specific manner and highlight the versatility of neural circuits in adapting to new demands by using cell-type-specific strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Functional localization of a "Time Keeper" function separate from attentional resources and task strategy.

PubMed

Tracy, J I; Faro, S H; Mohamed, F B; Pinsk, M; Pinus, A

2000-03-01

The functional neuroanatomy of time estimation has not been well-documented. This research investigated the fMRI measured brain response to an explicit, prospective time interval production (TIP) task. The study tested for the presence of brain activity reflecting a primary time keeper function, distinct from the brain systems involved either in conscious strategies to monitor time or attentional resource and other cognitive processes to accomplish the task. In the TIP task participants were given a time interval and asked to indicate when it elapsed. Two control tasks (counting forwards, backwards) were administered, in addition to a dual task format of the TIP task. Whole brain images were collected at 1.5 Tesla. Analyses (n = 6) yielded a statistical parametric map (SPM ¿z¿) reflecting time keeping and not strategy (counting, number manipulation) or attention resource utilization. Additional SPM ¿z¿s involving activation associated with the accuracy and magnitude the of time estimation response are presented. Results revealed lateral cerebellar and inferior temporal lobe activation were associated with primary time keeping. Behavioral data provided evidence that the procedures for the explicit time judgements did not occur automatically and utilized controlled processes. Activation sites associated with accuracy, magnitude, and the dual task provided indications of the other structures involved in time estimation that implemented task components related to controlled processing. The data are consistent with prior proposals that the cerebellum is a repository of codes for time processing, but also implicate temporal lobe structures for this type of time estimation task. Copyright 2000 Academic Press.

Fighting food temptations: the modulating effects of short-term cognitive reappraisal, suppression and up-regulation on mesocorticolimbic activity related to appetitive motivation.

PubMed

Siep, Nicolette; Roefs, Anne; Roebroeck, Alard; Havermans, Remco; Bonte, Milene; Jansen, Anita

2012-03-01

The premise of cognitive therapy is that one can overcome the irresistible temptation of highly palatable foods by actively restructuring the way one thinks about food. Testing this idea, participants in the present study were instructed to passively view foods, up-regulate food palatability thoughts, apply cognitive reappraisal (e.g., thinking about health consequences), or suppress food palatability thoughts and cravings. We examined whether these strategies affect self-reported food craving and mesocorticolimbic activity as assessed by functional magnetic resonance imaging. It was hypothesized that cognitive reappraisal would most effectively inhibit the mesocorticolimbic activity and associated food craving as compared to suppression. In addition, it was hypothesized that suppression would lead to more prefrontal cortex activity, reflecting the use of more control resources, as compared to cognitive reappraisal. Self-report results indicated that up-regulation increased food craving compared to the other two conditions, but that there was no difference in craving between the suppression and cognitive reappraisal strategy. Corroborating self-report results, the neuroimaging results showed that up-regulation increased activity in important regions of the mesocorticolimbic circuitry, including the ventral tegmental area, ventral striatum, operculum, posterior insular gyrus, medial orbitofrontal cortex and ventromedial prefrontal cortex. Contrary to our hypothesis, suppression more effectively decreased activity in the core of the mesocorticolimbic circuitry (i.e., ventral tegmental area and ventral striatum) compared to cognitive reappraisal. Overall, the results support the contention that appetitive motivation can be modulated by the application of short-term cognitive control strategies. Copyright © 2012 Elsevier Inc. All rights reserved.

Comparison of various decentralised structural and cavity feedback control strategies for transmitted noise reduction through a double panel structure

NASA Astrophysics Data System (ADS)

Ho, Jen-Hsuan; Berkhoff, Arthur

2014-03-01

This paper compares various decentralised control strategies, including structural and acoustic actuator-sensor configuration designs, to reduce noise transmission through a double panel structure. The comparison is based on identical control stability indexes. The double panel structure consists of two panels with air in between and offers the advantages of low sound transmission at high frequencies, low heat transmission, and low weight. The double panel structure is widely used, such as in the aerospace and automotive industries. Nevertheless, the resonance of the cavity and the poor sound transmission loss at low frequencies limit the double panel's noise control performance. Applying active structural acoustic control to the panels or active noise control to the cavity has been discussed in many papers. In this paper, the resonances of the panels and the cavity are considered simultaneously to further reduce the transmitted noise through an existing double panel structure. A structural-acoustic coupled model is developed to investigate and compare various structural control and cavity control methods. Numerical analysis and real-time control results show that structural control should be applied to both panels. Three types of cavity control sources are presented and compared. The results indicate that the largest noise reduction is obtained with cavity control by loudspeakers modified to operate as incident pressure sources.

Postural strategy and trunk muscle activation during prolonged standing in chronic low back pain patients.

PubMed

Ringheim, Inge; Austein, Helene; Indahl, Aage; Roeleveld, Karin

2015-10-01

Prolonged standing has been associated with development and aggravation of low back pain (LBP). However, the underlying mechanisms are not well known. The aim of the present study was to investigate postural control and muscle activation during and as a result of prolonged standing in chronic LBP (cLBP) patients compared to healthy controls (HCs). Body weight shifts and trunk and hip muscle activity was measured during 15 min standing. Prior and after the standing trial, strength, postural sway, reposition error (RE), flexion relaxation ratio (FRR), and pain were assessed and after the prolonged standing, ratings of perceived exertion. During prolonged standing, the cLBP patients performed significantly more body weight shifts (p<.01) with more activated back and abdominal muscles (p=.01) and similar temporal variability in muscle activation compared to HCs, while the cLBP patients reported more pain and perceived exertion at the end of prolonged standing. Moreover, both groups had a similar change in strength, postural sway, RE and FRR from before to after prolonged standing, where changes in HC were towards pre-standing values of cLBP patients. Thus, despite a more variable postural strategy, the cLBP patients did not have higher muscle activation variability, but a general increased muscle activation level. This may indicate a reduced ability to individually deactivate trunk muscles. Plausibly, due to the increased variable postural strategy, the cLBP patients could compensate for the relatively high muscle activation level, resulting in normal variation in muscle activation and normal reduction in strength, RE and FRR after prolonged standing. Copyright © 2015 Elsevier B.V. All rights reserved.

Inferring strategies for disseminating physical activity policies, programs, and practices from the successes of tobacco control.

PubMed

Green, Lawrence W; Orleans, C Tracy; Ottoson, Judith M; Cameron, Roy; Pierce, John P; Bettinghaus, Erwin P

2006-10-01

Efforts at reducing tobacco use in the United States and Canada over the last half century have been amazingly successful. This article examines those efforts in order to identify policies, programs, and practices found useful in tobacco control that might be usefully disseminated to world populations to improve rates of physical activity. Tobacco-control activities began with efforts to influence the individual smoker through public education and counter-advertising. Increasing awareness of the addictive properties of tobacco, industry efforts to manipulate those properties, and to target youth with aggressive advertising, fueled public outrage that supported additional policy changes to include community interventions, legal actions, and restraints against the tobacco industry. The article first examines ways to view the process of transferring knowledge from one enterprise (reducing tobacco consumption) to another (increasing physical activity). Several theories of knowledge generalization and dissemination are explored: transfer, knowledge utilization, application, diffusion, and implementation. The second section identifies the dissemination of tobacco control by means of brief health behavior-change interventions for smoking cessation that have been successfully integrated into primary clinical care. The question of whether similar strategies can be successfully disseminated to increase physical activity is examined in detail. The article then moves on to look at the success of arguably the most successful program in the world at achieving a reduction in tobacco control-the State of California. Finally, we compare and contrast some of the lessons as they have played out in another national context-Canada. In the concluding section, some lessons are identified that we believe may be successfully utilized in societal attempts to increase physical activity in world populations.

Improving motor activity assessment in depression: which sensor placement, analytic strategy and diurnal time frame are most powerful in distinguishing patients from controls and monitoring treatment effects.

PubMed

Reichert, Markus; Lutz, Alexander; Deuschle, Michael; Gilles, Maria; Hill, Holger; Limberger, Matthias F; Ebner-Priemer, Ulrich W

2015-01-01

Abnormalities in motor activity represent a central feature in major depressive disorder. However, measurement issues are poorly understood, limiting the use of objective measurement of motor activity for diagnostics and treatment monitoring. To improve measurement issues, especially sensor placement, analytic strategies and diurnal effects, we assessed motor activity in depressed patients at the beginning (MD; n=27) and after anti-depressive treatment (MD-post; n=18) as well as in healthy controls (HC; n=16) using wrist- and chest-worn accelerometers. We performed multiple analyses regarding sensor placements, extracted features, diurnal variation, motion patterns and posture to clarify which parameters are most powerful in distinguishing patients from controls and monitoring treatment effects. Whereas most feature-placement combinations revealed significant differences between groups, acceleration (wrist) distinguished MD from HC (d=1.39) best. Frequency (vertical axis chest) additionally differentiated groups in a logistic regression model (R2=0.54). Accordingly, both amplitude (d=1.16) and frequency (d=1.04) showed alterations, indicating reduced and decelerated motor activity. Differences between MD and HC in gestures (d=0.97) and walking (d=1.53) were found by data analysis from the wrist sensor. Comparison of motor activity at the beginning and after MD-treatment largely confirms our findings. Sample size was small, but sufficient for the given effect sizes. Comparison of depressed in-patients with non-hospitalized controls might have limited motor activity differences between groups. Measurement of wrist-acceleration can be recommended as a basic technique to capture motor activity in depressed patients as it records whole body movement and gestures. Detailed analyses showed differences in amplitude and frequency denoting that depressed patients walked less and slower.

Improving Motor Activity Assessment in Depression: Which Sensor Placement, Analytic Strategy and Diurnal Time Frame Are Most Powerful in Distinguishing Patients from Controls and Monitoring Treatment Effects

PubMed Central

Deuschle, Michael; Gilles, Maria; Hill, Holger; Limberger, Matthias F.; Ebner-Priemer, Ulrich W.

2015-01-01

Background Abnormalities in motor activity represent a central feature in major depressive disorder. However, measurement issues are poorly understood, limiting the use of objective measurement of motor activity for diagnostics and treatment monitoring. Methods To improve measurement issues, especially sensor placement, analytic strategies and diurnal effects, we assessed motor activity in depressed patients at the beginning (MD; n=27) and after anti-depressive treatment (MD-post; n=18) as well as in healthy controls (HC; n=16) using wrist- and chest-worn accelerometers. We performed multiple analyses regarding sensor placements, extracted features, diurnal variation, motion patterns and posture to clarify which parameters are most powerful in distinguishing patients from controls and monitoring treatment effects. Results Whereas most feature-placement combinations revealed significant differences between groups, acceleration (wrist) distinguished MD from HC (d=1.39) best. Frequency (vertical axis chest) additionally differentiated groups in a logistic regression model (R2=0.54). Accordingly, both amplitude (d=1.16) and frequency (d=1.04) showed alterations, indicating reduced and decelerated motor activity. Differences between MD and HC in gestures (d=0.97) and walking (d=1.53) were found by data analysis from the wrist sensor. Comparison of motor activity at the beginning and after MD-treatment largely confirms our findings. Limitations Sample size was small, but sufficient for the given effect sizes. Comparison of depressed in-patients with non-hospitalized controls might have limited motor activity differences between groups. Conclusions Measurement of wrist-acceleration can be recommended as a basic technique to capture motor activity in depressed patients as it records whole body movement and gestures. Detailed analyses showed differences in amplitude and frequency denoting that depressed patients walked less and slower. PMID:25885258

The Dutch heart health community intervention 'Hartslag Limburg': results of an effect study at organizational level.

PubMed

Ronda, G; Van Assema, P; Ruland, E; Steenbakkers, M; Van Ree, J; Brug, J

2005-05-01

'Hartslag Limburg', a cardiovascular diseases (CVD) prevention programme, integrates a community strategy and a high-risk strategy to reduce CVD risk behaviours. This article presents the results of the effect evaluation study of the community intervention at the organizational level. Organizational changes were an intermediate goal of the Hartslag Limburg community intervention, as these are assumed to be a prerequisite for changes at the individual level. A baseline-post-test control group design was used. The baseline measurement was conducted in 1998 and the post-test measurement in 2001. At baseline, 700 organizations were selected in the Maastricht region, and 577 in a control region. All organizations that were potentially significant agents in health-promoting activities were included. Data on organizational involvement in health-promoting activities were gathered by means of structured questionnaires, and sent to organization representatives by mail. The overall post-test percentage of organizations involved in at least one activity relating to physical activity was higher in the Maastricht region than in the control region. Furthermore, the number of activities per organization involved in activities relating to healthy eating, smoking behaviour or physical activity was higher in the Maastricht region than in the control region at post-test. This study provided valuable information about organizational involvement in health-promoting activities, as well as important information to consider in future research in this area. Due to the limitations of the study, the importance of measuring change at different social levels in community-based programmes, and the scarcity of effect studies of community interventions at the organizational level, further research on this subject is warranted.

The BLISS cluster randomised controlled trial of the effect of 'active dissemination of information' on standards of care for premature babies in England (BEADI) study protocol [ISRCTN89683698].

PubMed

Acolet, Dominique; Jelphs, Kim; Davidson, Deborah; Peck, Edward; Clemens, Felicity; Houston, Rosie; Weindling, Michael; Lavis, John; Elbourne, Diana

2007-10-08

Gaps between research knowledge and practice have been consistently reported. Traditional ways of communicating information have limited impact on practice changes. Strategies to disseminate information need to be more interactive and based on techniques reported in systematic reviews of implementation of changes. There is a need for clarification as to which dissemination strategies work best to translate evidence into practice in neonatal units across England. The objective of this trial is to assess whether an innovative active strategy for the dissemination of neonatal research findings, recommendations, and national neonatal guidelines is more likely to lead to changes in policy and practice than the traditional (more passive) forms of dissemination in England. Cluster randomised controlled trial of all neonatal units in England (randomised by hospital, n = 182 and stratified by neonatal regional networks and neonatal units level of care) to assess the relative effectiveness of active dissemination strategies on changes in local policies and practices. Participants will be mainly consultant lead clinicians in each unit. The intervention will be multifaceted using: audit and feedback; educational meetings for local staff (evidence-based lectures on selected topics, interactive workshop to examine current practice and draw up plans for change); and quality improvement and organisational changes methods. Policies and practice outcomes for the babies involved will be collected before and after the intervention. Outcomes will assess all premature babies born in England during a three month period for timing of surfactant administration at birth, temperature control at birth, and resuscitation team (qualification and numbers) present at birth.

Modelling and control of solid oxide fuel cell generation system in microgrid

NASA Astrophysics Data System (ADS)

Zhou, Niancheng; Li, Chunyan; Sun, Fangqing; Wang, Qianggang

2017-11-01

Compared with other kinds of fuel cells, solid oxide fuel cell (SOFC) has been widely used in microgrids because of its higher efficiency and longer operation life. The weakness of SOFC lies in its slow response speed when grid disturbance occurs. This paper presents a control strategy that can promote the response speed and limit the fault current impulse for SOFC systems integrated into microgrids. First, the hysteretic control of the bidirectional DC-DC converter, which joins the SOFC and DC bus together, is explored. In addition, an improved droop control with limited current protection is applied in the DC-AC inverter, and the active synchronization control is applied to ensure a smooth transition of the microgrid between the grid-connected mode and the islanded mode. To validate the effectiveness of this control strategy, the control model was built and simulated in PSCAD/EMTDC.

Maintenance of Mitochondrial Oxygen Homeostasis by Cosubstrate Compensation

PubMed Central

Kueh, Hao Yuan; Niethammer, Philipp; Mitchison, Timothy J.

2013-01-01

Mitochondria maintain a constant rate of aerobic respiration over a wide range of oxygen levels. However, the control strategies underlying oxygen homeostasis are still unclear. Using mathematical modeling, we found that the mitochondrial electron transport chain (ETC) responds to oxygen level changes by undergoing compensatory changes in reduced electron carrier levels. This emergent behavior, which we named cosubstrate compensation (CSC), enables the ETC to maintain homeostasis over a wide of oxygen levels. When performing CSC, our ETC models recapitulated a classic scaling relationship discovered by Chance [Chance B (1965) J. Gen. Physiol. 49:163-165] relating the extent of oxygen homeostasis to the kinetics of mitochondrial electron transport. Analysis of an in silico mitochondrial respiratory system further showed evidence that CSC constitutes the dominant control strategy for mitochondrial oxygen homeostasis during active respiration. Our findings indicate that CSC constitutes a robust control strategy for homeostasis and adaptation in cellular biochemical networks. PMID:23528093

Human Papillomavirus Vaccine as an Anti-cancer Vaccine: Collaborative Efforts to Promote HPV Vaccine in the National Comprehensive Cancer Control Program

PubMed Central

Townsend, Julie S.; Steele, C. Brooke; Hayes, Nikki; Bhatt, Achal; Moore, Angela R.

2018-01-01

Background Widespread use of the HPV vaccine has the potential to reduce incidence from HPV-associated cancers. However, vaccine uptake among adolescents remains well below the Healthy People 2020 targets. The Centers for Disease Control and Prevention (CDC)’s National Comprehensive Cancer Control Program awardees (NCCCP) are well positioned to work with immunization programs to increase vaccine uptake. Methods CDC’s chronic disease management information system was queried for objectives and activities associated with HPV vaccine that were reported by NCCCP awardees from 2013 – 2016 as part of program reporting requirements. A content analysis was conducted on the query results to categorize interventions according to strategies outlined in The Guide to Community Preventive Services and the 2014 President’s Cancer Panel report. Results Sixty-two percent of NCCCP awardees had planned or implemented at least one activity since 2013 to address low HPV vaccination coverage in their jurisdictions. Most NCCCP awardees (86%) reported community education activities, while 65% reported activities associated with provider education. Systems-based strategies such as client reminders or provider assessment and feedback were each reported by less than 25% of NCCCP awardees. Conclusion Many NCCCP awardees report planning or implementing activities to address low HPV vaccination coverage, often in conjunction with state immunization programs. NCCCP awardees can play a role in increasing HPV vaccination coverage through their cancer prevention and control expertise and access to partners in the health care community. PMID:28263672

Costs and possible benefits of a two-tier infection control management strategy consisting of active screening for multidrug-resistant organisms and tailored control measures.

PubMed

Mutters, N T; Günther, F; Frank, U; Mischnik, A

2016-06-01

Multidrug-resistant organisms (MDROs) are an economic burden, and infection control (IC) measures are cost- and labour-intensive. A two-tier IC management strategy was developed, including active screening, in order to achieve effective use of limited resources. Briefly, high-risk patients were differentiated from other patients, distinguished according to type of MDRO, and IC measures were implemented accordingly. To evaluate costs and benefits of this IC management strategy. The study period comprised 2.5 years. All high-risk patients underwent microbiological screening. Gram-negative bacteria (GNB) were classified as multidrug-resistant (MDR) and extensively drug-resistant (XDR). Expenses consisted of costs for staff, materials, laboratory, increased workload and occupational costs. In total, 39,551 patients were screened, accounting for 24.5% of all admissions. Of all screened patients, 7.8% (N=3,104) were MDRO positive; these patients were mainly colonized with vancomycin-resistant enterococci (37.3%), followed by meticillin-resistant Staphylococcus aureus (30.3%) and MDR-GNB (28.3%). The median length of stay (LOS) for all patients was 10 days (interquartile range 3-20); LOS was twice as long in colonized patients (P<0.001). Screening costs totalled 255,093.82€, IC measures cost 97,701.36€, and opportunity costs were 599,225.52€. The savings of this IC management strategy totalled 500,941.84€. Possible transmissions by undetected carriers would have caused additional costs of 613,648.90-4,974,939.26€ (i.e. approximately 600,000-5 million €). Although the costs of a two-tier IC management strategy including active microbiological screening are not trivial, these data indicate that the approach is cost-effective when prevented transmissions are included in the cost estimate. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Effects of organic carbon sequestration strategies on soil enzymatic activities

NASA Astrophysics Data System (ADS)

Puglisi, E.; Suciu, N.; Botteri, L.; Ferrari, T.; Coppolecchia, D.; Trevisan, M.; Piccolo, A.

2009-04-01

Greenhouse gases emissions can be counterbalanced with proper agronomical strategies aimed at sequestering carbon in soils. These strategies must be tested not only for their ability in reducing carbon dioxide emissions, but also for their impact on soil quality: enzymatic activities are related to main soil ecological quality, and can be used as early and sensitive indicators of alteration events. Three different strategies for soil carbon sequestration were studied: minimum tillage, protection of biodegradable organic fraction by compost amendment and oxidative polimerization of soil organic matter catalyzed by biometic porfirins. All strategies were compared with a traditional agricultural management based on tillage and mineral fertilization. Experiments were carried out in three Italian soils from different pedo-climatic regions located respectively in Piacenza, Turin and Naples and cultivated with maize or wheat. Soil samples were taken for three consecutive years after harvest and analyzed for their content in phosphates, ß-glucosidase, urease and invertase. An alteration index based on these enzymatic activities levels was applied as well. The biomimetic porfirin application didn't cause changes in enzymatic activities compared to the control at any treatment or location. Enzymatic activities were generally higher in the minimum tillage and compost treatment, while differences between location and date of samplings were limited. Application of the soil alteration index based on enzymatic activities showed that soils treated with compost or subjected to minimum tillage generally have a higher biological quality. The work confirms the environmental sustainability of the carbon sequestering agronomical practices studied.

Active disturbance rejection controller for chemical reactor

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

Both, Roxana; Dulf, Eva H.; Muresan, Cristina I., E-mail: roxana.both@aut.utcluj.ro

2015-03-10

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

A Real-Time Lift Detection Strategy for a Hip Exoskeleton

PubMed Central

Chen, Baojun; Grazi, Lorenzo; Lanotte, Francesco; Vitiello, Nicola; Crea, Simona

2018-01-01

Repetitive lifting of heavy loads increases the risk of back pain and even lumbar vertebral injuries to workers. Active exoskeletons can help workers lift loads by providing power assistance, and therefore reduce the moment and force applied on L5/S1 joint of human body when performing lifting tasks. However, most existing active exoskeletons for lifting assistance are unable to automatically detect user's lift movement, which limits the wide application of active exoskeletons in factories. In this paper, we propose a simple but effective lift detection strategy for exoskeleton control. This strategy uses only exoskeleton integrated sensors, without any extra sensors to capture human motion intentions. This makes the lift detection system more practical for applications in manufacturing environments. Seven healthy subjects participated in this research. Three different sessions were carried out, two for training and one for testing the algorithm. In the two training sessions, subjects were asked to wear a hip exoskeleton, controlled in transparent mode, and perform repetitive lifting and a locomotion circuit; lifting was executed with different techniques. The collected data were used to train the lift detection model. In the testing session, the exoskeleton was controlled in order to deliver torque to assist the lifting action, based on the lift detection made by the trained algorithm. The across-subject average accuracy of lift detection during online test was 97.97 ± 1.39% with subject-dependent model. Offline, the algorithm was trained with data acquired from all subjects to verify its performance for subject-independent detection, and an accuracy of 97.48 ± 1.53% was achieved. In addition, timeliness of the algorithm was quantitatively evaluated and the time delay was <160 ms across different lifting speeds. Surface electromyography was also measured to assess the efficacy of the exoskeleton in assisting subjects in performing load lifting tasks. These results validate the promise of applying the proposed lift detection strategy for exoskeleton control aiming at lift assistance. PMID:29706881

A Real-Time Lift Detection Strategy for a Hip Exoskeleton.

PubMed

Chen, Baojun; Grazi, Lorenzo; Lanotte, Francesco; Vitiello, Nicola; Crea, Simona

2018-01-01

Repetitive lifting of heavy loads increases the risk of back pain and even lumbar vertebral injuries to workers. Active exoskeletons can help workers lift loads by providing power assistance, and therefore reduce the moment and force applied on L5/S1 joint of human body when performing lifting tasks. However, most existing active exoskeletons for lifting assistance are unable to automatically detect user's lift movement, which limits the wide application of active exoskeletons in factories. In this paper, we propose a simple but effective lift detection strategy for exoskeleton control. This strategy uses only exoskeleton integrated sensors, without any extra sensors to capture human motion intentions. This makes the lift detection system more practical for applications in manufacturing environments. Seven healthy subjects participated in this research. Three different sessions were carried out, two for training and one for testing the algorithm. In the two training sessions, subjects were asked to wear a hip exoskeleton, controlled in transparent mode, and perform repetitive lifting and a locomotion circuit; lifting was executed with different techniques. The collected data were used to train the lift detection model. In the testing session, the exoskeleton was controlled in order to deliver torque to assist the lifting action, based on the lift detection made by the trained algorithm. The across-subject average accuracy of lift detection during online test was 97.97 ± 1.39% with subject-dependent model. Offline, the algorithm was trained with data acquired from all subjects to verify its performance for subject-independent detection, and an accuracy of 97.48 ± 1.53% was achieved. In addition, timeliness of the algorithm was quantitatively evaluated and the time delay was <160 ms across different lifting speeds. Surface electromyography was also measured to assess the efficacy of the exoskeleton in assisting subjects in performing load lifting tasks. These results validate the promise of applying the proposed lift detection strategy for exoskeleton control aiming at lift assistance.

A dual-mode disturbance-accommodating controller for the Hubble Space Telescope

NASA Astrophysics Data System (ADS)

Addington, Stewart; Johnson, C. D.

Cyclic thermal expansions and mechanical stiction effects in the Solar Arrays on the Hubble Space Telescope (HST) are triggering repeated occurrences of damped, relaxation-type flex-body vibrations of the solar arrays. Those solar array vibrations are, in turn, causing unwanted, oscillating disturbance torques on the HST main body, which cause unwanted deviations of the telescope from its specified pointing direction. In this paper we propose two strategies one can adopt in designing a telescope-pointing controller to cope with the aforementioned disturbances: (1) a `total isolation' (TI) control strategy whereby the HST controller torques are designed to adaptively counteract and cancel-out the persistent disturbing torques that are causing the unwanted telescope motions, and (2) an `array damping' (AD) control strategy whereby the HST controller torques are used to actively augment the natural dampening of the solar array vibrations and the attendant telescope motions, between triggerings of the stiction-related flex-body relaxation oscillations. Using the principles of Disturbance-Accommodating Control (DAC) Theory a dual-mode controller for a generic, planar-motion (single-axis) model of the HST is proposed. This controller incorporates both the TI and AD modes of disturbance-accommodation. Simulation studies of the closed-loop system using generic parameter values clearly indicate, qualitatively, the enhanced pointing-performance such a controller can achieve.

Effects of Epstein's TARGET on Adolescents' Intentions to Be Physically Active and Leisure-Time Physical Activity

ERIC Educational Resources Information Center

Cecchini, Jose A.; Fernandez-Rio, Javier; Mendez-Gimenez, Antonio

2014-01-01

The aim of this study was to examine the effects of Epstein's TARGET strategies on adolescents' intentions to be physically active and leisure-time physical activity (LTPA) levels. A total of 447 secondary education students (193 females and 254 males), range age 12-17 years, were divided in two groups: control (N = 224) and experimental…

Cognitive deficits are a matter of emotional context: inflexible strategy use mediates context-specific learning impairments in OCD.

PubMed

Zetsche, Ulrike; Rief, Winfried; Westermann, Stefan; Exner, Cornelia

2015-01-01

The present study examines the interplay between cognitive deficits and emotional context in obsessive-compulsive disorder (OCD) and social phobia (SP). Specifically, this study examines whether the inflexible use of efficient learning strategies in an emotional context underlies impairments in probabilistic classification learning (PCL) in OCD, and whether PCL impairments are specific to OCD. Twenty-three participants with OCD, 30 participants with SP and 30 healthy controls completed a neutral and an OCD-specific PCL task. OCD participants failed to adopt efficient learning strategies and showed fewer beneficial strategy switches than controls only in an OCD-specific context, but not in a neutral context. Additionally, OCD participants did not show any explicit memory impairments. Number of beneficial strategy switches in the OCD-specific task mediated the difference in PCL performance between OCD and control participants. Individuals with SP were impaired in both PCL tasks. In contrast to neuropsychological models postulating general cognitive impairments in OCD, the present findings suggest that it is the interaction between cognition and emotion that is impaired in OCD. Specifically, activated disorder-specific fears may impair the flexible adoption of efficient learning strategies and compromise otherwise unimpaired PCL. Impairments in PCL are not specific to OCD.

Drop-on-Demand System for Manufacturing of Melt-based Solid Oral Dosage: Effect of Critical Process Parameters on Product Quality.

