Possible application of a nematophagous fungus as a biological control agent of parasitic nematodes on commercial sheep farms in South Africa.

PubMed

Faedo, M; Krecek, R C

2002-03-01

Biological control of parasitic nematodes of livestock is currently under development and represents another tool that may be integrated into helminth parasite control strategies. This paper presents a brief introduction to commercial sheep farming in South Africa and currently available nematode parasite control methods. These include the FAMACHA clinical assay, strategies of pasture management, dilution of resistant worm species by introduction of susceptible worms, breed resistant sheep and nutritional supplementation. The purpose of this paper is to outline the principles of biological control using nematophagous fungi and how it may be applied on sheep farms in South Africa.

Evaluation of bovine viral diarrhoea virus control strategies in dairy herds in Hokkaido, Japan, using stochastic modelling.

PubMed

Sekiguchi, S; Presi, P; Omori, R; Staerk, K; Schuppers, M; Isoda, N; Yoshikawa, Y; Umemura, T; Nakayama, H; Fujii, Y; Sakoda, Y

2018-02-01

Bovine viral diarrhoea virus (BVDV) infection in cattle can result in growth retardation, reduced milk production, reproductive disorders and death. Persistently infected animals are the primary source of infection. In Hokkaido, Japan, all cattle entering shared pastures in summer are vaccinated before movement for disease control. Additionally, these cattle may be tested for BVDV and culled if positive. However, the effectiveness of this control strategy aiming to reduce the number of BVDV-infected animals has not been assessed. The aim of this study was to evaluate the effectiveness of various test-and-cull and/or vaccination strategies on BVDV control in dairy farms in two districts of Hokkaido, Nemuro and Hiyama. A stochastic model was developed to compare the different control strategies over a 10-year period. The model was individual-based and simulated disease dynamics both within and between herds. Parameters included in the model were obtained from the literature, the Hokkaido government and the Japanese Ministry of Agriculture, Forestry and Fisheries. Nine different scenarios were compared as follows: no control, test-and-cull strategies based on antigen testing of either calves or only cattle entering common pastures, vaccination of all adult cattle or only cattle entering shared pastures and combinations thereof. The results indicate that current strategies for BVDV control in Hokkaido slightly reduced the number of BVDV-infected animals; however, alternative strategies such as testing all calves and culling any positives or vaccinating all susceptible adult animals dramatically reduced those. To our knowledge, this is the first report regarding the comparison of the effectiveness between the current strategies in Hokkaido and the alternative strategies for BVDV control measures. © 2017 Blackwell Verlag GmbH.

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

Exposure control strategies in the carbonaceous nanomaterial industry.

PubMed

Dahm, Matthew M; Yencken, Marianne S; Schubauer-Berigan, Mary K

2011-06-01

Little is known about exposure control strategies currently being implemented to minimize exposures during the production or use of nanomaterials in the United States. Our goal was to estimate types and quantities of materials used and factors related to workplace exposure reductions among companies manufacturing or using engineered carbonaceous nanomaterials (ECNs). Information was collected through phone surveys on work practices and exposure control strategies from 30 participating producers and users of ECN. The participants were classified into three groups for further examination. We report here the use of exposure control strategies. Observed patterns suggest that large-scale manufacturers report greater use of nanospecific exposure control strategies particularly for respiratory protection. Workplaces producing or using ECN generally report using engineering and administrative controls as well as personal protective equipment to control workplace employee exposure.

Research on control strategy based on fuzzy PR for grid-connected inverter

NASA Astrophysics Data System (ADS)

Zhang, Qian; Guan, Weiguo; Miao, Wen

2018-04-01

In the traditional PI controller, there is static error in tracking ac signals. To solve the problem, the control strategy of a fuzzy PR and the grid voltage feed-forward is proposed. The fuzzy PR controller is to eliminate the static error of the system. It also adjusts parameters of PR controller in real time, which avoids the defect of fixed parameter fixed. The grid voltage feed-forward control can ensure the quality of current and improve the system's anti-interference ability when the grid voltage is distorted. Finally, the simulation results show that the system can output grid current with good quality and also has good dynamic and steady state performance.

Instantaneous Project Controls: Current Status, State of the Art, Benefits, and Strategies

ERIC Educational Resources Information Center

Abbaszadegan, Amin

2016-01-01

Despite advancements in construction and construction-related technology, capital project performance deviations, typically overruns, remain endemic within the capital projects industry. Currently, management is generally unaware of the current status of their projects, and thus monitoring and control of projects are not achieved effectively. In…

Research on the Control Strategy for Grid-side Converter of PWM Doubly Fed Induction Wind Power Generators

NASA Astrophysics Data System (ADS)

Liu, Yifang; Wang, Zhijie; Li, Renfu; Jiang, Xiuchen; Sheng, Gehao; Liu, Tianyu; Liu, Sanming

2017-05-01

When the grid voltage drop, over current of transient rotor and over voltage may damage the power electronic devices. The attenuation of electromagnetic torque will lead to speed up. This paper proposes an improved feed-forward control strategy and its application in the PWM converter. When the PWM converter on voltage drops, bus voltage will be more stable. So over current problems of the DFIG rotor side can be reduced, and it also can improve voltage regulation speed of the DC bus voltage and reduce the oscillation amplitude. Furthermore, the stability of doubly fed wind generator system can be improved. The simulation results verify the validity of the modified control strategy.

Initial Assessment of the Acceptability of a Push-Pull Aedes aegypti Control Strategy in Iquitos, Peru and Kanchanaburi, Thailand

PubMed Central

Paz-Soldan, Valerie A.; Plasai, Valaikanya; Morrison, Amy C.; Rios-Lopez, Esther J.; Guedez-Gonzales, Shirly; Grieco, John P.; Mundal, Kirk; Chareonviriyaphap, Theeraphap; Achee, Nicole L.

2011-01-01

As part of a larger research program evaluating chemical threshold levels for a Push-Pull intervention to reduce man-vector (Aedes aegypti) contact, this qualitative study explored local perceptions and strategies associated with mosquito control within dengue-endemic communities in Peru and Thailand. Focus groups were used to provide preliminary information that would identify possible public acceptance issues to the Push-Pull strategy in each site. Nine focus group discussions (total of 102 individuals) conducted between September 2008 and March 2009 examined several themes: 1) current mosquito control practices; 2) perceptions of spatial repellency and contact irritancy versus killing mosquitoes; and 3) initial perceptions toward mosquito host-seeking traps. Results indicate participants use household-level strategies for insect control that reveal familiarity with the concept of spatial repellent and contact irritant actions of chemicals and that placing traps in the peridomestic environment to remove repelled mosquitoes was acceptable. Preliminary evidence suggests a Push-Pull strategy should be well accepted in these locations. These results will be beneficial for developing future large scale push-pull interventions and are currently being used to guide insecticide application strategies in (entomological) proof-of-concept studies using experimental huts. PMID:21292886

Malaria on the Guiana Shield: a review of the situation in French Guiana

PubMed Central

Musset, Lise; Pelleau, Stéphane; Girod, Romain; Ardillon, Vanessa; Carvalho, Luisiane; Dusfour, Isabelle; Gomes, Margarete SM; Djossou, Félix; Legrand, Eric

2014-01-01

In a climate of growing concern that Plasmodium falciparum may be developing a drug resistance to artemisinin derivatives in the Guiana Shield, this review details our current knowledge of malaria and control strategy in one part of the Shield, French Guiana. Local epidemiology, test-treat-track strategy, the state of parasite drug resistance and vector control measures are summarised. Current issues in terms of mobile populations and legislative limitations are also discussed. PMID:25184998

Prevention and Control Strategies to Counter Dengue Virus Infection

PubMed Central

Rather, Irfan A.; Parray, Hilal A.; Lone, Jameel B.; Paek, Woon K.; Lim, Jeongheui; Bajpai, Vivek K.; Park, Yong-Ha

2017-01-01

Dengue is currently the highest and rapidly spreading vector-borne viral disease, which can lead to mortality in its severe form. The globally endemic dengue poses as a public health and economic challenge that has been attempted to suppress though application of various prevention and control techniques. Therefore, broad spectrum techniques, that are efficient, cost-effective, and environmentally sustainable, are proposed and practiced in dengue-endemic regions. The development of vaccines and immunotherapies have introduced a new dimension for effective dengue control and prevention. Thus, the present study focuses on the preventive and control strategies that are currently employed to counter dengue. While traditional control strategies bring temporary sustainability alone, implementation of novel biotechnological interventions, such as sterile insect technique, paratransgenesis, and production of genetically modified vectors, has improved the efficacy of the traditional strategies. Although a large-scale vector control strategy can be limited, innovative vaccine candidates have provided evidence for promising dengue prevention measures. The use of tetravalent dengue vaccine (CYD-TDV) has been the most effective so far in treating dengue infections. Nonetheless, challenges and limitation hinder the progress of developing integrated intervention methods and vaccines; while the improvement in the latest techniques and vaccine formulation continues, one can hope for a future without the threat of dengue virus. PMID:28791258

Prevention and Control Strategies to Counter Dengue Virus Infection.

PubMed

Rather, Irfan A; Parray, Hilal A; Lone, Jameel B; Paek, Woon K; Lim, Jeongheui; Bajpai, Vivek K; Park, Yong-Ha

2017-01-01

Dengue is currently the highest and rapidly spreading vector-borne viral disease, which can lead to mortality in its severe form. The globally endemic dengue poses as a public health and economic challenge that has been attempted to suppress though application of various prevention and control techniques. Therefore, broad spectrum techniques, that are efficient, cost-effective, and environmentally sustainable, are proposed and practiced in dengue-endemic regions. The development of vaccines and immunotherapies have introduced a new dimension for effective dengue control and prevention. Thus, the present study focuses on the preventive and control strategies that are currently employed to counter dengue. While traditional control strategies bring temporary sustainability alone, implementation of novel biotechnological interventions, such as sterile insect technique, paratransgenesis, and production of genetically modified vectors, has improved the efficacy of the traditional strategies. Although a large-scale vector control strategy can be limited, innovative vaccine candidates have provided evidence for promising dengue prevention measures. The use of tetravalent dengue vaccine (CYD-TDV) has been the most effective so far in treating dengue infections. Nonetheless, challenges and limitation hinder the progress of developing integrated intervention methods and vaccines; while the improvement in the latest techniques and vaccine formulation continues, one can hope for a future without the threat of dengue virus.

Battery charging and discharging research based on the interactive technology of smart grid and electric vehicle

NASA Astrophysics Data System (ADS)

Zhang, Mingyang

2018-06-01

To further study the bidirectional flow problem of V2G (Vehicle to Grid) charge and discharge motor, the mathematical model of AC/DC converter and bi-directional DC/DC converter was established. Then, lithium battery was chosen as the battery of electric vehicle and its mathematical model was established. In order to improve the service life of lithium battery, bidirectional DC/DC converter adopted constant current and constant voltage control strategy. In the initial stage of charging, constant current charging was adopted with current single closed loop control. After reaching a certain value, voltage was switched to constant voltage charging controlled by voltage and current. Subsequently, the V2G system simulation model was built in MATLAB/Simulink. The simulation results verified the correctness of the control strategy and showed that when charging, constant current and constant voltage charging was achieved, the grid side voltage and current were in the same phase, and the power factor was about 1. When discharging, the constant current discharge was applied, and the grid voltage and current phase difference was r. To sum up, the simulation results are correct and helpful.

A computer simulation approach to measurement of human control strategy

NASA Technical Reports Server (NTRS)

Green, J.; Davenport, E. L.; Engler, H. F.; Sears, W. E., III

1982-01-01

Human control strategy is measured through use of a psychologically-based computer simulation which reflects a broader theory of control behavior. The simulation is called the human operator performance emulator, or HOPE. HOPE was designed to emulate control learning in a one-dimensional preview tracking task and to measure control strategy in that setting. When given a numerical representation of a track and information about current position in relation to that track, HOPE generates positions for a stick controlling the cursor to be moved along the track. In other words, HOPE generates control stick behavior corresponding to that which might be used by a person learning preview tracking.

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…

A dual-loop adaptive control for minimizing time response delay in real-time structural vibration control with magnetorheological (MR) devices

NASA Astrophysics Data System (ADS)

Chen, Xi; Li, Yancheng; Li, Jianchun; Gu, Xiaoyu

2018-01-01

Time delay is a challenge issue faced by the real-time control application of the magnetorheological (MR) devices. Not to deal with it properly may jeopardize the effectiveness of the control, even lead to instability of the control system or catastrophic failure. This paper proposes a dual-loop adaptive control to address the response time delay associated with MR devices. In the proposed dual-loop control, the inner loop is designed to compensate the time delay of MR device induced by the PWM current driver. While the outer loop control can be any structural control algorithm with aims to reducing structural responses of a building during extreme loadings. Here an adaptive control strategy is adopted. To verify the proposed dual-loop control, a smart base isolation system employing magnetorheological elastomer base isolators is used as an example to illustrate the control effect. Numerical study is then conducted using a 5 -storey shear building model equipped with smart base isolation system. The result shows that with the implementation of the inner loop, the control current can instantly follow the control command which reduce the possibility of instability caused by the time delay. Comparative studies are conducted between three control strategies, i.e. dual-loop control, Lyapunov’s direct method based control and optimal passive base isolation control. The results of the study have demonstrated that the proposed dual-loop control strategy can achieve much better performance than the other two control strategies.

Managing Work and Family: Do Control Strategies Help?

ERIC Educational Resources Information Center

Versey, H. Shellae

2015-01-01

How can we effectively manage competing obligations from work and family without becoming overwhelmed? This question inspires the current study by examining control strategies that may facilitate better work-life balance, with a specific focus on the role of lowered aspirations and positive reappraisals, attitudes that underlie adaptive coping…

Current status and strategies for viral hepatitis control in Korea.

PubMed

Sinn, Dong Hyun; Cho, Eun Ju; Kim, Ji Hoon; Kim, Do Young; Kim, Yoon Jun; Choi, Moon Seok

2017-09-01

Viral hepatitis is one of major global health challenges with increasing disease burden worldwide. Hepatitis B virus and hepatitis C virus infections are major causes of chronic liver diseases. They can lead to cirrhosis, hepatocellular carcinoma, and death in significant portion of affected people. Transmission of hepatitis B virus can be blocked by vaccination. Progression of hepatitis B virus-related liver diseases can be prevented by long-term viral suppression with effective drugs. Although vaccine for hepatitis C virus is currently unavailable, hepatitis C virus infection can be eradicated by oral direct antiviral agents. To eliminate viral hepatitis, World Health Organization (WHO) has urged countries to develop national goals and targets through reducing 90% of new infections and providing universal access to key treatment services up to 80%. This can lead to 65% reduction of viral hepatitis-related mortality. Here, we discuss some key features of viral hepatitis, strategies to control viral hepatitis suggested by WHO, and current status and strategies for viral hepatitis control in South Korea. To achieve the goal of viral hepatitis elimination by 2030 in South Korea, an independent 'viral hepatitis sector' in Centers for Disease Control & Prevention (CDC) needs to be established to organize and execute comprehensive strategy for the management of viral hepatitis in South Korea.

River Blindness: Mathematical Models for Control and Elimination.

PubMed

Basáñez, M G; Walker, M; Turner, H C; Coffeng, L E; de Vlas, S J; Stolk, W A

2016-01-01

Human onchocerciasis (river blindness) is one of the few neglected tropical diseases (NTDs) whose control strategies have been informed by mathematical modelling. With the change in focus from elimination of the disease burden to elimination of Onchocerca volvulus, much remains to be done to refine, calibrate and validate existing models. Under the impetus of the NTD Modelling Consortium, the teams that developed EPIONCHO and ONCHOSIM have joined forces to compare and improve these frameworks to better assist ongoing elimination efforts. We review their current versions and describe how they are being used to address two key questions: (1) where can onchocerciasis be eliminated with current intervention strategies by 2020/2025? and (2) what alternative/complementary strategies could help to accelerate elimination where (1) cannot be achieved? The control and elimination of onchocerciasis from the African continent is at a crucial crossroad. The African Programme for Onchocerciasis Control closed at the end of 2015, and although a new platform for support and integration of NTD control has been launched, the disease will have to compete with a myriad of other national health priorities at a pivotal time in the road to elimination. However, never before had onchocerciasis control a better arsenal of intervention strategies as well as diagnostics. It is, therefore, timely to present two models of different geneses and modelling traditions as they come together to produce robust decision-support tools. We start by describing the structural and parametric assumptions of EPIONCHO and ONCHOSIM; we continue by summarizing the modelling of current treatment strategies with annual (or biannual) mass ivermectin distribution and introduce a number of alternative strategies, including other microfilaricidal therapies (such as moxidectin), macrofilaricidal (anti-wolbachial) treatments, focal vector control and the possibility of an onchocerciasis vaccine. We conclude by discussing challenges, opportunities and future directions. Copyright © 2016 Elsevier Ltd. All rights reserved.