PubMed

Içten, Elçin; Giridhar, Arun; Nagy, Zoltan K; Reklaitis, Gintaras V

2016-04-01

The features of a drop-on-demand-based system developed for the manufacture of melt-based pharmaceuticals have been previously reported. In this paper, a supervisory control system, which is designed to ensure reproducible production of high quality of melt-based solid oral dosages, is presented. This control system enables the production of individual dosage forms with the desired critical quality attributes: amount of active ingredient and drug morphology by monitoring and controlling critical process parameters, such as drop size and product and process temperatures. The effects of these process parameters on the final product quality are investigated, and the properties of the produced dosage forms characterized using various techniques, such as Raman spectroscopy, optical microscopy, and dissolution testing. A crystallization temperature control strategy, including controlled temperature cycles, is presented to tailor the crystallization behavior of drug deposits and to achieve consistent drug morphology. This control strategy can be used to achieve the desired bioavailability of the drug by mitigating variations in the dissolution profiles. The supervisor control strategy enables the application of the drop-on-demand system to the production of individualized dosage required for personalized drug regimens.

GHG emissions during the high-rate production of compost using standard and advanced aeration strategies.

PubMed

Puyuelo, B; Gea, T; Sánchez, A

2014-08-01

In this study, we have evaluated different strategies for the optimization of the aeration during the active thermophilic stage of the composting process of source-selected Organic Fraction of Municipal Solid Waste (or biowaste) using reactors at bench scale (50L). These strategies include: typical cyclic aeration, oxygen feedback controller and a new self-developed controller based on the on-line maximization of the oxygen uptake rate (OUR) during the process. Results highlight differences found in the emission of most representative greenhouse gases (GHG) emitted from composting (methane and nitrous oxide) as well as in gases typically related to composting odor problems (ammonia as typical example). Specifically, the cyclic controller presents emissions that can double that of OUR controller, whereas oxygen feedback controller shows a better performance with respect to the cyclic controller. A new parameter, the respiration index efficiency, is presented to quantitatively evaluate the GHG emissions and, in consequence, the main negative environmental impact of the composting process. Other aspects such as the stability of the compost produced and the consumption of resources are also evaluated for each controller. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assist-as-needed path control for the PASCAL rehabilitation robot.

PubMed

Keller, Urs; Rauter, Georg; Riener, Robert

2013-06-01

Adults and children with neurological disorders often require rehabilitation therapy to improve their arm motor functions. Complementary to conventional therapy, robotic therapy can be applied. Such robots should support arm movements while assisting only as much as needed to ensure an active participation of the patient. Different control strategies are known to provide arm support to the patient. The path controller is a strategy that helps the patient's arm to stay close to a given path while allowing for temporal and spatial freedom. In this paper, an assist-as-needed path controller is presented that is implemented in the end-effector-based robot PASCAL, which was designed for children with cerebral palsy. The new control approach is a combination of an existing path controller with additional speed restrictions to support, when the arm speed is too slow, and to resist, when the speed is too fast. Furthermore, a target position gain scheduling is introduced in order to reach a target position with a predefined precision as well as an adaptable direction-dependent supportive flux that supports along the path. These path control features were preliminarily tested with a healthy adult volunteer in different conditions. The presented controller covers the range from a completely passive user, who needs full support to an actively performed movement that needs no assistance. In close future, the controller is planned to be used to enable reaching in children as well as in adults and help to increase the intensity of the rehabilitation therapy by assisting the hand movement and by provoking an active participation.

Mode transition coordinated control for a compound power-split hybrid car

NASA Astrophysics Data System (ADS)

Wang, Chen; Zhao, Zhiguo; Zhang, Tong; Li, Mengna

2017-03-01

With a compound power-split transmission directly connected to the engine in hybrid cars, dramatic fluctuations in engine output torque result in noticeable jerks when the car is in mode transition from electric drive mode to hybrid drive mode. This study designed a mode transition coordinated control strategy, and verified that strategy's effectiveness with both simulations and experiments. Firstly, the mode transition process was analyzed, and ride comfort issues during the mode transition process were demonstrated. Secondly, engine ripple torque was modeled using the measured cylinder pumping pressure when the engine was not in operation. The complete dynamic plant model of the power-split hybrid car was deduced, and its effectiveness was validated by a comparison of experimental and simulation results. Thirdly, a coordinated control strategy was designed to determine the desired engine torque, motor torque, and the moment of fuel injection. Active damping control with two degrees of freedom, based on reference output shaft speed estimation, was designed to mitigate driveline speed oscillations. Carrier torque estimation based on transmission kinematics and dynamics was used to suppress torque disturbance during engine cranking. The simulation and experimental results indicate that the proposed strategy effectively suppressed vehicle jerks and improved ride comfort during mode transition.

Task-Level Strategies for Human Sagittal-Plane Running Maneuvers Are Consistent with Robotic Control Policies

PubMed Central

Qiao, Mu; Jindrich, Devin L.

2012-01-01

The strategies that humans use to control unsteady locomotion are not well understood. A “spring-mass” template comprised of a point mass bouncing on a sprung leg can approximate both center of mass movements and ground reaction forces during running in humans and other animals. Legged robots that operate as bouncing, “spring-mass” systems can maintain stable motion using relatively simple, distributed feedback rules. We tested whether the changes to sagittal-plane movements during five running tasks involving active changes to running height, speed, and orientation were consistent with the rules used by bouncing robots to maintain stability. Changes to running height were associated with changes to leg force but not stance duration. To change speed, humans primarily used a “pogo stick” strategy, where speed changes were associated with adjustments to fore-aft foot placement, and not a “unicycle” strategy involving systematic changes to stance leg hip moment. However, hip moments were related to changes to body orientation and angular speed. Hip moments could be described with first order proportional-derivative relationship to trunk pitch. Overall, the task-level strategies used for body control in humans were consistent with the strategies employed by bouncing robots. Identification of these behavioral strategies could lead to a better understanding of the sensorimotor mechanisms that allow for effective unsteady locomotion. PMID:23284804

[Direccion General de Comunicacion. Programa Nacional de Comunicacion en Poblacion].

PubMed

1988-06-01

Peru's National Population Council is currently developing a national program of population communication. The program will be coordinated with public and private sector activities and will seek help from international organizations. The objective of the program is to promote changes in population knowledge, attitudes, and behaviors in priority social sectors and general public opinion to achieve a better harmony between population growth and distribution and socioeconomic development. The program strategy is to begin with identification of priority audiences. Other components of the strategy include quality control, coordination, decentralization, participation, use of low-cost technologies with high impact, and a multidisciplinary focus. An inventory of institutional activities in population communication will be a major activity.

Transmission of drug-susceptible and drug-resistant tuberculosis and the critical importance of airborne infection control in the era of HIV infection and highly active antiretroviral therapy rollouts.

PubMed

Shenoi, Sheela V; Escombe, A Roderick; Friedland, Gerald

2010-05-15

Comprehensive and successful tuberculosis (TB) care and treatment must incorporate effective airborne infection-control strategies. This is particularly and critically important for health care workers and all persons with or at risk of human immunodeficiency virus (HIV) infection. Past and current outbreaks and epidemics of drug-susceptible, multidrug-resistant, and extensively drug-resistant TB have been fueled by HIV infection, with high rates of morbidity and mortality and linked to the absence or limited application of airborne infection-control strategies in both resource-rich and resource-limited settings. Airborne infection-control strategies are available--grouped into administrative, environmental, and personal protection categories--and have been shown to be associated with decreases in nosocomial transmission of TB; their efficacy has not been fully demonstrated, and their implementation is extremely limited, particularly in resource-limited settings. New research and resources are required to fully realize the potential benefits of infection control in the era of TB and HIV epidemics.

Active vibration control of thin-plate structures with partial SCLD treatment

NASA Astrophysics Data System (ADS)

Lu, Jun; Wang, Pan; Zhan, Zhenfei

2017-02-01

To effectively suppress the low-frequency vibration of a thin-plate, the strategy adopted is to develop a model-based approach to the investigation on the active vibration control of a clamped-clamped plate with partial SCLD treatment. Firstly, a finite element model is developed based on the constitutive equations of elastic, piezoelectric and viscoelastic materials. The characteristics of viscoelastic materials varying with temperature and frequency are described by GHM damping model. A low-dimensional real modal control model which can be used as the basis for active vibration control is then obtained from the combined reduction. The emphasis is placed on the feedback control system to attenuate the vibration of plates with SCLD treatments. A modal controller in conjunction with modal state estimator is designed to solve the problem of full state feedback, making it much more feasible to real-time control. Finally, the theoretical model is verified by modal test, and an active vibration control is validated by hardware-in-the-loop experiment under different external excitations. The numerical and experimental study demonstrate how the piezoelectric actuators actively control the lower modes (first bending and torsional modes) using modal controller, while the higher frequency vibration attenuated by viscoelastic passive damping layer.

Physical activity profiles of U.S. adults trying to lose weight: NHIS 1998.

PubMed

Kruger, Judy; Galuska, Deborah A; Serdula, Mary K; Kohl, Harold W

2005-03-01

Physical activity is an integral part of weight control programs, but recommended amounts vary. The objectives of this study were to describe the prevalence and characteristics of those who reported using exercise as a weight loss strategy (N=14,716), and to determine the prevalence of meeting various institutionally recommended levels of physical activity (N=8538) among that population. Data were obtained from the 1998 National Health Interview Survey, a face-to-face nationally representative household interview. Questions on leisure-time physical activity were analyzed using SUDAAN. Among those who reported trying to lose weight, 55% reported using exercise as a weight loss strategy alone, and of those, 58% reported eating fewer calories. The prevalence of using exercise as a weight loss strategy was directly associated with education and inversely associated with age and body mass index. Among those who reported using exercise as a weight loss strategy, 57% met the minimal 1998 National Institutes of Health recommendation of >or=150 min.wk; 46% met the lower end of the 2001 American College of Sports Medicine recommendation of 200 min.wk; and 30% met the upper end for 300 min.wk. Only 19% met the 2002 Institute of Medicine recommendation of 420 min.wk. Despite the importance of physical activity in a weight loss program, only about half of the persons trying to lose weight reported using exercise. Even among those, only slightly more than half met the minimal recommendations for physical activity. Efforts are needed to aid those trying to lose weight to incorporate appropriate levels of physical activity into their weight loss strategy.

Cognitive control processes in paranoia: the impact of threat induction on strategic cognition and self-focused attention.

PubMed

Flower, Laura; Newman-Taylor, Katherine; Stopa, Lusia

2015-01-01

Current clinical models emphasize certain cognitive processes in the maintenance of distressing paranoia. While a number of these processes have been examined in detail, the role of strategic cognition and self-focused attention remain under-researched. This study examined the deployment of cognitive strategies and self-focused attention in people with non-clinical paranoia. An experimental design was used to examine the impact of a threat activation task on these processes, in participants with high and low non-clinical paranoia. Twenty-eight people were recruited to each group, and completed measures of anxiety, paranoid cognition, strategic cognition and self-focused attention. The threat activation task was effective in increasing anxiety in people with high and low non-clinical paranoia. The high paranoia group experienced more paranoid cognitions following threat activation. This group also reported greater use of thought suppression, punishment and worry, and less use of social control strategies when under threat. No differences were found between the groups on measures of self-focused attention. This study shows that the threat activation task increased anxiety in people with high non-clinical paranoia, leading to increased paranoid thinking. The use of strategic cognition following threat activation varied dependent on level of non-clinical paranoia. If these differences are replicated in clinical groups, the strategies may be implicated in the maintenance of distressing psychosis, and may therefore be a valuable target for therapeutic intervention.

Trainer Interventions as Instructional Strategies in Air Traffic Control Training

ERIC Educational Resources Information Center

Koskela, Inka; Palukka, Hannele

2011-01-01

Purpose: This paper aims to identify methods of guidance and supervision used in air traffic control training. It also aims to show how these methods facilitate trainee participation in core work activities. Design/methodology/approach: The paper applies the tools of conversation analysis and ethnomethodology to explore the ways in which trainers…

DEMONSTRATION OF A PAINT SPRAY BOOTH EMISSION CONTROL STRATEGY USING RECIRCULATION/PARTITIONING & UV/OZONE POLLUTION EMISSION CONTROL - VOLUME 1. TECHNICAL REPORT

EPA Science Inventory

The report describes in detail the source testing, construction, and data reduction/analysis activities that comprise the three phases of a technology demonstration program. Phase I consisted of a detailed baseline evaluation of several paint spray booths operated at the Barstow,...

Neuromuscular mechanisms and neural strategies in the control of time-varying muscle contractions.

PubMed

Erimaki, Sophia; Agapaki, Orsalia M; Christakos, Constantinos N

2013-09-01

The organization of the neural input to motoneurons that underlies time-varying muscle force is assumed to depend on muscle transfer characteristics and neural strategies or control modes utilizing sensory signals. We jointly addressed these interlinked, but previously studied individually and partially, issues for sinusoidal (range 0.5-5.0 Hz) force-tracking contractions of a human finger muscle. Using spectral and correlation analyses of target signal, force signal, and motor unit (MU) discharges, we studied 1) patterns of such discharges, allowing inferences on the motoneuronal input; 2) transformation of MU population activity (EMG) into quasi-sinusoidal force; and 3) relation of force oscillation to target, carrying information on the input's organization. A broad view of force control mechanisms and strategies emerged. Specifically, synchronized MU and EMG modulations, reflecting a frequency-modulated motoneuronal input, accompanied the force variations. Gain and delay drops between EMG modulation and force oscillation, critical for the appropriate organization of this input, occurred with increasing target frequency. According to our analyses, gain compensation was achieved primarily through rhythmical activation/deactivation of higher-threshold MUs and secondarily through the adaptation of the input's strength expected during tracking tasks. However, the input's timing was not adapted to delay behaviors and seemed to depend on the control modes employed. Thus, for low-frequency targets, the force oscillation was highly coherent with, but led, a target, this timing error being compatible with predictive feedforward control partly based on the target's derivatives. In contrast, the force oscillation was weakly coherent, but in phase, with high-frequency targets, suggesting control mainly based on a target's rhythm.

Learning to Listen: Teaching an Active Listening Strategy to Preservice Education Professionals

ERIC Educational Resources Information Center

McNaughton, David; Hamlin, Dawn; McCarthy, John; Head-Reeves, Darlene; Schreiner, Mary

2008-01-01

The importance of parent-teacher communication has been widely recognized; however, there is only limited research on teaching effective listening skills to education professionals. In this study, a pretest-posttest control group design was used to examine the effect of instruction on the active listening skills of preservice education…

Paratransgenic Control of Vector Borne Diseases

PubMed Central

Hurwitz, Ivy; Fieck, Annabeth; Read, Amber; Hillesland, Heidi; Klein, Nichole; Kang, Angray; Durvasula, Ravi

2011-01-01

Conventional methodologies to control vector borne diseases with chemical pesticides are often associated with environmental toxicity, adverse effects on human health and the emergence of insect resistance. In the paratransgenic strategy, symbiotic or commensal microbes of host insects are transformed to express gene products that interfere with pathogen transmission. These genetically altered microbes are re-introduced back to the insect where expression of the engineered molecules decreases the host's ability to transmit the pathogen. We have successfully utilized this strategy to reduce carriage rates of Trypanosoma cruzi, the causative agent of Chagas disease, in the triatomine bug, Rhodnius prolixus, and are currently developing this methodology to control the transmission of Leishmania donovani by the sand fly Phlebotomus argentipes. Several effector molecules, including antimicrobial peptides and highly specific single chain antibodies, are currently being explored for their anti-parasite activities in these two systems. In preparation for eventual field use, we are actively engaged in risk assessment studies addressing the issue of horizontal gene transfer from the modified bacteria to environmental microbes. PMID:22110385

Defects and Interfaces on PtPb Nanoplates Boost Fuel Cell Electrocatalysis.

PubMed

Sun, Yingjun; Liang, Yanxia; Luo, Mingchuan; Lv, Fan; Qin, Yingnan; Wang, Lei; Xu, Chuan; Fu, Engang; Guo, Shaojun

2018-01-01

Nanostructured Pt is the most efficient single-metal catalyst for fuel cell technology. Great efforts have been devoted to optimizing the Pt-based alloy nanocrystals with desired structure, composition, and shape for boosting the electrocatalytic activity. However, these well-known controls still show the limited ability in maximizing the Pt utilization efficiency for achieving more efficient fuel cell catalysis. Herein, a new strategy for maximizing the fuel cell catalysis by controlling/tuning the defects and interfaces of PtPb nanoplates using ion irradiation technique is reported. The defects and interfaces on PtPb nanoplates, controlled by the fluence of incident C + ions, make them exhibit the volcano-like electrocatalytic activity for methanol oxidation reaction (MOR), ethanol oxidation reaction (EOR), and oxygen reduction reaction (ORR) as a function of ion irradiation fluence. The optimized PtPb nanoplates with the mixed structure of dislocations, subgrain boundaries, and small amorphous domains are the most active for MOR, EOR, and ORR. They can also maintain high catalytic stability in acid solution. This work highlights the impact and significance of inducing/controlling the defects and interfaces on Pt-based nanocrystals toward maximizing the catalytic performance by advanced ion irradiation strategy. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Maintaining women's oral health.

PubMed

McCann, A L; Bonci, L

2001-07-01

Women must adopt health-promoting strategies for both general health and the oral cavity, because the health of a woman's body and oral cavity are bidirectional. For general health-maintenance strategies, dental practitioners should actively advise women to minimize alcohol use, abstain from or cease smoking, stay physically active, and choose the right foods to nourish both the body and mind. For oral health-maintenance strategies, dental practitioners should advise women on how to prevent or control oral infections, particularly dental caries and periodontal diseases. Specifically, women need to know how to remove plaque from the teeth mechanically, use appropriate chemotherapeutic agents and dentifrices, use oral irrigation, and control halitosis. Dental practitioners also need to stress the importance of regular maintenance visits for disease prevention. Adolescent women are more prone to gingivitis and aphthous ulcers when they begin their menstrual cycles and need advice about cessation of tobacco use, mouth protection during athletic activities, cleaning orthodontic appliances, developing good dietary habits, and avoiding eating disorders. Women in early to middle adulthood may be pregnant or using oral contraceptives with concomitant changes in oral tissues. Dental practitioners need to advise them how to take care of the oral cavity during these changes and how to promote the health of their infants, including good nutrition. Older women experience the onset of menopause and increased vulnerability to osteoporosis. They may also experience xerostomia and burning mouth syndrome. Dental practitioners need to help women alleviate these symptoms and encourage them to continue good infection control and diet practices.

Engagement Strategies for Self-Monitoring Symptoms of Bipolar Disorder With Mobile and Wearable Technology: Protocol for a Randomized Controlled Trial.

PubMed

Cochran, Amy; Belman-Wells, Livia; McInnis, Melvin

2018-05-10

Monitoring signs and symptoms in bipolar disorder (BP) is typically based on regular assessments from patient-clinician interactions. Mobile and wearable technology promises to make monitoring symptoms in BP easier, but little is known about how best to engage individuals with BP in monitoring symptoms. The objective of this study was to provide the rationale and protocol for a randomized controlled trial that investigates engagement strategies for monitoring symptoms of BP, including the strategies of using activity trackers compared with self-reports and reviewing recorded symptoms weekly with an interviewer. A total of 50 individuals with BP will be recruited from the Prechter Longitudinal Study of Bipolar Disorder at the University of Michigan to participate in a 6-week study. Participants will monitor their symptoms through an activity tracker (Fitbit Alta HR) and a mobile phone app designed for this study. In addition to monitoring symptoms, participants have a 50-50 chance of being assigned to an arm that reviews self-reports and activity information weekly. Statistical tests will be performed to test hypotheses that participants adhere to activity tracking significantly more than self-reporting, prefer activity tracking significantly more than self-reporting, and better adhere to both activity tracking and self-reporting when reviewing collected information weekly. Recruitment commenced in November 2017. The first group of participants began the study in January 2018. This study aims to establish strategies to engage individuals with BP in monitoring their symptoms with mobile and wearable technology. Better engagement strategies are expected to aid current efforts in bipolar research and clinical care, from the development of new mobile phone apps to providing the right intervention to the right individual at the right moment. ClinicalTrials.gov NCT03358238; https://clinicaltrials.gov/ct2/show/NCT03358238 (Archived by WebCite at http://www.webcitation.org/6yebuNfz5). RR1-10.2196/9899. ©Amy Cochran, Livia Belman-Wells, Melvin McInnis. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 10.05.2018.

Active control of sound transmission through partitions composed of discretely controlled modules

NASA Astrophysics Data System (ADS)

Leishman, Timothy W.

This thesis provides a detailed theoretical and experimental investigation of active segmented partitions (ASPs) for the control of sound transmission. ASPs are physically segmented arrays of interconnected acoustically and structurally small modules that are discretely controlled using electronic controllers. Theoretical analyses of the thesis first address physical principles fundamental to ASP modeling and experimental measurement techniques. Next, they explore specific module configurations, primarily using equivalent circuits. Measured normal-incidence transmission losses and related properties of experimental ASPs are determined using plane wave tubes and the two-microphone transfer function technique. A scanning laser vibrometer is also used to evaluate distributed transmitting surface vibrations. ASPs have the inherent potential to provide excellent active sound transmission control (ASTC) through lightweight structures, using very practical control strategies. The thesis analyzes several unique ASP configurations and evaluates their abilities to produce high transmission losses via global minimization of normal transmitting surface vibrations. A novel dual diaphragm configuration is shown to employ this strategy particularly well. It uses an important combination of acoustical actuation and mechano-acoustical segmentation to produce exceptionally high transmission loss (e.g., 50 to 80 dB) over a broad frequency range-including lower audible frequencies. Such performance is shown to be comparable to that produced by much more massive partitions composed of thick layers of steel or concrete and sand. The configuration uses only simple localized error sensors and actuators, permitting effective use of independent single-channel controllers in a decentralized format. This work counteracts the commonly accepted notion that active vibration control of partitions is an ineffective means of controlling sound transmission. With appropriate construction, actuation, and error sensing, ASPs can achieve high sound transmission loss through efficient global control of transmitting surface vibrations. This approach is applicable to a wide variety of source and receiving spaces-and to both near fields and far fields.

Disease activity guided dose reduction and withdrawal of adalimumab or etanercept compared with usual care in rheumatoid arthritis: open label, randomised controlled, non-inferiority trial.

PubMed

van Herwaarden, Noortje; van der Maas, Aatke; Minten, Michiel J M; van den Hoogen, Frank H J; Kievit, Wietske; van Vollenhoven, Ronald F; Bijlsma, Johannes W J; van den Bemt, Bart J F; den Broeder, Alfons A

2015-04-09

To evaluate whether a disease activity guided strategy of dose reduction of two tumour necrosis factor (TNF) inhibitors, adalimumab or etanercept, is non-inferior in maintaining disease control in patients with rheumatoid arthritis compared with usual care. Randomised controlled, open label, non-inferiority strategy trial. Two rheumatology outpatient clinics in the Netherlands, from December 2011 to May 2014. 180 patients with rheumatoid arthritis and low disease activity using adalimumab or etanercept; 121 allocated to the dose reduction strategy, 59 to usual care. Disease activity guided dose reduction (advice to stepwise increase the injection interval every three months, until flare of disease activity or discontinuation) or usual care (no dose reduction advice). Flare was defined as increase in DAS28-CRP (a composite score measuring disease activity) greater than 1.2, or increase greater than 0.6 and current score of at least 3.2. In the case of flare, TNF inhibitor use was restarted or escalated. Difference in proportions of patients with major flare (DAS28-CRP based flare longer than three months) between the two groups at 18 months, compared against a non-inferiority margin of 20%. Secondary outcomes included TNF inhibitor use at study end, functioning, quality of life, radiographic progression, and adverse events. Dose reduction of adalimumab or etanercept was non-inferior to usual care (proportion of patients with major flare at 18 months, 12% v 10%; difference 2%, 95% confidence interval -12% to 12%). In the dose reduction group, TNF inhibitor use could successfully be stopped in 20% (95% confidence interval 13% to 28%), the injection interval successfully increased in 43% (34% to 53%), but no dose reduction was possible in 37% (28% to 46%). Functional status, quality of life, relevant radiographic progression, and adverse events did not differ between the groups, although short lived flares (73% v 27%) and minimal radiographic progression (32% v 15%) were more frequent in dose reduction than usual care. A disease activity guided, dose reduction strategy of adalimumab or etanercept to treat rheumatoid arthritis is non-inferior to usual care with regard to major flaring, while resulting in the successful dose reduction or stopping in two thirds of patients.Trial registration Dutch trial register (www.trialregister.nl), NTR 3216. © van Herwaarden et al 2015.

Engineering Dendritic Cells to Enhance Cancer Immunotherapy

PubMed Central

Boudreau, Jeanette E; Bonehill, Aude; Thielemans, Kris; Wan, Yonghong

2011-01-01

Cancer immunotherapy aims to establish immune-mediated control of tumor growth by priming T-cell responses to target tumor-associated antigens. Three signals are required for T-cell activation: (i) presentation of cognate antigen in self MHC molecules; (ii) costimulation by membrane-bound receptor-ligand pairs; and (iii) soluble factors to direct polarization of the ensuing immune response. The ability of dendritic cells (DCs) to provide all three signals required for T-cell activation makes them an ideal cancer vaccine platform. Several strategies have been developed to enhance and control antigen presentation, costimulation, and cytokine production. In this review, we discuss progress toward developing DC-based cancer vaccines by genetic modification using RNA, DNA, and recombinant viruses. Furthermore, the ability of DC-based vaccines to activate natural killer (NK) and B-cells, and the impact of gene modification strategies on these populations is described. Clinical trials using gene-modified DCs have shown modest results, therefore, further considerations for DC manipulation to enhance their clinical efficacy are also discussed. PMID:21468005

National evaluation of strategies to reduce safety violations for working from heights in construction companies: results from a randomized controlled trial.

PubMed

van der Molen, Henk F; den Herder, Aalt; Warning, Jan; Frings-Dresen, Monique H W

2016-01-09

The objective of this study is to evaluate the effectiveness of a face-to-face strategy and a direct mail strategy on safety violations while working from heights among construction companies compared to a control condition. Construction companies with workers at risk for fall injuries were eligible for this three-armed randomized controlled trial. In total, 27 cities were randomly assigned to intervention groups-where eligible companies were given either a face-to-face guidance strategy or a direct mailing strategy with access to internet facilities-or to a control group. The primary outcomes were the number and type of safety violations recorded by labor inspectors after three months. A process evaluation for both strategies was performed to determine reach, program implementation, satisfaction, knowledge and perceived safety behavior. A cost analysis was performed to establish the financial costs for each intervention strategy. Analyses were done by intention to treat. In total, 41% (n = 88) of the companies eligible for the face-to-face intervention participated and 73% (n = 69) for direct mail. Intervention materials were delivered to 69 % (face-to-face group) and 100 % (direct mail group); completion of intervention activities within companies was low. Satisfaction, increase in knowledge, and safety behavior did not differ between the intervention groups. Costs for personal advice were 28% higher than for direct mail. Ultimately, nine intervention companies were captured in the 288 worksite measurements performed by the labor inspectorate. No statistical differences in mean number of safety violations (1.8-2.4) or penalties (72%-100%) were found between the intervention and control groups based on all worksite inspections. No conclusions about the effect of face-to-face and direct mail strategies on safety violations could be drawn due to the limited number of intervention companies captured in the primary outcome measurements. The costs for a face-to-face strategy are higher compared with a direct mail strategy. No difference in awareness and attitude for safe working was found between employers and workers between both strategies. NTR 4298 on 29-Nov-2013.

A novel asynchronous access method with binary interfaces

PubMed Central

2008-01-01

Background Traditionally synchronous access strategies require users to comply with one or more time constraints in order to communicate intent with a binary human-machine interface (e.g., mechanical, gestural or neural switches). Asynchronous access methods are preferable, but have not been used with binary interfaces in the control of devices that require more than two commands to be successfully operated. Methods We present the mathematical development and evaluation of a novel asynchronous access method that may be used to translate sporadic activations of binary interfaces into distinct outcomes for the control of devices requiring an arbitrary number of commands to be controlled. With this method, users are required to activate their interfaces only when the device under control behaves erroneously. Then, a recursive algorithm, incorporating contextual assumptions relevant to all possible outcomes, is used to obtain an informed estimate of user intention. We evaluate this method by simulating a control task requiring a series of target commands to be tracked by a model user. Results When compared to a random selection, the proposed asynchronous access method offers a significant reduction in the number of interface activations required from the user. Conclusion This novel access method offers a variety of advantages over traditionally synchronous access strategies and may be adapted to a wide variety of contexts, with primary relevance to applications involving direct object manipulation. PMID:18959797

Age-specific strategies for immunization reminders and recalls: a registry-based randomized trial.

PubMed

Dombkowski, Kevin J; Costello, Lauren E; Harrington, Laura B; Dong, Shiming; Kolasa, Maureen; Clark, Sarah J

2014-07-01

Although previous studies have found reminder/recall to be effective in increasing immunization rates, little guidance exists regarding the specific ages at which it is optimal to send reminder/recall notices. To assess the relative effectiveness of centralized reminder/recall strategies targeting age-specific vaccination milestones among children in urban areas during June 2008-June 2009. Three reminder/recall strategies used capabilities of the Michigan Care Improvement Registry (MCIR), a statewide immunization information system: a 7-month recall strategy, a 12-month reminder strategy, and a 19-month recall strategy. Eligible children were randomized to notification (intervention) or no notification groups (control). Primary study outcomes included MCIR-recorded immunization activity (administration of ≥1 new dose, entry of ≥1 historic dose, entry of immunization waiver) within 60 days following each notification cycle. A total of 10,175 children were included: 2,072 for the 7-month recall, 3,502 for the 12-month reminder, and 4,601 for the 19-month recall. Immunization activity was similar between notification versus no notification groups at both 7 and 12 months. Significantly more 19-month-old children in the recall group (26%) had immunization activity compared to their counterparts who did not receive a recall notification (19%). Although recall notifications can positively affect immunization activity, the effect may vary by targeted age group. Many 7- and 12-month-olds had immunization activity following reminder/recall; however, levels of activity were similar irrespective of notification, suggesting that these groups were likely to receive medical care or immunization services without prompting. Copyright © 2014 American Journal of Preventive Medicine. All rights reserved.

Antibody-Based Preventive and Therapeutic Strategies Against HIV.

PubMed

Fabra-Garcia, Amanda; Beltran, Carolina; Sanchez-Merino, Victor; Yuste, Eloisa

2016-01-01

Over the years, numerous studies have been carried out demonstrating the role of antibodies in HIV control leading to the development of antibody-based therapeutic and prophylactic strategies. The objective of this review is to provide updated information on the role of antibodies in the prevention and control of HIV infection and the strategies against HIV that have been designed based on this information. Passive transfer of anti-HIV antibodies in animal models has proven the efficacy of certain antibodies in the prevention and treatment of infection. The capacity of antibodies to control the virus was first attributed to their neutralizing capacity. However, we now know that there are other Fc-mediated antibody activities associated with virus protection. When it comes to better understanding protection against HIV, we ought to pay particular attention to mucosal immune responses. The evidence accumulated so far indicates that an effective vaccine against HIV should generate both mucosal IgAs and systemic IgGs. Due to the problematic induction of protective anti-HIV antibodies, several groups have developed alternative approaches based on antibody delivery via gene therapy vectors. Experiments in animal models with these vectors have shown impressive protection levels and this strategy is now being clinically trialed. Taking into account all the information included in this review, it seems evident that anti-HIV-1 antibodies play an important role in virus control and prevention. This review aims to give an overview of the strategies used and the advances in antibody-based preventive and therapeutic strategies against HIV-1.

An aeration control strategy for oxidation ditch processes based on online oxygen requirement estimation.

PubMed

Zhan, J X; Ikehata, M; Mayuzumi, M; Koizumi, E; Kawaguchi, Y; Hashimoto, T

2013-01-01

A feedforward-feedback aeration control strategy based on online oxygen requirements (OR) estimation is proposed for oxidation ditch (OD) processes, and it is further developed for intermittent aeration OD processes, which are the most popular type in Japan. For calculating OR, concentrations of influent biochemical oxygen demand (BOD) and total Kjeldahl nitrogen (TKN) are estimated online by the measurement of suspended solids (SS) and sometimes TKN is estimated by NH4-N. Mixed liquor suspended solids (MLSS) and temperature are used to estimate the required oxygen for endogenous respiration. A straightforward parameter named aeration coefficient, Ka, is introduced as the only parameter that can be tuned automatically by feedback control or manually by the operators. Simulation with an activated sludge model was performed in comparison to fixed-interval aeration and satisfying result of OR control strategy was obtained. The OR control strategy has been implemented at seven full-scale OD plants and improvements in nitrogen removal are obtained in all these plants. Among them, the results obtained in Yumoto wastewater treatment plant were presented, in which continuous aeration was applied previously. After implementing intermittent OR control, the total nitrogen concentration was reduced from more than 5 mg/L to under 2 mg/L, and the electricity consumption was reduced by 61.2% for aeration or 21.5% for the whole plant.

Multi-objective optimisation of wastewater treatment plant control to reduce greenhouse gas emissions.

PubMed

Sweetapple, Christine; Fu, Guangtao; Butler, David

2014-05-15

This study investigates the potential of control strategy optimisation for the reduction of operational greenhouse gas emissions from wastewater treatment in a cost-effective manner, and demonstrates that significant improvements can be realised. A multi-objective evolutionary algorithm, NSGA-II, is used to derive sets of Pareto optimal operational and control parameter values for an activated sludge wastewater treatment plant, with objectives including minimisation of greenhouse gas emissions, operational costs and effluent pollutant concentrations, subject to legislative compliance. Different problem formulations are explored, to identify the most effective approach to emissions reduction, and the sets of optimal solutions enable identification of trade-offs between conflicting objectives. It is found that multi-objective optimisation can facilitate a significant reduction in greenhouse gas emissions without the need for plant redesign or modification of the control strategy layout, but there are trade-offs to consider: most importantly, if operational costs are not to be increased, reduction of greenhouse gas emissions is likely to incur an increase in effluent ammonia and total nitrogen concentrations. Design of control strategies for a high effluent quality and low costs alone is likely to result in an inadvertent increase in greenhouse gas emissions, so it is of key importance that effects on emissions are considered in control strategy development and optimisation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Modeling, Analysis and Mitigation of Sub-Synchronous Interactions between Full- and Partial-Scale Voltage-Source Converters and Power Networks

NASA Astrophysics Data System (ADS)

Alawasa, Khaled Mohammad

Voltage-source converters (VSCs) have gained widespread acceptance in modern power systems. The stability and dynamics of power systems involving these devices have recently become salient issues. In the small-signal sense, the dynamics of VSC-based systems is dictated by its incremental output impedance, which is formed by a combination of 'passive' circuit components and 'active' control elements. Control elements such as control parameters, control loops, and control topologies play a significant role in shaping the impedance profile. Depending on the control schemes and strategies used, VSC-based systems can exhibit different incremental impedance dynamics. As the control elements and dynamics are involved in the impedance structure, the frequency-dependent output impedance might have a negative real-part (i.e., a negative resistance). In the grid-connected mode, the negative resistance degrades the system damping and negatively impacts the stability. In high-voltage networks where high-power VSC-based systems are usually employed and where sub-synchronous dynamics usually exist, integrating large VSC-based systems might reduce the overall damping and results in unstable dynamics. The objectives of this thesis are to (1) investigate and analyze the output impedance properties under different control strategies and control functions, (2) identify and characterize the key contributors to the impedance and sub-synchronous damping profiles, and (3) propose mitigation techniques to minimize and eliminate the negative impact associated with integrating VSC-based systems into power systems. Different VSC configurations are considered in this thesis; in particular, the full-scale and partial-scale topologies (doubly fed-induction generators) are addressed. Additionally, the impedance and system damping profiles are studied under two different control strategies: the standard vector control strategy and the recently-developed power synchronization control strategy. Furthermore, this thesis proposes a simple and robust technique for damping the sub-synchronous resonance in a power system.

Socio-Ecological Intervention to Promote Active Commuting to Work: Protocol and Baseline Findings of a Cluster Randomized Controlled Trial in Finland

PubMed Central

Aittasalo, Minna; Tiilikainen, Johanna; Tokola, Kari; Seimelä, Timo; Sarjala, Satu-Maaria; Metsäpuro, Pasi; Suni, Jaana; Vähä-Ypyä, Henri; Vaismaa, Kalle; Vakkala, Olli; Foster, Charlie; Titze, Sylvia; Vasankari, Tommi

2017-01-01

Active commuting to work (ACW) is beneficial to traffic, environment and population health. More evidence is needed on effective ways to promote ACW. This paper describes the protocol and baseline findings of a cluster-randomized controlled study, which aims to promote ACW with multilevel strategies in two large workplace areas in Tampere, Finland. In Phase 1, the impacts of environmental strategies (trail improvements) were evaluated in 11 workplaces within Area 1. In Phase 2, five more workplaces were recruited from Area 2 to evaluate the impacts of social and behavioral strategies customized for each workplace. For this purpose, the workplaces in both areas were randomly assigned into experimental group (EXP, n = 6 + 2), which promoted ACW with social and behavioral strategies or into comparison group (COM, n = 5 + 3), which participated in the data collection only. The primary indicator in both phases is the change in employees’ ACW. Secondary indicators are e.g., changes in employees’ self-rated health, wellbeing at work, restrictions to and motivation for ACW, adverse effects due to ACW and the use and quality of the main walking and cycling trails. Also process, efficiency and environmental evaluation is included. The study is the first one in Finland to combine interdisciplinary collaboration between practitioners and researchers working in the fields of transportation, urban design, physical activity and sustainable development to promote ACW. The findings benefit all stakeholders interested in promoting ACW in urban context.

Monitoring lipase/esterase activity by stopped flow in a sequential injection analysis system using p-nitrophenyl butyrate.

PubMed

Pliego, Jorge; Mateos, Juan Carlos; Rodriguez, Jorge; Valero, Francisco; Baeza, Mireia; Femat, Ricardo; Camacho, Rosa; Sandoval, Georgina; Herrera-López, Enrique J

2015-01-27

Lipases and esterases are biocatalysts used at the laboratory and industrial level. To obtain the maximum yield in a bioprocess, it is important to measure key variables, such as enzymatic activity. The conventional method for monitoring hydrolytic activity is to take out a sample from the bioreactor to be analyzed off-line at the laboratory. The disadvantage of this approach is the long time required to recover the information from the process, hindering the possibility to develop control systems. New strategies to monitor lipase/esterase activity are necessary. In this context and in the first approach, we proposed a lab-made sequential injection analysis system to analyze off-line samples from shake flasks. Lipase/esterase activity was determined using p-nitrophenyl butyrate as the substrate. The sequential injection analysis allowed us to measure the hydrolytic activity from a sample without dilution in a linear range from 0.05-1.60 U/mL, with the capability to reach sample dilutions up to 1000 times, a sampling frequency of five samples/h, with a kinetic reaction of 5 min and a relative standard deviation of 8.75%. The results are promising to monitor lipase/esterase activity in real time, in which optimization and control strategies can be designed.

Monitoring Lipase/Esterase Activity by Stopped Flow in a Sequential Injection Analysis System Using p-Nitrophenyl Butyrate

PubMed Central

Pliego, Jorge; Mateos, Juan Carlos; Rodriguez, Jorge; Valero, Francisco; Baeza, Mireia; Femat, Ricardo; Camacho, Rosa; Sandoval, Georgina; Herrera-López, Enrique J.

2015-01-01

Lipases and esterases are biocatalysts used at the laboratory and industrial level. To obtain the maximum yield in a bioprocess, it is important to measure key variables, such as enzymatic activity. The conventional method for monitoring hydrolytic activity is to take out a sample from the bioreactor to be analyzed off-line at the laboratory. The disadvantage of this approach is the long time required to recover the information from the process, hindering the possibility to develop control systems. New strategies to monitor lipase/esterase activity are necessary. In this context and in the first approach, we proposed a lab-made sequential injection analysis system to analyze off-line samples from shake flasks. Lipase/esterase activity was determined using p-nitrophenyl butyrate as the substrate. The sequential injection analysis allowed us to measure the hydrolytic activity from a sample without dilution in a linear range from 0.05–1.60 U/mL, with the capability to reach sample dilutions up to 1000 times, a sampling frequency of five samples/h, with a kinetic reaction of 5 min and a relative standard deviation of 8.75%. The results are promising to monitor lipase/esterase activity in real time, in which optimization and control strategies can be designed. PMID:25633600

Malignant vagotonia due to selective baroreflex failure

NASA Technical Reports Server (NTRS)

Jordan, J.; Shannon, J. R.; Black, B. K.; Costa, F.; Ertl, A. C.; Furlan, R.; Biaggioni, I.; Robertson, D.

1997-01-01

Baroreflex failure is characterized by dramatic fluctuations of sympathetic activity and paroxysms of hypertension and tachycardia. In contrast, unopposed parasympathetic activity has not been described in patients with baroreflex failure because of concurrent parasympathetic denervation of the heart. We describe the unusual case of a patient with baroreflex failure in a setting of preserved parasympathetic control of HR manifesting episodes of severe bradycardia and asystole. Thus, parasympathetic control of the HR may be intact in occasional patients with baroreflex failure. Patients with this selective baroreflex failure require a unique therapeutic strategy for the control of disease manifestations.

The Marulu Strategy 2008-2012: overcoming Fetal Alcohol Spectrum Disorder (FASD) in the Fitzroy Valley.

PubMed

Fitzpatrick, James P; Oscar, June; Carter, Maureen; Elliott, Elizabeth J; Latimer, Jane; Wright, Edie; Boulton, John

2017-10-01

Aboriginal leaders concerned about high rates of Fetal Alcohol Spectrum Disorder (FASD) in the Fitzroy Valley, remote north-western Australia, introduced restrictions on access to take-away full-strength alcohol. Following this, Aboriginal leaders engaged strategic partners in a broader strategy to address FASD in the region. The aim of this study was to develop and implement a community-led, researcher-supported, FASD strategy. A review of literature focusing on community-led FASD strategies identified key components that informed the Marulu FASD strategy. These included strategy ownership, leadership, and governance by participating communities, and a research framework. Community meetings and workshops led to the development of The Marulu FASD Strategy (2008). Feasibility and community consent to conduct a FASD prevalence study (the Lililwan Project) was confirmed, and implementation was progressed (2010-2013). Concurrent FASD prevention activities were conducted. In 2012, the Marulu FASD Unit was established within a local Aboriginal organisation to sustain and coordinate ongoing strategy activities. Community control of public health initiatives can be achieved when Aboriginal communities prioritise issues of significant concern, and engage strategic partners to overcome them. Implications for public health: The Marulu Strategy forms a template for action to address FASD and other public health issues in Aboriginal communities in Australia and internationally. © 2017 The Authors.

Evaluating landfill aftercare strategies: A life cycle assessment approach.

PubMed

Turner, David A; Beaven, Richard P; Woodman, Nick D

2017-05-01

This study investigates the potential impacts caused by the loss of active environmental control measures during the aftercare period of landfill management. A combined mechanistic solute flow model and life cycle assessment (LCA) approach was used to evaluate the potential impacts of leachate emissions over a 10,000year time horizon. A continuum of control loss possibilities occurring at different times and for different durations were investigated for four different basic aftercare scenarios, including a typical aftercare scenario involving a low permeability cap and three accelerated aftercare scenarios involving higher initial infiltration rates. Assuming a 'best case' where control is never lost, the largest potential impacts resulted from the typical aftercare scenario. The maximum difference between potential impacts from the 'best case' and the 'worst case', where control fails at the earliest possible point and is never reinstated, was only a fourfold increase. This highlights potential deficiencies in standard life cycle impact assessment practice, which are discussed. Nevertheless, the results show how the influence of active control loss on the potential impacts of landfilling varies considerably depending on the aftercare strategy used and highlight the importance that leachate treatment efficiencies have upon impacts. Copyright © 2016 Elsevier Ltd. All rights reserved.

Integrated Attitude Control Strategy for the Asteroid Redirect Mission

NASA Technical Reports Server (NTRS)

Lopez, Pedro, Jr.; Price, Hoppy; San Martin, Miguel

2014-01-01

A deep-space mission has been proposed to redirect an asteroid to a distant retrograde orbit around the moon using a robotic vehicle, the Asteroid Redirect Vehicle (ARV). In this orbit, astronauts will rendezvous with the ARV using the Orion spacecraft. The integrated attitude control concept that Orion will use for approach and docking and for mated operations will be described. Details of the ARV's attitude control system and its associated constraints for redirecting the asteroid to the distant retrograde orbit around the moon will be provided. Once Orion is docked to the ARV, an overall description of the mated stack attitude during all phases of the mission will be presented using a coordinate system that was developed for this mission. Next, the thermal and power constraints of both the ARV and Orion will be discussed as well as how they are used to define the optimal integrated stack attitude. Lastly, the lighting and communications constraints necessary for the crew's extravehicular activity planned to retrieve samples from the asteroid will be examined. Similarly, the joint attitude control strategy that employs both the Orion and the ARV attitude control assets prior, during, and after each extravehicular activity will also be thoroughly discussed.

An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions.

PubMed

Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M

2017-01-01

In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method.

An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions

PubMed Central

Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M.

2017-01-01

In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method. PMID:28192436

Using the CDC's Worksite Health ScoreCard as a Framework to Examine Worksite Health Promotion and Physical Activity.

PubMed

Gutermuth, Leah K; Hager, Erin R; Pollack Porter, Keshia

2018-06-21

Worksite health promotion programs are emerging as an effective approach for addressing the adult obesity epidemic and improving the overall health of employees. We conducted a scoping review to identify articles that described a physical activity component (eg, promoted increased physical or reduced sitting time) of a worksite health promotion intervention. Our search specified full-length articles published in English from January 2000 through July 2015. We used the Centers for Disease Control and Prevention's Worksite Health ScoreCard, a validated tool, as a framework to summarize information on organizational supports strategies (18 questions) and physical activity strategies (9 questions) implemented by worksite health promotion programs. We also determined whether or not the included studies reported significant (P < .05) improvements in physical activity. We identified 18 worksite health promotion programs; 11 produced significant improvements in physical activity. Incentives, health risk assessments, health promotion committees, leadership support, marketing, and subsidies or discounts for use of exercise facilities were the most effective organizational supports strategies cited, and physical activity seminars, classes, and workshops were the most effective physical activity strategies cited. The use of the Health ScoreCard allowed for a practical interpretation of our findings, which can inform next steps for the field. Future research should explore the relationships between components of worksite health promotion programs and their outcomes to further develop best practices that can improve worker health and promote physical activity.

Altered strategy in short-term memory for pictures in children with attention-deficit/hyperactivity disorder: a near-infrared spectroscopy study.

PubMed

Sanefuji, Masafumi; Yamashita, Hiroshi; Torisu, Hiroyuki; Takada, Yui; Imanaga, Hisako; Matsunaga, Mayumi; Ishizaki, Yoshito; Sakai, Yasunari; Yoshida, Keiko; Hara, Toshiro

2014-07-30

Strategy in short-term memory for serially presented pictures shifts gradually from a non-phonological to a phonological method as memory ability increases during typical childhood development. However, little is known about the development of this strategic change in children with attention-deficit/hyperactivity disorder (ADHD). To understand the neural basis of ADHD, we investigated short-term memory strategies using near-infrared spectroscopy. ADHD children aged from 6 to 12 years and age- and sex-matched control children were assessed in this study. Regional activity was monitored in the left ventrolateral prefrontal cortex to assess strategies used during short-term memory for visual or phonological objects. We examined the hypothesis that the strategic methods used would be correlated with memory ability. Higher memory ability and the phonological strategy were significantly correlated in the control group but not in the ADHD group. Intriguingly, ADHD children receiving methylphenidate treatment exhibited increased use of phonological strategy compared with those without. In conclusion, we found evidence of an altered strategy in short-term memory in ADHD children. The modulatory effect of methylphenidate indicates its therapeutic efficacy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Development of tools to study personal weight control strategies: OxFAB taxonomy

PubMed Central

Aveyard, Paul; Koshiaris, Constantinos; Jebb, Susan A.

2016-01-01

Objective To describe the development of the Oxford Food and Activity Behaviors (OxFAB) taxonomy and questionnaire to explore the cognitive and behavioral strategies used by individuals during weight management attempts. Methods The taxonomy was constructed through a qualitative analysis of existing resources and a review of existing behavior change taxonomies and theories. The taxonomy was translated into a questionnaire to identify strategies used by individuals. Think‐aloud interviews were conducted to test the face/concept validity of the questionnaire, and test–retest reliability was assessed in a sample of 138 participants. Results The OxFAB taxonomy consists of 117 strategies grouped into 23 domains. Compared to taxonomies used to describe interventions, around half of the domains and strategies identified are unique to the OxFAB taxonomy. The OxFAB questionnaire consists of 117 questions, one for each strategy from the taxonomy. Test–retest resulted in a mean PABAK score of 0.61 (SD 0.15). Questions were revised where appropriate. Conclusions The OxFAB taxonomy and questionnaire provide a conceptual framework to identify the cognitive and behavioral strategies used by individuals during attempts at weight control. PMID:26748902

Development of tools to study personal weight control strategies: OxFAB taxonomy.

PubMed

Hartmann-Boyce, Jamie; Aveyard, Paul; Koshiaris, Constantinos; Jebb, Susan A

2016-02-01

To describe the development of the Oxford Food and Activity Behaviors (OxFAB) taxonomy and questionnaire to explore the cognitive and behavioral strategies used by individuals during weight management attempts. The taxonomy was constructed through a qualitative analysis of existing resources and a review of existing behavior change taxonomies and theories. The taxonomy was translated into a questionnaire to identify strategies used by individuals. Think-aloud interviews were conducted to test the face/concept validity of the questionnaire, and test-retest reliability was assessed in a sample of 138 participants. The OxFAB taxonomy consists of 117 strategies grouped into 23 domains. Compared to taxonomies used to describe interventions, around half of the domains and strategies identified are unique to the OxFAB taxonomy. The OxFAB questionnaire consists of 117 questions, one for each strategy from the taxonomy. Test-retest resulted in a mean PABAK score of 0.61 (SD 0.15). Questions were revised where appropriate. The OxFAB taxonomy and questionnaire provide a conceptual framework to identify the cognitive and behavioral strategies used by individuals during attempts at weight control. © 2016 The Authors. Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).

WWTP dynamic disturbance modelling--an essential module for long-term benchmarking development.

PubMed

Gernaey, K V; Rosen, C; Jeppsson, U

2006-01-01

Intensive use of the benchmark simulation model No. 1 (BSM1), a protocol for objective comparison of the effectiveness of control strategies in biological nitrogen removal activated sludge plants, has also revealed a number of limitations. Preliminary definitions of the long-term benchmark simulation model No. 1 (BSM1_LT) and the benchmark simulation model No. 2 (BSM2) have been made to extend BSM1 for evaluation of process monitoring methods and plant-wide control strategies, respectively. Influent-related disturbances for BSM1_LT/BSM2 are to be generated with a model, and this paper provides a general overview of the modelling methods used. Typical influent dynamic phenomena generated with the BSM1_LT/BSM2 influent disturbance model, including diurnal, weekend, seasonal and holiday effects, as well as rainfall, are illustrated with simulation results. As a result of the work described in this paper, a proposed influent model/file has been released to the benchmark developers for evaluation purposes. Pending this evaluation, a final BSM1_LT/BSM2 influent disturbance model definition is foreseen. Preliminary simulations with dynamic influent data generated by the influent disturbance model indicate that default BSM1 activated sludge plant control strategies will need extensions for BSM1_LT/BSM2 to efficiently handle 1 year of influent dynamics.

A pilot study examining the effects of priming headache illness schema on attentional engagement towards pain relief medication, in those with high and low medication treatment beliefs.

PubMed

Ahluwalia, Monisha; Hughes, Alicia M; McCracken, Lance M; Chilcot, Joseph

2017-08-01

Few studies have assessed the underlying theoretical components of the Common Sense Model. Past studies have found, through implicit priming, that coping strategies are embedded within illness schema. Our aim was to evaluate the effect priming 'headache' illness schema upon attentional engagement to pain relief medication and to examine the interaction with illness treatment beliefs. Attentional engagement to the pain relief medication ('Paracetamol') was assessed using a 2 (primed vs. control) × 2 (strong belief in medication efficacy vs. weak belief in medication efficacy) design. During a grammatical decision task (identifying verbs/non-verbs), participants were randomised to receive a headache prime or a control. Response latency to the target word, 'Paracetamol' was the dependent variable. 'Paracetamol' treatment beliefs were determined using the brief illness perception questionnaire. Sixty-three participants completed the experiment. There was a significant interaction between illness-primed vs. control and high vs. low treatment efficacy of Paracetamol (p < .001), suggesting an attentional disengagement effect to the coping strategy in illness-primed participants whom held stronger treatment beliefs regarding the efficacy of Paracetamol. In summary, implicit illness schema activation may simultaneously activate embedded coping strategies, which appears to be moderated by specific illness beliefs.

Facet‐Controlled Synthetic Strategy of Cu2O‐Based Crystals for Catalysis and Sensing

PubMed Central

Shang, Yang

2015-01-01

Shape‐dependent catalysis and sensing behaviours are primarily focused on nanocrystals enclosed by low‐index facets, especially the three basic facets ({100}, {111}, and {110}). Several novel strategies have recently exploded by tailoring the original nanocrystals to greatly improve the catalysis and sensing performances. In this Review, we firstly introduce the synthesis of a variety of Cu2O nanocrystals, including the three basic Cu2O nanocrystals (cubes, octahedra and rhombic dodecahedra, enclosed by the {100}, {111}, and {110} facets, respectively), and Cu2O nanocrystals enclosed by high‐index planes. We then discuss in detail the three main facet‐controlled synthetic strategies (deposition, etching and templating) to fabricate Cu2O‐based nanocrystals with heterogeneous, etched, or hollow structures, including a number of important concepts involved in those facet‐controlled routes, such as the selective adsorption of capping agents for protecting special facets, and the impacts of surface energy and active sites on reaction activity trends. Finally, we highlight the facet‐dependent properties of the Cu2O and Cu2O‐based nanocrystals for applications in photocatalysis, gas catalysis, organocatalysis and sensing, as well as the relationship between their structures and properties. We also summarize and comment upon future facet‐related directions. PMID:27980909

Facet-Controlled Synthetic Strategy of Cu2O-Based Crystals for Catalysis and Sensing.

PubMed

Shang, Yang; Guo, Lin

2015-10-01

Shape-dependent catalysis and sensing behaviours are primarily focused on nanocrystals enclosed by low-index facets, especially the three basic facets ({100}, {111}, and {110}). Several novel strategies have recently exploded by tailoring the original nanocrystals to greatly improve the catalysis and sensing performances. In this Review, we firstly introduce the synthesis of a variety of Cu 2 O nanocrystals, including the three basic Cu 2 O nanocrystals (cubes, octahedra and rhombic dodecahedra, enclosed by the {100}, {111}, and {110} facets, respectively), and Cu 2 O nanocrystals enclosed by high-index planes. We then discuss in detail the three main facet-controlled synthetic strategies (deposition, etching and templating) to fabricate Cu 2 O-based nanocrystals with heterogeneous, etched, or hollow structures, including a number of important concepts involved in those facet-controlled routes, such as the selective adsorption of capping agents for protecting special facets, and the impacts of surface energy and active sites on reaction activity trends. Finally, we highlight the facet-dependent properties of the Cu 2 O and Cu 2 O-based nanocrystals for applications in photocatalysis, gas catalysis, organocatalysis and sensing, as well as the relationship between their structures and properties. We also summarize and comment upon future facet-related directions.