ABS-FishCount: An Agent-Based Simulator of Underwater Sensors for Measuring the Amount of Fish.

PubMed

García-Magariño, Iván; Lacuesta, Raquel; Lloret, Jaime

2017-11-13

Underwater sensors provide one of the possibilities to explore oceans, seas, rivers, fish farms and dams, which all together cover most of our planet's area. Simulators can be helpful to test and discover some possible strategies before implementing these in real underwater sensors. This speeds up the development of research theories so that these can be implemented later. In this context, the current work presents an agent-based simulator for defining and testing strategies for measuring the amount of fish by means of underwater sensors. The current approach is illustrated with the definition and assessment of two strategies for measuring fish. One of these two corresponds to a simple control mechanism, while the other is an experimental strategy and includes an implicit coordination mechanism. The experimental strategy showed a statistically significant improvement over the control one in the reduction of errors with a large Cohen's d effect size of 2.55.

A new global strategy for the elimination of schistosomiasis.

PubMed

Ross, Allen G P; Chau, Thao N; Inobaya, Marianette T; Olveda, Remigio M; Li, Yuesheng; Harn, Donald A

2017-01-01

Mass drug administration utilising a single oral dose of 40mg/kg of praziquantel (PZQ) has been endorsed and advocated by the World Health Organisation (WHO) for the global control and elimination of schistosomiasis. However, this strategy is failing primarily because the drugs are not getting to the people who need them the most. The current global coverage is 20%, the drug compliance rate is less than 50%, and the drug efficacy is approximately 50%. Thus in reality, only about 5% of the reservoir human population is actually receiving intermittent chemotherapy. Despite claims that more of the drug will soon be made available the current strategy is inherently flawed and will not lead to disease elimination. We discuss the many practical issues related to this global strategy, and advocate for an integrated control strategy targeting the life cycle and the most at-risk. Moreover, we discuss how an integrated control package for schistosomiasis should fit within a larger integrated health package for rural and remote villages in the developing world. A holistic health system approach is required to achieve sustainable control and ultimately disease elimination. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Study of a control strategy for grid side converter in doubly- fed wind power system

NASA Astrophysics Data System (ADS)

Zhu, D. J.; Tan, Z. L.; Yuan, F.; Wang, Q. Y.; Ding, M.

2016-08-01

The grid side converter is an important part of the excitation system of doubly-fed asynchronous generator used in wind power system. As a three-phase voltage source PWM converter, it can not only transfer slip power in the form of active power, but also adjust the reactive power of the grid. This paper proposed a control approach for improving its performance. In this control approach, the dc voltage is regulated by a sliding mode variable structure control scheme and current by a variable structure controller based on the input output linearization. The theoretical bases of the sliding mode variable structure control were introduced, and the stability proof was presented. Switching function of the system has been deduced, sliding mode voltage controller model has been established, and the output of the outer voltage loop is the instruction of the inner current loop. Affine nonlinear model of two input two output equations on d-q axis for current has been established its meeting conditions of exact linearization were proved. In order to improve the anti-jamming capability of the system, a variable structure control was added in the current controller, the control law was deduced. The dual-loop control with sliding mode control in outer voltage loop and linearization variable structure control in inner current loop was proposed. Simulation results demonstrate the effectiveness of the proposed control strategy even during the dc reference voltage and system load variation.

Improved control strategy for PI-R current of DFIG considering voltage and current harmonics compensation

NASA Astrophysics Data System (ADS)

Song, S. Y.; Liu, Q. H.; Zhao, Y. N.; Liu, S. Y.

2016-08-01

With the rapid development of wind power generation, the related research of wind power control and integration issues has attracted much attention, and the focus of the research are shifting away from the ideal power grid environment to the actual power grid environment. As the main stream wind turbine generator, a doubly-fed induction generator (DFIG) is connected to the power grid directly by its stator, so it is particularly sensitive to the power grid. This paper studies the improvement of DFIG control technology in the power grid harmonic environment. Based on the DFIG dynamic model considering the power grid harmonic environment, this paper introduces the shortcomings of the common control strategy of DFIG, and puts forward the enhanced method. The decoupling control of the system is realized by compensating the coupling between the rotor harmonic voltage and harmonic current, improving the control performance. In addition, the simulation experiments on PSCAD/EMTDC are carried out to verify the correctness and effectiveness of the improved scheme.

Adaptive Insecure Attachment and Resource Control Strategies during Middle Childhood

ERIC Educational Resources Information Center

Chen, Bin-Bin; Chang, Lei

2012-01-01

By integrating the life history theory of attachment with resource control theory, the current study examines the hypothesis that insecure attachment styles reorganized in middle childhood are alternative adaptive strategies used to prepare for upcoming competition with the peer group. A sample of 654 children in the second through seventh grades…

Predictive control strategies for wind turbine system based on permanent magnet synchronous generator.

PubMed

Maaoui-Ben Hassine, Ikram; Naouar, Mohamed Wissem; Mrabet-Bellaaj, Najiba

2016-05-01

In this paper, Model Predictive Control and Dead-beat predictive control strategies are proposed for the control of a PMSG based wind energy system. The proposed MPC considers the model of the converter-based system to forecast the possible future behavior of the controlled variables. It allows selecting the voltage vector to be applied that leads to a minimum error by minimizing a predefined cost function. The main features of the MPC are low current THD and robustness against parameters variations. The Dead-beat predictive control is based on the system model to compute the optimum voltage vector that ensures zero-steady state error. The optimum voltage vector is then applied through Space Vector Modulation (SVM) technique. The main advantages of the Dead-beat predictive control are low current THD and constant switching frequency. The proposed control techniques are presented and detailed for the control of back-to-back converter in a wind turbine system based on PMSG. Simulation results (under Matlab-Simulink software environment tool) and experimental results (under developed prototyping platform) are presented in order to show the performances of the considered control strategies. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Optimal control of an invasive species using a reaction-diffusion model and linear programming

USGS Publications Warehouse

Bonneau, Mathieu; Johnson, Fred A.; Smith, Brian J.; Romagosa, Christina M.; Martin, Julien; Mazzotti, Frank J.

2017-01-01

Managing an invasive species is particularly challenging as little is generally known about the species’ biological characteristics in its new habitat. In practice, removal of individuals often starts before the species is studied to provide the information that will later improve control. Therefore, the locations and the amount of control have to be determined in the face of great uncertainty about the species characteristics and with a limited amount of resources. We propose framing spatial control as a linear programming optimization problem. This formulation, paired with a discrete reaction-diffusion model, permits calculation of an optimal control strategy that minimizes the remaining number of invaders for a fixed cost or that minimizes the control cost for containment or protecting specific areas from invasion. We propose computing the optimal strategy for a range of possible model parameters, representing current uncertainty on the possible invasion scenarios. Then, a best strategy can be identified depending on the risk attitude of the decision-maker. We use this framework to study the spatial control of the Argentine black and white tegus (Salvator merianae) in South Florida. There is uncertainty about tegu demography and we considered several combinations of model parameters, exhibiting various dynamics of invasion. For a fixed one-year budget, we show that the risk-averse strategy, which optimizes the worst-case scenario of tegus’ dynamics, and the risk-neutral strategy, which optimizes the expected scenario, both concentrated control close to the point of introduction. A risk-seeking strategy, which optimizes the best-case scenario, focuses more on models where eradication of the species in a cell is possible and consists of spreading control as much as possible. For the establishment of a containment area, assuming an exponential growth we show that with current control methods it might not be possible to implement such a strategy for some of the models that we considered. Including different possible models allows an examination of how the strategy is expected to perform in different scenarios. Then, a strategy that accounts for the risk attitude of the decision-maker can be designed.

How do Air Traffic Controllers Use Automation and Tools Differently During High Demand Situations?

NASA Technical Reports Server (NTRS)

Kraut, Joshua M.; Mercer, Joey; Morey, Susan; Homola, Jeffrey; Gomez, Ashley; Prevot, Thomas

2013-01-01

In a human-in-the-loop simulation, two air traffic controllers managed identical airspace while burdened with higher than average workload, and while using advanced tools and automation designed to assist with scheduling aircraft on multiple arrival flows to a single meter fix. This paper compares the strategies employed by each controller, and investigates how the controllers' strategies change while managing their airspace under more normal workload conditions and a higher workload condition. Each controller engaged in different methods of maneuvering aircraft to arrive on schedule, and adapted their strategies to cope with the increased workload in different ways. Based on the conclusions three suggestions are made: that quickly providing air traffic controllers with recommendations and information to assist with maneuvering and scheduling aircraft when burdened with increased workload will improve the air traffic controller's effectiveness, that the tools should adapt to the strategy currently employed by a controller, and that training should emphasize which traffic management strategies are most effective given specific airspace demands.

Transgenesis and paratransgenesis to control insect-borne diseases: Current status and future challenges

PubMed Central

Coutinho-Abreu, Iliano V.; Zhu, Kun Yan; Ramalho-Ortigao, Marcelo

2009-01-01

Insect-borne diseases cause significant human morbidity and mortality. Current control and preventive methods against vector-borne diseases rely mainly on insecticides. The emergence of insecticide resistance in many disease vectors highlights the necessity to develop new strategies to control these insects. Vector transgenesis and paratransgenesis are novel strategies that aim at reducing insect vectorial capacity, or seek to eliminate transmission of pathogens such as Plasmodium sp., Trypanosoma sp., and Dengue virus currently being developed. Vector transgenesis relies on direct genetic manipulation of disease vectors making them incapable of functioning as vectors of a given pathogen. Paratransgenesis focuses on utilizing genetically modified insect symbionts to express molecules within the vector that are deleterious to pathogens they transmit. Despite the many successes achieved in developing such techniques in the last several years, many significant barriers remain and need to be overcome prior to any of these approaches become a reality. Here, we highlight the current status of these strategies, pointing out advantages and constraints, and also explore issues that need to be resolved before the establishment of transgenesis and paratransgenesis as tools to prevent vector-borne diseases. PMID:19819346

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

Optimal design strategy of switching converters employing current injected control

NASA Astrophysics Data System (ADS)

Lee, F. C.; Fang, Z. D.; Lee, T. H.

1985-01-01

This paper analyzes a buck/boost regulator employing current-injected control (CIC). It reveals the complex interactions between the dc loop and the current-injected loop and underlines the fundamental principle that governs the loop gain determination. Three commonly used compensation techniques are compared. The integral and lead/lag compensation are shown to be most desirable for performance optimization and stability.

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.

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

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.

Strategy difficulty effects in young and older adults' episodic memory are modulated by inter-stimulus intervals and executive control processes.

PubMed

Burger, Lucile; Uittenhove, Kim; Lemaire, Patrick; Taconnat, Laurence

2017-04-01

Efficient execution of strategies is crucial to memory performance and to age-related differences in this performance. Relative strategy complexity influences memory performance and aging effects on memory. Here, we aimed to further our understanding of the effects of relative strategy complexity by looking at the role of cognitive control functions and the time-course of the effects of relative strategy complexity. Thus, we manipulated inter-stimulus intervals (ISI) and assessed executive functions. Results showed that (a) performance as a function of the relative strategy difficulty of the current and previous trial was modulated by ISI, (b) these effects were modulated by inhibition capacities, and (c) significant age differences were found in the way ISI modulates relative strategy difficulty. These findings have important implications for understanding the relationships between aging, executive control, and strategy execution in episodic memory. Copyright © 2017 Elsevier B.V. All rights reserved.

Investigation of load current feed-forward control strategy for wind power grid connected inverter through VSC-HVDC

NASA Astrophysics Data System (ADS)

Liu, Hongbo; Liu, Haihan; Liu, Sitong; Peng, Huanhuan

2018-06-01

The VSC-HVDC connection system will be the effective transmission method for the large scale and long distance integrated wind farm. Because of the fluctuating power, the DC voltage will be over-voltage or under-voltage in transmission line which will affect the steady operation of the wind power integrating system. In order to mitigate the DC voltage variation of the grid-connected inverter on the grid side and improve the dynamic response of the system, a load current feed-forward control scheme is put forward. Firstly, this paper analyses stability of a system without additional feed-forward control based on double close loop. Secondly, the load current which can indicate the power changes is introduced to counteract the fluctuation of DC voltage in the improvement control scheme. By simulating the results show that the proposed control strategy can improve the dynamic response performance and mitigate the fluctuation of the active power output of the wind farm.

Driver electronics design and control for a total artificial heart linear motor.

PubMed

Unthan, Kristin; Cuenca-Navalon, Elena; Pelletier, Benedikt; Finocchiaro, Thomas; Steinseifer, Ulrich

2018-01-27

For any implantable device size and efficiency are critical properties. Thus, a linear motor for a Total Artificial Heart was optimized with focus on driver electronics and control strategies. Hardware requirements were defined from power supply and motor setup. Four full bridges were chosen for the power electronics. Shunt resistors were set up for current measurement. Unipolar and bipolar switching for power electronics control were compared regarding current ripple and power losses. Here, unipolar switching showed smaller current ripple and required less power to create the necessary motor forces. Based on calculations for minimal power losses Lorentz force was distributed to the actor's four coils. The distribution was determined as ratio of effective magnetic flux through each coil, which was captured by a force test rig. Static and dynamic measurements under physiological conditions analyzed interaction of control and hardware and all efficiencies were over 89%. In conclusion, the designed electronics, optimized control strategy and applied current distribution create the required motor force and perform optimal under physiological conditions. The developed driver electronics and control offer optimized size and efficiency for any implantable or portable device with multiple independent motor coils. Graphical Abstract ᅟ.

Rethinking volitional control over task choice in multitask environments: use of a stimulus set selection strategy in voluntary task switching.

PubMed

Arrington, Catherine M; Weaver, Starla M

2015-01-01

Under conditions of volitional control in multitask environments, subjects may engage in a variety of strategies to guide task selection. The current research examines whether subjects may sometimes use a top-down control strategy of selecting a task-irrelevant stimulus dimension, such as location, to guide task selection. We term this approach a stimulus set selection strategy. Using a voluntary task switching procedure, subjects voluntarily switched between categorizing letter and number stimuli that appeared in two, four, or eight possible target locations. Effects of stimulus availability, manipulated by varying the stimulus onset asynchrony between the two target stimuli, and location repetition were analysed to assess the use of a stimulus set selection strategy. Considered across position condition, Experiment 1 showed effects of both stimulus availability and location repetition on task choice suggesting that only in the 2-position condition, where selection based on location always results in a target at the selected location, subjects may have been using a stimulus set selection strategy on some trials. Experiment 2 replicated and extended these findings in a visually more cluttered environment. These results indicate that, contrary to current models of task selection in voluntary task switching, the top-down control of task selection may occur in the absence of the formation of an intention to perform a particular task.

News focus: Report on state and local air toxics regulatory strategies published by STAPPA/ALAPCO (State and Territorial Air Pollution Program Administrators/Association of Local Air Pollution Control Officials)

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

Not Available

1989-12-01

The report is entitled Toxic Air Pollutants: State and Local Regulatory Strategies - 1989. The 364-page report is the result of a survey of state and local air pollution control agencies, which solicited information on their programs to control air toxics. According to the survey, every state currently has a program to address emissions of air toxics. Additionally, 27 of the 40 local agencies that responded to the survey have, or are developing, air toxics programs. The strategies employed by state and local agencies vary widely, including control technology requirements, risk assessment, acceptable ambient guidelines, or a combination of thesemore » approaches. This is a report summarizing the air toxics control programs currently implemented (or under development) by state and local air pollution control agencies throughout the US. The report is based upon a survey of all 50 states and 220 local air pollution control agencies conducted by the State and Territorial Air Pollution Program Administrators (STAPPA) and the Association of Local Air Pollution Control Officials (ALAPCO). This survey updates one published five years earlier.« less

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.

Elicitors as alternative strategy to pesticides in grapevine? Current knowledge on their mode of action from controlled conditions to vineyard.

PubMed

Delaunois, Bertrand; Farace, Giovanni; Jeandet, Philippe; Clément, Christophe; Baillieul, Fabienne; Dorey, Stéphan; Cordelier, Sylvain

2014-04-01

Development and optimisation of alternative strategies to reduce the use of classic chemical inputs for protection against diseases in vineyard is becoming a necessity. Among these strategies, one of the most promising consists in the stimulation and/or potentiation of the grapevine defence responses by the means of elicitors. Elicitors are highly diverse molecules both in nature and origins. This review aims at providing an overview of the current knowledge on these molecules and will highlight their potential efficacy from the laboratory in controlled conditions to vineyards. Recent findings and concepts (especially on plant innate immunity) and the new terminology (microbe-associated molecular patterns, effectors, etc.) are also discussed in this context. Other objectives of this review are to highlight the difficulty of transferring elicitors use and results from the controlled conditions to the vineyard, to determine their practical and effective use in viticulture and to propose ideas for improving their efficacy in non-controlled conditions.

Long-term effectiveness of the integrated schistosomiasis control strategy with emphasis on infectious source control in China: a 10-year evaluation from 2005 to 2014.

PubMed

Wang, Xiaoli; Wang, Wei; Wang, Peng

2017-02-01

Schistosomiasis is a neglected tropical parasitic disease of great public health significance worldwide. Currently, mass drug administration with praziquantel remains the major strategy for global schistosomiasis control programs. Since 2005, an integrated strategy with emphasis on infectious source control was implemented for the control of schistosomiasis japonica, a major public health concern in China, and pilot studies have demonstrated that such a strategy is effective to reduce the prevalence of Schistosoma japonicum infection in both humans and bovines. However, there is little knowledge on the long-term effectiveness of this integrated strategy for controlling schistosomiasis japonica. The aim of this study was to evaluate the long-term effectiveness of the integrated strategy for schistosomiasis control following the 10-year implementation, based on the data from the national schistosomiasis control program released by the Ministry of Health, People's Republic of China. In 2014, there were 5 counties in which the transmission of schistosomiasis japonica had not been interrupted, which reduced by 95.2% as compared to that in 2005 (105 counties). The number of schistosomiasis patients and acute cases reduced by 85.5 and 99.7% in 2014 (115,614 cases and 2 cases) as compared to that in 2005 (798,762 cases and 564 cases), and the number of bovines and S. japonicum-infected bovines reduced by 47.9 and 98% in 2014 (919,579 bovines and 666 infected bovines) as compared to that in 2005 (1,764,472 bovines and 33,736 infected bovines), respectively. During the 10-year implementation of the integrated strategy, however, there was a minor fluctuation in the area of Oncomelania hupensis snail habitats, and there was only a 5.6% reduction in the area of snail habitats in 2014 relative to in 2005. The results of the current study demonstrate that the 10-year implementation of the integrated strategy with emphasis on infectious source has greatly reduced schistosomiasis-related morbidity in humans and bovines. It is concluded that the new integrated strategy has remarkable long-term effectiveness on the transmission of schistosomiasis japonica in China, which facilitates the shift of the national schistosomiasis control program from transmission control to transmission interruption and elimination. However, such a strategy seems to have little effect on the shrinking of areas of snail habitats.

Counterproliferation strategy: The influence of technology, budget, and arms control on theater missile defenses. Strategic research project

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

Parlier, G.H.

1996-05-20

This paper describes the historical evolution of the theater missile threat during World War II and the Persian Gulf War, and analyzes current technological challenges, budgetary pressures, and arms control restraints which constrain the development and deployment of effective theater missile defenses. The impact of these trends on strategic concepts as outlined in the National Military Strategy and their implications for attaining national policy objectives is assessed. A systems approach is used to described analyze, and evaluate the effectiveness of emerging counterproliferation strategy within the framework of an ends-ways-means strategy formulation paradigm. I conclude that current trends will lead tomore » a self-deterring strategy: resources are inadequate to support the ways we intend to achieve our national objectives. Recommendations are made to eliminate unacceptable risk and enhance the concept of `extended conventional deterrence` consistent with U.S. national values and security interests for our role in a new world order.« less

ABS-FishCount: An Agent-Based Simulator of Underwater Sensors for Measuring the Amount of Fish

PubMed Central

2017-01-01

Underwater sensors provide one of the possibilities to explore oceans, seas, rivers, fish farms and dams, which all together cover most of our planet’s area. Simulators can be helpful to test and discover some possible strategies before implementing these in real underwater sensors. This speeds up the development of research theories so that these can be implemented later. In this context, the current work presents an agent-based simulator for defining and testing strategies for measuring the amount of fish by means of underwater sensors. The current approach is illustrated with the definition and assessment of two strategies for measuring fish. One of these two corresponds to a simple control mechanism, while the other is an experimental strategy and includes an implicit coordination mechanism. The experimental strategy showed a statistically significant improvement over the control one in the reduction of errors with a large Cohen’s d effect size of 2.55. PMID:29137165

Intelligent voltage control strategy for three-phase UPS inverters with output LC filter

NASA Astrophysics Data System (ADS)

Jung, J. W.; Leu, V. Q.; Dang, D. Q.; Do, T. D.; Mwasilu, F.; Choi, H. H.

2015-08-01

This paper presents a supervisory fuzzy neural network control (SFNNC) method for a three-phase inverter of uninterruptible power supplies (UPSs). The proposed voltage controller is comprised of a fuzzy neural network control (FNNC) term and a supervisory control term. The FNNC term is deliberately employed to estimate the uncertain terms, and the supervisory control term is designed based on the sliding mode technique to stabilise the system dynamic errors. To improve the learning capability, the FNNC term incorporates an online parameter training methodology, using the gradient descent method and Lyapunov stability theory. Besides, a linear load current observer that estimates the load currents is used to exclude the load current sensors. The proposed SFNN controller and the observer are robust to the filter inductance variations, and their stability analyses are described in detail. The experimental results obtained on a prototype UPS test bed with a TMS320F28335 DSP are presented to validate the feasibility of the proposed scheme. Verification results demonstrate that the proposed control strategy can achieve smaller steady-state error and lower total harmonic distortion when subjected to nonlinear or unbalanced loads compared to the conventional sliding mode control method.

Optimal management of non-Markovian biological populations

USGS Publications Warehouse

Williams, B.K.

2007-01-01

Wildlife populations typically are described by Markovian models, with population dynamics influenced at each point in time by current but not previous population levels. Considerable work has been done on identifying optimal management strategies under the Markovian assumption. In this paper we generalize this work to non-Markovian systems, for which population responses to management are influenced by lagged as well as current status and/or controls. We use the maximum principle of optimal control theory to derive conditions for the optimal management such a system, and illustrate the effects of lags on the structure of optimal habitat strategies for a predator-prey system.

Sustainable improvement of animal health care by systematic quality risk management according to the HACCP concept.

PubMed

Noordhuizen, J P; Welpelo, H J

1996-12-01

This paper addresses the principles of the Hazard Analysis Critical Control Point (HACCP) concept as applied to animal health management strategy. Characteristics of the concept were analysed and compared with those of current animal health care strategies for disease risk identification and herd health management, insurance, and certification. HACCP is a hybrid strategy of quality control at both production process and product level. Animal health is considered a particular quality feature. We show that process control (expressed in terms of controlling both general and specific disease risk factors) and product control (expressed in terms of testing animals or animal products for specific disease agents) could form the basis for improving animal health. We conclude that HACCP provides ample opportunity for preventive health action and risk management at a relatively low cost in terms of labour, finance and documentation expenditure, at both the farm and sector level. Epidemiological field studies are currently needed to identify critical control points and to design HACCP procedures for livestock producers. In the long run, HACCP based animal health care can be further developed into a quality control systems approach to cover all aspects that are related, either directly or indirectly, to animal health.

Innovations in prosthetic interfaces for the upper extremity.

PubMed

Kung, Theodore A; Bueno, Reuben A; Alkhalefah, Ghadah K; Langhals, Nicholas B; Urbanchek, Melanie G; Cederna, Paul S

2013-12-01

Advancements in modern robotic technology have led to the development of highly sophisticated upper extremity prosthetic limbs. High-fidelity volitional control of these devices is dependent on the critical interface between the patient and the mechanical prosthesis. Recent innovations in prosthetic interfaces have focused on several control strategies. Targeted muscle reinnervation is currently the most immediately applicable prosthetic control strategy and is particularly indicated in proximal upper extremity amputations. Investigation into various brain interfaces has allowed acquisition of neuroelectric signals directly or indirectly from the central nervous system for prosthetic control. Peripheral nerve interfaces permit signal transduction from both motor and sensory nerves with a higher degree of selectivity. This article reviews the current developments in each of these interface systems and discusses the potential of these approaches to facilitate motor control and sensory feedback in upper extremity neuroprosthetic devices.

Current trends in mass spectrometry of peptides and proteins: Application to veterinary and sports-doping control.

PubMed

van den Broek, Irene; Blokland, Marco; Nessen, Merel A; Sterk, Saskia

2015-01-01

Detection of misuse of peptides and proteins as growth promoters is a major issue for sport and food regulatory agencies. The limitations of current analytical detection strategies for this class of compounds, in combination with their efficacy in growth-promoting effects, make peptide and protein drugs highly susceptible to abuse by either athletes or farmers who seek for products to illicitly enhance muscle growth. Mass spectrometry (MS) for qualitative analysis of peptides and proteins is well-established, particularly due to tremendous efforts in the proteomics community. Similarly, due to advancements in targeted proteomic strategies and the rapid growth of protein-based biopharmaceuticals, MS for quantitative analysis of peptides and proteins is becoming more widely accepted. These continuous advances in MS instrumentation and MS-based methodologies offer enormous opportunities for detection and confirmation of peptides and proteins. Therefore, MS seems to be the method of choice to improve the qualitative and quantitative analysis of peptide and proteins with growth-promoting properties. This review aims to address the opportunities of MS for peptide and protein analysis in veterinary control and sports-doping control with a particular focus on detection of illicit growth promotion. An overview of potential peptide and protein targets, including their amino acid sequence characteristics and current MS-based detection strategies is, therefore, provided. Furthermore, improvements of current and new detection strategies with state-of-the-art MS instrumentation are discussed for qualitative and quantitative approaches. © 2013 Wiley Periodicals, Inc.

A control strategy for grid-side converter of DFIG under unbalanced condition based on Dig SILENT/Power Factory

NASA Astrophysics Data System (ADS)

Han, Pingping; Zhang, Haitian; Chen, Lingqi; Zhang, Xiaoan

2018-01-01

The models of doubly fed induction generator (DFIG) and its grid-side converter (GSC) are established under unbalanced grid condition based on DIgSILENT/PowerFactory. According to the mathematical model, the vector equations of positive and negative sequence voltage and current are deduced in the positive sequence synchronous rotating reference frame d-q-0 when the characteristics of the simulation software are considered adequately. Moreover, the reference value of current component of GSC in the positive sequence frame d-q-0 under unbalanced condition can be obtained to improve the traditional control of GSC when the national issue of unbalanced current limits is combined. The simulated results indicate that the control strategy can restrain negative sequence current and the two times frequency power wave of GSC’s ac side effectively. The voltage of DC bus can be maintained a constant to ensure the uninterrupted operation of DFIG under unbalanced grid condition eventually.

An Examination of Strategy Implementation During Abstract Nonlinguistic Category Learning in Aphasia.

PubMed

Vallila-Rohter, Sofia; Kiran, Swathi

2015-08-01

Our purpose was to study strategy use during nonlinguistic category learning in aphasia. Twelve control participants without aphasia and 53 participants with aphasia (PWA) completed a computerized feedback-based category learning task consisting of training and testing phases. Accuracy rates of categorization in testing phases were calculated. To evaluate strategy use, strategy analyses were conducted over training and testing phases. Participant data were compared with model data that simulated complex multi-cue, single feature, and random pattern strategies. Learning success and strategy use were evaluated within the context of standardized cognitive-linguistic assessments. Categorization accuracy was higher among control participants than among PWA. The majority of control participants implemented suboptimal or optimal multi-cue and single-feature strategies by testing phases of the experiment. In contrast, a large subgroup of PWA implemented random patterns, or no strategy, during both training and testing phases of the experiment. Person-to-person variability arises not only in category learning ability but also in the strategies implemented to complete category learning tasks. PWA less frequently developed effective strategies during category learning tasks than control participants. Certain PWA may have impairments of strategy development or feedback processing not captured by language and currently probed cognitive abilities.

H2/H∞ control for grid-feeding converter considering system uncertainty

NASA Astrophysics Data System (ADS)

Li, Zhongwen; Zang, Chuanzhi; Zeng, Peng; Yu, Haibin; Li, Shuhui; Fu, Xingang

2017-05-01

Three-phase grid-feeding converters are key components to integrate distributed generation and renewable power sources to the power utility. Conventionally, proportional integral and proportional resonant-based control strategies are applied to control the output power or current of a GFC. But, those control strategies have poor transient performance and are not robust against uncertainties and volatilities in the system. This paper proposes a H2/H∞-based control strategy, which can mitigate the above restrictions. The uncertainty and disturbance are included to formulate the GFC system state-space model, making it more accurate to reflect the practical system conditions. The paper uses a convex optimisation method to design the H2/H∞-based optimal controller. Instead of using a guess-and-check method, the paper uses particle swarm optimisation to search a H2/H∞ optimal controller. Several case studies implemented by both simulation and experiment can verify the superiority of the proposed control strategy than the traditional PI control methods especially under dynamic and variable system conditions.

Suspension force control of bearingless permanent magnet slice motor based on flux linkage identification.

PubMed

Zhu, Suming; Zhu, Huangqiu

2015-07-01

The control accuracy and dynamic performance of suspension force are confined in the traditional bearingless permanent magnet slice motor (BPMSM) control strategies because the suspension force control is indirectly achieved by adopting a closed loop of displacement only. Besides, the phase information in suspension force control relies on accurate measurement of rotor position, making the control system more complex. In this paper, a new suspension force control strategy with displacement and radial suspension force double closed loops is proposed, the flux linkage of motor windings is identified based on voltage-current model and the flexibility of motor control can be improved greatly. Simulation and experimental results show that the proposed suspension force control strategy is effective to realize the stable operation of the BPMSM. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Design and application of electromechanical actuators for deep space missions

NASA Technical Reports Server (NTRS)

Haskew, Tim A.; Wander, John

1993-01-01

The annual report Design and Application of Electromechanical Actuators for Deep Space Missions is presented. The reporting period is 16 Aug. 1992 to 15 Aug. 1993. However, the primary focus will be work performed since submission of our semi-annual progress report in Feb. 1993. Substantial progress was made. We currently feel confident in providing guidelines for motor and control strategy selection in electromechanical actuators to be used in thrust vector control (TVC) applications. A small portion was presented in the semi-annual report. At this point, we have implemented highly detailed simulations of various motor/drive systems. The primary motor candidates were the brushless dc machine, permanent magnet synchronous machine, and the induction machine. The primary control implementations were pulse width modulation and hysteresis current control. Each of the two control strategies were applied to each of the three motor choices. With either pulse width modulation or hysteresis current control, the induction machine was always vector controlled. A standard test position command sequence for system performance evaluation is defined. Currently, we are gathering all of the necessary data for formal presentation of the results. Briefly stated for TVC application, we feel that the brushless dc machine operating under PWM current control is the best option. Substantial details on the topic, with supporting simulation results, will be provided later, in the form of a technical paper prepared for submission and also in the next progress report with more detail than allowed for paper publication.