Activation of AMP-activated protein kinase in the liver: a new strategy for the management of metabolic hepatic disorders

PubMed Central

Viollet, Benoit; Foretz, Marc; Guigas, Bruno; Horman, Sandrine; Dentin, Renaud; Bertrand, Luc; Hue, Louis; Andreelli, Fabrizio

2006-01-01

It is now becoming evident that the liver has an important role in the control of whole body metabolism of energy nutrients. In this review, we focus on recent findings showing that AMP-activated protein kinase (AMPK) plays a major role in the control of hepatic metabolism. AMPK integrates nutritional and hormonal signals to promote energy balance by switching on catabolic pathways and switching off ATP-consuming pathways, both by short-term effects on phosphorylation of regulatory proteins and by long-term effects on gene expression. Activation of AMPK in the liver leads to the stimulation of fatty acid oxidation and inhibition of lipogenesis, glucose production and protein synthesis. Medical interest in the AMPK system has recently increased with the demonstration that AMPK could mediate some of the effects of the fat cell-derived adiponectin and the antidiabetic drugs metformin and thiazolidinediones. These findings reinforce the idea that pharmacological activation of AMPK may provide, through signalling and metabolic and gene expression effects, a new strategy for the management of metabolic hepatic disorders linked to type 2 diabetes and obesity. PMID:16644802

Research on Robust Control Strategies for VSC-HVDC

NASA Astrophysics Data System (ADS)

Zhu, Kaicheng; Bao, Hai

2018-01-01

In the control system of VSC-HVDC, the phase locked loop provides phase signals to voltage vector control and trigger pulses to generate the required reference phase. The PLL is a typical second-order system. When the system is in unstable state, it will oscillate, make the trigger angle shift, produce harmonic, and make active power and reactive power coupled. Thus, considering the external disturbances introduced by the PLL in VSC-HVDC control system, the parameter perturbations of the controller and the model uncertainties, a H∞ robust controller of mixed sensitivity optimization problem is designed by using the Hinf function provided by the robust control toolbox. Then, compare it with the proportional integral controller through the MATLAB simulation experiment. By contrast, when the H∞ robust controller is added, active and reactive power of the converter station can track the change of reference values more accurately and quickly, and reduce overshoot. When the step change of active and reactive power occurs, mutual influence is reduced and better independent regulation is achieved.

Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats.

PubMed

Lalanza, Jaume F; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M

2015-11-05

Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders.

Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats

PubMed Central

Lalanza, Jaume F.; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M.

2015-01-01

Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders. PMID:26538081

Predictors of response to pain management treatment. The role of family environment and changes in cognitive processes.

PubMed

Tota-Faucette, M E; Gil, K M; Williams, D A; Keefe, F J; Goli, V

1993-06-01

The purpose of the present study was to examine factors that influence individual differences in treatment response after multidisciplinary pain management. Pre-post assessment design. 119 chronic pain inpatients. Outcome measures included pain report from the McGill Pain Questionnaire, emotional distress from the Symptom Checklist-90 Revised, and activity discomfort from the Activity Discomfort Scale. Process measures included the Family Environment Scale, the Coping Strategies Questionnaire, and the Inventory of Negative Thoughts in Response to Pain. Results indicated that pretreatment family environment, cognitive coping strategies, and negative thinking accounted for small yet significant proportions of the variance in outcome. The proportion of variance accounted for by the changes in cognitive coping and negative thinking was somewhat higher. An increase in pain control and rational thinking was related to decreases in depression and anxiety, pain report, and activity discomfort. Decreases in negative social cognitions were related to decreased depression at posttreatment. Changes in coping strategies and negative thinking may be important mechanisms related to improvement, or lack of improvement, in a range of outcome measures. Patients from families who are controlling and disorganized, and patients high on negative thinking at pretreatment may represent high-risk groups in need of further individually tailored interventions.

Ride performance of a high speed rail vehicle using controlled semi active suspension system

NASA Astrophysics Data System (ADS)

Sharma, Sunil Kumar; Kumar, Anil

2017-05-01

The rail-wheel interaction in a rail vehicle running at high speed results in large amplitude vibration of carbody that deteriorates the ride comfort of travellers. The role of suspension system is crucial to provide an acceptable level of ride performance. In this context, an existing rail vehicle is modelled in vertical, pitch and roll motions of carbody and bogies. Additionally, nonlinear stiffness and damping parameters of passive suspension system are defined based on experimental data. In the secondary vertical suspension system, a magneto-rheological (MR) damper is included to improve the ride quality and comfort. The parameters of MR damper depend on the current, amplitude and frequency of excitations. At different running speeds, three semi-active suspension strategies with MR damper are analysed for periodic track irregularity and the resulting performance indices are juxtaposed with the nonlinear passive suspension system. The disturbance rejection and force tracking damper controller algorithms are applied to control the desired force of MR damper. This study reveals that the vertical vibrations of a vehicle can be reduced significantly by using the proposed semi-active suspension strategies. Moreover, it naturally results in improved ride quality and passenger’s comfort in comparison to the existing passive system.

Recruiting seniors with chronic low back pain for a randomized controlled trial of a self-management program.

PubMed

Groupp, Elyse; Haas, Mitchell; Fairweather, Alisa; Ganger, Bonnie; Attwood, Michael

2005-02-01

To identify recruitment challenges and elucidate specific strategies that enabled recruitment of seniors for a randomized trial on low back pain comparing the Chronic Disease Self-management Program of the Stanford University to a 6-month wait-list control group. Recruitment for a randomized controlled trial. Community-based program offered at 12 locations. Community-dwelling seniors 60 years and older with chronic low back pain of mechanical origin. Passive recruitment strategies included advertisement in local and senior newspapers, in senior e-mail newsletters and listservs, in local community centers and businesses. Active strategies included meeting seniors at health fairs, lectures to the public and organizational meetings, and the help of trusted professionals in the community. A total of 100 white and 20 African American seniors were recruited. The program seemed to have the most appeal to white, middle-class older adults, educated through high school level. Advertisement failed to attract any participants to the program. Successful strategies included interaction with seniors at health fairs and lectures on health care, especially when the program was endorsed by a trusted community professional. Generating interest in the self-management program required keen communication skills because the idea of "self-management" was met with a myriad of responses, ranging from disinterest to disbelief. Generating interest also required active participation within the communities. Initial contacts had to be established with trusted professionals, whose endorsement enabled the project managers to present the concept of self-management to the seniors. More complex recruitment strategies were required for this study involving the self-management approach to back pain than for studies involving treatment.

Altered muscle recruitment during extension from trunk flexion in low back pain developers.

PubMed

Nelson-Wong, Erika; Alex, Brendan; Csepe, David; Lancaster, Denver; Callaghan, Jack P

2012-12-01

A functionally induced, transient low back pain model consisting of exposure to prolonged standing has been used to elucidate baseline neuromuscular differences between previously asymptomatic individuals classified as pain developers and non-pain developers based on their pain response during a standing exposure. Previous findings have included differences in frontal plane lumbopelvic control and altered movement strategies that are present prior to pain development. Control strategies during sagittal plane movement have not been previously investigated in this sample. The purpose of this research was to investigate neuromuscular control differences during the extension phase from trunk flexion between pain developers and non-pain developers. Continuous electromyography and kinematic data were collected during standing trunk flexion and extension on 43 participants (22 male) with an age range of 18-33 years, prior to entering into the prolonged standing exposure. Participants were classified as pain developer/non-pain developer by their pain response (≥ 10 mm increase on a 100 mm visual analog scale) during standing. Relative timing and sequencing data between muscle pairs were calculated through cross-correlation analyses, and evaluated by group and gender. Pain developers demonstrated a 'top-down' muscle recruitment strategy with lumbar extensors activated prior to gluteus maximus, while non-pain developers demonstrated a typical 'bottom-up' muscle recruitment strategy with gluteus maximus activated prior to lumbar extensors. Individuals predisposed to low back pain development during standing exhibited altered neuromuscular strategies prior to pain development. These findings may help to characterize biomechanical movement profiles that could be important for early identification of people at risk for low back pain. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tunable riboregulator switches for post-transcriptional control of gene expression

DOE PAGES

Krishnamurthy, Malathy; Hennelly, Scott Patrick; Dale, Taraka T.; ...

2015-07-13

The most straightforward approach to altering the flux through a particular metabolic step is to increase or decrease the concentration of the enzyme catalyst. Until recently engineering strategies for altering gene expression have focused on transcription control using strong inducible promoters or by using one of several strategies to knock down or knock out a wasteful gene. Recently, synthetic riboregulators have been developed for translational regulation of gene expression. We report a new modular synthetic riboregulator class that has the potential to finely tune protein expression and independently control the concentration of each enzyme in an engineered metabolic pathway. Ourmore » design includes a cis-repressor at the 5’ end of the mRNA that forms a stem-loop helix occluding the ribosome binding site and blocking translation. An activating-RNA, expressed in trans, frees the RBS turning on translation. The overall architecture of the riboregulators is designed using Watson-Crick base-pairing stability followed by directed evolution on a portion of each trans-activator to fine tune translation. We report a cis-repressor that can completely shut off translation of antibiotic resistance reporters and a trans-activator that restores translation. We have shown it is possible to use riboregulators to achieve translational control of gene expression over a wide dynamic range. Using a bioluminescent reporter system, we demonstrated an ON/OFF ratio >300. We have demonstrated that a targeting sequence can be changed to develop riboregulators that can independently regulate translation of many genes with minimal cross-talk. In a SELEX experiment, we demonstrated that by subtly altering the sequence of the trans-activator, it is possible to alter the equilibrium between repressed and activated states and achieve intermediate translational control.« less

Circulating Magnetic Microbubbles for Localized Real-Time Control of Drug Delivery by Ultrasonography-Guided Magnetic Targeting and Ultrasound

PubMed Central

Chertok, Beata; Langer, Robert

2018-01-01

Image-guided and target-selective modulation of drug delivery by external physical triggers at the site of pathology has the potential to enable tailored control of drug targeting. Magnetic microbubbles that are responsive to magnetic and acoustic modulation and visible to ultrasonography have been proposed as a means to realize this drug targeting strategy. To comply with this strategy in vivo, magnetic microbubbles must circulate systemically and evade deposition in pulmonary capillaries, while also preserving magnetic and acoustic activities in circulation over time. Unfortunately, challenges in fabricating magnetic microbubbles with such characteristics have limited progress in this field. In this report, we develop magnetic microbubbles (MagMB) that display strong magnetic and acoustic activities, while also preserving the ability to circulate systemically and evade pulmonary entrapment. Methods: We systematically evaluated the characteristics of MagMB including their pharmacokinetics, biodistribution, visibility to ultrasonography and amenability to magneto-acoustic modulation in tumor-bearing mice. We further assessed the applicability of MagMB for ultrasonography-guided control of drug targeting. Results: Following intravenous injection, MagMB exhibited a 17- to 90-fold lower pulmonary entrapment compared to previously reported magnetic microbubbles and mimicked circulation persistence of the clinically utilized Definity microbubbles (>10 min). In addition, MagMB could be accumulated in tumor vasculature by magnetic targeting, monitored by ultrasonography and collapsed by focused ultrasound on demand to activate drug deposition at the target. Furthermore, drug delivery to target tumors could be enhanced by adjusting the magneto-acoustic modulation based on ultrasonographic monitoring of MagMB in real-time. Conclusions: Circulating MagMB in conjunction with ultrasonography-guided magneto-acoustic modulation may provide a strategy for tailored minimally-invasive control over drug delivery to target tissues. PMID:29290812

Designing a Gunnery Training Strategy

DTIC Science & Technology

1990-06-01

more direct test of the effects of subgoal commonality would not compare part and whole training; it would instead compare groups whose training is...speech production, and musical performance is that a higher level of control determines the nature of a given activity, while a lower level governs the...necessarily correspond to successive training requisites. In fact, Hoffman et al. (1983) compared top-down and bottom-up training strategies using similar

Patient-centered recruitment and retention for a randomized controlled study.

PubMed

Chhatre, Sumedha; Jefferson, Ashlie; Cook, Ratna; Meeker, Caitlin R; Kim, Ji Hyun; Hartz, Kayla Marie; Wong, Yu-Ning; Caruso, Adele; Newman, Diane K; Morales, Knashawn H; Jayadevappa, Ravishankar

2018-03-27

Recruitment and retention strategies for patient-centered outcomes research are evolving and research on the subject is limited. In this work, we present a conceptual model of patient-centered recruitment and retention, and describe the recruitment and retention activities and related challenges in a patient-centered comparative effectiveness trial. This is a multicenter, longitudinal randomized controlled trial in localized prostate cancer patients. We recruited 743 participants from three sites over 15 months period (January 2014 to March 2015), and followed them for 24 months. At site 1, of the 773 eligible participants, 551 (72%) were enrolled. At site 2, 34 participants were eligible and 23 (68%) enrolled. Of the 434 eligible participants at site 3, 169 (39%) enrolled. We observed that strategies related to the concepts of trust (e.g., physician involvement, ensuring protection of information), communication (e.g., brochures and pamphlets in physicians' offices, continued contact during regular clinic visits and calling/emailing assessment), attitude (e.g., emphasizing the altruistic value of research, positive attitude of providers and research staff), and expectations (e.g., full disclosure of study requirements and time commitment, update letters) facilitated successful patient recruitment and retention. A stakeholders' advisory board provided important input for the recruitment and retention activities. Active engagement, reminders at the offices, and personalized update letters helped retention during follow-up. Usefulness of telephone recruitment was site specific and, at one site, the time requirement for telephone recruitment was a challenge. We have presented multilevel strategies for successful recruitment and retention in a clinical trial using a patient-centered approach. Our strategies were flexible to accommodate site-level requirements. These strategies as well as the challenges can aid recruitment and retention efforts of future large-scale, patient-centered research studies. Clinicaltrials.gov , ID: NCT02032550 . Registered on 22 November 2013.

Managing Air Quality - Program Implementation

EPA Pesticide Factsheets

Describes elements for the set of activities to ensure that control strategies are put into effect and that air quality goals and standards are fulfilled, permitting programs, and additional resources related to implementation under the Clean Air Act.

Dietary habits and weight maintenance success in high versus low exercisers in the National Weight Control Registry

PubMed Central

Ogden, Lorraine G.; Phelan, Suzanne; Thomas, J. Graham; Hill, James O; Wing, Rena R.; Wyatt, Holly R.

2015-01-01

Background The National Weight Control Registry (NWCR) was established to examine characteristics of successful weight loss maintainers. This study compares the diet and behavioral characteristics and weight regain trajectories of NWCR members with differing physical activity (PA) levels at baseline. Methods Participants (n=3591) were divided into 4 levels of self-reported PA at registry entry (<1000, 1000 to <2250, 2250 to <3500, and ≥3500 kcals/week). We compared self-reported energy intake (EI), macronutrient composition, eating behaviors (dietary restraint, hunger, and disinhibition), weight loss maintenance strategies, and 3 year weight regain between these 4 activity groups. Results Those with the highest PA at registry entry had lost the most weight, and reported lower fat intake, more dietary restraint, and greater reliance on several specific dietary strategies to maintain weight loss. Those in the lowest PA category maintained weight loss despite low levels of PA and without greater reliance on dietary strategies. There were no differences in odds of weight regain at year 3 between PA groups. Conclusions These findings suggest that there is not a “one size fits all strategy” for successful weight loss maintenance and that weight loss maintenance may require the use of more strategies by some individuals than others. PMID:24385447

Actively Controlling Buffet-Induced Excitations

NASA Technical Reports Server (NTRS)

Moses, Robert W.; Pototzky, Anthony S.; Henderson, Douglas A.; Galea, Stephen C.; Manokaran, Donald S.; Zimcik, David G.; Wickramasinghe, Viresh; Pitt, Dale M.; Gamble, Michael A.

2005-01-01

High performance aircraft, especially those with twin vertical tails, encounter unsteady buffet loads when flying at high angles of attack. These loads result in significant random stresses, which may cause fatigue damage leading to restricted capabilities and availability of the aircraft. An international collaborative research activity among Australia, Canada and the United States, conducted under the auspices of The Technical Cooperation Program (TTCP) contributed resources toward a program that coalesced a broad range of technical knowledge and expertise into a single investigation to demonstrate the enhanced performance and capability of the advanced active BLA control system in preparation for a flight test demonstration. The research team investigated the use of active structural control to alleviate the damaging structural response to these loads by applying advanced directional piezoelectric actuators, the aircraft rudder, switch mode amplifiers, and advanced control strategies on an F/A-18 aircraft empennage. Some results of the full-scale investigation are presented herein.

Gait post-stroke: Pathophysiology and rehabilitation strategies.

PubMed

Beyaert, C; Vasa, R; Frykberg, G E

2015-11-01

We reviewed neural control and biomechanical description of gait in both non-disabled and post-stroke subjects. In addition, we reviewed most of the gait rehabilitation strategies currently in use or in development and observed their principles in relation to recent pathophysiology of post-stroke gait. In both non-disabled and post-stroke subjects, motor control is organized on a task-oriented basis using a common set of a few muscle modules to simultaneously achieve body support, balance control, and forward progression during gait. Hemiparesis following stroke is due to disruption of descending neural pathways, usually with no direct lesion of the brainstem and cerebellar structures involved in motor automatic processes. Post-stroke, improvements of motor activities including standing and locomotion are variable but are typically characterized by a common postural behaviour which involves the unaffected side more for body support and balance control, likely in response to initial muscle weakness of the affected side. Various rehabilitation strategies are regularly used or in development, targeting muscle activity, postural and gait tasks, using more or less high-technology equipment. Reduced walking speed often improves with time and with various rehabilitation strategies, but asymmetric postural behaviour during standing and walking is often reinforced, maintained, or only transitorily decreased. This asymmetric compensatory postural behaviour appears to be robust, driven by support and balance tasks maintaining the predominant use of the unaffected side over the initially impaired affected side. Based on these elements, stroke rehabilitation including affected muscle strengthening and often stretching would first need to correct the postural asymmetric pattern by exploiting postural automatic processes in various particular motor tasks secondarily beneficial to gait. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Family planning to promote physical activity: a randomized controlled trial protocol.

PubMed

Quinlan, Alison; Rhodes, Ryan E; Blanchard, Chris M; Naylor, Patti-Jean; Warburton, Darren E R

2015-10-05

Physical activity is associated with the reduction of several chronic conditions in adults. Additionally, physical activity is extremely important for children for their development and cognitive functioning and also to create a physically active lifestyle that continues into adulthood. Despite the known benefits of physical activity, only one in five adults are achieving the public health recommendations of 150 minutes of moderate-to-vigorous physical activity per week and only 13 % of boys and 6 % of girls between the ages of 5 and 17 years are meeting the guidelines of 60 minutes per day. This study aims to evaluate whether a planning condition improves adherence to regular physical activity compared to an education-only control condition among families. Families are eligible if there is at least one child between the ages of 6 and 12 years who is not meeting the Canadian Physical Activity Guidelines. A six-month longitudinal randomized controlled trial will be used to compare the two conditions. Materials will be delivered at baseline with 'booster' sessions at six weeks and three months. Participants will be assessed at baseline and at six months with a fitness test, as well as questionnaires and accelerometery at baseline, six weeks, three months and six months. A total of 137 families have been recruited thus far from Greater Victoria. This study is ongoing and recruitment will continue until December 2015 with the target goal of reaching 160 families. This protocol describes the implementation of a randomized controlled trial that utilizes planning strategies to try and increase physical activity among families. Research findings could be useful in public health in providing effective strategies to families to help decrease sedentary lifestyles. Additionally, findings may help to inform future interventions aimed at increasing physical activity among families. This trial was registered on June 5, 2012 with the Clinical Trials Registry maintained by the National Library of Medicine at the National Institutes of Health. The registration ID is NCT01882192.

Shoulder motor performance assessment in the sagittal plane in children with hemiplegia during single joint pointing tasks.

PubMed

Formica, Domenico; Petrarca, Maurizio; Rossi, Stefano; Zollo, Loredana; Guglielmelli, Eugenio; Cappa, Paolo

2014-07-29

Pointing is a motor task extensively used during daily life activities and it requires complex visuo-motor transformation to select the appropriate movement strategy. The study of invariant characteristics of human movements has led to several theories on how the brain solves the redundancy problem, but the application of these theories on children affected by hemiplegia is limited. This study aims at giving a quantitative assessment of the shoulder motor behaviour in children with hemiplegia during pointing tasks. Eight children with hemiplegia were involved in the study and were asked to perform movements on the sagittal plane with both arms, at low and high speed. Subject movements were recorded using an optoelectronic system; a 4-DOF model of children arm has been developed to calculate kinematic and dynamic variables. A set of evaluation indexes has been extracted in order to quantitatively assess whether and how children modify their motor control strategies when perform movements with the more affected or less affected arm. In low speed movements, no differences can be seen in terms of movement duration and peak velocity between the More Affected arm (MA) and the Less Affected arm (LA), as well as in the main characteristics of movement kinematics and dynamics. As regards fast movements, remarkable differences in terms of strategies of motor control can be observed: while movements with LA did not show any significant difference in Dimensionless Jerk Index (JI) and Dimensionless Torque-change Cost index (TC) between the elevation and lowering phases, suggesting that motor control optimization is similar for movements performed with or against gravity, movements with MA showed a statistically significant increase of both JI and TC during lowering phase. Results suggest the presence of a different control strategy for fast movements in particular during lowering phase. Results suggest that motor control is not able to optimize Jerk and Torque-change cost functions in the same way when controls the two arms, suggesting that children with hemiplegia do not actively control MA lowering fast movements, in order to take advantage of the passive inertial body properties, rather than to attempt its optimal control.

Design of control-group conditions in clinical trials of behavioral interventions.

PubMed

Lindquist, Ruth; Wyman, Jean F; Talley, Kristine M C; Findorff, Mary J; Gross, Cynthia R

2007-01-01

To review considerations in the design of placebo (attention) control conditions for community-based clinical trials of health behavior change interventions and to provide practical strategies for the design of control conditions. A well-designed control condition is an essential component of a clinical trial to foster the unambiguous interpretation of study findings. Pitfalls in the design of control conditions in clinical trials of behavioral interventions are identified and strategies to address them are offered. Types of control conditions that have been used in fall prevention trials are described, along with their strengths and weaknesses. The control condition used in the recent fall evaluation and prevention program (FEPP) was designed to overcome limitations of previous trial designs; it is provided to illustrate how to apply specific design principles. Pitfalls in the design of behavioral intervention studies may be avoided with the application of sound design principles. The FEPP active control condition can be used as a model in the design of future studies.

Effects of Epstein's TARGET on adolescents' intentions to be physically active and leisure-time physical activity.

PubMed

Cecchini, Jose A; Fernandez-Rio, Javier; Mendez-Gimenez, Antonio

2014-06-01

The aim of this study was to examine the effects of Epstein's TARGET strategies on adolescents' intentions to be physically active and leisure-time physical activity (LTPA) levels. A total of 447 secondary education students (193 females and 254 males), range age 12-17 years, were divided in two groups: control (N = 224) and experimental (N = 223). Epstein's TARGET strategies were applied by especially trained teachers only to the experimental group in their physical education (PE) classes during 12 consecutive weeks. Participants' intentions to be physically active and their LTPA levels were assessed prior to the intervention (pre), at the end of it (post-1) and 3 months after the intervention (post-2). Significant increases were observed only in the experimental group in post-1 and post-2 on both variables. PE interventions based on TARGET strategies seem to be effective increasing adolescents' intentions to be physically active, as well as time spent in LTPA. As most adolescents participate in PE, these interventions could lead to substantial public health benefits. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

An fMRI study into emotional processing in Parkinson's disease: Does increased medial prefrontal activation compensate for striatal dysfunction?

PubMed

Moonen, Anja J H; Weiss, Peter H; Wiesing, Michael; Weidner, Ralph; Fink, Gereon R; Reijnders, Jennifer S A M; Weber, Wim M; Leentjens, Albert F G

2017-01-01

Apart from a progressive decline of motor functions, Parkinson's disease (PD) is also characterized by non-motor symptoms, including disturbed processing of emotions. This study aims at assessing emotional processing and its neurobiological correlates in PD with the focus on how medicated Parkinson patients may achieve normal emotional responsiveness despite basal ganglia dysfunction. Nineteen medicated patients with mild to moderate PD (without dementia or depression) and 19 matched healthy controls passively viewed positive, negative, and neutral pictures in an event-related blood oxygen level-dependent functional magnetic resonance imaging study (BOLD-fMRI). Individual subjective ratings of valence and arousal levels for these pictures were obtained right after the scanning. Parkinson patients showed similar valence and arousal ratings as controls, denoting intact emotional processing at the behavioral level. Yet, Parkinson patients showed decreased bilateral putaminal activation and increased activation in the right dorsomedial prefrontal cortex (PFC), compared to controls, both most pronounced for highly arousing emotional stimuli. Our findings revealed for the first time a possible compensatory neural mechanism in Parkinson patients during emotional processing. The increased medial PFC activity may have modulated emotional responsiveness in patients via top-down cognitive control, therewith restoring emotional processing at the behavioral level, despite striatal dysfunction. These results may impact upon current treatment strategies of affective disorders in PD as patients may benefit from this intact or even compensatory influence of prefrontal areas when therapeutic strategies are applied that rely on cognitive control to modulate disturbed processing of emotions.

Governing board structure, business strategy, and performance of acute care hospitals: a contingency perspective.

PubMed Central

Young, G; Beekun, R I; Ginn, G O

1992-01-01

Contingency theory suggests that for a hospital governing board to be effective in taking on a more active role in strategic management, the board needs to be structured to complement the overall strategy of the organization. A survey study was conducted to examine the strategies of acute care hospitals as related to the structural characteristics of their governing boards. After controlling for organizational size and system membership, results indicated a significant relationship between the governing board structure of 109 acute care hospitals and their overall business strategy. Strategy also accounted for more of the variance in board structure than either organization size or system membership. Finally, the greater the match between board structure and hospital strategy, the stronger the hospitals' financial performance. PMID:1399656

Vascular endothelium summary statement II: Cardiovascular disease prevention and control.

PubMed

Mensah, George A; Ryan, Una S; Hooper, W Craig; Engelgau, Michael M; Callow, Allan D; Kapuku, Gaston K; Mantovani, Alberto

2007-05-01

The prevention and control of cardiovascular disease (CVD), principally ischemic heart disease and stroke, are a major clinical and public health challenge. Worldwide, CVD accounts for substantial morbidity and mortality. The major modifiable CVD risk factors are known and all of them cause endothelial activation and dysfunction. Preventing and controlling the established risk factors are associated with preserved endothelial function and reduced risk of CVD. Research advances that improve our understanding of strategies to preserve endothelial function or make the endothelial cells resilient to environmental insults may help improve our preventive interventions. This summary statement addresses the current state of the science with respect to endothelial dysfunction and CVD pathogenesis, diagnostic evaluation, and suggested strategies for public health practice and research.

WFIRST: Managing Telescope Wavefront Stability to Meet Coronagraph Performance

NASA Astrophysics Data System (ADS)

Noecker, Martin; Poberezhskiy, Ilya; Kern, Brian; Krist, John; WFIRST System Engineering Team

2018-01-01

The WFIRST coronagraph instrument (CGI) needs a stable telescope and active wavefront control to perform coronagraph science with an expected sensitivity of 8x10-9 in the exoplanet-star flux ratio (SNR=10) at 200 milliarcseconds angular separation. With its subnanometer requirements on the stability of its input wavefront error (WFE), the CGI employs a combination of pointing and wavefront control loops and thermo-mechanical stability to meet budget allocations for beam-walk and low-order WFE, which enable stable starlight speckles on the science detector that can be removed by image subtraction. We describe the control strategy and the budget framework for estimating and budgeting the elements of wavefront stability, and the modeling strategy to evaluate it.

Memory-Based Decision-Making with Heuristics: Evidence for a Controlled Activation of Memory Representations

ERIC Educational Resources Information Center

Khader, Patrick H.; Pachur, Thorsten; Meier, Stefanie; Bien, Siegfried; Jost, Kerstin; Rosler, Frank

2011-01-01

Many of our daily decisions are memory based, that is, the attribute information about the decision alternatives has to be recalled. Behavioral studies suggest that for such decisions we often use simple strategies (heuristics) that rely on controlled and limited information search. It is assumed that these heuristics simplify decision-making by…

Economic evaluation of an area-wide integrated pest management program to control the Asian tiger mosquito in New Jersey

USDA-ARS?s Scientific Manuscript database

Aedes albopictus is the most invasive mosquito in the world, an important disease vector, and a biting nuisance that limits outdoor activities. Area-wide integrated pest management (AW-IPM) is the recommended control strategy. We conducted an economic evaluation of the AW-IPM project in Mercer and ...

Autonomous Optimization of Targeted Stimulation of Neuronal Networks

PubMed Central

Kumar, Sreedhar S.; Wülfing, Jan; Okujeni, Samora; Boedecker, Joschka; Riedmiller, Martin

2016-01-01

Driven by clinical needs and progress in neurotechnology, targeted interaction with neuronal networks is of increasing importance. Yet, the dynamics of interaction between intrinsic ongoing activity in neuronal networks and their response to stimulation is unknown. Nonetheless, electrical stimulation of the brain is increasingly explored as a therapeutic strategy and as a means to artificially inject information into neural circuits. Strategies using regular or event-triggered fixed stimuli discount the influence of ongoing neuronal activity on the stimulation outcome and are therefore not optimal to induce specific responses reliably. Yet, without suitable mechanistic models, it is hardly possible to optimize such interactions, in particular when desired response features are network-dependent and are initially unknown. In this proof-of-principle study, we present an experimental paradigm using reinforcement-learning (RL) to optimize stimulus settings autonomously and evaluate the learned control strategy using phenomenological models. We asked how to (1) capture the interaction of ongoing network activity, electrical stimulation and evoked responses in a quantifiable ‘state’ to formulate a well-posed control problem, (2) find the optimal state for stimulation, and (3) evaluate the quality of the solution found. Electrical stimulation of generic neuronal networks grown from rat cortical tissue in vitro evoked bursts of action potentials (responses). We show that the dynamic interplay of their magnitudes and the probability to be intercepted by spontaneous events defines a trade-off scenario with a network-specific unique optimal latency maximizing stimulus efficacy. An RL controller was set to find this optimum autonomously. Across networks, stimulation efficacy increased in 90% of the sessions after learning and learned latencies strongly agreed with those predicted from open-loop experiments. Our results show that autonomous techniques can exploit quantitative relationships underlying activity-response interaction in biological neuronal networks to choose optimal actions. Simple phenomenological models can be useful to validate the quality of the resulting controllers. PMID:27509295

Autonomous Optimization of Targeted Stimulation of Neuronal Networks.

PubMed

Kumar, Sreedhar S; Wülfing, Jan; Okujeni, Samora; Boedecker, Joschka; Riedmiller, Martin; Egert, Ulrich

2016-08-01

Driven by clinical needs and progress in neurotechnology, targeted interaction with neuronal networks is of increasing importance. Yet, the dynamics of interaction between intrinsic ongoing activity in neuronal networks and their response to stimulation is unknown. Nonetheless, electrical stimulation of the brain is increasingly explored as a therapeutic strategy and as a means to artificially inject information into neural circuits. Strategies using regular or event-triggered fixed stimuli discount the influence of ongoing neuronal activity on the stimulation outcome and are therefore not optimal to induce specific responses reliably. Yet, without suitable mechanistic models, it is hardly possible to optimize such interactions, in particular when desired response features are network-dependent and are initially unknown. In this proof-of-principle study, we present an experimental paradigm using reinforcement-learning (RL) to optimize stimulus settings autonomously and evaluate the learned control strategy using phenomenological models. We asked how to (1) capture the interaction of ongoing network activity, electrical stimulation and evoked responses in a quantifiable 'state' to formulate a well-posed control problem, (2) find the optimal state for stimulation, and (3) evaluate the quality of the solution found. Electrical stimulation of generic neuronal networks grown from rat cortical tissue in vitro evoked bursts of action potentials (responses). We show that the dynamic interplay of their magnitudes and the probability to be intercepted by spontaneous events defines a trade-off scenario with a network-specific unique optimal latency maximizing stimulus efficacy. An RL controller was set to find this optimum autonomously. Across networks, stimulation efficacy increased in 90% of the sessions after learning and learned latencies strongly agreed with those predicted from open-loop experiments. Our results show that autonomous techniques can exploit quantitative relationships underlying activity-response interaction in biological neuronal networks to choose optimal actions. Simple phenomenological models can be useful to validate the quality of the resulting controllers.

JPRS Report, Soviet Union, World Economy & International Relations, No. 7, July 1988

DTIC Science & Technology

1988-12-29

controlled by a group of voluntarily amalgamated people itself and is their creation and a democratic form of their free activity. The creativity of the...the most diverse financial groups , but which are united by a common development strategy and system of control (financial, primarily). We share the...transnational conglomerates controlled not by one but simultaneously by several financial group - soncerns and, in particular, transnational conglomerates

Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial.

PubMed

Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Ruiz-Marquez, Eloísa; Toril, Pilar; Reales, José M

2017-01-01

Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508) tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity , a commercial platform (http://www.lumosity.com/) or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group). Participants were tested individually before and after training to assess working memory (WM) and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1) the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task); (2) a marginal training effect was observed for the N -back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations.

Effects of Video Game Training on Measures of Selective Attention and Working Memory in Older Adults: Results from a Randomized Controlled Trial

PubMed Central

Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Ruiz-Marquez, Eloísa; Toril, Pilar; Reales, José M.

2017-01-01

Video game training with older adults potentially enhances aspects of cognition that decline with aging and could therefore offer a promising training approach. Although, previous published studies suggest that training can produce transfer, many of them have certain shortcomings. This randomized controlled trial (RCT; Clinicaltrials.gov ID: NCT02796508) tried to overcome some of these limitations by incorporating an active control group and the assessment of motivation and expectations. Seventy-five older volunteers were randomly assigned to the experimental group trained for 16 sessions with non-action video games from Lumosity, a commercial platform (http://www.lumosity.com/) or to an active control group trained for the same number of sessions with simulation strategy games. The final sample included 55 older adults (30 in the experimental group and 25 in the active control group). Participants were tested individually before and after training to assess working memory (WM) and selective attention and also reported their perceived improvement, motivation and engagement. The results showed improved performance across the training sessions. The main results were: (1) the experimental group did not show greater improvements in measures of selective attention and working memory than the active control group (the opposite occurred in the oddball task); (2) a marginal training effect was observed for the N-back task, but not for the Stroop task while both groups improved in the Corsi Blocks task. Based on these results, one can conclude that training with non-action games provide modest benefits for untrained tasks. The effect is not specific for that kind of training as a similar effect was observed for strategy video games. Groups did not differ in motivation, engagement or expectations. PMID:29163136

Remote modulation of neural activities via near-infrared triggered release of biomolecules.

PubMed

Li, Wei; Luo, Rongcong; Lin, Xudong; Jadhav, Amol D; Zhang, Zicong; Yan, Li; Chan, Chung-Yuan; Chen, Xianfeng; He, Jufang; Chen, Chia-Hung; Shi, Peng

2015-10-01

The capability to remotely control the release of biomolecules provides an unique opportunity to monitor and regulate neural signaling, which spans extraordinary spatial and temporal scales. While various strategies, including local perfusion, molecular "uncaging", or photosensitive polymeric materials, have been applied to achieve controlled releasing of neuro-active substances, it is still challenging to adopt these technologies in many experimental contexts that require a straightforward but versatile loading-releasing mechanism. Here, we develop a synthetic strategy for remotely controllable releasing of neuro-modulating molecules. This platform is based on microscale composite hydrogels that incorporate polypyrrole (PPy) nanoparticles as photo-thermal transducers and is triggered by near-infrared-light (NIR) irradiation. Specifically, we first demonstrate the utility of our technology by recapitulating the "turning assay" and "collapse assay", which involve localized treatment of chemotactic factors (e.g. Netrin or Semaphorin 3A) to subcellular neural elements and have been extensively used in studying axonal pathfinding. On a network scale, the photo-sensitive microgels are also validated for light-controlled releasing of neurotransmitters (e.g. glutamate). A single NIR-triggered release is sufficient to change the dynamics of a cultured hippocampal neuron network. Taking the advantage of NIR's capability to penetrate deep into live tissue, this technology is further shown to work similarly well in vivo, which is evidenced by synchronized spiking activity in response to NIR-triggered delivery of glutamate in rat auditory cortex, demonstrating remote control of brain activity without any genetic modifications. Notably, our nano-composite microgels are capable of delivering various molecules, ranging from small chemicals to large proteins, without involving any crosslinking chemistry. Such great versatility and ease-of-use will likely make our optically-controlled delivery technology a general and important tool in cell biology research. Copyright © 2015 Elsevier Ltd. All rights reserved.

Making Healthy Eating and Physical Activity Policy Practice: Process Evaluation of a Group Randomized Controlled Intervention in Afterschool Programs

ERIC Educational Resources Information Center

Weaver, R. Glenn; Beets, Michael W.; Hutto, Brent; Saunders, Ruth P.; Moore, Justin B.; Turner-McGrievy, Gabrielle; Huberty, Jennifer L.; Ward, Dianne S.; Pate, Russell R.; Beighle, Aaron; Freedman, Darcy

2015-01-01

This study describes the link between level of implementation and outcomes from an intervention to increase afterschool programs' (ASPs) achievement of healthy eating and physical activity (HE-PA) Standards. Ten intervention ASPs implemented the Strategies-To-Enhance-Practice (STEPs), a multi-component, adaptive intervention framework identifying…

A qualitative evaluation of a physician-delivered pedometer-based step count prescription strategy with insight from participants and treating physicians.

PubMed

Cooke, Alexandra B; Pace, Romina; Chan, Deborah; Rosenberg, Ellen; Dasgupta, Kaberi; Daskalopoulou, Stella S

2018-05-01

The integration of pedometers into clinical practice has the potential to enhance physical activity levels in patients with chronic disease. Our SMARTER randomized controlled trial demonstrated that a physician-delivered step count prescription strategy has measurable effects on daily steps, glycemic control, and insulin resistance in patients with type 2 diabetes and/or hypertension. In this study, we aimed to understand perceived barriers and facilitators influencing successful uptake and sustainability of the strategy, from patient and physician perspectives. Qualitative in-depth interviews were conducted in a purposive sample of physicians (n = 10) and participants (n = 20), including successful and less successful cases in terms of pedometer-assessed step count improvements. Themes that achieved saturation in either group through thematic analysis are presented. All participants appreciated the pedometer-based monitoring combined with step count prescriptions. Accountability to physicians and support offered by the trial coordinator influenced participant motivation. Those who increased step counts adopted strategies to integrate more steps into their routines and were able to overcome weather-related barriers by finding indoor alternative options to outdoor steps. Those who decreased step counts reported difficulty in overcoming weather-related challenges, health limitations and work constraints. Physicians indicated the strategy provided a framework for discussing physical activity and motivating patients, but emphasized the need for support from allied professionals to help deliver the strategy in busy clinical settings. A physician-delivered step count prescription strategy was feasibly integrated into clinical practice and successful in engaging most patients; however, continual support is needed for maximal engagement and sustained use. Copyright © 2018 Elsevier B.V. All rights reserved.

Childhood motor skill proficiency as a predictor of adolescent physical activity.

PubMed

Barnett, Lisa M; van Beurden, Eric; Morgan, Philip J; Brooks, Lyndon O; Beard, John R

2009-03-01

Cross-sectional evidence has demonstrated the importance of motor skill proficiency to physical activity participation, but it is unknown whether skill proficiency predicts subsequent physical activity. In 2000, children's proficiency in object control (kick, catch, throw) and locomotor (hop, side gallop, vertical jump) skills were assessed in a school intervention. In 2006/07, the physical activity of former participants was assessed using the Australian Physical Activity Recall Questionnaire. Linear regressions examined relationships between the reported time adolescents spent participating in moderate-to-vigorous or organized physical activity and their childhood skill proficiency, controlling for gender and school grade. A logistic regression examined the probability of participating in vigorous activity. Of 481 original participants located, 297 (62%) consented and 276 (57%) were surveyed. All were in secondary school with females comprising 52% (144). Adolescent time in moderate-to-vigorous and organized activity was positively associated with childhood object control proficiency. Respective models accounted for 12.7% (p = .001), and 18.2% of the variation (p = .003). Object control proficient children became adolescents with a 10% to 20% higher chance of vigorous activity participation. Object control proficient children were more likely to become active adolescents. Motor skill development should be a key strategy in childhood interventions aiming to promote long-term physical activity.

Design and methods for a pilot randomized clinical trial involving exercise and behavioral activation to treat comorbid type 2 diabetes and major depressive disorder

PubMed Central

Schneider, Kristin L.; Pagoto, Sherry L.; Handschin, Barbara; Panza, Emily; Bakke, Susan; Liu, Qin; Blendea, Mihaela; Ockene, Ira S.; Ma, Yunsheng

2011-01-01

Background The comorbidity of type 2 diabetes mellitus (T2DM) and depression is associated with poor glycemic control. Exercise has been shown to improve mood and glycemic control, but individuals with comorbid T2DM and depression are disproportionately sedentary compared to the general population and report more difficulty with exercise. Behavioral activation, an evidence-based depression psychotherapy, was designed to help people with depression make gradual behavior changes, and may be helpful to build exercise adherence in sedentary populations. This pilot randomized clinical trial will test the feasibility of a group exercise program enhanced with behavioral activation strategies among women with comorbid T2DM and depression. Methods/Design Sedentary women with inadequately controlled T2DM and depression (N=60) will be randomly assigned to one of two conditions: exercise or usual care. Participants randomized to the exercise condition will attend 38 behavioral activation-enhanced group exercise classes over 24 weeks in addition to usual care. Participants randomized to the usual care condition will receive depression treatment referrals and print information on diabetes management via diet and physical activity. Assessments will occur at baseline and 3-, 6-, and 9-months following randomization. The goals of this pilot study are to demonstrate feasibility and intervention acceptability, estimate the resources and costs required to deliver the intervention and to estimate the standard deviation of continuous outcomes (e.g., depressive symptoms and glycosylated hemoglobin) in preparation for a fully-powered randomized clinical trial. Discussion A novel intervention that combines exercise and behavioral activation strategies could potentially improve glycemic control and mood in women with comorbid type 2 diabetes and depression. Trial registration NCT01024790 PMID:21765864

A fault-tolerant control architecture for unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Drozeski, Graham R.

Research has presented several approaches to achieve varying degrees of fault-tolerance in unmanned aircraft. Approaches in reconfigurable flight control are generally divided into two categories: those which incorporate multiple non-adaptive controllers and switch between them based on the output of a fault detection and identification element, and those that employ a single adaptive controller capable of compensating for a variety of fault modes. Regardless of the approach for reconfigurable flight control, certain fault modes dictate system restructuring in order to prevent a catastrophic failure. System restructuring enables active control of actuation not employed by the nominal system to recover controllability of the aircraft. After system restructuring, continued operation requires the generation of flight paths that adhere to an altered flight envelope. The control architecture developed in this research employs a multi-tiered hierarchy to allow unmanned aircraft to generate and track safe flight paths despite the occurrence of potentially catastrophic faults. The hierarchical architecture increases the level of autonomy of the system by integrating five functionalities with the baseline system: fault detection and identification, active system restructuring, reconfigurable flight control; reconfigurable path planning, and mission adaptation. Fault detection and identification algorithms continually monitor aircraft performance and issue fault declarations. When the severity of a fault exceeds the capability of the baseline flight controller, active system restructuring expands the controllability of the aircraft using unconventional control strategies not exploited by the baseline controller. Each of the reconfigurable flight controllers and the baseline controller employ a proven adaptive neural network control strategy. A reconfigurable path planner employs an adaptive model of the vehicle to re-shape the desired flight path. Generation of the revised flight path is posed as a linear program constrained by the response of the degraded system. Finally, a mission adaptation component estimates limitations on the closed-loop performance of the aircraft and adjusts the aircraft mission accordingly. A combination of simulation and flight test results using two unmanned helicopters validates the utility of the hierarchical architecture.

Targeting activator protein 1 signaling pathway by bioactive natural agents: Possible therapeutic strategy for cancer prevention and intervention.

PubMed

Tewari, Devesh; Nabavi, Seyed Fazel; Nabavi, Seyed Mohammad; Sureda, Antoni; Farooqi, Ammad Ahmad; Atanasov, Atanas G; Vacca, Rosa Anna; Sethi, Gautam; Bishayee, Anupam

2018-02-01

Activator protein 1 (AP-1) is a key transcription factor in the control of several cellular processes responsible for cell survival proliferation and differentiation. Dysfunctional AP-1 expression and activity are involved in several severe diseases, especially inflammatory disorders and cancer. Therefore, targeting AP-1 has recently emerged as an attractive therapeutic strategy for cancer prevention and therapy. This review summarizes our current understanding of AP-1 biology and function as well as explores and discusses several natural bioactive compounds modulating AP-1-associated signaling pathways for cancer prevention and intervention. Current limitations, challenges, and future directions of research are also critically discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Active vibration control testing of the SPICES program: final demonstration article

NASA Astrophysics Data System (ADS)

Dunne, James P.; Jacobs, Jack H.

1996-05-01

The Synthesis and Processing of Intelligent Cost Effective Structures (SPICES) Program is a partnership program sponsored by the Advanced Research Projects Agency. The mission of the program is to develop cost effective material processing and synthesis technologies to enable new products employing active vibration suppression and control devices to be brought to market. The two year program came to fruition in 1995 through the fabrication of the final smart components and testing of an active plate combined with two trapezoidal rails, forming an active mount. Testing of the SPICES combined active mount took place at McDonnell Douglas facilities in St. Louis, MO, in October-December 1995. Approximately 15 dB reduction in overall response of a motor mounted on the active structure was achieved. Further details and results of the SPICES combined active mount demonstration testing are outlined. Results of numerous damping and control strategies that were developed and employed in the testing are presented, as well as aspects of the design and fabrication of the SPICES active mount components.

Taeniasis/cysticercosis trend worldwide and rationale for control.

PubMed

Montresor, Antonio; Palmer, Kevin

2006-01-01

Pig production has increased significantly worldwide in recent years. Small-scale pig husbandry has become a popular source of income in rural and resource-poor communities in most of developing countries. A parallel increase of human Taenia carrier and human cysticercosis is expected but detailed data are not available. However, Taenia solium is considered responsible for over 10% of acute case admission to the neurological ward of countries where it is endemic. The control strategy that seems at the moment more promising is a combination of the different tools available and includes the identification of areas at high risk and the presumptive treatment of the suspected cases and their families. This active finding and treatment of probable tapeworm carriers should be accompanied by health education and control swine cysticercosis. WHO invites all endemic countries to recognize the importance of taeniasis/cysticercosis control and to collect epidemiological data and to adopt policies and strategies for its control.

Taeniasis/cysticercosis trend worldwide and rationale for control

PubMed Central

Montresor, Antonio; Palmer, Kevin

2017-01-01

Pig production has increased significantly worldwide in the recent years. Small-scale pig husbandry has become a popular source of income in rural and resource-poor communities in most of developing countries. A parallel increase of human Taenia carrier and human cysticercosis is expected but detailed data are not available. However, Taenia solium is considered responsible of over 10% of acute case admission to the neurological ward of countries where it is endemic. The control strategy that seems at the moment more promising is a combination of the different tools available and includes the identification of areas at high risk and the presumptive treatment of the suspected cases and their families. This active finding and treatment of probable tapeworm carries should be accompanied by health education and control swine cysticercosis. WHO invite all endemic countries to recognize the importance of taeniasis/cysticercosis control and to collect epidemiological data and to adopt policies and strategies for its control. PMID:16337431

Simulation Comparison of Wake Mitigation Control Strategies for a Two-Turbine Case

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

Fleming, Paul; Gebraad, Pieter M. O.; Lee, Sang

2015-12-01

Wind turbines arranged in a wind plant impact each other through their wakes. Wind plant control is an active research field that attempts to improve wind plant performance by coordinating control of individual turbines to take into account these turbine–wake interactions. High-fidelity simulations of a two-turbine fully waked scenario are used to investigate several wake mitigation strategies, in this paper, including modification of yaw and tilt angles of an upstream turbine to induce wake skew, as well as repositioning of the downstream turbine. The simulation results are compared through change relative to a baseline operation in terms of overall powermore » capture and loading on the upstream and downstream turbine. Results demonstrated improved power production for all methods. Moreover, analysis of control options, including individual pitch control, shows potential to minimize the increase of, or even reduce, turbine loads.« less

Performance Guaranteed Inertia Emulation forDiesel-Wind System Feed Microgrid via ModelReference Control

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

Melin, Alexander M.; Zhang, Yichen; Djouadi, Seddik

In this paper, a model reference control based inertia emulation strategy is proposed. Desired inertia can be precisely emulated through this control strategy so that guaranteed performance is ensured. A typical frequency response model with parametrical inertia is set to be the reference model. A measurement at a specific location delivers the information of disturbance acting on the diesel-wind system to the referencemodel. The objective is for the speed of the diesel-wind system to track the reference model. Since active power variation is dominantly governed by mechanical dynamics and modes, only mechanical dynamics and states, i.e., a swing-engine-governor system plusmore » a reduced-order wind turbine generator, are involved in the feedback control design. The controller is implemented in a three-phase diesel-wind system feed microgrid. The results show exact synthetic inertia is emulated, leading to guaranteed performance and safety bounds.« less

Rate-Based Model Predictive Control of Turbofan Engine Clearance

NASA Technical Reports Server (NTRS)

DeCastro, Jonathan A.

2006-01-01

An innovative model predictive control strategy is developed for control of nonlinear aircraft propulsion systems and sub-systems. At the heart of the controller is a rate-based linear parameter-varying model that propagates the state derivatives across the prediction horizon, extending prediction fidelity to transient regimes where conventional models begin to lose validity. The new control law is applied to a demanding active clearance control application, where the objectives are to tightly regulate blade tip clearances and also anticipate and avoid detrimental blade-shroud rub occurrences by optimally maintaining a predefined minimum clearance. Simulation results verify that the rate-based controller is capable of satisfying the objectives during realistic flight scenarios where both a conventional Jacobian-based model predictive control law and an unconstrained linear-quadratic optimal controller are incapable of doing so. The controller is evaluated using a variety of different actuators, illustrating the efficacy and versatility of the control approach. It is concluded that the new strategy has promise for this and other nonlinear aerospace applications that place high importance on the attainment of control objectives during transient regimes.

Dissociating the effects of semantic grouping and rehearsal strategies on event-related brain potentials.

PubMed

Schleepen, T M J; Markus, C R; Jonkman, L M

2014-12-01

The application of elaborative encoding strategies during learning, such as grouping items on similar semantic categories, increases the likelihood of later recall. Previous studies have suggested that stimuli that encourage semantic grouping strategies had modulating effects on specific ERP components. However, these studies did not differentiate between ERP activation patterns evoked by elaborative working memory strategies like semantic grouping and more simple strategies like rote rehearsal. Identification of neurocognitive correlates underlying successful use of elaborative strategies is important to understand better why certain populations, like children or elderly people, have problems applying such strategies. To compare ERP activation during the application of elaborative versus more simple strategies subjects had to encode either four semantically related or unrelated pictures by respectively applying a semantic category grouping or a simple rehearsal strategy. Another goal was to investigate if maintenance of semantically grouped vs. ungrouped pictures modulated ERP-slow waves differently. At the behavioral level there was only a semantic grouping benefit in terms of faster responding on correct rejections (i.e. when the memory probe stimulus was not part of the memory set). At the neural level, during encoding semantic grouping only had a modest specific modulatory effect on a fronto-central Late Positive Component (LPC), emerging around 650 ms. Other ERP components (i.e. P200, N400 and a second Late Positive Component) that had been earlier related to semantic grouping encoding processes now showed stronger modulation by rehearsal than by semantic grouping. During maintenance semantic grouping had specific modulatory effects on left and right frontal slow wave activity. These results stress the importance of careful control of strategy use when investigating the neural correlates of elaborative encoding. Copyright © 2014 Elsevier B.V. All rights reserved.

Boosting airway T-regulatory cells by gastrointestinal stimulation as a strategy for asthma control.

PubMed

Strickland, D H; Judd, S; Thomas, J A; Larcombe, A N; Sly, P D; Holt, P G

2011-01-01

The hallmark of atopic asthma is transient airways hyperresponsiveness (AHR) preceded by aeroallergen-induced Th-cell activation. This is preceded by upregulation of CD86 on resident airway dendritic cells (DCs) that normally lack competence in T-cell triggering. Moreover, AHR duration is controlled via T-regulatory (Treg) cells, which can attenuate CD86 upregulation on DC. We show that airway mucosal Treg/DC interaction represents an accessible therapeutic target for asthma control. Notably, baseline airway Treg activity in sensitized rats can be boosted by microbe-derived stimulation of the gut, resulting in enhanced capacity to control CD86 expression on airway DC triggered by aeroallergen and accelerated resolution of AHR.

Lateral stepping for postural correction in Parkinson's disease.

PubMed

King, Laurie A; Horak, Fay B

2008-03-01

To characterize the lateral stepping strategies for postural correction in patients with Parkinson's disease (PD) and the effect of their anti-parkinson medication. Observational study. Outpatient neuroscience laboratory. Thirteen participants with idiopathic PD in their on (PD on) and off (PD off) levodopa state and 14 healthy elderly controls. Movable platform with lateral translations of 12 cm at 14.6 cm/s ramp velocity. The incidence and characteristics of 3 postural strategies were observed: lateral side-step, crossover step, or no step. Corrective stepping was characterized by latency to step after perturbation onset, step velocity, and step length and presence of an anticipatory postural adjustment (APA). Additionally, percentages of trials resulting in falls were identified for each group. Whereas elderly control participants never fell, PD participants fell in 24% and 35% of trials in the on and off medication states, respectively. Both PD and control participants most often used a lateral side-step strategy; 70% (control), 67% (PD off), and 73% (PD on) of all trials, respectively. PD participants fell most often when using a crossover strategy (75% of all crossover trials) or no-step strategy (100% of all no-step trials). In the off medication state, PD participants' lateral stepping strategies were initiated later than controls (370+/-37 ms vs 280+/-10 ms, P<.01), and steps were smaller (254+/-20 mm vs 357+/-17 mm, P<.01) and slower (0.99+/-0.08 m/s vs 1.20+/-0.07 m/s, P<.05). No differences were found between the PD off versus PD on state in the corrective stepping characteristics. Unlike control participants, PD participants often (56% of side-step strategy trials) failed to activate an APA before stepping, although their APAs, when present, were of similar latency and magnitude as for control participants. Levodopa on or off state did not significantly affect falls, APAs, or lateral step latency, velocity, or amplitude (P>.05). PD participants showed significantly more postural instability and falls than age-matched controls when stepping was required for postural correction in response to lateral disequilibrium. Although PD participants usually used a similar lateral stepping strategy as controls in response to lateral translations, lack of an anticipatory lateral weight shift, and bradykinetic characteristics of the stepping responses help explain the greater rate of falls in participants with PD. Differences were not found between the levodopa on and off states. The results suggest that rehabilitation aimed at improving lateral stability in PD should include facilitating APAs before a lateral side-stepping strategy with faster and larger steps to recover equilibrium.

Design and baseline characteristics of participants in the Enhancing Physical Activity and Reducing Obesity through Smartcare and Financial Incentives (EPAROSFI): A pilot randomized controlled trial.

PubMed

Shin, Dong Wook; Joh, Hee-Kyung; Yun, Jae Moon; Kwon, Hyuk Tae; Lee, Hyejin; Min, Hyeyeon; Shin, Jung-Hyun; Chung, Won Joo; Park, Jin Ho; Cho, BeLong

2016-03-01

An activity tracker combined with a smartphone application (smartcare) may help people track and receive feedback on their own activities. However, activity trackers themselves generally fail to drive long-term sustained engagement for a majority of users. One potential strategy for increasing the effectiveness of smartcare is through the use of incentives. The purpose of this pilot randomized trial is to test the feasibility of our intervention and to assess the extent to which smartcare with or without financial incentives can increase physical activity levels and reduce weight over a 12-week period. This study employs a three-arm, open-label randomized controlled trial design: control (standard basic education), smartcare, and smartcare plus financial incentives. Male university students with body mass index ≥ 27 are enrolled. Our primary and secondary endpoints are the amount of weight loss and the level of physical activity respectively. The weight loss goal is 3% of baseline at week 4, 5% at week 8, and 7% at week 12. The daily physical activity goal was individualized according to the participants' weight. Process incentives are accumulated when participants met daily physical activity goals, and outcome incentives are provided when they met weight reduction goals. Given the global increase in physical inactivity and obesity, there is a growing need for effective, scalable, and affordable health promotion strategies. Our proof-of-concept study will provide the evidence for the combination of rising health promotion technology of activity trackers and smartphone applications with the modern concept of behavioral economics using financial incentives. Copyright © 2015. Published by Elsevier Inc.

Strategies for Involvement in Wildlife Issues.

ERIC Educational Resources Information Center

Kennedy, Carolyn L.; Nye, Donna I.

1984-01-01

Highlights a workshop with children focusing on the treatment of controversial issues and guidelines typically provided by school districts or organizations. Activities designed to stimulate discussion on three issues (endangered species, acid rain, and predator control) are included. (BC)

Cholera Fact Sheet

MedlinePlus

... of more than 50 partners active in cholera control globally, including academic institutions, non-governmental organisations and United Nations agencies. Through the GTFCC and with support from donors, WHO works to: promote the design and implementation of global strategies to contribute to ...

Guided goal setting: effectiveness in a dietary and physical activity intervention with low-income adolescents.