Systems and methods for providing power to a load based upon a control strategy

DOEpatents

Perisic, Milun; Kajouke, Lateef A; Ransom, Ray M

2013-12-24

Systems and methods are provided for an electrical system. The electrical system includes a load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage from the voltage source through the interface and to provide a voltage and current to the load. Wherein, when the controller is in a constant voltage mode, the controller provides a constant voltage to the load, when the controller is in a constant current mode, the controller provides a constant current to the load, and when the controller is in a constant power mode, the controller provides a constant power to the load.

Public authority control strategy for opinion evolution in social networks

NASA Astrophysics Data System (ADS)

Chen, Xi; Xiong, Xi; Zhang, Minghong; Li, Wei

2016-08-01

This paper addresses the need to deal with and control public opinion and rumors. Existing strategies to control public opinion include degree, random, and adaptive bridge control strategies. In this paper, we use the HK model to present a public opinion control strategy based on public authority (PA). This means utilizing the influence of expert or high authority individuals whose opinions we control to obtain the optimum effect in the shortest time possible and thus reach a consensus of public opinion. Public authority (PA) is only influenced by individuals' attributes (age, economic status, and education level) and not their degree distribution; hence, in this paper, we assume that PA complies with two types of public authority distribution (normal and power-law). According to the proposed control strategy, our experiment is based on random, degree, and public authority control strategies in three different social networks (small-world, scale-free, and random) and we compare and analyze the strategies in terms of convergence time (T), final number of controlled agents (C), and comprehensive efficiency (E). We find that different network topologies and the distribution of the PA in the network can influence the final controlling effect. While the effect of PA strategy differs in different network topology structures, all structures achieve comprehensive efficiency with any kind of public authority distribution in any network. Our findings are consistent with several current sociological phenomena and show that in the process of public opinion/rumor control, considerable attention should be paid to high authority individuals.

Public authority control strategy for opinion evolution in social networks.

PubMed

Chen, Xi; Xiong, Xi; Zhang, Minghong; Li, Wei

2016-08-01

This paper addresses the need to deal with and control public opinion and rumors. Existing strategies to control public opinion include degree, random, and adaptive bridge control strategies. In this paper, we use the HK model to present a public opinion control strategy based on public authority (PA). This means utilizing the influence of expert or high authority individuals whose opinions we control to obtain the optimum effect in the shortest time possible and thus reach a consensus of public opinion. Public authority (PA) is only influenced by individuals' attributes (age, economic status, and education level) and not their degree distribution; hence, in this paper, we assume that PA complies with two types of public authority distribution (normal and power-law). According to the proposed control strategy, our experiment is based on random, degree, and public authority control strategies in three different social networks (small-world, scale-free, and random) and we compare and analyze the strategies in terms of convergence time (T), final number of controlled agents (C), and comprehensive efficiency (E). We find that different network topologies and the distribution of the PA in the network can influence the final controlling effect. While the effect of PA strategy differs in different network topology structures, all structures achieve comprehensive efficiency with any kind of public authority distribution in any network. Our findings are consistent with several current sociological phenomena and show that in the process of public opinion/rumor control, considerable attention should be paid to high authority individuals.

Extremity War Injuries: Current Management and Research Priorities

DTIC Science & Technology

2012-01-01

sal- vage and amputation. The 13 articles generated from this symposium ad- dress these topics as well as multi- modal strategies for pain control...reconstruction, and reha- bilitation. The last seven articles of this supplement address lessons learned, outcomes measures, current strategies, and knowledge... bioburden , which has resulted in im- proved patient care. At the EWI VII Symposium, sev- eral research priorities were outlined in the areas of acute care

Old Disease and New Challenges: Major Obstacles of Current Strategies in the Prevention of Pertussis

PubMed Central

Sedighi, Iraj; Karimi, Abdollah; Amanati, Ali

2016-01-01

Context Universal immunization against Bordetella pertussis has partially controlled the burden of the disease and its transmission. However, according to recent data, the epidemiology of this vaccine-preventable disease has changed. Now, younger infants, adolescents, and adults are at greater risk of infection. This article has studied the interaction between the various factors involved in the changing epidemiology of pertussis and the major obstacles faced by the current strategies in its prevention. Evidence Acquisition In this narrative review, the most recently published sources of information on pertussis control measures, consisting of textbooks and articles, have been reviewed. We focused on the more recent data about the changing epidemiology or pertussis in Scopus through the use of the MeSH-term words [pertussis] or [whooping cough] and [epidemiology] or [outbreak] or [resurgence], but our search was not restricted to this particular strategy; we also tried to find all of the most recent available data in the general field through other means. Results Primary and booster doses of the pertussis vaccine seem to partially control transmission of the disease, but despite the different preventive strategies available, pertussis continues to cause mortality and morbidity among high-risk groups. Conclusions Adding booster doses of acellular pertussis vaccine to the current national immunization practices with whole-cell vaccines for young adults and pregnant women seems to be a good option for controlling mortality and morbidity among high-risk groups such as very young infants. PMID:27729960

Dynamic performance analysis of permanent magnet contactor with a flux-weakening control strategy

NASA Astrophysics Data System (ADS)

Wang, Xianbing; Lin, Heyun; Fang, Shuhua; Jin, Ping; Wang, Junhua; Ho, S. L.

2011-04-01

A new flux-weakening control strategy for permanent magnet contactors is proposed. By matching the dynamic attraction force and the antiforce, the terminal velocity and collision energy of the movable iron in the closing process are significantly reduced. The movable iron displacement is estimated by detecting the closing voltage and current with the proposed control. A dynamic mathematical model is also established under four kinds of excitation scenarios. The attraction force and flux linkage are predicted by finite element method and the dynamics of the closing process is simulated using the 4th-order Runge-Kutta algorithm. Experiments are carried out on a 250A prototype with an intelligent control unit to verify the proposed control strategy.

Evaluating non-detection risk associated with metabarcoding approaches for rare metabarcoding approaches

EPA Science Inventory

Early detection of non-indigenous species (NIS), newly introduced species at low abundance in the monitoring area, can strengthen current management strategies including NIS control and eradication. A practical early detection strategy requires achieving balance between efficient...

Long-term impact of the World Bank Loan Project for schistosomiasis control: a comparison of the spatial distribution of schistosomiasis risk in China.

PubMed

Zhang, Zhijie; Zhu, Rong; Ward, Michael P; Xu, Wanghong; Zhang, Lijuan; Guo, Jiagang; Zhao, Fei; Jiang, Qingwu

2012-01-01

The World Bank Loan Project (WBLP) for controlling schistosomiasis in China was implemented during 1992-2001. Its short-term impact has been assessed from non-spatial perspective, but its long-term impact remains unclear and a spatial evaluation has not previously been conducted. Here we compared the spatial distribution of schistosomiasis risk using national datasets in the lake and marshland regions from 1999-2001 and 2007-2008 to evaluate the long-term impact of WBLP strategy on China's schistosomiasis burden. A hierarchical Poisson regression model was developed in a Bayesian framework with spatially correlated and uncorrelated heterogeneities at the county-level, modeled using a conditional autoregressive prior structure and a spatially unstructured Gaussian distribution, respectively. There were two important findings from this study. The WBLP strategy was found to have a good short-term impact on schistosomiasis control, but its long-term impact was not ideal. It has successfully reduced the morbidity of schistosomiasis to a low level, but can not contribute further to China's schistosomiasis control because of the current low endemic level. A second finding is that the WBLP strategy could not effectively compress the spatial distribution of schistosomiasis risk. To achieve further reductions in schistosomiasis-affected areas, and for sustainable control, focusing on the intermediate host snail should become the next step to interrupt schistosomiasis transmission within the two most affected regions surrounding the Dongting and Poyang Lakes. Furthermore, in the lower reaches of the Yangtze River, the WBLP's morbidity control strategy may need to continue for some time until snails in the upriver provinces have been well controlled. It is difficult to further reduce morbidity due to schistosomiasis using a chemotherapy-based control strategy in the lake and marshland regions of China because of the current low endemic levels of infection. The future control strategy for schistosomiasis should instead focus on a snail-based integrated control strategy to maintain the program achievements and sustainably reduce the burden of schistosomiasis in China.

Assessment of research and development (R and D) needs in LPG safety and environmental control

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

DeSteese, J.G.

1982-05-01

The report characterizes the LPG industry covering all operations from production to end use, reviews current knowledge of LPG release phenomenology, summarizes the status of current LPG release prevention and control methodology, and identifies any remaining safety and environmental problems and recommends R and D strategies that may mitigate these problems. (ACR)

MTPA control of mechanical sensorless IPMSM based on adaptive nonlinear control.

PubMed

Najjar-Khodabakhsh, Abbas; Soltani, Jafar

2016-03-01

In this paper, an adaptive nonlinear control scheme has been proposed for implementing maximum torque per ampere (MTPA) control strategy corresponding to interior permanent magnet synchronous motor (IPMSM) drive. This control scheme is developed in the rotor d-q axis reference frame using adaptive input-output state feedback linearization (AIOFL) method. The drive system control stability is supported by Lyapunov theory. The motor inductances are online estimated by an estimation law obtained by AIOFL. The estimation errors of these parameters are proved to be asymptotically converged to zero. Based on minimizing the motor current amplitude, the MTPA control strategy is performed by using the nonlinear optimization technique while considering the online reference torque. The motor reference torque is generated by a conventional rotor speed PI controller. By performing MTPA control strategy, the generated online motor d-q reference currents were used in AIOFL controller to obtain the SV-PWM reference voltages and the online estimation of the motor d-q inductances. In addition, the stator resistance is online estimated using a conventional PI controller. Moreover, the rotor position is detected using the online estimation of the stator flux and online estimation of the motor q-axis inductance. Simulation and experimental results obtained prove the effectiveness and the capability of the proposed control method. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

Systematic Training Program for Enhancing Learning Strategies and Skills: Further Development. Interim Report for Period March 1976-March 1977.

ERIC Educational Resources Information Center

Dansereau, Donald F.; And Others

The purpose of this current research effort was to identify and validate the effectiveness of alternative learning strategies. Learners employing networking and interactive peer study substrategies achieved more than did no-treatment controls. Similarly, strategies-trained learners reported greater positive learning attitude changes than did…

Alcohol Consumption and Negative Sex-Related Consequences among College Women: The Moderating Role of Alcohol Protective Behavioral Strategies

ERIC Educational Resources Information Center

Moorer, Kayla D.; Madson, Michael B.; Mohn, Richard S.; Nicholson, Bonnie C.

2013-01-01

Alcohol protective behavioral strategies (PBS) limit overall negative consequences; however, less is known about the relationship between PBS and negative sex-related consequences. The purpose of the current study was to examine the moderating effects of 2 distinct types of PBS--controlled consumption strategies and serious harm reduction…

Analysis of decentralized variable structure control for collective search by mobile robots

NASA Astrophysics Data System (ADS)

Goldsmith, Steven Y.; Feddema, John T.; Robinett, Rush D., III

1998-10-01

This paper presents an analysis of a decentralized coordination strategy for organizing and controlling a team of mobile robots performing collective search. The alpha- beta coordination strategy is a family of collective search algorithms that allow teams of communicating robots to implicitly coordinate their search activities through a division of labor based on self-selected roles. In an alpha- beta team, alpha agents are motivated to improve their status by exploring new regions of the search space. Beta agents are conservative, and rely on the alpha agents to provide advanced information on favorable regions of the search space. An agent selects its current role dynamically based on its current status value relative to the current status values of the other team members. Status is determined by some function of the agent's sensor readings, and is generally a measurement of source intensity at the agent's current location. Variations on the decision rules determining alpha and beta behavior produce different versions of the algorithm that lead to different global properties. The alpha-beta strategy is based on a simple finite-state machine that implements a form of Variable Structure Control (VSC). The VSC system changes the dynamics of the collective system by abruptly switching at defined states to alternative control laws. In VSC, Lyapunov's direct method is often used to design control surfaces which guide the system to a given goal. We introduce the alpha- beta algorithm and present an analysis of the equilibrium point and the global stability of the alpha-beta algorithm based on Lyapunov's method.

Data analytics and optimization of an ice-based energy storage system for commercial buildings

DOE PAGES

Luo, Na; Hong, Tianzhen; Li, Hui; ...

2017-07-25

Ice-based thermal energy storage (TES) systems can shift peak cooling demand and reduce operational energy costs (with time-of-use rates) in commercial buildings. The accurate prediction of the cooling load, and the optimal control strategy for managing the charging and discharging of a TES system, are two critical elements to improving system performance and achieving energy cost savings. This study utilizes data-driven analytics and modeling to holistically understand the operation of an ice–based TES system in a shopping mall, calculating the system’s performance using actual measured data from installed meters and sensors. Results show that there is significant savings potential whenmore » the current operating strategy is improved by appropriately scheduling the operation of each piece of equipment of the TES system, as well as by determining the amount of charging and discharging for each day. A novel optimal control strategy, determined by an optimization algorithm of Sequential Quadratic Programming, was developed to minimize the TES system’s operating costs. Three heuristic strategies were also investigated for comparison with our proposed strategy, and the results demonstrate the superiority of our method to the heuristic strategies in terms of total energy cost savings. Specifically, the optimal strategy yields energy costs of up to 11.3% per day and 9.3% per month compared with current operational strategies. A one-day-ahead hourly load prediction was also developed using machine learning algorithms, which facilitates the adoption of the developed data analytics and optimization of the control strategy in a real TES system operation.« less

Data analytics and optimization of an ice-based energy storage system for commercial buildings

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

Luo, Na; Hong, Tianzhen; Li, Hui

Ice-based thermal energy storage (TES) systems can shift peak cooling demand and reduce operational energy costs (with time-of-use rates) in commercial buildings. The accurate prediction of the cooling load, and the optimal control strategy for managing the charging and discharging of a TES system, are two critical elements to improving system performance and achieving energy cost savings. This study utilizes data-driven analytics and modeling to holistically understand the operation of an ice–based TES system in a shopping mall, calculating the system’s performance using actual measured data from installed meters and sensors. Results show that there is significant savings potential whenmore » the current operating strategy is improved by appropriately scheduling the operation of each piece of equipment of the TES system, as well as by determining the amount of charging and discharging for each day. A novel optimal control strategy, determined by an optimization algorithm of Sequential Quadratic Programming, was developed to minimize the TES system’s operating costs. Three heuristic strategies were also investigated for comparison with our proposed strategy, and the results demonstrate the superiority of our method to the heuristic strategies in terms of total energy cost savings. Specifically, the optimal strategy yields energy costs of up to 11.3% per day and 9.3% per month compared with current operational strategies. A one-day-ahead hourly load prediction was also developed using machine learning algorithms, which facilitates the adoption of the developed data analytics and optimization of the control strategy in a real TES system operation.« less

Back to the future: Rethinking global control of tuberculosis.

PubMed

Bloom, Barry R; Atun, Rifat

2016-03-09

If the ultimate goal of controlling an infectious disease is to interrupt transmission, the current global tuberculosis strategy is not succeeding. Copyright © 2016, American Association for the Advancement of Science.

Control and management of congenital Chagas disease in Europe and other non-endemic countries: current policies and practices.

PubMed

Soriano-Arandes, Antoni; Angheben, Andrea; Serre-Delcor, Nuria; Treviño-Maruri, Begoña; Gómez I Prat, Jordi; Jackson, Yves

2016-05-01

Identifying pregnant women infected with Trypanosoma cruzi is one of the major challenges for preventing and controlling Chagas disease (CD) in non-endemic countries. The aim of this paper was to perform a policy evaluation of the current practices of congenital Chagas disease (CCD) control in non-endemic countries and to propose specific targets for enhanced interventions to tackle this emerging health problem outside the endemic areas of Latin America. We conducted a mixed method review of CCD policy strategies by searching the literature in the PubMed, Google Scholar and the World Health Organization (WHO) databases using the key terms 'CCD', 'paediatric Chagas disease' and 'non-endemic countries'; as free text and combined as one phrase to increase the search sensitivity. Reviews, recommendations, guidelines and control/surveillance programme reports were included. Of 427 CCD papers identified in non-endemic countries, 44 matched the inclusion. Although local programmes were launched in different countries with large numbers of Latin American immigrants, there were considerable disparities in terms of the programmes' distribution, delivery, integration and appropriated CCD control strategies. Moreover, Catalonia, Spain is the only region/country with an established systematic monitoring of CCD in pregnant women from Latin American countries. Given the worldwide dissemination of CD, the nature of its vertical transmission, and the gaps of the current strategies in non-endemic countries, there is an urgent need to standardise, expand and reinforce the control measures against CCD transmission. © 2016 John Wiley & Sons Ltd.

Controlling Infectious Diseases.

ERIC Educational Resources Information Center

Porter, Wm. Lane; Fidler, David P.

1997-01-01

Advocates establishing programs to educate the public about the growing threat of communicable diseases and to promote effective strategies. Utilizes recent successes and failures to formulate those strategies. Profiles three recent infectious disease outbreaks that illustrate some of the current problems. Identifies four ways that lawyers can…

Avoidance and depression vulnerability: An examination of avoidance in remitted and currently depressed individuals.

PubMed

Quigley, Leanne; Wen, Alainna; Dobson, Keith S

2017-10-01

Behavioral theories posit that depression is characterized by heightened levels of avoidance, and recent research has supported this notion. Whether avoidance persists after remission from depression is unknown, however. In this study, we investigated levels of cognitive and behavioral avoidance in remitted, currently, and never depressed individuals. We also examined relationships among avoidance and purported adaptive and maladaptive emotion regulation strategies. Remitted depressed individuals exhibited levels of cognitive and behavioral avoidance, in social and nonsocial domains, that were greater than nonclinical control individuals but lower than currently depressed individuals. Avoidance was significantly associated with use of maladaptive emotion regulation strategies, although the pattern of relationships differed across remitted and currently depressed individuals. In contrast, avoidance was largely unrelated to use of adaptive emotion regulation strategies, among remitted and currently depressed individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling the Cost Effectiveness of Malaria Control Interventions in the Highlands of Western Kenya

PubMed Central

Stuckey, Erin M.; Stevenson, Jennifer; Galactionova, Katya; Baidjoe, Amrish Y.; Bousema, Teun; Odongo, Wycliffe; Kariuki, Simon; Drakeley, Chris; Smith, Thomas A.; Cox, Jonathan; Chitnis, Nakul

2014-01-01

Introduction Tools that allow for in silico optimization of available malaria control strategies can assist the decision-making process for prioritizing interventions. The OpenMalaria stochastic simulation modeling platform can be applied to simulate the impact of interventions singly and in combination as implemented in Rachuonyo South District, western Kenya, to support this goal. Methods Combinations of malaria interventions were simulated using a previously-published, validated model of malaria epidemiology and control in the study area. An economic model of the costs of case management and malaria control interventions in Kenya was applied to simulation results and cost-effectiveness of each intervention combination compared to the corresponding simulated outputs of a scenario without interventions. Uncertainty was evaluated by varying health system and intervention delivery parameters. Results The intervention strategy with the greatest simulated health impact employed long lasting insecticide treated net (LLIN) use by 80% of the population, 90% of households covered by indoor residual spraying (IRS) with deployment starting in April, and intermittent screen and treat (IST) of school children using Artemether lumefantrine (AL) with 80% coverage twice per term. However, the current malaria control strategy in the study area including LLIN use of 56% and IRS coverage of 70% was the most cost effective at reducing disability-adjusted life years (DALYs) over a five year period. Conclusions All the simulated intervention combinations can be considered cost effective in the context of available resources for health in Kenya. Increasing coverage of vector control interventions has a larger simulated impact compared to adding IST to the current implementation strategy, suggesting that transmission in the study area is not at a level to warrant replacing vector control to a school-based screen and treat program. These results have the potential to assist malaria control program managers in the study area in adding new or changing implementation of current interventions. PMID:25290939

Modeling the cost effectiveness of malaria control interventions in the highlands of western Kenya.

PubMed

Stuckey, Erin M; Stevenson, Jennifer; Galactionova, Katya; Baidjoe, Amrish Y; Bousema, Teun; Odongo, Wycliffe; Kariuki, Simon; Drakeley, Chris; Smith, Thomas A; Cox, Jonathan; Chitnis, Nakul

2014-01-01

Tools that allow for in silico optimization of available malaria control strategies can assist the decision-making process for prioritizing interventions. The OpenMalaria stochastic simulation modeling platform can be applied to simulate the impact of interventions singly and in combination as implemented in Rachuonyo South District, western Kenya, to support this goal. Combinations of malaria interventions were simulated using a previously-published, validated model of malaria epidemiology and control in the study area. An economic model of the costs of case management and malaria control interventions in Kenya was applied to simulation results and cost-effectiveness of each intervention combination compared to the corresponding simulated outputs of a scenario without interventions. Uncertainty was evaluated by varying health system and intervention delivery parameters. The intervention strategy with the greatest simulated health impact employed long lasting insecticide treated net (LLIN) use by 80% of the population, 90% of households covered by indoor residual spraying (IRS) with deployment starting in April, and intermittent screen and treat (IST) of school children using Artemether lumefantrine (AL) with 80% coverage twice per term. However, the current malaria control strategy in the study area including LLIN use of 56% and IRS coverage of 70% was the most cost effective at reducing disability-adjusted life years (DALYs) over a five year period. All the simulated intervention combinations can be considered cost effective in the context of available resources for health in Kenya. Increasing coverage of vector control interventions has a larger simulated impact compared to adding IST to the current implementation strategy, suggesting that transmission in the study area is not at a level to warrant replacing vector control to a school-based screen and treat program. These results have the potential to assist malaria control program managers in the study area in adding new or changing implementation of current interventions.

An Optimal Current Observer for Predictive Current Controlled Buck DC-DC Converters

PubMed Central

Min, Run; Chen, Chen; Zhang, Xiaodong; Zou, Xuecheng; Tong, Qiaoling; Zhang, Qiao

2014-01-01

In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally. PMID:24854061

A molecular insight into papaya leaf curl-a severe viral disease.

PubMed

Varun, Priyanka; Ranade, S A; Saxena, Sangeeta

2017-11-01

Papaya leaf curl disease (PaLCuD) caused by papaya leaf curl virus (PaLCuV) not only affects yield but also plant growth and fruit size and quality of papaya and is one of the most damaging and economically important disease. Management of PaLCuV is a challenging task due to diversity of viral strains, the alternate hosts, and the genomic complexities of the viruses. Several management strategies currently used by plant virologists to broadly control or eliminate the viruses have been discussed. In the absence of such strategies in the case of PaLCuV at present, the few available options to control the disease include methods like removal of affected plants from the field, insecticide treatments against the insect vector (Bemisia tabaci), and gene-specific control through transgenic constructs. This review presents the current understanding of papaya leaf curl disease, genomic components including satellite DNA associated with the virus, wide host and vector range, and management of the disease and suggests possible generic resistance strategies.

An Examination of Strategy Implementation During Abstract Nonlinguistic Category Learning in Aphasia

PubMed Central

Kiran, Swathi

2015-01-01

Purpose Our purpose was to study strategy use during nonlinguistic category learning in aphasia. Method Twelve control participants without aphasia and 53 participants with aphasia (PWA) completed a computerized feedback-based category learning task consisting of training and testing phases. Accuracy rates of categorization in testing phases were calculated. To evaluate strategy use, strategy analyses were conducted over training and testing phases. Participant data were compared with model data that simulated complex multi-cue, single feature, and random pattern strategies. Learning success and strategy use were evaluated within the context of standardized cognitive–linguistic assessments. Results Categorization accuracy was higher among control participants than among PWA. The majority of control participants implemented suboptimal or optimal multi-cue and single-feature strategies by testing phases of the experiment. In contrast, a large subgroup of PWA implemented random patterns, or no strategy, during both training and testing phases of the experiment. Conclusions Person-to-person variability arises not only in category learning ability but also in the strategies implemented to complete category learning tasks. PWA less frequently developed effective strategies during category learning tasks than control participants. Certain PWA may have impairments of strategy development or feedback processing not captured by language and currently probed cognitive abilities. PMID:25908438

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.

On the Application of Different Event-Based Sampling Strategies to the Control of a Simple Industrial Process

PubMed Central

Sánchez, José; Guarnes, Miguel Ángel; Dormido, Sebastián

2009-01-01

This paper is an experimental study of the utilization of different event-based strategies for the automatic control of a simple but very representative industrial process: the level control of a tank. In an event-based control approach it is the triggering of a specific event, and not the time, that instructs the sensor to send the current state of the process to the controller, and the controller to compute a new control action and send it to the actuator. In the document, five control strategies based on different event-based sampling techniques are described, compared, and contrasted with a classical time-based control approach and a hybrid one. The common denominator in the time, the hybrid, and the event-based control approaches is the controller: a proportional-integral algorithm with adaptations depending on the selected control approach. To compare and contrast each one of the hybrid and the pure event-based control algorithms with the time-based counterpart, the two tasks that a control strategy must achieve (set-point following and disturbance rejection) are independently analyzed. The experimental study provides new proof concerning the ability of event-based control strategies to minimize the data exchange among the control agents (sensors, controllers, actuators) when an error-free control of the process is not a hard requirement. PMID:22399975

Mitigating Future Avian Malaria Threats to Hawaiian Forest Birds from Climate Change.

PubMed

Liao, Wei; Atkinson, Carter T; LaPointe, Dennis A; Samuel, Michael D

2017-01-01

Avian malaria, transmitted by Culex quinquefasciatus mosquitoes in the Hawaiian Islands, has been a primary contributor to population range limitations, declines, and extinctions for many endemic Hawaiian honeycreepers. Avian malaria is strongly influenced by climate; therefore, predicted future changes are expected to expand transmission into higher elevations and intensify and lengthen existing transmission periods at lower elevations, leading to further population declines and potential extinction of highly susceptible honeycreepers in mid- and high-elevation forests. Based on future climate changes and resulting malaria risk, we evaluated the viability of alternative conservation strategies to preserve endemic Hawaiian birds at mid and high elevations through the 21st century. We linked an epidemiological model with three alternative climatic projections from the Coupled Model Intercomparison Project to predict future malaria risk and bird population dynamics for the coming century. Based on climate change predictions, proposed strategies included mosquito population suppression using modified males, release of genetically modified refractory mosquitoes, competition from other introduced mosquitoes that are not competent vectors, evolved malaria-tolerance in native honeycreepers, feral pig control to reduce mosquito larval habitats, and predator control to improve bird demographics. Transmission rates of malaria are predicted to be higher than currently observed and are likely to have larger impacts in high-elevation forests where current low rates of transmission create a refuge for highly-susceptible birds. As a result, several current and proposed conservation strategies will be insufficient to maintain existing forest bird populations. We concluded that mitigating malaria transmission at high elevations should be a primary conservation goal. Conservation strategies that maintain highly susceptible species like Iiwi (Drepanis coccinea) will likely benefit other threatened and endangered Hawai'i species, especially in high-elevation forests. Our results showed that mosquito control strategies offer potential long-term benefits to high elevation Hawaiian honeycreepers. However, combined strategies will likely be needed to preserve endemic birds at mid elevations. Given the delay required to research, develop, evaluate, and improve several of these currently untested conservation strategies we suggest that planning should begin expeditiously.

Mitigating future avian malaria threats to Hawaiian forest birds from climate change

USGS Publications Warehouse

Liao, Wei; Atkinson, Carter T.; LaPointe, Dennis; Samuel, Michael D.

2017-01-01

Avian malaria, transmitted by Culex quinquefasciatus mosquitoes in the Hawaiian Islands, has been a primary contributor to population range limitations, declines, and extinctions for many endemic Hawaiian honeycreepers. Avian malaria is strongly influenced by climate; therefore, predicted future changes are expected to expand transmission into higher elevations and intensify and lengthen existing transmission periods at lower elevations, leading to further population declines and potential extinction of highly susceptible honeycreepers in mid- and high-elevation forests. Based on future climate changes and resulting malaria risk, we evaluated the viability of alternative conservation strategies to preserve endemic Hawaiian birds at mid and high elevations through the 21st century. We linked an epidemiological model with three alternative climatic projections from the Coupled Model Intercomparison Project to predict future malaria risk and bird population dynamics for the coming century. Based on climate change predictions, proposed strategies included mosquito population suppression using modified males, release of genetically modified refractory mosquitoes, competition from other introduced mosquitoes that are not competent vectors, evolved malaria-tolerance in native honeycreepers, feral pig control to reduce mosquito larval habitats, and predator control to improve bird demographics. Transmission rates of malaria are predicted to be higher than currently observed and are likely to have larger impacts in high-elevation forests where current low rates of transmission create a refuge for highly-susceptible birds. As a result, several current and proposed conservation strategies will be insufficient to maintain existing forest bird populations. We concluded that mitigating malaria transmission at high elevations should be a primary conservation goal. Conservation strategies that maintain highly susceptible species like Iiwi (Drepanis coccinea) will likely benefit other threatened and endangered Hawai’i species, especially in high-elevation forests. Our results showed that mosquito control strategies offer potential long-term benefits to high elevation Hawaiian honeycreepers. However, combined strategies will likely be needed to preserve endemic birds at mid elevations. Given the delay required to research, develop, evaluate, and improve several of these currently untested conservation strategies we suggest that planning should begin expeditiously.

Financial analysis of various strategies for the control of Neospora caninum in dairy cattle in Switzerland.

PubMed

Häsler, Barbara; Regula, Gertraud; Stärk, Katharina D C; Sager, Heinz; Gottstein, Bruno; Reist, Martin

2006-12-18

The present study was conducted to estimate the direct losses due to Neospora caninum in Swiss dairy cattle and to assess the costs and benefits of different potential control strategies. A Monte Carlo simulation spreadsheet module was developed to estimate the direct costs caused by N. caninum, with and without control strategies, and to estimate the costs of these control strategies in a financial analysis. The control strategies considered were "testing and culling of seropositive female cattle", "discontinued breeding with offspring from seropositive cows", "chemotherapeutical treatment of female offspring" and "vaccination of all female cattle". Each parameter in the module that was considered to be uncertain, was described using probability distributions. The simulations were run with 20,000 iterations over a time period of 25 years. The median annual losses due to N. caninum in the Swiss dairy cow population were estimated to be euro 9.7 million euros. All control strategies that required yearly serological testing of all cattle in the population produced high costs and thus were not financially profitable. Among the other control strategies, two showed benefit-cost ratios (BCR) >1 and positive net present values (NPV): "Discontinued breeding with offspring from seropositive cows" (BCR=1.29, NPV=25 million euros ) and "chemotherapeutical treatment of all female offspring" (BCR=2.95, NPV=59 million euros). In economic terms, the best control strategy currently available would therefore be "discontinued breeding with offspring from seropositive cows".

On spacecraft maneuvers control subject to propellant engine modes.

PubMed

Mazinan, A H

2015-09-01

The paper attempts to address a new control approach to spacecraft maneuvers based upon the modes of propellant engine. A realization of control strategy is now presented in engine on mode (high thrusts as well as further low thrusts), which is related to small angle maneuvers and engine off mode (specified low thrusts), which is also related to large angle maneuvers. There is currently a coarse-fine tuning in engine on mode. It is shown that the process of handling the angular velocities are finalized via rate feedback system in engine modes, where the angular rotations are controlled through quaternion based control (QBCL)strategy in engine off mode and these ones are also controlled through an optimum PID (OPIDH) strategy in engine on mode. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Applying PWM to control overcurrents at unbalanced faults of force-commutated VSCs used as static var compensators

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

Jiang, Y.; Ekstroem, A.

1997-01-01

This study is devoted to investigating the possibility of controlling the overcurrent of a forced-commutated voltage source converter (VSC) by PWM when the ac system is undergoing large unbalanced disturbance. The converter is supposed to be used as a static var compensator at a high power level. A novel control strategy is proposed for controlling the reactive current and the dc side voltage independently. Digital simulation results are presented and compared with the results by using just the reactive current control with fundamental switching frequency.