PubMed

Shilts, Mical Kay; Horowitz, Marcel; Townsend, Marilyn S

2009-01-01

Determining the effectiveness of the guided goal setting strategy on changing adolescents' dietary and physical activity self-efficacy and behaviors. Adolescents were individually assigned to treatment (intervention with guided goal setting) or control conditions (intervention without guided goal setting) with data collected before and after the education intervention. Urban middle school in a low-income community in Central California. Ethnically diverse middle school students (n = 94, 55% male) who were participants of a USDA nutrition education program. Driven by the Social Cognitive Theory, the intervention targeted dietary and physical activity behaviors of adolescents. Dietary self-efficacy and behavior; physical activity self-efficacy and behavior; goal effort and spontaneous goal setting. ANCOVA and path analysis were performed using the full sample and a sub-sample informed by Locke's recommendations (accounting for goal effort and spontaneous goal setting). No significant differences were found between groups using the full sample. Using the sub-sample, greater gains in dietary behavior (p < .05), physical activity behavior (p < .05), and physical activity self-efficacy (p < .05) were made by treatment participants compared to control participants. Change in physical activity behaviors was mediated by self-efficacy. Accounting for goal effort and spontaneous goal setting, this study provides some evidence that the use of guided goal setting with adolescents may be a viable strategy to promote dietary and physical activity behavior change.

Balancing effluent quality, economic cost and greenhouse gas emissions during the evaluation of (plant-wide) control/operational strategies in WWTPs.

PubMed

Flores-Alsina, Xavier; Arnell, Magnus; Amerlinck, Youri; Corominas, Lluís; Gernaey, Krist V; Guo, Lisha; Lindblom, Erik; Nopens, Ingmar; Porro, Jose; Shaw, Andy; Snip, Laura; Vanrolleghem, Peter A; Jeppsson, Ulf

2014-01-01

The objective of this paper was to show the potential additional insight that result from adding greenhouse gas (GHG) emissions to plant performance evaluation criteria, such as effluent quality (EQI) and operational cost (OCI) indices, when evaluating (plant-wide) control/operational strategies in wastewater treatment plants (WWTPs). The proposed GHG evaluation is based on a set of comprehensive dynamic models that estimate the most significant potential on-site and off-site sources of CO₂, CH₄ and N₂O. The study calculates and discusses the changes in EQI, OCI and the emission of GHGs as a consequence of varying the following four process variables: (i) the set point of aeration control in the activated sludge section; (ii) the removal efficiency of total suspended solids (TSS) in the primary clarifier; (iii) the temperature in the anaerobic digester; and (iv) the control of the flow of anaerobic digester supernatants coming from sludge treatment. Based upon the assumptions built into the model structures, simulation results highlight the potential undesirable effects of increased GHG production when carrying out local energy optimization of the aeration system in the activated sludge section and energy recovery from the AD. Although off-site CO₂ emissions may decrease, the effect is counterbalanced by increased N₂O emissions, especially since N₂O has a 300-fold stronger greenhouse effect than CO₂. The reported results emphasize the importance and usefulness of using multiple evaluation criteria to compare and evaluate (plant-wide) control strategies in a WWTP for more informed operational decision making. © 2013.

Strategy of Infection Control in Immunosuppressive Therapy for ANCA-Associated Vasculitis

PubMed Central

2013-01-01

Antineutrophil cytoplasmic antibodies (ANCA) are well known to be associated with small vessel vasculitic diseases such as microscopic polyangiitis (MPA), allergic granulomatous angiitis (AGA), and Granulomatosis with poly angiitis: GPA (Wegener’s). Disease assessment by 1) vasculitic activity, 2) damage resulting from vasculitis, and 3) patient function, were the required endpoints for the therapeutic trials in ANCA-associated vasculitis (AAV). Harmonized steroids and cyclophosphamide or azathioprine are effective for active AAV. In evaluating tools for monitoring disease, titers of ANCA and the levels of CRP were found useful in AAV. However, it will be important for clinicians to observe AAV patients more closely and reduce immunosuppressive drug doses more cautiously, especially to prevent several infections (i.e., deep mycosis, pneumocystis jirovecii pneumonia and cytomegalovirus). We indicated that strategy of infection control in immunosuppressive therapy for AAV. (J Jpn Coll Angiol, 2009, 49: 93-99) PMID:23641277

A Designed Peptide Targets Two Types of Modifications of p53 with Anti-cancer Activity.

PubMed

Liang, Lunxi; Wang, Huanbin; Shi, Hubing; Li, Zhaoli; Yao, Han; Bu, Zhigao; Song, Ningning; Li, Chushu; Xiang, Dabin; Zhang, Yao; Wang, Jilin; Hu, Ye; Xu, Qi; Ma, Yanlei; Cheng, Zhongyi; Wang, Yingchao; Zhao, Shuliang; Qian, Jin; Chen, Yingxuan; Fang, Jing-Yuan; Xu, Jie

2018-06-21

Many cancer-related proteins are controlled by composite post-translational modifications (PTMs), but prevalent strategies only target one type of modification. Here we describe a designed peptide that controls two types of modifications of the p53 tumor suppressor, based on the discovery of a protein complex that suppresses p53 (suppresome). We found that Morn3, a cancer-testis antigen, recruits different PTM enzymes, such as sirtuin deacetylase and ubiquitin ligase, to confer composite modifications on p53. The molecular functions of Morn3 were validated through in vivo assays and chemico-biological intervention. A rationally designed Morn3-targeting peptide (Morncide) successfully activated p53 and suppressed tumor growth. These findings shed light on the regulation of protein PTMs and present a strategy for targeting two modifications with one molecule. Copyright © 2018 Elsevier Ltd. All rights reserved.

Chassis integrated control for active suspension, active front steering and direct yaw moment systems using hierarchical strategy

NASA Astrophysics Data System (ADS)

Zhao, Jing; Wong, Pak Kin; Ma, Xinbo; Xie, Zhengchao

2017-01-01

This paper proposes a novel integrated controller with three-layer hierarchical structure to coordinate the interactions among active suspension system (ASS), active front steering (AFS) and direct yaw moment control (DYC). First of all, a 14-degree-of-freedom nonlinear vehicle dynamic model is constructed. Then, an upper layer is designed to calculate the total corrected moment for ASS and intermediate layer based on linear moment distribution. By considering the working regions of the AFS and DYC, the intermediate layer is functionalised to determine the trigger signal for the lower layer with corresponding weights. The lower layer is utilised to separately trace the desired value of each local controller and achieve the local control objectives of each subsystem. Simulation results show that the proposed three-layer hierarchical structure is effective in handling the working region of the AFS and DYC, while the quasi-experimental result shows that the proposed integrated controller is able to improve the lateral and vertical dynamics of the vehicle effectively as compared with a conventional electronic stability controller.

A Biomimetic Propulsor for Active Noise Control. Part 2: Theory

NASA Astrophysics Data System (ADS)

Annaswamy Krol, A., Jr.; Bandyopadhyay, P. R.

2000-11-01

The alteration of radiated noise in underwater propulsors using biomimetic active control is considered. Wake momentum filling is carried out by introducing artificial muscles at the trailing edge of a stator blade of an upstream stator propulsor, and articulating them like a fish tail (see companion abstract Part 1). Using a systems framework, we derive a methodology for the articulation of the muscles with active control. The unsteady force produced on the rotor because of velocity perturbations due to actuator displacements, wake deficits caused by stator boundary layers, and blade rotation is modeled. Linear and adaptive nonlinear control strategies are described for articulating the tail using unsteady force measurements. This active control procedure can be viewed as the realization of “virtual” blades with different sweep and noise characteristics and can affect the noise spectrum due to direct radiation significantly. The work provides an understanding of the effect of nonuniform wakes on radiated noise and can lead to a general approach by which wakes can be altered.

Decentralized stabilization of semi-active vibrating structures

NASA Astrophysics Data System (ADS)

Pisarski, Dominik

2018-02-01

A novel method of decentralized structural vibration control is presented. The control is assumed to be realized by a semi-active device. The objective is to stabilize a vibrating system with the optimal rates of decrease of the energy. The controller relies on an easily implemented decentralized switched state-feedback control law. It uses a set of communication channels to exchange the state information between the neighboring subcontrollers. The performance of the designed method is validated by means of numerical experiments performed for a double cantilever system equipped with a set of elastomers with controlled viscoelastic properties. In terms of the assumed objectives, the proposed control strategy significantly outperforms the passive damping cases and is competitive with a standard centralized control. The presented methodology can be applied to a class of bilinear control systems concerned with smart structural elements.

Efficacy and safety of strategies to preserve stable extracorporeal life support flow during simulated hypovolemia.

PubMed

Simons, A P; Lindelauf, A A M A; Ganushchak, Y M; Maessen, J G; Weerwind, P W

2014-01-01

Without volume-buffering capacity in extracorporeal life support (ELS) systems, hypovolemia can acutely reduce support flow. This study aims at evaluating efficacy and safety of strategies for preserving stable ELS during hypovolemia. Flow and/or pressure-guided servo pump control, a reserve-driven control strategy and a volume buffer capacity (VBC) device were evaluated with respect to pump flow, venous line pressure and arterial gaseous microemboli (GME) during simulated normovolemia and hypovolemia. Normovolemia resulted in a GME-free pump flow of 3.1 ± 0.0 L/min and a venous line pressure of -10 ± 1 mmHg. Hypovolemia without servo pump control resulted in a GME-loaded flow of 2.3 ± 0.4 L/min with a venous line pressure of -114 ± 52 mmHg. Servo control resulted in an unstable and GME-loaded flow of 1.5 ± 1.2 L/min. With and without servo pump control, the VBC device stabilised flow (SD = 0.2 and 0.0 L/min, respectively) and venous line pressure (SD=51 and 4 mmHg, respectively) with near-absent GME activity. Reserve-driven pump control combined with a VBC device restored a near GME-free flow of 2.7 ± 0.0 L/min with a venous line pressure of -9 ± 0 mmHg. In contrast to a reserve-driven pump control strategy combined with a VBC device, flow and pressure servo control for ELS show evident deficits in preserving stable and safe ELS flow during hypovolemia.

Discovering successful strategies for diabetic self-management: a qualitative comparative study

PubMed Central

Baer, Roberta; Nash, Anita; Perez, Noe

2017-01-01

Objective This project explored lifestyles of patients in good and poor control to identify naturally occurring practices and strategies that result in successful diabetes management. Research design and methods Semistructured interviews with adult patients with type 2 diabetes explored diet, food preparation, physical activity, medication use and glucose monitoring. Patients (n=56) were classified into good (A1C <7.0%), fair (7.0%8.0%) control groups and matched across groups on diabetes duration (±5 years) and medication modality (none, oral, insulin±oral) to control for non-lifestyle factors. A qualitative comparative analysis identified practices that distinguished glycemic groups. Results Good control patients were more likely to test their glucose two or more times a day and reduce their sodium intake, as well as increase fruits and vegetables and limit portion sizes, some attaining good control without exercise. Fair control patients discussed several dietary strategies including limiting sweets, drinking non-caloric beverages, reducing carbs, ‘cheating’ (eating only a few sweets/limiting carbs in one meal to have more in another meal) and tested their glucose once a day. Poor control patients were more likely to skip antidiabetic medications and not test their glucose. Conclusions Although clinical trials indicate most self-management practices have limited effectiveness over time, increased glucose monitoring is a valuable component in daily management. Research is needed on effectiveness of dietary strategies that emphasize sodium monitoring and allow some degree of cheating. Reoffering diabetes education classes and providing pill boxes as memory aids may help improve poor control. PMID:28761649

Discovering successful strategies for diabetic self-management: a qualitative comparative study.

PubMed

Weller, Susan C; Baer, Roberta; Nash, Anita; Perez, Noe

2017-01-01

This project explored lifestyles of patients in good and poor control to identify naturally occurring practices and strategies that result in successful diabetes management. Semistructured interviews with adult patients with type 2 diabetes explored diet, food preparation, physical activity, medication use and glucose monitoring. Patients (n=56) were classified into good (A1C <7.0%), fair (7.0%8.0%) control groups and matched across groups on diabetes duration (±5 years) and medication modality (none, oral, insulin±oral) to control for non-lifestyle factors. A qualitative comparative analysis identified practices that distinguished glycemic groups. Good control patients were more likely to test their glucose two or more times a day and reduce their sodium intake, as well as increase fruits and vegetables and limit portion sizes, some attaining good control without exercise. Fair control patients discussed several dietary strategies including limiting sweets, drinking non-caloric beverages, reducing carbs, 'cheating' (eating only a few sweets/limiting carbs in one meal to have more in another meal) and tested their glucose once a day. Poor control patients were more likely to skip antidiabetic medications and not test their glucose. Although clinical trials indicate most self-management practices have limited effectiveness over time, increased glucose monitoring is a valuable component in daily management. Research is needed on effectiveness of dietary strategies that emphasize sodium monitoring and allow some degree of cheating. Reoffering diabetes education classes and providing pill boxes as memory aids may help improve poor control.

How are things adding up? Neural differences between arithmetic operations are due to general problem solving strategies.

PubMed

Tschentscher, Nadja; Hauk, Olaf

2014-05-15

A number of previous studies have interpreted differences in brain activation between arithmetic operation types (e.g. addition and multiplication) as evidence in favor of distinct cortical representations, processes or neural systems. It is still not clear how differences in general task complexity contribute to these neural differences. Here, we used a mental arithmetic paradigm to disentangle brain areas related to general problem solving from those involved in operation type specific processes (addition versus multiplication). We orthogonally varied operation type and complexity. Importantly, complexity was defined not only based on surface criteria (for example number size), but also on the basis of individual participants' strategy ratings, which were validated in a detailed behavioral analysis. We replicated previously reported operation type effects in our analyses based on surface criteria. However, these effects vanished when controlling for individual strategies. Instead, procedural strategies contrasted with memory retrieval reliably activated fronto-parietal and motor regions, while retrieval strategies activated parietal cortices. This challenges views that operation types rely on partially different neural systems, and suggests that previously reported differences between operation types may have emerged due to invalid measures of complexity. We conclude that mental arithmetic is a powerful paradigm to study brain networks of abstract problem solving, as long as individual participants' strategies are taken into account. Copyright © 2014 Elsevier Inc. All rights reserved.

Investing in youth tobacco control: a review of smoking prevention and control strategies

PubMed Central

Lantz, P.; Jacobson, P.; Warner, K.; Wasserman, J.; Pollack, H.; Berson, J.; Ahlstrom, A.

2000-01-01

OBJECTIVE—To provide a comprehensive review of interventions and policies aimed at reducing youth cigarette smoking in the United States, including strategies that have undergone evaluation and emerging innovations that have not yet been assessed for efficacy.
DATA SOURCES—Medline literature searches, books, reports, electronic list servers, and interviews with tobacco control advocates.
DATA SYNTHESIS—Interventions and policy approaches that have been assessed or evaluated were categorised using a typology with seven categories (school based, community interventions, mass media/public education, advertising restrictions, youth access restrictions, tobacco excise taxes, and direct restrictions on smoking). Novel and largely untested interventions were described using nine categories.
CONCLUSIONS—Youth smoking prevention and control efforts have had mixed results. However, this review suggests a number of prevention strategies that are promising, especially if conducted in a coordinated way to take advantage of potential synergies across interventions. Several types of strategies warrant additional attention and evaluation, including aggressive media campaigns, teen smoking cessation programmes, social environment changes, community interventions, and increasing cigarette prices. A significant proportion of the resources obtained from the recent settlement between 46 US states and the tobacco industry should be devoted to expanding, improving and evaluating "youth centred" tobacco prevention and control activities.


Keywords: youth smoking prevention; teen cessation programmes; community interventions; policy PMID:10691758

Target prioritization and strategy selection for active case-finding of pulmonary tuberculosis: a tool to support country-level project planning.

PubMed

Nishikiori, Nobuyuki; Van Weezenbeek, Catharina

2013-02-02

Despite the progress made in the past decade, tuberculosis (TB) control still faces significant challenges. In many countries with declining TB incidence, the disease tends to concentrate in vulnerable populations that often have limited access to health care. In light of the limitations of the current case-finding approach and the global urgency to improve case detection, active case-finding (ACF) has been suggested as an important complementary strategy to accelerate tuberculosis control especially among high-risk populations. The present exercise aims to develop a model that can be used for county-level project planning. A simple deterministic model was developed to calculate the number of estimated TB cases diagnosed and the associated costs of diagnosis. The model was designed to compare cost-effectiveness parameters, such as the cost per case detected, for different diagnostic algorithms when they are applied to different risk populations. The model was transformed into a web-based tool that can support national TB programmes and civil society partners in designing ACF activities. According to the model output, tuberculosis active case-finding can be a costly endeavor, depending on the target population and the diagnostic strategy. The analysis suggests the following: (1) Active case-finding activities are cost-effective only if the tuberculosis prevalence among the target population is high. (2) Extensive diagnostic methods (e.g. X-ray screening for the entire group, use of sputum culture or molecular diagnostics) can be applied only to very high-risk groups such as TB contacts, prisoners or people living with human immunodeficiency virus (HIV) infection. (3) Basic diagnostic approaches such as TB symptom screening are always applicable although the diagnostic yield is very limited. The cost-effectiveness parameter was sensitive to local diagnostic costs and the tuberculosis prevalence of target populations. The prioritization of appropriate target populations and careful selection of cost-effective diagnostic strategies are critical prerequisites for rational active case-finding activities. A decision to conduct such activities should be based on the setting-specific cost-effectiveness analysis and programmatic assessment. A web-based tool was developed and is available to support national tuberculosis programmes and partners in the formulation of cost-effective active case-finding activities at the national and subnational levels.

Towards effective prevention and control of helminth neglected tropical diseases in the Western Pacific Region through multi-disease and multi-sectoral interventions.

PubMed

Nakagawa, Jun; Ehrenberg, John P; Nealon, Joshua; Fürst, Thomas; Aratchige, Padmasiri; Gonzales, Glenda; Chanthavisouk, Chitsavang; Hernandez, Leda M; Fengthong, Tayphasavanh; Utzinger, Jürg; Steinmann, Peter

2015-01-01

Neglected tropical diseases (NTDs) cause serious health, social and economic burdens in the countries of the World Health Organization Western Pacific Region. Among the NTDs, helminth infections are particularly prominent with regard to the number of infected individuals and health impact. Co-endemicity is common among impoverished and marginalized populations. To achieve effective and sustainable control of helminth NTDs, a deeper understanding of the social-ecological systems governing their endemicity and strategies beyond preventive chemotherapy are required to tackle the multiple causes of infection and re-infection. We discuss the feasibility of implementing multi-disease, multi-sectoral intervention packages for helminth NTDs in the Western Pacific Region. After reviewing the main determinants for helminth NTD endemicity and current control strategies, key control activities that involve or concern other programmes within and beyond the health sector are discussed. A considerable number of activities that have an impact on more than one helminth NTD are identified in a variety of sectors, suggesting an untapped potential for synergies. We also highlight the challenges of multi-sectoral collaboration, particularly of involving non-health sectors. We conclude that multi-sectoral collaboration for helminth NTD control is feasible if the target diseases and sectors are carefully selected. To do so, an incentive analysis covering key stakeholders in the sectors is crucial, and the disease-control strategies need to be well understood. The benefits of multi-disease, multi-sectoral approaches could go beyond immediate health impacts by contributing to sustainable development, raising educational attainment, increasing productivity and reducing health inequities. Copyright © 2013 Elsevier B.V. All rights reserved.

ESMPE: A combined strategy for school tuberculosis prevention and control proposed by Dalian, China.

PubMed

Wang, Xichen; Jiang, Hongbo; Wang, Xuemei; Liu, Hongyu; Zhou, Ling; Lu, Xiwei

2017-01-01

Although China has paid more attention on the prevention and control of tuberculosis (TB) in schools, several unsolved questions in this field still threaten the progress of TB control. Therefore, there is an urgent need to develop a systematic and practical strategy for Chinese school TB prevention and control system. In this study, we aimed to assess the feasibility of a combined strategy named ESMPE (examination, screening, monitoring, prevention and education) that adhere to the basic principles of Chinese schools TB control strategy. The ESMPE strategy included five sections, namely TB screening during physical examination for the school freshmen entrances, screening of close contacts, monitoring of high-risk schools, preventive treatment and TB education. The effectiveness of ESMPE strategy was evaluated from 2011 to 2016. The original data were provided by the Dalian Tuberculosis Hospital. Descriptive analysis and nonparametric tests were used for comparing statistical differences of results between different years. The detection rate of active pulmonary TB in school freshmen was decreased from 2011 to 2016 (χ2 = 41.941, P = 6.0551E-8). 97.22% (17,043/17,530) of close contacts experienced close contacts screening, and the secondary attack rate (SAR) of TB in schools fell by 146.35/105 from 2011 to 2012, and finally reduced to 85.57/105 in 2016. There was a significant correlation between SAR of student TB and the rate of screened close contacts (r = -0.924, P = 0.009). TB incidence of five monitored schools had a substantial decline after receiving monitoring, and this declining trend continued in 2016. Due to the TB education and advanced screening methods, the mean of diagnostic delay time in students with TB was shortened (15.71 days), while still fewer latent TB infection students received preventive treatment (30.38%). The ESMPE strategy has shown a favorable effect on TB prevention and control in Dalian schools. More systematic evidence is needed on the effect of this strategy in reducing the incidence of TB in schools from other settings prior to its further scaling-up in China.

Comparison of individual pitch and smart rotor control strategies for load reduction

NASA Astrophysics Data System (ADS)

Plumley, C.; Leithead, W.; Jamieson, P.; Bossanyi, E.; Graham, M.

2014-06-01

Load reduction is increasingly seen as an essential part of controller and wind turbine design. On large multi-MW wind turbines that experience high levels of wind shear and turbulence across the rotor, individual pitch control and smart rotor control are being considered. While individual pitch control involves adjusting the pitch of each blade individually to reduce the cyclic loadings on the rotor, smart rotor control involves activating control devices distributed along the blades to alter the local aerodynamics of the blades. Here we investigate the effectiveness of using a DQ-axis control and a distributed (independent) control for both individual pitch and trailing edge flap smart rotor control. While load reductions are similar amongst the four strategies across a wide range of variables, including blade root bending moments, yaw bearing and shaft, the pitch actuator requirements vary. The smart rotor pitch actuator has reduced travel, rates, accelerations and power requirements than that of the individual pitch controlled wind turbines. This benefit alone however would be hard to justify the added design complexities of using a smart rotor, which can be seen as an alternative to upgrading the pitch actuator and bearing. In addition, it is found that the independent control strategy is apt at roles that the collective pitch usually targets, such as tower motion and speed control, and it is perhaps here, in supplementing other systems, that the future of the smart rotor lies.

Demonstration of Active Combustion Control

NASA Technical Reports Server (NTRS)

Lovett, Jeffrey A.; Teerlinck, Karen A.; Cohen, Jeffrey M.

2008-01-01

The primary objective of this effort was to demonstrate active control of combustion instabilities in a direct-injection gas turbine combustor that accurately simulates engine operating conditions and reproduces an engine-type instability. This report documents the second phase of a two-phase effort. The first phase involved the analysis of an instability observed in a developmental aeroengine and the design of a single-nozzle test rig to replicate that phenomenon. This was successfully completed in 2001 and is documented in the Phase I report. This second phase was directed toward demonstration of active control strategies to mitigate this instability and thereby demonstrate the viability of active control for aircraft engine combustors. This involved development of high-speed actuator technology, testing and analysis of how the actuation system was integrated with the combustion system, control algorithm development, and demonstration testing in the single-nozzle test rig. A 30 percent reduction in the amplitude of the high-frequency (570 Hz) instability was achieved using actuation systems and control algorithms developed within this effort. Even larger reductions were shown with a low-frequency (270 Hz) instability. This represents a unique achievement in the development and practical demonstration of active combustion control systems for gas turbine applications.

Neural differences in the processing of semantic relationships across cultures.

PubMed

Gutchess, Angela H; Hedden, Trey; Ketay, Sarah; Aron, Arthur; Gabrieli, John D E

2010-06-01

The current study employed functional MRI to investigate the contribution of domain-general (e.g. executive functions) and domain-specific (e.g. semantic knowledge) processes to differences in semantic judgments across cultures. Previous behavioral experiments have identified cross-cultural differences in categorization, with East Asians preferring strategies involving thematic or functional relationships (e.g. cow-grass) and Americans preferring categorical relationships (e.g. cow-chicken). East Asians and American participants underwent functional imaging while alternating between categorical or thematic strategies to sort triads of words, as well as matching words on control trials. Many similarities were observed. However, across both category and relationship trials compared to match (control) trials, East Asians activated a frontal-parietal network implicated in controlled executive processes, whereas Americans engaged regions of the temporal lobes and the cingulate, possibly in response to conflict in the semantic content of information. The results suggest that cultures differ in the strategies employed to resolve conflict between competing semantic judgments.

Regulation of two motor patterns enables the gradual adjustment of locomotion strategy in Caenorhabditis elegans

PubMed Central

Hums, Ingrid; Riedl, Julia; Mende, Fanny; Kato, Saul; Kaplan, Harris S; Latham, Richard; Sonntag, Michael; Traunmüller, Lisa; Zimmer, Manuel

2016-01-01

In animal locomotion a tradeoff exists between stereotypy and flexibility: fast long-distance travelling (LDT) requires coherent regular motions, while local sampling and area-restricted search (ARS) rely on flexible movements. We report here on a posture control system in C. elegans that coordinates these needs. Using quantitative posture analysis we explain worm locomotion as a composite of two modes: regular undulations versus flexible turning. Graded reciprocal regulation of both modes allows animals to flexibly adapt their locomotion strategy under sensory stimulation along a spectrum ranging from LDT to ARS. Using genetics and functional imaging of neural activity we characterize the counteracting interneurons AVK and DVA that utilize FLP-1 and NLP-12 neuropeptides to control both motor modes. Gradual regulation of behaviors via this system is required for spatial navigation during chemotaxis. This work shows how a nervous system controls simple elementary features of posture to generate complex movements for goal-directed locomotion strategies. DOI: http://dx.doi.org/10.7554/eLife.14116.001 PMID:27222228

Engineering live cell surfaces with functional polymers via cytocompatible controlled radical polymerization

NASA Astrophysics Data System (ADS)

Niu, Jia; Lunn, David J.; Pusuluri, Anusha; Yoo, Justin I.; O'Malley, Michelle A.; Mitragotri, Samir; Soh, H. Tom; Hawker, Craig J.

2017-06-01

The capability to graft synthetic polymers onto the surfaces of live cells offers the potential to manipulate and control their phenotype and underlying cellular processes. Conventional grafting-to strategies for conjugating preformed polymers to cell surfaces are limited by low polymer grafting efficiency. Here we report an alternative grafting-from strategy for directly engineering the surfaces of live yeast and mammalian cells through cell surface-initiated controlled radical polymerization. By developing cytocompatible PET-RAFT (photoinduced electron transfer-reversible addition-fragmentation chain-transfer polymerization), synthetic polymers with narrow polydispersity (Mw/Mn < 1.3) could be obtained at room temperature in 5 minutes. This polymerization strategy enables chain growth to be initiated directly from chain-transfer agents anchored on the surface of live cells using either covalent attachment or non-covalent insertion, while maintaining high cell viability. Compared with conventional grafting-to approaches, these methods significantly improve the efficiency of grafting polymer chains and enable the active manipulation of cellular phenotypes.

Study on DFIG wind turbines control strategy for improving frequency response characteristics

NASA Astrophysics Data System (ADS)

Zhao, Dongmei; Wu, Di; Liu, Yanhua; Zhou, Zhiyu

2012-01-01

The active and reactive power decoupling control for the double-fed induction generator wind turbines(DFIG) does not play a positive role to the frequency response ability of power grid because it performs as the hidden inertia for the power grid. If we want to improve the transient frequency stability of the wind turbine when it is integrated with the system, we must ameliorate its frequency response characteristics. The inability of frequency control due to DFIG decoupling control could be overcome through releasing (or absorbing) a part of the kinetic energy stored in the rotor, so as to increase (or decrease) active power injected to the power system when the deviation of power system frequency appears. This paper discusses the mathematical model of the variable speed DFIG, including the aerodynamic model, pitch control system model, shaft model, generator model and inverter control model, and other key components, focusing on the mathematical model of the converters in rotor side and grid side. Based on the existing model of wind generator, the paper attaches the frequency control model on the platform of the simulation software DIgSILENT/PowerFactory. The simulation results show that the proposed control strategy can response quickly to transient frequency deviation and prove that wind farms can participate in the system frequency regulation to a certain extent. Finally, the result verifies the accuracy and plausibility of the inverter control model which attaches the frequency control module.

Study on DFIG wind turbines control strategy for improving frequency response characteristics

NASA Astrophysics Data System (ADS)

Zhao, Dongmei; Wu, Di; Liu, Yanhua; Zhou, Zhiyu

2011-12-01

The active and reactive power decoupling control for the double-fed induction generator wind turbines(DFIG) does not play a positive role to the frequency response ability of power grid because it performs as the hidden inertia for the power grid. If we want to improve the transient frequency stability of the wind turbine when it is integrated with the system, we must ameliorate its frequency response characteristics. The inability of frequency control due to DFIG decoupling control could be overcome through releasing (or absorbing) a part of the kinetic energy stored in the rotor, so as to increase (or decrease) active power injected to the power system when the deviation of power system frequency appears. This paper discusses the mathematical model of the variable speed DFIG, including the aerodynamic model, pitch control system model, shaft model, generator model and inverter control model, and other key components, focusing on the mathematical model of the converters in rotor side and grid side. Based on the existing model of wind generator, the paper attaches the frequency control model on the platform of the simulation software DIgSILENT/PowerFactory. The simulation results show that the proposed control strategy can response quickly to transient frequency deviation and prove that wind farms can participate in the system frequency regulation to a certain extent. Finally, the result verifies the accuracy and plausibility of the inverter control model which attaches the frequency control module.

Infection Prevention Strategy in Hospitals in the Era of Community-Associated Methicillin-Resistant Staphylococcus aureus in the Asia-Pacific Region: A Review.

PubMed

Cho, Sun Young; Chung, Doo Ryeon

2017-05-15

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged as an important cause of healthcare-associated infection. CA-MRSA clones have replaced classic hospital MRSA clones in many countries and have shown higher potential in transmission and virulence than hospital MRSA clones. In particular, the emergence of CA-MRSA in the Asia-Pacific region is concerning owing to insufficient infection control measures in the region. The old strategies for infection prevention and control of MRSA comprised adherence to standard precaution and policy of active screening of MRSA carriers and decolonization, and it has been controversial which strategy is better in terms of outcome and cost-effectiveness. Epidemiological changes in MRSA has made the development of infection prevention strategy more complicated. Based on the literature review and the questionnaire survey, we considered infection prevention strategies for healthcare settings in the Asia-Pacific region in the era of CA-MRSA. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Application of eco-friendly tools and eco-bio-social strategies to control dengue vectors in urban and peri-urban settings in Thailand

PubMed Central

Kittayapong, Pattamaporn; Thongyuan, Suporn; Olanratmanee, Phanthip; Aumchareoun, Worawit; Koyadun, Surachart; Kittayapong, Rungrith; Butraporn, Piyarat

2012-01-01

Background Dengue is considered one of the most important vector-borne diseases in Thailand. Its incidence is increasing despite routine implementation of national dengue control programmes. This study, conducted during 2010, aimed to demonstrate an application of integrated, community-based, eco-bio-social strategies in combination with locally-produced eco-friendly vector control tools in the dengue control programme, emphasizing urban and peri-urban settings in eastern Thailand. Methodology Three different community settings were selected and were randomly assigned to intervention and control clusters. Key community leaders and relevant governmental authorities were approached to participate in this intervention programme. Ecohealth volunteers were identified and trained in each study community. They were selected among active community health volunteers and were trained by public health experts to conduct vector control activities in their own communities using environmental management in combination with eco-friendly vector control tools. These trained ecohealth volunteers carried out outreach health education and vector control during household visits. Management of public spaces and public properties, especially solid waste management, was efficiently carried out by local municipalities. Significant reduction in the pupae per person index in the intervention clusters when compared to the control ones was used as a proxy to determine the impact of this programme. Results Our community-based dengue vector control programme demonstrated a significant reduction in the pupae per person index during entomological surveys which were conducted at two-month intervals from May 2010 for the total of six months in the intervention and control clusters. The programme also raised awareness in applying eco-friendly vector control approaches and increased intersectoral and household participation in dengue control activities. Conclusion An eco-friendly dengue vector control programme was successfully implemented in urban and peri-urban settings in Thailand, through intersectoral collaboration and practical action at household level, with a significant reduction in vector densities. PMID:23318236

Application of eco-friendly tools and eco-bio-social strategies to control dengue vectors in urban and peri-urban settings in Thailand.

PubMed

Kittayapong, Pattamaporn; Thongyuan, Suporn; Olanratmanee, Phanthip; Aumchareoun, Worawit; Koyadun, Surachart; Kittayapong, Rungrith; Butraporn, Piyarat

2012-12-01

Dengue is considered one of the most important vector-borne diseases in Thailand. Its incidence is increasing despite routine implementation of national dengue control programmes. This study, conducted during 2010, aimed to demonstrate an application of integrated, community-based, eco-bio-social strategies in combination with locally-produced eco-friendly vector control tools in the dengue control programme, emphasizing urban and peri-urban settings in eastern Thailand. Three different community settings were selected and were randomly assigned to intervention and control clusters. Key community leaders and relevant governmental authorities were approached to participate in this intervention programme. Ecohealth volunteers were identified and trained in each study community. They were selected among active community health volunteers and were trained by public health experts to conduct vector control activities in their own communities using environmental management in combination with eco-friendly vector control tools. These trained ecohealth volunteers carried out outreach health education and vector control during household visits. Management of public spaces and public properties, especially solid waste management, was efficiently carried out by local municipalities. Significant reduction in the pupae per person index in the intervention clusters when compared to the control ones was used as a proxy to determine the impact of this programme. Our community-based dengue vector control programme demonstrated a significant reduction in the pupae per person index during entomological surveys which were conducted at two-month intervals from May 2010 for the total of six months in the intervention and control clusters. The programme also raised awareness in applying eco-friendly vector control approaches and increased intersectoral and household participation in dengue control activities. An eco-friendly dengue vector control programme was successfully implemented in urban and peri-urban settings in Thailand, through intersectoral collaboration and practical action at household level, with a significant reduction in vector densities.

Minnowbrook VI: 2009 Workshop on Flow Physics and Control for Internal and External Aerodynamics

NASA Technical Reports Server (NTRS)

LaGraff, John E.; Povinelli, Louis A.; Gostelow, J. Paul; Glauser, Mark

2010-01-01

Topics covered include: Flow Physics and control for Internal and External Aerodynamics (not in TOC...starts on pg13); Breaking CFD Bottlenecks in Gas-Turbine Flow-Path Design; Streamwise Vortices on the Convex Surfaces of Circular Cylinders and Turbomachinery Blading; DNS and Embedded DNS as Tools for Investigating Unsteady Heat Transfer Phenomena in Turbines; Cavitation, Flow Structure and Turbulence in the Tip Region of a Rotor Blade; Development and Application of Plasma Actuators for Active Control of High-Speed and High Reynolds Number Flows; Active Flow Control of Lifting Surface With Flap-Current Activities and Future Directions; Closed-Loop Control of Vortex Formation in Separated Flows; Global Instability on Laminar Separation Bubbles-Revisited; Very Large-Scale Motions in Smooth and Rough Wall Boundary Layers; Instability of a Supersonic Boundary-Layer With Localized Roughness; Active Control of Open Cavities; Amplitude Scaling of Active Separation Control; U.S. Air Force Research Laboratory's Need for Flow Physics and Control With Applications Involving Aero-Optics and Weapon Bay Cavities; Some Issues Related to Integrating Active Flow Control With Flight Control; Active Flow Control Strategies Using Surface Pressure Measurements; Reduction of Unsteady Forcing in a Vaned, Contra-Rotating Transonic Turbine Configuration; Active Flow Control Stator With Coanda Surface; Controlling Separation in Turbomachines; Flow Control on Low-Pressure Turbine Airfoils Using Vortex Generator Jets; Reduced Order Modeling Incompressible Flows; Study and Control of Flow Past Disk, and Circular and Rectangular Cylinders Aligned in the Flow; Periodic Forcing of a Turbulent Axisymmetric Wake; Control of Vortex Breakdown in Critical Swirl Regime Using Azimuthal Forcing; External and Turbomachinery Flow Control Working Group; Boundary Layers, Transitions and Separation; Efficiency Considerations in Low Pressure Turbines; Summary of Conference; and Final Plenary Session Transcript.

Development of a home-based training program for post-ward geriatric rehabilitation patients with cognitive impairment: study protocol of a randomized-controlled trail.

PubMed

Bongartz, Martin; Kiss, Rainer; Ullrich, Phoebe; Eckert, Tobias; Bauer, Jürgen; Hauer, Klaus

2017-09-12

Geriatric patients with cognitive impairment (CI) show an increased risk for a negative rehabilitation outcome and reduced functional recovery following inpatient rehabilitation. Despite this obvious demand, evidence-based training programs at the transition from rehabilitation to the home environments are lacking. The aim of this study is to evaluate the efficacy of a feasible and cost-effective home-based training program to improve motor performance and to promote physical activity, specifically-tailored for post-ward geriatric patients with CI. A sample of 101 geriatric patients with mild to moderate stage CI following ward-based rehabilitation will be recruited for a blinded, randomized controlled trial with two arms. The intervention group will conduct a 12 week home-based training, consisting of (1) Exercises to improve strength/power, and postural control; (2) Individual walking trails to enhance physical activity; (3) Implementation of patient-specific motivational strategies to promote behavioral changes. The control group will conduct 12 weeks of unspecific flexibility exercise. Both groups will complete a baseline measurement before starting the program, at the end of the intervention, and after 24 weeks for follow-up. Sensor-based as well as questionnaire-based measures will be applied to comprehensively assess intervention effects. Primary outcomes document motor performance, assessed by the Short Physical Performance Battery, and level of physical activity (PA), as assessed by duration of active episodes (i.e., sum of standing and walking). Secondary outcomes include various medical, psycho-social, various PA and motor outcomes, including sensor-based assessment as well as cost effectiveness. Our study is among the first to provide home-based training in geriatric patients with CI at the transition from a rehabilitation unit to the home environment. The program offers several unique approaches, e.g., a comprehensive and innovative assessment strategy and the integration of individually-tailored motivational strategies. We expect the program to be safe and feasible in geriatric patients with CI with the potential to enhance the sustainability of geriatric rehabilitation programs in patients with CI. International Standard Randomized Controlled Trial (# ISRCTN82378327 ). Registered: August 10, 2015.

Framing Progress In Global Tobacco Control To Inform Action On Noncommunicable Diseases.

PubMed

Wipfli, Heather L; Samet, Jonathan

2015-09-01

Much has been learned about the tobacco epidemic, including its consequences, effective measures to control it, and the actors involved. This article identifies lessons learned that are applicable to the other principal external causes of noncommunicable diseases: alcohol abuse, poor nutrition, and physical inactivity. Among these lessons are the development of evidence-based strategies such as proven cessation methods, tax increases, and smoke-free policies; the role of multinational corporations in maintaining markets and undermining control measures; and the need for strategies that reach across the life course and that begin with individuals and extend to higher levels of societal organization. Differences are also clear. Tobacco products are relatively homogeneous and have no direct benefit to consumers, whereas food and alcohol consumed in moderation are not inherently dangerous. Some tobacco-related diseases have the singular predominant cause of smoking, while many noncommunicable diseases have multiple interlocking causes such as poor diet, excess alcohol consumption, insufficient physical activity, and smoking, along with genetics. Thus, the tobacco control model of comprehensive multilevel strategies is applicable to the control of noncommunicable diseases, but the focus must be on multiple risk factors. Project HOPE—The People-to-People Health Foundation, Inc.

Optochemical Control of Protein Localization and Activity within Cell-like Compartments.

PubMed

Caldwell, Reese M; Bermudez, Jessica G; Thai, David; Aonbangkhen, Chanat; Schuster, Benjamin S; Courtney, Taylor; Deiters, Alexander; Hammer, Daniel A; Chenoweth, David M; Good, Matthew C

2018-05-08

We report inducible dimerization strategies for controlling protein positioning, enzymatic activity, and organelle assembly inside synthetic cell-like compartments upon photostimulation. Using a photocaged TMP-Haloligand compound, we demonstrate small molecule and light-induced dimerization of DHFR and Haloenzyme to localize proteins to a compartment boundary and reconstitute tripartite sfGFP assembly. Using photocaged rapamycin and fragments of split TEV protease fused to FRB and FKBP, we establish optical triggering of protease activity inside cell-size compartments. We apply light-inducible protease activation to initiate assembly of membraneless organelles, demonstrating the applicability of these tools for characterizing cell biological processes in vitro. This modular toolkit, which affords spatial and temporal control of protein function in a minimal cell-like system, represents a critical step toward the reconstitution of a tunable synthetic cell, built from the bottom up.

Does counseling help patients get active? Systematic review of the literature.

PubMed Central

Petrella, Robert J.; Lattanzio, Chastity N.

2002-01-01

OBJECTIVE: To determine the effect of counseling patients to become more physically active. DATA SOURCES: PubMed was searched for articles during the past 30 years on physicians promoting physical activity. Identified studies were cross-referenced, and experts were consulted for additional articles. STUDY SELECTION: Thirteen articles described primary care counseling on exercise. Six studies were randomized controlled trials (RCTs); seven were quasi-experimental designs. Three of the four RCTs and three of the five quasi-experimental studies were short term (4 weeks to 2 months); the remaining three trials lasted longer than 6 months. Most studies used strategies to address stage of change. SYNTHESIS: Outcome measures included adoption of physical activity, stage of change, and change in physical activity level. Most studies found positive relationships between counseling and these outcomes. No reliable evaluation instruments were found, nor was the long-term effect of interventions established. CONCLUSION: Interventions that included written materials for patients, considered behaviour change strategies, and provided training and materials for physicians were effective at increasing levels of physical activity. New strategies that involve measuring and prescribing specific amounts of exercise might also improve fitness levels and hence improve outcomes of chronic disease. Shortcomings of these studies include lack of long-term data, lack of sustaining activities for family physicians, and scant cost-efficacy analysis. PMID:11852615

Strategies for achieving healthy energy balance among African Americans in the Mississippi Delta.

PubMed

Parham, Groesbeck P; Scarinci, Isabel C

2007-10-01

Low-income African Americans who live in rural areas of the Deep South are particularly vulnerable to diseases associated with unhealthy energy imbalance. The Centers for Disease Control and Prevention (CDC) has suggested various physical activity strategies to achieve healthy energy balance. Our objective was to conduct formal, open-ended discussions with low-income African Americans in the Mississippi Delta to determine 1) their dietary habits and physical activity levels, 2) their attitudes toward CDC's suggested physical activity strategies, and 3) their suggestions on how to achieve CDC's strategies within their own environment. A qualitative method (focus groups) was used to conduct the study during 2005. Prestudy meetings were held with African American lay health workers to formulate a focus group topic guide, establish inclusion criteria for focus group participants, select meeting sites and times, and determine group segmentation guidelines. Focus groups were divided into two phases. All discussions and focus group meetings were held in community centers within African American neighborhoods in the Mississippi Delta and were led by trained African American moderators. Phase I focus groups identified the following themes: overeating, low self-esteem, low income, lack of physical exercise, unhealthy methods of food preparation, a poor working definition of healthy energy balance, and superficial knowledge of strategies for achieving healthy energy balance. Phase 2 focus groups identified a preference for social support-based strategies for increasing physical activity levels. Energy balance strategies targeting low-income, rural African Americans in the Deep South may be more effective if they emphasize social interaction at the community and family levels and incorporate the concept of community volunteerism.

Controlling the Seedbeds of Tuberculosis: Diagnosis and Treatment of Tuberculosis Infection

PubMed Central

Rangaka, Molebogeng X.; Cavalcante, Solange C.; Marais, Ben J.; Thim, Sok; Martinson, Neil A.; Swaminathan, Soumya; Chaisson, Richard E.

2015-01-01

The billions of people with latent tuberculosis infection serve as the seedbeds for future cases of active tuberculosis. Virtually all episodes of tuberculosis disease are preceded by a period of asymptomatic Mycobacterium tuberculosis infection; therefore, identifying infected individuals most likely to progress to disease and treating such subclinical infections to prevent future disease provides a critical opportunity to interrupt tuberculosis transmission and reduce the global burden of tuberculosis disease. Programs focusing on single strategies rather than comprehensive programs that deliver an integrated arsenal for tuberculosis control may continue to struggle. Tuberculosis preventive therapy is a poorly utilized tool that is essential for controlling the reservoirs of disease that drive the current epidemic. Comprehensive control strategies that combine preventive therapy for the most high-risk populations and communities with improved case-finding and treatment, control of transmission and health systems strengthening could ultimately lead to worldwide tuberculosis elimination. This paper outlines challenges to implementation of preventive therapy and provides pragmatic suggestions for overcoming them. It further advocates for tuberculosis preventive therapy as the core of a renewed global focus to implement a comprehensive epidemic control strategy that would reduce new tuberculosis cases to elimination targets. This strategy would be underpinned by accelerated research to further understand the biology of subclinical tuberculosis infections, develop novel diagnostics, and drug regimens specifically for subclinical tuberculosis infection, strengthen health systems, community engagement, and enhance sustainable large scale implementation of preventive therapy programs. PMID:26515679

Responding to the active and passive patient: flexibility is the key

PubMed Central

Brown, Rhonda F.; Butow, Phyllis N.; Henman, Michael; Dunn, Stewart M.; Boyle, Francis; Tattersall, Martin H.N.

2002-01-01

Abstract Background  Patients vary widely in their preferences and capacity for participation in medical decision‐making. This study aimed to document oncologist responses to more extreme presentations and identify helpful and unhelpful strategies for clinicians. Patients and methods  A trained actor played the role of a patient with early stage breast cancer who was attending her first consultation with a medical oncologist. She adopted in random order two different consultation participation styles: that of a very anxious, active patient, and that of a depressed, passive patient. Medical consultations between the actor and 16 medical oncologists were videotaped and then analysed qualitatively by two trained raters. Results  Strategies that facilitated shared decision‐making with both patient types and were positively endorsed by the actor/patient included explicit agenda‐setting, active listening, checking understanding, endorsing question‐asking, offering decisional delay, and non‐verbal behaviours conveying empathy and warmth. Oncologists successfully negotiated with the active patient to share control of the consultation, and responded to emotional cues from the passive patient. Unhelpful strategies were also identified. Conclusions  Few clinicians receive training in responding to differing communication styles in their patients that could potentially cause conflict and hinder optimal treatment decision‐making. This study suggests some useful strategies for oncologists to consider, to widen their behavioural repertoire in the cancer consultation. PMID:12199662

A study on the impact of high penetration distributed generation inverters on grid operation and stability

NASA Astrophysics Data System (ADS)

Gu, Fei; Brouwer, Jack; Samuelsen, Scott

2013-09-01

Recent advances in inverter technology have enabled ancillary services such as volt/VAR regulation, SCADA communications, and active power filtering. Smart inverters can not only provide real power, but can be controlled to use excess capacity to provide reactive power compensation, power flow control, and active power filtering without supplementary inverter hardware. A transient level inverter model based on the Solectria 7700 inverter is developed and used to assess these control strategies using field data from an existing branch circuit containing two Amonix 68kW CPV-7700 systems installed at the University of California, Irvine.

Seismic isolation of Advanced LIGO: Review of strategy, instrumentation and performance

NASA Astrophysics Data System (ADS)

Matichard, F.; Lantz, B.; Mittleman, R.; Mason, K.; Kissel, J.; Abbott, B.; Biscans, S.; McIver, J.; Abbott, R.; Abbott, S.; Allwine, E.; Barnum, S.; Birch, J.; Celerier, C.; Clark, D.; Coyne, D.; DeBra, D.; DeRosa, R.; Evans, M.; Foley, S.; Fritschel, P.; Giaime, J. A.; Gray, C.; Grabeel, G.; Hanson, J.; Hardham, C.; Hillard, M.; Hua, W.; Kucharczyk, C.; Landry, M.; Le Roux, A.; Lhuillier, V.; Macleod, D.; Macinnis, M.; Mitchell, R.; O'Reilly, B.; Ottaway, D.; Paris, H.; Pele, A.; Puma, M.; Radkins, H.; Ramet, C.; Robinson, M.; Ruet, L.; Sarin, P.; Shoemaker, D.; Stein, A.; Thomas, J.; Vargas, M.; Venkateswara, K.; Warner, J.; Wen, S.

2015-09-01

The new generation of gravitational waves detectors require unprecedented levels of isolation from seismic noise. This article reviews the seismic isolation strategy and instrumentation developed for the Advanced LIGO observatories. It summarizes over a decade of research on active inertial isolation and shows the performance recently achieved at the Advanced LIGO observatories. The paper emphasizes the scientific and technical challenges of this endeavor and how they have been addressed. An overview of the isolation strategy is given. It combines multiple layers of passive and active inertial isolation to provide suitable rejection of seismic noise at all frequencies. A detailed presentation of the three active platforms that have been developed is given. They are the hydraulic pre-isolator, the single-stage internal isolator and the two-stage internal isolator. The architecture, instrumentation, control scheme and isolation results are presented for each of the three systems. Results show that the seismic isolation sub-system meets Advanced LIGO’s stringent requirements and robustly supports the operation of the two detectors.

A randomised controlled trial of an intervention to facilitate the implementation of healthy eating and physical activity policies and practices in childcare services

PubMed Central

Jones, Jannah; Wolfenden, Luke; Wyse, Rebecca; Finch, Meghan; Yoong, Sze Lin; Dodds, Pennie; Pond, Nicole; Gillham, Karen; Freund, Megan; McElduff, Patrick; Wye, Paula; Wiggers, John

2014-01-01

Introduction Childhood overweight and obesity tracks into adulthood, increasing the risk of developing future chronic disease. Implementing initiatives promoting healthy eating and physical activity in childcare settings has been identified as a priority to prevent excessive child weight gain. Despite this, few trials have been conducted to assess the effectiveness of interventions to support population-wide implementation of such initiatives. The aim of this study is to assess the effectiveness of a multicomponent intervention in increasing the implementation of healthy eating and physical activity policies and practices by centre-based childcare services. Methods and analysis The study will employ a parallel group randomised controlled trial design. A sample of 128 childcare services in the Hunter region of New South Wales, Australia, will be recruited to participate in the trial. 64 services will be randomly allocated to a 12-month implementation intervention. The remaining 64 services will be allocated to a usual care control group. The intervention will consist of a number of strategies to facilitate childcare service implementation of healthy eating and physical activity policies and practices. Intervention strategies will include implementation support staff, securing executive support, consensus processes, staff training, academic detailing visits, performance monitoring and feedback, tools and resources, and a communications strategy. The primary outcome of the trial will be the prevalence of services implementing all healthy eating and physical activity policies and practices targeted by the intervention. To assess the effectiveness of the intervention, telephone surveys with nominated supervisors and room leaders of childcare services will be conducted at baseline and immediately postintervention. Ethics and dissemination The study was approved by the Hunter New England Human Research Ethics Committee and the University of Newcastle Human Research Ethics Committee. Study findings will be disseminated widely through peer-reviewed publications and conference presentations. Trial registration number Australian Clinical Trials Registry ACTRN12612000927820. PMID:24742978

Screening cleavage of Factor XIII V34X Activation Peptides by thrombin mutants: A strategy for controlling fibrin architecture.

PubMed

Jadhav, Madhavi A; Goldsberry, Whitney N; Zink, Sara E; Lamb, Kelsey N; Simmons, Katelyn E; Riposo, Carmela M; Anokhin, Boris A; Maurer, Muriel C

2017-10-01

In blood coagulation, thrombin converts fibrinogen into fibrin monomers that polymerize into a clot network. Thrombin also activates Factor XIII by cleaving the R37-G38 peptide bond of the Activation Peptide (AP) segment. The resultant transglutaminase introduces covalent crosslinks into the fibrin clot. A strategy to modify clot architecture would be to design FXIII AP sequences that are easier or more difficult to be thrombin-cleaved thus controlling initiation of crosslinking. To aid in this design process, FXIII V34X (28-41) Activation Peptides were kinetically ranked for cleavage by wild-type thrombin and several anticoagulant mutants. Thrombin-catalyzed hydrolysis of aromatic FXIII F34, W34, and Y34 APs was compared with V34 and L34. Cardioprotective FXIII L34 remained the variant most readily cleaved by wild-type thrombin. The potent anticoagulant thrombins W215A and W215A/E217A (missing a key substrate platform for binding fibrinogen) were best able to hydrolyze FXIII F34 and W34 APs. Thrombin I174A and L99A could effectively accommodate FXIII W34 and Y34 APs yielding kinetic parameters comparable to FXIII AP L34 with wild-type thrombin. None of the aromatic FXIII V34X APs could be hydrolyzed by thrombin Y60aA. FXIII F34 and W34 are promising candidates for FXIII - anticoagulant thrombin systems that could permit FXIII-catalyzed crosslinking in the presence of reduced fibrin formation. By contrast, FXIII Y34 with thrombin (Y60aA or W215A/E217A) could help assure that both fibrin clot formation and protein crosslinking are hindered. Regulating the activation of FXIII is predicted to be a strategy for helping to control fibrin clot architecture and its neighboring environments. Copyright © 2017 Elsevier B.V. All rights reserved.

Progress of implementation of the World Health Organization strategy for HIV drug resistance control in Latin America and the Caribbean.

PubMed

Ravasi, Giovanni; Jack, Noreen; Alonso Gonzalez, Mónica; Sued, Omar; Pérez-Rosales, María Dolores; Gomez, Bertha; Vila, Marcelo; Riego, Amalia del; Ghidinelli, Massimo

2011-12-01

By the end of 2010, Latin America and the Caribbean (LAC) achieved 63% antiretroviral treatment (ART) coverage. Measures to control HIV drug resistance (HIVDR) at the country level are recommended to maximize the efficacy and sustainability of ART programs. Since 2006, the Pan American Health Organization has supported implementation of the World Health Organization (WHO) strategy for HIVDR prevention and assessment through regional capacity-building activities and direct technical cooperation in 30 LAC countries. By 2010, 85 sites in 19 countries reported early warning indicators, providing information about the extent of potential drivers of drug resistance at the ART site. In 2009, 41.9% of sites did not achieve the WHO target of 100% appropriate first-line prescriptions; 6.3% still experienced high rates (> 20%) of loss to follow-up, and 16.2% had low retention of patients (< 70%) on first-line prescriptions in the first year of treatment. Stock-outs of antiretroviral drugs occurred at 22.7% of sites. Haiti, Guyana, and the Mesoamerican region are planning and implementing WHO HIVDR monitoring surveys or threshold surveys. New HIVDR surveillance tools for concentrated epidemics would promote further scale-up. Extending the WHO HIVDR lab network in Latin America is key to strengthening regional lab capacity to support quality assured HIVDR surveillance. The WHO HIVDR control strategy is feasible and can be rolled out in LAC. Integrating HIVDR activities in national HIV care and treatment plans is key to ensuring the sustainability of this strategy.

Zooming in on children's behavior during delay of gratification: Disentangling impulsigenic and volitional processes underlying self-regulation.

PubMed

Neuenschwander, Regula; Blair, Clancy

2017-02-01

When delaying gratification, both motivational and regulatory processes are likely to be at play; however, the relative contributions of motivational and regulatory influences on delay behavior are unclear. By examining behavioral responses during a delay task, this study sought to examine the motivational (anticipatory behavior) and regulatory mechanisms (executive function and self-control strategies) underlying children's self-regulation. The participants, 65 5- to 9-year-old children (M age =7.19years, SD=0.89), were video-recorded during a delay procedure and later coded for anticipatory behaviors (e.g., gazing intensely at the tablet) and self-control strategies. Children also completed two executive function (EF) tasks. We found that anticipatory behavior was curvilinearly related to delay time. Children showing either very low or very high levels of anticipatory behavior were not able to wait the entire time. Furthermore, our results indicated that anticipatory behavior interacted with EF to predict delay time. Specifically, anticipatory behavior was negatively related to delay time only if EF abilities were low. Finally, self-control strategies also interacted with EF to predict children's ability to delay. Spontaneous engagement in self-control strategies such as fidgeting and engagement in alternative activities were beneficial for children with low EF but were unrelated to delay time for children with high EF. Results indicate the value of examining motivational and regulatory influences on delay behavior. Lapses in self-regulation may be due to the combination of powerful impulsigenic (i.e., anticipatory behavior) and weak volitional processes (i.e., EF, self-control strategies). Copyright © 2016. Published by Elsevier Inc.