The Political Economy of the Ebola Virus Disease (EVD); Taking Individual and Community Ownership in the Prevention and Control of EVD.

PubMed

Obilade, Titilola T

2015-01-28

The outbreak of an emerging infectious disease of zoonotic origin has exposed the weaknesses in the health systems of the nations affected. The purpose of this paper was to explore the political economy of the existing outcome of the management strategies. In addition, it proposed a new strategy in the management of the current Ebola virus disease (EVD) outbreak. This paper admits that the current management strategy which is a top to bottom approach has not worked in reducing the spread of the disease. Instead of waiting for the disease before treatment is commenced, this paper suggests aggressively preventing infection from the EVD. It presents a bottom to top approach where there is individual ownership and community ownership in the prevention and control of the EVD outbreak. In addition, the paper presents the socio-economic situation of the three most affected countries including the ecology and stigmatization of EVD. It highlights the need for cross border surveillance across the West African nations to prevent importation of the disease as occurred in Nigeria and Senegal. It points out the need for aggressive international cooperation, an aggressive prevention and a sustainable control strategy.

The Political Economy of the Ebola Virus Disease (EVD); Taking Individual and Community Ownership in the Prevention and Control of EVD

PubMed Central

Obilade, Titilola T.

2015-01-01

The outbreak of an emerging infectious disease of zoonotic origin has exposed the weaknesses in the health systems of the nations affected. The purpose of this paper was to explore the political economy of the existing outcome of the management strategies. In addition, it proposed a new strategy in the management of the current Ebola virus disease (EVD) outbreak. This paper admits that the current management strategy which is a top to bottom approach has not worked in reducing the spread of the disease. Instead of waiting for the disease before treatment is commenced, this paper suggests aggressively preventing infection from the EVD. It presents a bottom to top approach where there is individual ownership and community ownership in the prevention and control of the EVD outbreak. In addition, the paper presents the socio-economic situation of the three most affected countries including the ecology and stigmatization of EVD. It highlights the need for cross border surveillance across the West African nations to prevent importation of the disease as occurred in Nigeria and Senegal. It points out the need for aggressive international cooperation, an aggressive prevention and a sustainable control strategy. PMID:27417746

Managing young children's snack food intake. The role of parenting style and feeding strategies.

PubMed

Boots, Samantha B; Tiggemann, Marika; Corsini, Nadia; Mattiske, Julie

2015-09-01

One major contributor to the problem of childhood overweight and obesity is the over-consumption of foods high in fat, salt and sugar, such as snack foods. The current study aimed to examine young children's snack intake and the influence of feeding strategies used by parents in the context of general parenting style. Participants were 611 mothers of children aged 2-7 years who completed an online questionnaire containing measures of general parenting domains and two particular feeding strategies, restriction and covert control. It was found that greater unhealthy snack intake was associated with higher restriction and lower covert control, while greater healthy snack intake was associated with lower restriction and higher covert control. Further, the feeding strategies mediated the association between parental demandingness and responsiveness and child snack intake. These findings provide evidence for the differential impact of controlling and positive parental feeding strategies on young children's snack intake in the context of general parenting. Copyright © 2015 Elsevier Ltd. All rights reserved.

Schistosomiasis elimination strategies and potential role of a vaccine in achieving global health goals.

PubMed

Mo, Annie X; Agosti, Jan M; Walson, Judd L; Hall, B Fenton; Gordon, Lance

2014-01-01

In March 2013, the National Institute of Allergy and Infectious Diseases and the Bill and Melinda Gates Foundation co-sponsored a meeting entitled "Schistosomiasis Elimination Strategy and Potential Role of a Vaccine in Achieving Global Health Goals" to discuss the potential role of schistosomiasis vaccines and other tools in the context of schistosomiasis control and elimination strategies. It was concluded that although schistosomiasis elimination in some focal areas may be achievable through current mass drug administration programs, global control and elimination will face several significant scientific and operational challenges, and will require an integrated approach with other, additional interventions. These challenges include vector (snail) control; environmental modification; water, sanitation, and hygiene; and other future innovative tools such as vaccines. Defining a clear product development plan that reflects a vaccine strategy as complementary to the existing control programs to combat different forms of schistosomiasis will be important to develop a vaccine effectively.

Control of oil spills in high speed currents : a technology assessment

DOT National Transportation Integrated Search

1999-05-01

A technology assessment has been conducted to analyze the threat of oil spills in fast currents. Technologies and methods for response were evaluated, and promising equipment and strategies were identified. Recommendations are made to pursue those me...

The Impact of Transformer Winding Connections of A Grid-Connected PV on Voltage Quality Improvement

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

Muljadi, Eduard; Tumbelaka, Hanny H.; Gao, Wenzhong

In this paper, the high-power PV plant is connected to the weak grid by means of a three-phase power transformer. The selection of transformer winding connection is critical especially when the PV inverter has a reactive power controller. In general, transformer winding connection can be arranged in star-star (with neutral earthed) or star-delta. The reactive power controller supports voltage regulation of the power system particularly under transient faults. Its control strategy is based on utilizing the grid currents to make a three-phase reactive unbalanced current with a small gain. The gain is determined by the system impedance. Simulation results exhibitmore » that the control strategy works very well particularly under disturbance conditions when the transformer winding connection is star-star with both neutrals grounded. The power quality in terms of the voltage quality is improved.« less

PWM Switching Strategy for Torque Ripple Minimization in BLDC Motor

NASA Astrophysics Data System (ADS)

Salah, Wael A.; Ishak, Dahaman; Hammadi, Khaleel J.

2011-05-01

This paper describes a new PWM switching strategy to minimize the torque ripples in BLDC motor which is based on sensored rotor position control. The scheme has been implemented using a PIC microcontroller to generate a modified Pulse Width Modulation (PWM) signals for driving power inverter bridge. The modified PWM signals are successfully applied to the next up-coming phase current such that its current rise is slightly delayed during the commutation instant. Experimental results show that the current waveforms of the modified PWM are smoother than that in conventional PWM technique. Hence, the output torque exhibits lower ripple contents.

Novel MSVPWM to reduce the inductor current ripple for Z-source inverter in electric vehicle applications.

PubMed

Zhang, Qianfan; Dong, Shuai; Xue, Ping; Zhou, Chaowei; Cheng, ShuKang

2014-01-01

A novel modified space vector pulse width modulation (MSVPWM) strategy for Z-Source inverter is presented. By rearranging the position of shoot-through states, the frequency of inductor current ripple is kept constant. Compared with existing MSVPWM strategies, the proposed approach can reduce the maximum inductor current ripple. So the volume of Z-source network inductor can be designed smaller, which brings the beneficial effect on the miniaturization of the electric vehicle controller. Theoretical findings in the novel MSVPWM for Z-Source inverter have been verified by experiment results.

Novel MSVPWM to Reduce the Inductor Current Ripple for Z-Source Inverter in Electric Vehicle Applications

PubMed Central

Zhang, Qianfan; Dong, Shuai; Xue, Ping; Zhou, Chaowei; Cheng, ShuKang

2014-01-01

A novel modified space vector pulse width modulation (MSVPWM) strategy for Z-Source inverter is presented. By rearranging the position of shoot-through states, the frequency of inductor current ripple is kept constant. Compared with existing MSVPWM strategies, the proposed approach can reduce the maximum inductor current ripple. So the volume of Z-source network inductor can be designed smaller, which brings the beneficial effect on the miniaturization of the electric vehicle controller. Theoretical findings in the novel MSVPWM for Z-Source inverter have been verified by experiment results. PMID:24883412

Global assessment of schistosomiasis control over the past century shows targeting the snail intermediate host works best

USGS Publications Warehouse

Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Swartz, Scott J.; Lopez, Melina; Hsieh, Michael H.; Lafferty, Kevin D.; Kuris, Armand M.; Rickards, Chloe; De Leo, Giulio A.

2016-01-01

Snail control has been the most effective way to reduce schistosomiasis prevalence. Despite evidence that snail control leads to long-term disease reduction and elimination, most current schistosomiasis control efforts emphasize MDA using praziquantel over snail control. Combining drug-based control programs with affordable snail control seems the best strategy for eliminating schistosomiasis.

‘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

Formation Flying in Earth, Libration, and Distant Retrograde Orbits

NASA Technical Reports Server (NTRS)

Folta, David C.

2004-01-01

This slide presentation examines the current and future state of formation flying, LEO formations, control strategies for flight in the vicinity of the libration points, and distant retrograde orbit formations. This discussion of LEO formations includes background on perturbation theory/accelerations and LEO formation flying. The discussion of strategies for formation flight in the vicinity of the libration points includes libration missions and natural and controlled libration orbit formations. A reference list is included.

Renal Sympathetic Denervation – A Review of Applications in Current Practice

PubMed Central

Kapil, Vikas; Jain, Ajay K

2014-01-01

Resistant hypertension is associated with high morbidity and mortality despite numerous pharmacological strategies. A wealth of preclinical and clinical data have demonstrated that resistant hypertension is associated with elevated renal and central sympathetic tone. The development of interventional therapies to modulate the sympathetic nervous system potentially represents a paradigm shift in the strategy for blood pressure control in this subset of patients. Initial first-in-man and pivotal, randomised controlled trials of endovascular, radio-frequency renal sympathetic denervation have spawned numerous iterations of similar technology, as well as many novel concepts for achieving effective renal sympatholysis. This review details the current knowledge of these devices and the evidence base behind each technology. PMID:29588780

Advanced Research Projects Agency counterdrug program

NASA Astrophysics Data System (ADS)

Pennella, John J.

1994-03-01

The Department of Defense (DoD), in support of the National Drug Control Strategy, has designated that detecting and countering the production, trafficking and use of illegal drugs is a high priority national security mission. The Advanced Research Projects Agency (ARPA) Counterdrug Program is assisting DoD in this objective by developing technology and prototype systems to enhance the capabilities of the DoD and civilian law enforcement agencies, consistent with the DoD mission and the supply reduction goals of the National Drug Control Strategy. The objective of this paper is to summarize the current ARPA Counterdrug Program, with special emphasis on the current efforts and future plans for developing technology to meet the National needs for Non-Intrusive Inspection.

New charging strategy for lithium-ion batteries based on the integration of Taguchi method and state of charge estimation

NASA Astrophysics Data System (ADS)

Vo, Thanh Tu; Chen, Xiaopeng; Shen, Weixiang; Kapoor, Ajay

2015-01-01

In this paper, a new charging strategy of lithium-polymer batteries (LiPBs) has been proposed based on the integration of Taguchi method (TM) and state of charge estimation. The TM is applied to search an optimal charging current pattern. An adaptive switching gain sliding mode observer (ASGSMO) is adopted to estimate the SOC which controls and terminates the charging process. The experimental results demonstrate that the proposed charging strategy can successfully charge the same types of LiPBs with different capacities and cycle life. The proposed charging strategy also provides much shorter charging time, narrower temperature variation and slightly higher energy efficiency than the equivalent constant current constant voltage charging method.

A systematic review of studies evaluating diffusion and dissemination of selected cancer control interventions.

PubMed

Ellis, Peter; Robinson, Paula; Ciliska, Donna; Armour, Tanya; Brouwers, Melissa; O'Brien, Mary Ann; Sussman, Jonathan; Raina, Parminder

2005-09-01

With this review, the authors sought to determine what strategies have been evaluated (including the outcomes assessed) to disseminate cancer control interventions that promote the uptake of behavior change. Five topic areas along the cancer care continuum (smoking cessation, healthy diet, mammography, cervical cancer screening, and control of cancer pain) were selected to be representative. A systematic review was conducted of primary studies evaluating dissemination of a cancer control intervention. Thirty-one studies were identified that evaluated dissemination strategies in the 5 topic areas. No strong evidence currently exists to recommend any one dissemination strategy as effective in promoting the uptake of cancer control interventions. The authors conclude that there is a strong need for more research into dissemination of cancer control interventions. Future research should consider methodological issues such as the most appropriate study design and outcomes to be evaluated. (c) 2005 APA, all rights reserved

A Review of Control Strategies in Closed-Loop Neuroprosthetic Systems

PubMed Central

Wright, James; Macefield, Vaughan G.; van Schaik, André; Tapson, Jonathan C.

2016-01-01

It has been widely recognized that closed-loop neuroprosthetic systems achieve more favorable outcomes for users then equivalent open-loop devices. Improved performance of tasks, better usability, and greater embodiment have all been reported in systems utilizing some form of feedback. However, the interdisciplinary work on neuroprosthetic systems can lead to miscommunication due to similarities in well-established nomenclature in different fields. Here we present a review of control strategies in existing experimental, investigational and clinical neuroprosthetic systems in order to establish a baseline and promote a common understanding of different feedback modes and closed-loop controllers. The first section provides a brief discussion of feedback control and control theory. The second section reviews the control strategies of recent Brain Machine Interfaces, neuromodulatory implants, neuroprosthetic systems, and assistive neurorobotic devices. The final section examines the different approaches to feedback in current neuroprosthetic and neurorobotic systems. PMID:27462202

Space Weather Influence on Relative Motion Control using the Touchless Electrostatic Tractor

NASA Astrophysics Data System (ADS)

Hogan, Erik A.; Schaub, Hanspeter

2016-09-01

With recent interest in the use of electrostatic forces for contactless tugging and attitude control of noncooperative objects for orbital servicing and active debris mitigation, the need for a method of remote charge control arises. In this paper, the use of a directed electron beam for remote charge control is considered in conjunction with the relative motion control. A tug vehicle emits an electron beam onto a deputy object, charging it negatively. At the same time, the tug is charged positively due to beam emission, resulting in an attractive electrostatic force. The relative position feedback control between the tug and the passive debris object is studied subject to the charging being created through an electron beam. Employing the nominal variations of the GEO space weather conditions across longitude slots, two electrostatic tugging strategies are considered. First, the electron beam current is adjusted throughout the orbit in order to maximize this resulting electrostatic force. This open-loop control strategy compensates for changes in the nominally expected local space weather environment in the GEO region to adjust for fluctuations in the local plasma return currents. Second, the performance impact of using a fixed electron beam current on the electrostatic tractor is studied if the same natural space weather variations are assumed. The fixed electron beam current shows a minor performance penalty (<5 %) while providing a much simpler implementation that does not require any knowledge of local space weather conditions.

Electrically heated particulate filter restart strategy

DOEpatents

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2011-07-12

A control system that controls regeneration of a particulate filter is provided. The system generally includes a propagation module that estimates a propagation status of combustion of particulate matter in the particulate filter. A regeneration module controls current to the particulate filter to re-initiate regeneration based on the propagation status.

Nonlinear Recurrent Neural Network Predictive Control for Energy Distribution of a Fuel Cell Powered Robot

PubMed Central

Chen, Qihong; Long, Rong; Quan, Shuhai

2014-01-01

This paper presents a neural network predictive control strategy to optimize power distribution for a fuel cell/ultracapacitor hybrid power system of a robot. We model the nonlinear power system by employing time variant auto-regressive moving average with exogenous (ARMAX), and using recurrent neural network to represent the complicated coefficients of the ARMAX model. Because the dynamic of the system is viewed as operating- state- dependent time varying local linear behavior in this frame, a linear constrained model predictive control algorithm is developed to optimize the power splitting between the fuel cell and ultracapacitor. The proposed algorithm significantly simplifies implementation of the controller and can handle multiple constraints, such as limiting substantial fluctuation of fuel cell current. Experiment and simulation results demonstrate that the control strategy can optimally split power between the fuel cell and ultracapacitor, limit the change rate of the fuel cell current, and so as to extend the lifetime of the fuel cell. PMID:24707206

An Introduction to Intelligent Processing Programs Developed by the Air Force Manufacturing Technology Directorate

NASA Technical Reports Server (NTRS)

Sampson, Paul G.; Sny, Linda C.

1992-01-01

The Air Force has numerous on-going manufacturing and integration development programs (machine tools, composites, metals, assembly, and electronics) which are instrumental in improving productivity in the aerospace industry, but more importantly, have identified strategies and technologies required for the integration of advanced processing equipment. An introduction to four current Air Force Manufacturing Technology Directorate (ManTech) manufacturing areas is provided. Research is being carried out in the following areas: (1) machining initiatives for aerospace subcontractors which provide for advanced technology and innovative manufacturing strategies to increase the capabilities of small shops; (2) innovative approaches to advance machine tool products and manufacturing processes; (3) innovative approaches to advance sensors for process control in machine tools; and (4) efforts currently underway to develop, with the support of industry, the Next Generation Workstation/Machine Controller (Low-End Controller Task).

Systems and methods for providing power to a load based upon a control strategy

DOEpatents

Perisic, Milun; Lawrence, Christopher P; Ransom, Ray M; Kajouke, Lateef A

2014-11-04

Systems and methods are provided for an electrical system. The electrical system, for example, includes a first load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage through the interface and to provide a voltage and current to the first load. The controller may be further configured to, receive information on a second load electrically connected to the voltage source, determine an amount of reactive current to return to the voltage source such that a current drawn by the electrical system and the second load from the voltage source is substantially real, and provide the determined reactive current to the voltage source.

Atrial fibrillation and stroke: the evolving role of rhythm control.

PubMed

Patel, Taral K; Passman, Rod S

2013-06-01

Atrial fibrillation (AF) remains a major risk factor for stroke. Unfortunately, clinical trials have failed to demonstrate that a strategy of rhythm control--therapy to maintain normal sinus rhythm (NSR)--reduces stroke risk. The apparent lack of benefit of rhythm control likely reflects the difficulty in maintaining NSR using currently available therapies. However, there are signals from several trials that the presence of NSR is indeed beneficial and associated with better outcomes related to stroke and mortality. Most electrophysiologists feel that as rhythm control strategies continue to improve, the crucial link between rhythm control and stroke reduction will finally be demonstrated. Therefore, AF specialists tend to be aggressive in their attempts to maintain NSR, especially in patients who have symptomatic AF. A step-wise approach from antiarrhythmic drugs to catheter ablation to cardiac surgery is generally used. In select patients, catheter ablation or cardiac surgery may supersede antiarrhythmic drugs. The choice depends on the type of AF, concurrent heart disease, drug toxicity profiles, procedural risks, and patient preferences. Regardless of strategy, given the limited effectiveness of currently available rhythm control therapies, oral anticoagulation is still recommended for stroke prophylaxis in AF patients with other stroke risk factors. Major challenges in atrial fibrillation management include selecting patients most likely to benefit from rhythm control, choosing specific antiarrhythmic drugs or procedures to achieve rhythm control, long-term monitoring to gauge the efficacy of rhythm control, and determining which (if any) patients may safely discontinue anticoagulation if long-term NSR is achieved.

Economic Effects of Introducing Alternative Salmonella Control Strategies in Sweden

PubMed Central

Sundström, Kristian; Wahlström, Helene; Ivarsson, Sofie; Sternberg Lewerin, Susanna

2014-01-01

The objective of the study was to analyse the economic effects of introducing alternative Salmonella control strategies in Sweden. Current control strategies in Denmark and the Netherlands were used as benchmarks. The true number of human Salmonella cases was estimated by reconstructing the reporting pyramids for the various scenarios. Costs were calculated for expected changes in human morbidity (Salmonella and two of its sequelae), for differences in the control programmes and for changes in cattle morbidity. The net effects (benefits minus costs) were negative in all scenarios (€ −5 to −105 million), implying that it would not be cost-effective to introduce alternative control strategies in Sweden. This result was mainly due to an expected increase in the incidence of Salmonella in humans (6035–57108 reported and unreported new cases/year), with expected additional costs of € 5–55 million. Other increased costs were due to expected higher incidences of sequelae (€ 3–49 million) and a higher cattle morbidity (€ 4–8 million). Benefits in terms of lower control costs amounted to € 4–7 million. PMID:24831797

Strategies for Perceiving Facial Expressions in Adults with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Walsh, Jennifer A.; Vida, Mark D.; Rutherford, M. D.

2014-01-01

Rutherford and McIntosh (J Autism Dev Disord 37:187-196, 2007) demonstrated that individuals with autism spectrum disorder (ASD) are more tolerant than controls of exaggerated schematic facial expressions, suggesting that they may use an alternative strategy when processing emotional expressions. The current study was designed to test this finding…

Variable strategy model of the human operator

NASA Astrophysics Data System (ADS)

Phillips, John Michael

Human operators often employ discontinuous or "bang-bang" control strategies when performing large-amplitude acquisition tasks. The current study applies Variable Structure Control (VSC) techniques to model human operator behavior during acquisition tasks. The result is a coupled, multi-input model replicating the discontinuous control strategy. In the VSC formulation, a switching surface is the mathematical representation of the operator's control strategy. The performance of the Variable Strategy Model (VSM) is evaluated by considering several examples, including the longitudinal control of an aircraft during the visual landing task. The aircraft landing task becomes an acquisition maneuver whenever large initial offsets occur. Several different strategies are explored in the VSM formulation for the aircraft landing task. First, a switching surface is constructed from literal interpretations of pilot training literature. This approach yields a mathematical representation of how a pilot is trained to fly a generic aircraft. This switching surface is shown to bound the trajectory response of a group of pilots performing an offset landing task in an aircraft simulator study. Next, front-side and back-side landing strategies are compared. A back-side landing strategy is found to be capable of landing an aircraft flying on either the front side or back side of the power curve. However, the front-side landing strategy is found to be insufficient for landing an aircraft flying on the back side. Finally, a more refined landing strategy is developed that takes into the account the specific aircraft's dynamic characteristics. The refined strategy is translated back into terminology similar to the existing pilot training literature.

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.

Current status of Marek's disease in the united states and worldwide

USDA-ARS?s Scientific Manuscript database

A questionnaire was widely distributed in 2011 to estimate the global prevalence of Marek’s disease and gain a better understanding of current control strategies and future concerns. A total of 104 questionnaires were returned representing 108 countries from sources including national branch secret...

Analysis of Decentralized Variable Structure Control for Collective Search by Mobile Robots

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

Feddema, J.; Goldsmith, S.; Robinett, R.

1998-11-04

This paper presents an analysis of a decentralized coordination strategy for organizing and controlling a team of mobile robots performing collective search. The alpha-beta coordination strategy is a family of collective search algorithms that allow teams of communicating robots to implicitly coordinate their search activities through a division of labor based on self-selected roIes. In an alpha-beta team. alpha agents are motivated to improve their status by exploring new regions of the search space. Beta a~ents are conservative, and reiy on the alpha agents to provide advanced information on favorable regions of the search space. An agent selects its currentmore » role dynamically based on its current status value relative to the current status values of the other team members. Status is determined by some function of the agent's sensor readings, and is generally a measurement of source intensity at the agent's current location. Variations on the decision rules determining alpha and beta behavior produce different versions of the algorithm that lead to different global properties. The alpha-beta strategy is based on a simple finite-state machine that implements a form of Variable Structure Control (VSC). The VSC system changes the dynamics of the collective system by abruptly switching at defined states to alternative control laws . In VSC, Lyapunov's direct method is often used to design control surfaces which guide the system to a given goal. We introduce the alpha-beta aIgorithm and present an analysis of the equilibrium point and the global stability of the alpha-beta algorithm based on Lyapunov's method.« less

Private Speech Moderates the Effects of Effortful Control on Emotionality

ERIC Educational Resources Information Center

Day, Kimberly L.; Smith, Cynthia L.; Neal, Amy; Dunsmore, Julie C.

2018-01-01

Research Findings: In addition to being a regulatory strategy, children's private speech may enhance or interfere with their effortful control used to regulate emotion. The goal of the current study was to investigate whether children's private speech during a selective attention task moderated the relations of their effortful control to their…

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.

An Assessment of Talent Management Practices Targeting GS-12/13 Level Members of the Army Acquisition Corps Workforce

DTIC Science & Technology

2010-05-01

currently valid OMB control number. 1. REPORT DATE MAY 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND SUBTITLE An... Control , Strategy or Vision, Challenging Work, Collaboration or Teamwork, Work Culture, Shared Gains, Communication, Concern for People, Technology...As show in Figure 5, the top recruiting strategy, selected by both groups, was an emphasis on flex telework or telecommute programs (Holtshouse, 2009

Constant voltage and constant current control implementation for electric vehicles (evs) wireless charger

NASA Astrophysics Data System (ADS)

Tampubolon, Marojahan; Pamungkas, Laskar; Hsieh, Yao Ching; Chiu, Huang Jen

2018-04-01

This paper presents the implementation of Constant Voltage (CV) and Constant Current (CC) control for a wireless charger system. A battery charging system needs these control modes to ensure the safety of the battery and the effectiveness of the charging system. Here, the wireless charger system does not employ any post-regulator stage to control the output voltage and output current of the charger. But, it uses a variable frequency control incorporated with a conventional PI control. As a result, the size and the weight of the system are reduced. This paper discusses the brief review of the SS-WPT, control strategy and implementation of the CV and CC control. Experimental hardware with 2kW output power has been performed and tested. The results show that the proposed CV and CC control method works well with the system.

Clustering, climate and dengue transmission.

PubMed

Junxiong, Pang; Yee-Sin, Leo

2015-06-01

Dengue is currently the most rapidly spreading vector-borne disease, with an increasing burden over recent decades. Currently, neither a licensed vaccine nor an effective anti-viral therapy is available, and treatment largely remains supportive. Current vector control strategies to prevent and reduce dengue transmission are neither efficient nor sustainable as long-term interventions. Increased globalization and climate change have been reported to influence dengue transmission. In this article, we reviewed the non-climatic and climatic risk factors which facilitate dengue transmission. Sustainable and effective interventions to reduce the increasing threat from dengue would require the integration of these risk factors into current and future prevention strategies, including dengue vaccination, as well as the continuous support and commitment from the political and environmental stakeholders.

Colloquia | Cancer Prevention Fellowship Program

Cancer.gov

The Cancer Prevention and Control Colloquia Series features current research findings from guest researchers from a variety of research disciplines. Topics cover current challenges and methods used by investigators to address gaps, advance the field of cancer prevention and control, and promote the application of successful strategies. When Usually twice a month on Tuesday from 11:00 am - noon between September and June. Where NCI's Shady Grove Campus, 9609 Medical Center Drive, Rockville, MD (conference room locations vary).

Open and Shut: The Case for Optimizing Air Component Resilient Basing Strategies in an Anti-Access/Area Denial Operating Environment

DTIC Science & Technology

2018-04-09

The research focuses on gaps in current doctrine, command relationships, command and control, force structure of ABO forces, posture, training for...identifying conceptual challenges and methodologies to address them as well as describing areas for further research . 15. SUBJECT TERMS Airbase Opening...Denial environment. The research focuses on gaps in current doctrine, command relationships, command and control, force structure of ABO forces

Space Station Freedom altitude strategy

NASA Technical Reports Server (NTRS)

Mcdonald, Brian M.; Teplitz, Scott B.

1990-01-01

The Space Station Freedom (SSF) altitude strategy provides guidelines and assumptions to determine an altitude profile for Freedom. The process for determining an altitude profile incorporates several factors such as where the Space Shuttle will rendezvous with the SSF, when reboosts must occur, and what atmospheric conditions exist causing decay. The altitude strategy has an influence on all areas of SSF development and mission planning. The altitude strategy directly affects the micro-gravity environment for experiments, propulsion and control system sizing, and Space Shuttle delivery manifests. Indirectly the altitude strategy influences almost every system and operation within the Space Station Program. Evolution of the SSF altitude strategy has been a very dynamic process over the past few years. Each altitude strategy in turn has emphasized a different consideration. Examples include a constant Space Shuttle rendezvous altitude for mission planning simplicity, or constant micro-gravity levels with its inherent emphasis on payloads, or lifetime altitudes to provide a safety buffer to loss of control conditions. Currently a new altitude strategy is in development. This altitude strategy will emphasize Space Shuttle delivery optimization. Since propellant is counted against Space Shuttle payload-to-orbit capacity, lowering the rendezvous altitude will not always increase the net payload-to-orbit, since more propellant would be required for reboost. This altitude strategy will also consider altitude biases to account for Space Shuttle launch slips and an unexpected worsening of atmospheric conditions. Safety concerns will define a lower operational altitude limit, while radiation levels will define upper altitude constraints. The evolution of past and current SSF altitude strategies and the development of a new altitude strategy which focuses on operational issues as opposed to design are discussed.

Analysis and Control of Pulse-Width Modulated AC to DC Voltage Source Converters.

NASA Astrophysics Data System (ADS)

Wu, Rusong

The pulse width modulated AC to DC voltage source converter is comprehensively analyzed in the thesis. A general mathematical model of the converter is first established, which is discontinuous, time-variant and non-linear. The following three techniques are used to obtain closed form solutions: Fourier analysis, transformation of reference frame and small signal linearization. Three models, namely, a steady-state DC model, a low frequency small signal AC model and a high frequency model, are consequently developed. Finally, three solution sets, namely, the steady-state solution, various dynamic transfer functions and the high frequency harmonic components, are obtained from the three models. Two control strategies, the Phase and Amplitude Control (PAC) and a new proposed strategy, Predicted Current Control with a Fixed Switching Frequency (PCFF), are investigated. Based on the transfer functions derived from the above mentioned analysis, regulators for a closed-loop control are designed. A prototype circuit is built to experimentally verify the theoretical predictions. The analysis and experimental results show that both strategies produce nearly sinusoidal line current with unity power factor on the utility side in both rectifying and regenerating operations and concurrently provide a regulated DC output voltage on the load side. However the proposed PCFF control has a faster and improved dynamic response over the PAC control. Moreover it is also easier to be implemented. Therefore, the PCFF control is preferable to the PAC control. As an example of application, a configuration of variable DC supply under PCFF control is proposed. The quasi-optimal dynamic response obtained shows that the PWM AC to DC converter lays the foundation for building a four-quadrant, fast-dynamic system, and the PCFF control is an effective strategy for improving dynamic performances not only as applied to the AC to DC converter, but also as applied to the DC to DC chopper or other circuits.