Semi-active tuned liquid column damper implementation with real-time hybrid simulations

NASA Astrophysics Data System (ADS)

Riascos, Carlos; Marulanda Casas, Johannio; Thomson, Peter

2016-04-01

Real-time hybrid simulation (RTHS) is a modern cyber-physical technique used for the experimental evaluation of complex systems, that treats the system components with predictable behavior as a numerical substructure and the components that are difficult to model as an experimental substructure. Therefore it is an attractive method for evaluation of the response of civil structures under earthquake, wind and anthropic loads. In this paper, the response of three-story shear frame controlled by a tuned liquid column damper (TLCD) and subject to base excitation is considered. Both passive and semi-active control strategies were implemented and are compared. While the passive TLCD achieved a reduction of 50% in the acceleration response of the main structure in comparison with the structure without control, the semi-active TLCD achieved a reduction of 70%, and was robust to variations in the dynamic properties of the main structure. In addition, a RTHS was implemented with the main structure modeled as a linear, time-invariant (LTI) system through a state space representation and the TLCD, with both control strategies, was evaluated on a shake table that reproduced the displacement of the virtual structure. Current assessment measures for RTHS were used to quantify the performance with parameters such as generalized amplitude, equivalent time delay between the target and measured displacement of the shake table, and energy error using the measured force, and prove that the RTHS described in this paper is an accurate method for the experimental evaluation of structural control systems.

Structural controls on a geothermal system in the Tarutung Basin, north central Sumatra

NASA Astrophysics Data System (ADS)

Nukman, Mochamad; Moeck, Inga

2013-09-01

The Sumatra Fault System provides a unique geologic setting to evaluate the influence of structural controls on geothermal activity. Whereas most of the geothermal systems in Indonesia are controlled by volcanic activity, geothermal systems at the Sumatra Fault System might be controlled by faults and fractures. Exploration strategies for these geothermal systems need to be verified because the typical pattern of heat source and alteration clays are missing so that conventional exploration with magnetotelluric surveys might not provide sufficient data to delineate favorable settings for drilling. We present field geological, structural and geomorphological evidence combined with mapping of geothermal manifestations to allow constraints between fault dynamics and geothermal activity in the Tarutung Basin in north central Sumatra. Our results indicate that the fault pattern in the Tarutung Basin is generated by a compressional stress direction acting at a high angle to the right-lateral Sumatra Fault System. NW-SE striking normal faults possibly related to negative flower structures and NNW-SSE to NNE-SSW oriented dilative Riedel shears are preferential fluid pathways whereas ENE-WSW striking faults act as barriers in this system. The dominant of geothermal manifestations at the eastern part of the basin indicates local extension due to clockwise block rotation in the Sumatra Fault System. Our results support the effort to integrate detailed field geological surveys to refined exploration strategies even in tropical areas where outcrops are limited.

An integrated control strategy for the composite braking system of an electric vehicle with independently driven axles

NASA Astrophysics Data System (ADS)

Sun, Fengchun; Liu, Wei; He, Hongwen; Guo, Hongqiang

2016-08-01

For an electric vehicle with independently driven axles, an integrated braking control strategy was proposed to coordinate the regenerative braking and the hydraulic braking. The integrated strategy includes three modes, namely the hybrid composite mode, the parallel composite mode and the pure hydraulic mode. For the hybrid composite mode and the parallel composite mode, the coefficients of distributing the braking force between the hydraulic braking and the two motors' regenerative braking were optimised offline, and the response surfaces related to the driving state parameters were established. Meanwhile, the six-sigma method was applied to deal with the uncertainty problems for reliability. Additionally, the pure hydraulic mode is activated to ensure the braking safety and stability when the predictive failure of the response surfaces occurs. Experimental results under given braking conditions showed that the braking requirements could be well met with high braking stability and energy regeneration rate, and the reliability of the braking strategy was guaranteed on general braking conditions.

Synchronization and anti-synchronization of a fractional order delayed memristor-based chaotic system using active control

NASA Astrophysics Data System (ADS)

Ding, Dawei; Qian, Xin; Wang, Nian; Liang, Dong

2018-05-01

In this paper, the issue of synchronization and anti-synchronization for fractional-delayed memristor-based chaotic system is studied by using active control strategy. Firstly, some explicit conditions are proposed to guarantee the synchronization and anti-synchronization of the proposed system. Secondly, the influence of order and time delay on the synchronization (anti-synchronization) is discussed. It reveals that synchronization (anti-synchronization) is faster as the order increases or the time delay decreases. Finally, some numerical simulations are presented to verify the validity of our theoretical analysis.

Active control strategy for synchronization and anti-synchronization of a fractional chaotic financial system

NASA Astrophysics Data System (ADS)

Huang, Chengdai; Cao, Jinde

2017-05-01

This paper is concerned with the issues of synchronization and anti-synchronization for fractional chaotic financial system with market confidence by taking advantage of active control approach. Some sufficient conditions are derived to guarantee the synchronization and anti-synchronization for the proposed fractional system. Moreover, the relationship between the order and synchronization(anti-synchronization) is demonstrated numerically. It reveals that synchronization(anti-synchronization) is faster as the order increases. Finally, two illustrative examples are exploited to verify the efficiency of the obtained theoretical results.

Remapping cortical modulation for electrocorticographic brain-computer interfaces: a somatotopy-based approach in individuals with upper-limb paralysis

NASA Astrophysics Data System (ADS)

Degenhart, Alan D.; Hiremath, Shivayogi V.; Yang, Ying; Foldes, Stephen; Collinger, Jennifer L.; Boninger, Michael; Tyler-Kabara, Elizabeth C.; Wang, Wei

2018-04-01

Objective. Brain-computer interface (BCI) technology aims to provide individuals with paralysis a means to restore function. Electrocorticography (ECoG) uses disc electrodes placed on either the surface of the dura or the cortex to record field potential activity. ECoG has been proposed as a viable neural recording modality for BCI systems, potentially providing stable, long-term recordings of cortical activity with high spatial and temporal resolution. Previously we have demonstrated that a subject with spinal cord injury (SCI) could control an ECoG-based BCI system with up to three degrees of freedom (Wang et al 2013 PLoS One). Here, we expand upon these findings by including brain-control results from two additional subjects with upper-limb paralysis due to amyotrophic lateral sclerosis and brachial plexus injury, and investigate the potential of motor and somatosensory cortical areas to enable BCI control. Approach. Individuals were implanted with high-density ECoG electrode grids over sensorimotor cortical areas for less than 30 d. Subjects were trained to control a BCI by employing a somatotopic control strategy where high-gamma activity from attempted arm and hand movements drove the velocity of a cursor. Main results. Participants were capable of generating robust cortical modulation that was differentiable across attempted arm and hand movements of their paralyzed limb. Furthermore, all subjects were capable of voluntarily modulating this activity to control movement of a computer cursor with up to three degrees of freedom using the somatotopic control strategy. Additionally, for those subjects with electrode coverage of somatosensory cortex, we found that somatosensory cortex was capable of supporting ECoG-based BCI control. Significance. These results demonstrate the feasibility of ECoG-based BCI systems for individuals with paralysis as well as highlight some of the key challenges that must be overcome before such systems are translated to the clinical realm. ClinicalTrials.gov Identifier: NCT01393444.

Strategies for Suicide Intervention by Telephone.

ERIC Educational Resources Information Center

Hinson, Jennifer

1982-01-01

Describes techniques helpful for telephone counselors dealing with suicide intervention, including reinstating control, reducing anxiety through problem clarification, and providing hope by active listening and tolerance of dispositions. The use of time-outs and detective work is also discussed. (JAC)

Diagnostics for Hypersonic Engine Control

DTIC Science & Technology

2015-02-01

modeling efforts and/or lead to the development of sensors that can be used as part of scramjet engine control strategies. Activities included work on...of a model scramjet engine cannot rely on the presence of water. Instead, light sources operating at wavelengths resonant with molecular oxygen are...transmitted beam amplitude fluctuations (scintillation). Frequency axis is normalized. Figure 3. Oxygen absorption feature recorded using direct

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

PubMed

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

2016-09-01

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

Active local control of propeller-aircraft run-up noise.

PubMed

Hodgson, Murray; Guo, Jingnan; Germain, Pierre

2003-12-01

Engine run-ups are part of the regular maintenance schedule at Vancouver International Airport. The noise generated by the run-ups propagates into neighboring communities, disturbing the residents. Active noise control is a potentially cost-effective alternative to passive methods, such as enclosures. Propeller aircraft generate low-frequency tonal noise that is highly compatible with active control. This paper presents a preliminary investigation of the feasibility and effectiveness of controlling run-up noise from propeller aircraft using local active control. Computer simulations for different configurations of multi-channel active-noise-control systems, aimed at reducing run-up noise in adjacent residential areas using a local-control strategy, were performed. These were based on an optimal configuration of a single-channel control system studied previously. The variations of the attenuation and amplification zones with the number of control channels, and with source/control-system geometry, were studied. Here, the aircraft was modeled using one or two sources, with monopole or multipole radiation patterns. Both free-field and half-space conditions were considered: for the configurations studied, results were similar in the two cases. In both cases, large triangular quiet zones, with local attenuations of 10 dB or more, were obtained when nine or more control channels were used. Increases of noise were predicted outside of these areas, but these were minimized as more control channels were employed. By combining predicted attenuations with measured noise spectra, noise levels after implementation of an active control system were estimated.

Strategies for enhancing the implementation of school-based policies or practices targeting risk factors for chronic disease.

PubMed

Wolfenden, Luke; Nathan, Nicole K; Sutherland, Rachel; Yoong, Sze Lin; Hodder, Rebecca K; Wyse, Rebecca J; Delaney, Tessa; Grady, Alice; Fielding, Alison; Tzelepis, Flora; Clinton-McHarg, Tara; Parmenter, Benjamin; Butler, Peter; Wiggers, John; Bauman, Adrian; Milat, Andrew; Booth, Debbie; Williams, Christopher M

2017-11-29

A number of school-based policies or practices have been found to be effective in improving child diet and physical activity, and preventing excessive weight gain, tobacco or harmful alcohol use. Schools, however, frequently fail to implement such evidence-based interventions. The primary aims of the review are to examine the effectiveness of strategies aiming to improve the implementation of school-based policies, programs or practices to address child diet, physical activity, obesity, tobacco or alcohol use.Secondary objectives of the review are to: Examine the effectiveness of implementation strategies on health behaviour (e.g. fruit and vegetable consumption) and anthropometric outcomes (e.g. BMI, weight); describe the impact of such strategies on the knowledge, skills or attitudes of school staff involved in implementing health-promoting policies, programs or practices; describe the cost or cost-effectiveness of such strategies; and describe any unintended adverse effects of strategies on schools, school staff or children. All electronic databases were searched on 16 July 2017 for studies published up to 31 August 2016. We searched the following electronic databases: Cochrane Library including the Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations; Embase Classic and Embase; PsycINFO; Education Resource Information Center (ERIC); Cumulative Index to Nursing and Allied Health Literature (CINAHL); Dissertations and Theses; and SCOPUS. We screened reference lists of all included trials for citations of other potentially relevant trials. We handsearched all publications between 2011 and 2016 in two specialty journals (Implementation Science and Journal of Translational Behavioral Medicine) and conducted searches of the WHO International Clinical Trials Registry Platform (ICTRP) (http://apps.who.int/trialsearch/) as well as the US National Institutes of Health registry (https://clinicaltrials.gov). We consulted with experts in the field to identify other relevant research. 'Implementation' was defined as the use of strategies to adopt and integrate evidence-based health interventions and to change practice patterns within specific settings. We included any trial (randomised or non-randomised) conducted at any scale, with a parallel control group that compared a strategy to implement policies or practices to address diet, physical activity, overweight or obesity, tobacco or alcohol use by school staff to 'no intervention', 'usual' practice or a different implementation strategy. Citation screening, data extraction and assessment of risk of bias was performed by review authors in pairs. Disagreements between review authors were resolved via consensus, or if required, by a third author. Considerable trial heterogeneity precluded meta-analysis. We narratively synthesised trial findings by describing the effect size of the primary outcome measure for policy or practice implementation (or the median of such measures where a single primary outcome was not stated). We included 27 trials, 18 of which were conducted in the USA. Nineteen studies employed randomised controlled trial (RCT) designs. Fifteen trials tested strategies to implement healthy eating policies, practice or programs; six trials tested strategies targeting physical activity policies or practices; and three trials targeted tobacco policies or practices. Three trials targeted a combination of risk factors. None of the included trials sought to increase the implementation of interventions to delay initiation or reduce the consumption of alcohol. All trials examined multi-strategic implementation strategies and no two trials examined the same combinations of implementation strategies. The most common implementation strategies included educational materials, educational outreach and educational meetings. For all outcomes, the overall quality of evidence was very low and the risk of bias was high for the majority of trials for detection and performance bias.Among 13 trials reporting dichotomous implementation outcomes-the proportion of schools or school staff (e.g. classes) implementing a targeted policy or practice-the median unadjusted (improvement) effect sizes ranged from 8.5% to 66.6%. Of seven trials reporting the percentage of a practice, program or policy that had been implemented, the median unadjusted effect (improvement), relative to the control ranged from -8% to 43%. The effect, relative to control, reported in two trials assessing the impact of implementation strategies on the time per week teachers spent delivering targeted policies or practices ranged from 26.6 to 54.9 minutes per week. Among trials reporting other continuous implementation outcomes, findings were mixed. Four trials were conducted of strategies that sought to achieve implementation 'at scale', that is, across samples of at least 50 schools, of which improvements in implementation were reported in three trials.The impact of interventions on student health behaviour or weight status were mixed. Three of the eight trials with physical activity outcomes reported no significant improvements. Two trials reported reductions in tobacco use among intervention relative to control. Seven of nine trials reported no between-group differences on student overweight, obesity or adiposity. Positive improvements in child dietary intake were generally reported among trials reporting these outcomes. Three trials assessed the impact of implementation strategies on the attitudes of school staff and found mixed effects. Two trials specified in the study methods an assessment of potential unintended adverse effects, of which, they reported none. One trial reported implementation support did not significantly increase school revenue or expenses and another, conducted a formal economic evaluation, reporting the intervention to be cost-effective. Trial heterogeneity, and the lack of consistent terminology describing implementation strategies, were important limitations of the review. Given the very low quality of the available evidence, it is uncertain whether the strategies tested improve implementation of the targeted school-based policies or practices, student health behaviours, or the knowledge or attitudes of school staff. It is also uncertain if strategies to improve implementation are cost-effective or if they result in unintended adverse consequences. Further research is required to guide efforts to facilitate the translation of evidence into practice in this setting.

Effects of congruent and incongruent visual cues on speech perception and brain activity in cochlear implant users.

PubMed

Song, Jae-Jin; Lee, Hyo-Jeong; Kang, Hyejin; Lee, Dong Soo; Chang, Sun O; Oh, Seung Ha

2015-03-01

While deafness-induced plasticity has been investigated in the visual and auditory domains, not much is known about language processing in audiovisual multimodal environments for patients with restored hearing via cochlear implant (CI) devices. Here, we examined the effect of agreeing or conflicting visual inputs on auditory processing in deaf patients equipped with degraded artificial hearing. Ten post-lingually deafened CI users with good performance, along with matched control subjects, underwent H 2 (15) O-positron emission tomography scans while carrying out a behavioral task requiring the extraction of speech information from unimodal auditory stimuli, bimodal audiovisual congruent stimuli, and incongruent stimuli. Regardless of congruency, the control subjects demonstrated activation of the auditory and visual sensory cortices, as well as the superior temporal sulcus, the classical multisensory integration area, indicating a bottom-up multisensory processing strategy. Compared to CI users, the control subjects exhibited activation of the right ventral premotor-supramarginal pathway. In contrast, CI users activated primarily the visual cortices more in the congruent audiovisual condition than in the null condition. In addition, compared to controls, CI users displayed an activation focus in the right amygdala for congruent audiovisual stimuli. The most notable difference between the two groups was an activation focus in the left inferior frontal gyrus in CI users confronted with incongruent audiovisual stimuli, suggesting top-down cognitive modulation for audiovisual conflict. Correlation analysis revealed that good speech performance was positively correlated with right amygdala activity for the congruent condition, but negatively correlated with bilateral visual cortices regardless of congruency. Taken together these results suggest that for multimodal inputs, cochlear implant users are more vision-reliant when processing congruent stimuli and are disturbed more by visual distractors when confronted with incongruent audiovisual stimuli. To cope with this multimodal conflict, CI users activate the left inferior frontal gyrus to adopt a top-down cognitive modulation pathway, whereas normal hearing individuals primarily adopt a bottom-up strategy.

Bioengineering Strategies for Designing Targeted Cancer Therapies

PubMed Central

Wen, Xuejun

2014-01-01

The goals of bioengineering strategies for targeted cancer therapies are (1) to deliver a high dose of an anticancer drug directly to a cancer tumor, (2) to enhance drug uptake by malignant cells, and (3) to minimize drug uptake by nonmalignant cells. Effective cancer-targeting therapies will require both passive- and active targeting strategies and a thorough understanding of physiologic barriers to targeted drug delivery. Designing a targeted therapy includes the selection and optimization of a nanoparticle delivery vehicle for passive accumulation in tumors, a targeting moiety for active receptor-mediated uptake, and stimuli-responsive polymers for control of drug release. The future direction of cancer targeting is a combinatorial approach, in which targeting therapies are designed to use multiple targeting strategies. The combinatorial approach will enable combination therapy for delivery of multiple drugs and dual ligand targeting to improve targeting specificity. Targeted cancer treatments in development and the new combinatorial approaches show promise for improving targeted anticancer drug delivery and improving treatment outcomes. PMID:23768509

A cluster randomized control trial to assess the impact of active learning on child activity, attention control, and academic outcomes: The Texas I-CAN trial.

PubMed

Bartholomew, John B; Jowers, Esbelle M; Errisuriz, Vanessa L; Vaughn, Sharon; Roberts, Gregory

2017-10-01

Active learning is designed to pair physical activity with the teaching of academic content. This has been shown to be a successful strategy to increase physical activity and improve academic performance. The existing designs have confounded academic lessons with physical activity. As a result, it is impossible to determine if the subsequent improvement in academic performance is due to: (1) physical activity, (2) the academic content of the active learning, or (3) the combination of academic material taught through physical activity. The Texas I-CAN project is a 3-arm, cluster randomized control trial in which 28 elementary schools were assigned to either control, math intervention, or spelling intervention. As a result, each intervention condition serves as an unrelated content control for the other arm of the trial, allowing the impact of physical activity to be separated from the content. That is, schools that perform only active math lessons provide a content control for the spelling schools on spelling outcomes. This also calculated direct observations of attention and behavior control following periods of active learning. This design is unique in its ability to separate the impact of physical activity, in general, from the combination of physical activity and specific academic content. This, in combination with the ability to examine both proximal and distal outcomes along with measures of time on task will do much to guide the design of future, school-based interventions. Copyright © 2017 Elsevier Inc. All rights reserved.

Wildfire mitigation strategies affect soil enzyme activity and soil organic carbon in loblolly pine (Pinus taeda) forests

Treesearch

R.E.J. Boerner; T.A. Waldrop; V.B. Shelburne

2006-01-01

We quantified the effects of three wildfire hazard reduction treatments (prescribed fire, thinning from below, and the combination of fire and thinning), and passive management (control) on mineral soil organic C, and enzyme activity in loblolly pine (Pinus taeda L.) forests on the Piedmont of South Carolina. Soil organic C was reduced by thinning,...

Can Young Children Make Active Choices? Outcomes of a Feasibility Trial in Seven-Year-Old Children

ERIC Educational Resources Information Center

Hands, Beth; Larkin, Dawne; Rose, Elizabeth; Parker, Helen; Smith, Anne

2011-01-01

This project evaluated the feasibility of a child-centred 24-week physical activity intervention. The "Play5" strategy encourages children to choose to play vigorously five times a day for about as long as school recess. The seven-year-old children were randomised to control (n = 176) or intervention groups (n = 132). Data were collected…

Finite Control Set Model Predictive Control for Multiple Distributed Generators Microgrids

NASA Astrophysics Data System (ADS)

Babqi, Abdulrahman Jamal

This dissertation proposes two control strategies for AC microgrids that consist of multiple distributed generators (DGs). The control strategies are valid for both grid-connected and islanded modes of operation. In general, microgrid can operate as a stand-alone system (i.e., islanded mode) or while it is connected to the utility grid (i.e., grid connected mode). To enhance the performance of a micrgorid, a sophisticated control scheme should be employed. The control strategies of microgrids can be divided into primary and secondary controls. The primary control regulates the output active and reactive powers of each DG in grid-connected mode as well as the output voltage and frequency of each DG in islanded mode. The secondary control is responsible for regulating the microgrid voltage and frequency in the islanded mode. Moreover, it provides power sharing schemes among the DGs. In other words, the secondary control specifies the set points (i.e. reference values) for the primary controllers. In this dissertation, Finite Control Set Model Predictive Control (FCS-MPC) was proposed for controlling microgrids. FCS-MPC was used as the primary controller to regulate the output power of each DG (in the grid-connected mode) or the voltage of the point of DG coupling (in the islanded mode of operation). In the grid-connected mode, Direct Power Model Predictive Control (DPMPC) was implemented to manage the power flow between each DG and the utility grid. In the islanded mode, Voltage Model Predictive Control (VMPC), as the primary control, and droop control, as the secondary control, were employed to control the output voltage of each DG and system frequency. The controller was equipped with a supplementary current limiting technique in order to limit the output current of each DG in abnormal incidents. The control approach also enabled smooth transition between the two modes. The performance of the control strategy was investigated and verified using PSCAD/EMTDC software platform. This dissertation also proposes a control and power sharing strategy for small-scale microgrids in both grid-connected and islanded modes based on centralized FCS-MPC. In grid-connected mode, the controller was capable of managing the output power of each DG and enabling flexible power regulation between the microgrid and the utility grid. In islanded mode, the controller regulated the microgrid voltage and frequency, and provided a precise power sharing scheme among the DGs. In addition, the power sharing can be adjusted flexibly by changing the sharing ratio. The proposed control also enabled plug-and-play operation. Moreover, a smooth transition between the two modes of operation was achieved without any disturbance in the system. Case studies were carried out in order to validate the proposed control strategy with the PSCAD/EMTDA software package.

‘I’m not a smoker…yet’: a qualitative study on perceptions of tobacco control in Chinese high schools

PubMed Central

2018-01-01

Objective Chinese adolescents’ perceptions about tobacco control at schools are rarely researched. We explored how current antismoking strategies work in middle school environments, as well as the attitudes towards these strategies held by students and teaching staff members. Methods Four focus groups (24 eleventh graders; M age=16 years) and five indepth interviews (teaching staff members with tobacco control experience in schools) were conducted in Kunming, Yunnan Province, China. We used thematic analysis combining inductive and deductive processes, along with field observations and research group discussions, for data analysis. Results With educational approaches and practical strategies, antismoking education reported in the middle schools had limited effectiveness. Although smoking is banned in schools, students can circumvent schools’ controls easily. Notably salient is the pessimistic attitude towards school-based antismoking strategies at school. Detrimental influences within (teachers’ smoking) and beyond schools (high societal smoking prevalence) largely challenged the efforts to manage students’ smoking. Conclusions Current antismoking approaches in schools fail to curb smoking among Chinese high school students. Their effectiveness is undermined by both within-campus and off-campus influences. Students’ perceptions of smoking should be valued as their knowledge of smoking is actively constructed. Future antismoking education at school should incorporate interactive sessions rather than merely didactic approaches about the harms of smoking. Although stricter rules for teachers’ smoking are needed, complementary strategies such as population-level interventions and policy measures in wider society will assist in efforts within schools. PMID:29678968

Availability Control for Means of Transport in Decisive Semi-Markov Models of Exploitation Process

NASA Astrophysics Data System (ADS)

Migawa, Klaudiusz

2012-12-01

The issues presented in this research paper refer to problems connected with the control process for exploitation implemented in the complex systems of exploitation for technical objects. The article presents the description of the method concerning the control availability for technical objects (means of transport) on the basis of the mathematical model of the exploitation process with the implementation of the decisive processes by semi-Markov. The presented method means focused on the preparing the decisive for the exploitation process for technical objects (semi-Markov model) and after that specifying the best control strategy (optimal strategy) from among possible decisive variants in accordance with the approved criterion (criteria) of the activity evaluation of the system of exploitation for technical objects. In the presented method specifying the optimal strategy for control availability in the technical objects means a choice of a sequence of control decisions made in individual states of modelled exploitation process for which the function being a criterion of evaluation reaches the extreme value. In order to choose the optimal control strategy the implementation of the genetic algorithm was chosen. The opinions were presented on the example of the exploitation process of the means of transport implemented in the real system of the bus municipal transport. The model of the exploitation process for the means of transports was prepared on the basis of the results implemented in the real transport system. The mathematical model of the exploitation process was built taking into consideration the fact that the model of the process constitutes the homogenous semi-Markov process.

Psychological interventions influence patients' attitudes and beliefs about their chronic pain.

PubMed

Vanhaudenhuyse, Audrey; Gillet, Aline; Malaise, Nicole; Salamun, Irène; Grosdent, Stéphanie; Maquet, Didier; Nyssen, Anne-Sophie; Faymonville, Marie-Elisabeth

2018-04-01

Patients' changing attitudes and beliefs about pain are considered as improvements in the treatment of chronic pain. Multidisciplinary approaches to pain allow modifications of coping strategies of patients, from passive to active. We investigate how two therapeutic treatments impact patients' attitudes and beliefs regarding pain, as measured with the Survey of Pain Attitudes (SOPA). We allocated 415 patients with chronic pain either to psychoeducation combined with physiotherapy, self-hypnosis combined with self-care learning, or to control groups. Pain intensity, global impression of change, and beliefs and attitudes regarding pain were assessed before and after treatment. Our main results showed a significant effect of psychoeducation/physiotherapy on control, harm, and medical cure SOPA subscales; and a significant effect of self-hypnosis/self-care on control, disability and medical cure subscales. Correlation results showed that pain perception was negatively associated with control, while positively associated with disability, and a belief that hurt signifies harm. Patients' impression of improvement was associated with greater control, lower disability, and lower belief that hurt signifies harm. The present study showed that self-hypnosis/self-care and psychoeducation/physiotherapy were associated with patients' evolution of coping strategies from passive to active, allowing them to reduce pain perception and improve their global impression of treatment effectiveness.

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

PubMed

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

2016-05-01

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

Comparison between different sets of suspension parameters and introduction of new modified skyhook control strategy incorporating varying road condition

NASA Astrophysics Data System (ADS)

Abul Kashem, Saad Bin; Ektesabi, Mehran; Nagarajah, Romesh

2012-07-01

This study examines the uncertainties in modelling a quarter car suspension system caused by the effect of different sets of suspension parameters of a corresponding mathematical model. To overcome this problem, 11 sets of identified parameters of a suspension system have been compared, taken from the most recent published work. From this investigation, a set of parameters were chosen which showed a better performance than others in respect of peak amplitude and settling time. These chosen parameters were then used to investigate the performance of a new modified continuous skyhook control strategy with adaptive gain that dictates the vehicle's semi-active suspension system. The proposed system first captures the road profile input over a certain period. Then it calculates the best possible value of the skyhook gain (SG) for the subsequent process. Meanwhile the system is controlled according to the new modified skyhook control law using an initial or previous value of the SG. In this study, the proposed suspension system is compared with passive and other recently reported skyhook controlled semi-active suspension systems. Its performances have been evaluated in terms of ride comfort and road handling performance. The model has been validated in accordance with the international standards of admissible acceleration levels ISO2631 and human vibration perception.

Prevention of problem behavior by teaching functional communication and self-control skills to preschoolers.

PubMed

Luczynski, Kevin C; Hanley, Gregory P

2013-01-01

We evaluated the effects of the preschool life skills program (PLS; Hanley, Heal, Tiger, & Ingvarsson, 2007) on the acquisition and maintenance of functional communication and self-control skills, as well as its effect on problem behavior, of small groups of preschoolers at risk for school failure. Six children were taught to request teacher attention, teacher assistance, and preferred materials, and to tolerate delays to and denial of those events during child-led, small-group activities. Teaching strategies included instruction, modeling, role play, and differential reinforcement. Six additional children randomly assigned to similarly sized control groups participated in small-group activities but did not experience the PLS program. Within-subject and between-groups designs showed that the PLS teaching procedures were functionally related to the improvements and maintenance of the skills and prevention of problem behavior. Stakeholder responses on a social acceptability questionnaire indicated that they were satisfied with the form of the targeted social skills, the improvements in the children's performance, and the teaching strategies. © Society for the Experimental Analysis of Behavior.