Schistosomiasis Elimination Strategies and Potential Role of a Vaccine in Achieving Global Health Goals

PubMed Central

Mo, Annie X.; Agosti, Jan M.; Walson, Judd L.; Hall, B. Fenton; Gordon, Lance

2014-01-01

In March 2013, the National Institute of Allergy and Infectious Diseases and the Bill and Melinda Gates Foundation co-sponsored a meeting entitled “Schistosomiasis Elimination Strategy and Potential Role of a Vaccine in Achieving Global Health Goals” to discuss the potential role of schistosomiasis vaccines and other tools in the context of schistosomiasis control and elimination strategies. It was concluded that although schistosomiasis elimination in some focal areas may be achievable through current mass drug administration programs, global control and elimination will face several significant scientific and operational challenges, and will require an integrated approach with other, additional interventions. These challenges include vector (snail) control; environmental modification; water, sanitation, and hygiene; and other future innovative tools such as vaccines. Defining a clear product development plan that reflects a vaccine strategy as complementary to the existing control programs to combat different forms of schistosomiasis will be important to develop a vaccine effectively. PMID:24402703

Robust shrinking ellipsoid model predictive control for linear parameter varying system

PubMed Central

Yan, Yan

2017-01-01

In this paper, a new off-line model predictive control strategy is presented for a kind of linear parameter varying system with polytopic uncertainty. A nest of shrinking ellipsoids is constructed by solving linear matrix inequality. By splitting the objective function into two parts, the proposed strategy moves most computations off-line. The on-line computation is only calculating the current control to assure the system shrinking into the smaller ellipsoid. With the proposed formulation, the stability of the closed system is proved, followed with two numerical examples to demonstrate the proposed method’s effectiveness in the end. PMID:28575028

Emotion Regulation in Current and Remitted Depression: A Systematic Review and Meta-Analysis

PubMed Central

Visted, Endre; Vøllestad, Jon; Nielsen, Morten Birkeland; Schanche, Elisabeth

2018-01-01

Background: Major Depressive Disorder (MDD) is a highly prevalent, recurrent, and potentially chronic disorder. Identifying risk factors and underlying mechanisms to inform preventive and therapeutic interventions is therefore imperative. Emotion regulation is a proposed factor in the development and maintenance of MDD. The aim of the present review was to summarize and synthesize research on self-reported emotion regulation strategy use and emotion regulation abilities in adults diagnosed with current and remitted MDD. Methods: Seventy-two eligible studies were retrieved from databases through a systematic literature search. Group differences between individuals with current MDD, remitted MDD, and healthy controls were calculated using meta-analytic procedures. Meta-regression analyses investigated potential moderator effects on emotion regulation difficulties. Results: Results indicated that individuals with current MDD report higher maladaptive emotion regulation strategy use for avoidance (Hedges' g = 1.3), rumination (g = 2.1), and suppression (g = 1.1) compared to healthy controls. Also, they reported lower adaptive emotion regulation strategy use for acceptance (g = −1.0), problem solving (g = −1.0), and reappraisal (g = −0.7). Individuals with current MDD reported limited general emotion regulation abilities, indicated by higher alexithymia (g = 1.45), lower emotional awareness (g = −0.95), emotional clarity (g = −1.50) and emotional tolerance (g = −1.89). Similar results were found in individuals with remitted MDD for avoidance (g = 1.0), rumination (g = 1.1), suppression (g = 0.6), and general emotion regulation abilities. However, no difference was found between individuals with remitted MDD and healthy controls for adaptive emotion regulation strategies. Meta-regression analyses suggest that age of illness onset, comorbid anxiety and duration of remission influence emotion regulation. Conclusion: The present review and meta-analysis indicates that individuals with current and remitted MDD have difficulties with emotion regulation compared to individuals who have never been depressed. Although depressive symptoms improve, emotion regulation difficulties may continue, and could be a contributing factor to relapse. Our findings inform future research on emotion regulation and psychotherapeutic interventions. PMID:29867700

Best Practices for Controlling Lead and Copper Release

EPA Science Inventory

Presentation draft, covering summary of current state-of-the-art knowledge for the best treatment strategies for minimizing lead release and controlling copper release. The presentation is intended to aid with compliance with the Lead and Copper Rule, but also provide a guide to...

Engineering Immunity: Modulating Dendritic Cell Subsets and Lymph Node Response to Direct Immune-polarization and Vaccine Efficacy

PubMed Central

Leleux, Jardin; Atalis, Alexandra; Roy, Krishnendu

2017-01-01

While successful vaccines have been developed against many pathogens, there are still many diseases and pathogenic infections that are highly evasive to current vaccination strategies. Thus, more sophisticated approaches to control the type and quality of vaccine-induced immune response must be developed. Dendritic cells (DCs) are the sentinels of the body and play a critical role in immune response generation and direction by bridging innate and adaptive immunity. It is now well recognized that DCs can be separated into many subgroups, each of which has a unique function. Better understanding of how various DC subsets, in lymphoid organs and in the periphery, can be targeted through controlled delivery; and how these subsets modulate and control the resulting immune response could greatly enhance our ability to develop new, effective vaccines against complex diseases. In this review, we provide an overview of DC subset biology and discuss current immunotherapeutic strategies that utilize DC targeting to modulate and control immune responses. PMID:26489733

High-performance fractional order terminal sliding mode control strategy for DC-DC Buck converter

PubMed Central

Xu, Dan; Zhou, Huan; Bai, Anning; Lu, Wei

2017-01-01

This paper presents an adaption of the fractional order terminal sliding mode control (AFTSMC) strategy for DC-DC Buck converter. The following strategy aims to design a novel nonlinear sliding surface function, with a double closed-loop structure of voltage and current. This strategy is a fusion of two characteristics: terminal sliding mode control (TSMC) and fractional order calculation (FOC). In addition, the influence of “the controller parameters” on the “performance of double closed-loop system” is investigated. It is observed that the value of terminal power has to be chosen to make a compromise between start-up and transient response of the converter. Therefore the AFTSMC strategy chooses the value of the terminal power adaptively, and this strategy can lead to the appropriate number of fractional order as well. Furthermore, through the fractional order analysis, the system can reach the sliding mode surface in a finite time. And the theoretical considerations are verified by numerical simulation. The performance of the AFTSMC and TSMC strategies is tested by computer simulations. And the comparison simulation results show that the AFTSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes. Moreover, AFTSMC obtains a faster dynamical response, smaller steady-state error rate and lower overshoot. PMID:29084255

High-performance fractional order terminal sliding mode control strategy for DC-DC Buck converter.

PubMed

Wang, Jianlin; Xu, Dan; Zhou, Huan; Bai, Anning; Lu, Wei

2017-01-01

This paper presents an adaption of the fractional order terminal sliding mode control (AFTSMC) strategy for DC-DC Buck converter. The following strategy aims to design a novel nonlinear sliding surface function, with a double closed-loop structure of voltage and current. This strategy is a fusion of two characteristics: terminal sliding mode control (TSMC) and fractional order calculation (FOC). In addition, the influence of "the controller parameters" on the "performance of double closed-loop system" is investigated. It is observed that the value of terminal power has to be chosen to make a compromise between start-up and transient response of the converter. Therefore the AFTSMC strategy chooses the value of the terminal power adaptively, and this strategy can lead to the appropriate number of fractional order as well. Furthermore, through the fractional order analysis, the system can reach the sliding mode surface in a finite time. And the theoretical considerations are verified by numerical simulation. The performance of the AFTSMC and TSMC strategies is tested by computer simulations. And the comparison simulation results show that the AFTSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes. Moreover, AFTSMC obtains a faster dynamical response, smaller steady-state error rate and lower overshoot.

Planar maneuvering control of underwater snake robots using virtual holonomic constraints.

PubMed

Kohl, Anna M; Kelasidi, Eleni; Mohammadi, Alireza; Maggiore, Manfredi; Pettersen, Kristin Y

2016-11-24

This paper investigates the problem of planar maneuvering control for bio-inspired underwater snake robots that are exposed to unknown ocean currents. The control objective is to make a neutrally buoyant snake robot which is subject to hydrodynamic forces and ocean currents converge to a desired planar path and traverse the path with a desired velocity. The proposed feedback control strategy enforces virtual constraints which encode biologically inspired gaits on the snake robot configuration. The virtual constraints, parametrized by states of dynamic compensators, are used to regulate the orientation and forward speed of the snake robot. A two-state ocean current observer based on relative velocity sensors is proposed. It enables the robot to follow the path in the presence of unknown constant ocean currents. The efficacy of the proposed control algorithm for several biologically inspired gaits is verified both in simulations for different path geometries and in experiments.

Effects of Flood Control Strategies on Flood Resilience Under Sociohydrological Disturbances

NASA Astrophysics Data System (ADS)

Sung, Kyungmin; Jeong, Hanseok; Sangwan, Nikhil; Yu, David J.

2018-04-01

A community capacity to cope with flood hazards, or community flood resilience, emerges from the interplay of hydrological and social processes. This interplay can be significantly influenced by the flood control strategy adopted by a society, i.e., how a society sets its desired flood protection level and strives to achieve this goal. And this interplay can be further complicated by rising land-sea level differences, seasonal water level fluctuations, and economic change. But not much research has been done on how various forms of flood control strategies affect human-flood interactions under these disturbances and therefore flood resilience in the long run. The current study is an effort to address these issues by developing a conceptual model of human-flood interaction mediated by flood control strategies. Our model extends the existing model of Yu et al. (2017), who investigated the flood resilience of a community-based flood protection system in coastal Bangladesh. The major extensions made in this study are inclusions of various forms of flood control strategies (both adaptive and nonadaptive ones), the challenge of rising land-sea level differences, and various high tide level scenarios generated from modifying the statistical variances and averages. Our results show that adaptive forms of flood control strategies tend to outperform nonadaptive ones for maintaining the model community's flood protection system. Adaptive strategies that dynamically adjust target flood protection levels through close monitoring of flood damages and social memories of flood risk can help the model community deal with various disturbances.

Evaluation of a cochlear-implant processing strategy incorporating phantom stimulation and asymmetric pulses

PubMed Central

Monstrey, Jolijn; Deeks, John M.; Macherey, Olivier

2014-01-01

Objective To evaluate a speech-processing strategy in which the lowest frequency channel is conveyed using an asymmetric pulse shape and “phantom stimulation”, where current is injected into one intra-cochlear electrode and where the return current is shared between an intra-cochlear and an extra-cochlear electrode. This strategy is expected to provide more selective excitation of the cochlear apex, compared to a standard strategy where the lowest-frequency channel is conveyed by symmetric pulses in monopolar mode. In both strategies all other channels were conveyed by monopolar stimulation. Design Within-subjects comparison between the two strategies. Four experiments: (1) discrimination between the strategies, controlling for loudness differences, (2) consonant identification, (3) recognition of lowpass-filtered sentences in quiet, (4) sentence recognition in the presence of a competing speaker. Study sample Eight users of the Advanced Bionics CII/Hi-Res 90k cochlear implant. Results Listeners could easily discriminate between the two strategies but no consistent differences in performance were observed. Conclusions The proposed method does not improve speech perception, at least in the short term. PMID:25358027

Evaluation of a cochlear-implant processing strategy incorporating phantom stimulation and asymmetric pulses.

PubMed

Carlyon, Robert P; Monstrey, Jolijn; Deeks, John M; Macherey, Olivier

2014-12-01

To evaluate a speech-processing strategy in which the lowest frequency channel is conveyed using an asymmetric pulse shape and "phantom stimulation", where current is injected into one intra-cochlear electrode and where the return current is shared between an intra-cochlear and an extra-cochlear electrode. This strategy is expected to provide more selective excitation of the cochlear apex, compared to a standard strategy where the lowest-frequency channel is conveyed by symmetric pulses in monopolar mode. In both strategies all other channels were conveyed by monopolar stimulation. Within-subjects comparison between the two strategies. Four experiments: (1) discrimination between the strategies, controlling for loudness differences, (2) consonant identification, (3) recognition of lowpass-filtered sentences in quiet, (4) sentence recognition in the presence of a competing speaker. Eight users of the Advanced Bionics CII/Hi-Res 90k cochlear implant. Listeners could easily discriminate between the two strategies but no consistent differences in performance were observed. The proposed method does not improve speech perception, at least in the short term.

Reading Time Allocation Strategies and Working Memory Using Rapid Serial Visual Presentation

ERIC Educational Resources Information Center

Busler, Jessica N.; Lazarte, Alejandro A.

2017-01-01

Rapid serial visual presentation (RSVP) is a useful method for controlling the timing of text presentations and studying how readers' characteristics, such as working memory (WM) and reading strategies for time allocation, influence text recall. In the current study, a modified version of RSVP (Moving Window RSVP [MW-RSVP]) was used to induce…

The Effect of Reflective Science Journal Writing on Students' Self-Regulated Learning Strategies

ERIC Educational Resources Information Center

Al-Rawahi, Nawar M.; Al-Balushi, Sulaiman M.

2015-01-01

The current study investigates the effectiveness of grade-ten students' reflective science journal writing on their self-regulated learning strategies. We used a pre-post control group quasi-experimental design. The sample consisted of 62 tenth-grade students (15 years old) in Oman, comprising 32 students in the experimental group and 30 students…

Structural and process factors affecting the implementation of antimicrobial resistance prevention and control strategies in U.S. hospitals.

PubMed

Chou, Ann F; Yano, Elizabeth M; McCoy, Kimberly D; Willis, Deanna R; Doebbeling, Bradley N

2008-01-01

To address increases in the incidence of infection with antimicrobial-resistant pathogens, the National Foundation for Infectious Diseases and Centers for Disease Control and Prevention proposed two sets of strategies to (a) optimize antibiotic use and (b) prevent the spread of antimicrobial resistance and control transmission. However, little is known about the implementation of these strategies. Our objective is to explore organizational structural and process factors that facilitate the implementation of National Foundation for Infectious Diseases/Centers for Disease Control and Prevention strategies in U.S. hospitals. We surveyed 448 infection control professionals from a national sample of hospitals. Clinically anchored in the Donabedian model that defines quality in terms of structural and process factors, with the structural domain further informed by a contingency approach, we modeled the degree to which National Foundation for Infectious Diseases and Centers for Disease Control and Prevention strategies were implemented as a function of formalization and standardization of protocols, centralization of decision-making hierarchy, information technology capabilities, culture, communication mechanisms, and interdepartmental coordination, controlling for hospital characteristics. Formalization, standardization, centralization, institutional culture, provider-management communication, and information technology use were associated with optimal antibiotic use and enhanced implementation of strategies that prevent and control antimicrobial resistance spread (all p < .001). However, interdepartmental coordination for patient care was inversely related with antibiotic use in contrast to antimicrobial resistance spread prevention and control (p < .0001). Formalization and standardization may eliminate staff role conflict, whereas centralized authority may minimize ambiguity. Culture and communication likely promote internal trust, whereas information technology use helps integrate and support these organizational processes. These findings suggest concrete strategies for evaluating current capabilities to implement effective practices and foster and sustain a culture of patient safety.

Controlling heat and particle currents in nanodevices by quantum observation

NASA Astrophysics Data System (ADS)

Biele, Robert; Rodríguez-Rosario, César A.; Frauenheim, Thomas; Rubio, Angel

2017-07-01

We demonstrate that in a standard thermo-electric nanodevice the current and heat flows are not only dictated by the temperature and potential gradient, but also by the external action of a local quantum observer that controls the coherence of the device. Depending on how and where the observation takes place, the direction of heat and particle currents can be independently controlled. In fact, we show that the current and heat flow in a quantum material can go against the natural temperature and voltage gradients. Dynamical quantum observation offers new possibilities for the control of quantum transport far beyond classical thermal reservoirs. Through the concept of local projections, we illustrate how we can create and directionality control the injection of currents (electronic and heat) in nanodevices. This scheme provides novel strategies to construct quantum devices with application in thermoelectrics, spintronic injection, phononics, and sensing among others. In particular, highly efficient and selective spin injection might be achieved by local spin projection techniques.

Improved control strategy for wind-powered refrigerated storage of apples

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

Baldwin, J.D.C.

1979-01-01

The need for an improved control strategy for the operation of a wind-powered refrigeration system for the storage of apples was investigated. The results are applicable to other systems which employ intermittently available power sources, battery and thermal storage, and an auxiliary, direct current power supply. Tests were conducted on the wind-powered refrigeration system at the Virginia Polytechnic Institute and State University Horticulture Research Farm in Blacksburg, Virginia. Tests were conducted on the individual components of the system. In situ windmill performance was also conducted. The results of these tests have been presented. An improved control strategy was developed tomore » improve the utilization of available wind energy and to reduce the need for electrical energy from an external source while maintaining an adequate apple storage environment.« less

Gender-Differentiated Parenting Revisited: Meta-Analysis Reveals Very Few Differences in Parental Control of Boys and Girls.

PubMed

Endendijk, Joyce J; Groeneveld, Marleen G; Bakermans-Kranenburg, Marian J; Mesman, Judi

2016-01-01

Although various theories describe mechanisms leading to differential parenting of boys and girls, there is no consensus about the extent to which parents do treat their sons and daughters differently. The last meta-analyses on the subject were conducted more than fifteen years ago, and changes in gender-specific child rearing in the past decade are quite plausible. In the current set of meta-analyses, based on 126 observational studies (15,034 families), we examined mothers' and fathers' differential use of autonomy-supportive and controlling strategies with boys and girls, and the role of moderators related to the decade in which the study was conducted, the observational context, and sample characteristics. Databases of Web of Science, ERIC, PsychInfo, Online Contents, Picarta, and Proquest were searched for studies examining differences in observed parental control of boys and girls between the ages of 0 and 18 years. Few differences were found in parents' use of control with boys and girls. Parents were slightly more controlling with boys than with girls, but the effect size was negligible (d = 0.08). The effect was larger, but still small, in normative groups and in samples with younger children. No overall effect for gender-differentiated autonomy-supportive strategies was found (d = 0.03). A significant effect of time emerged: studies published in the 1970s and 1980s reported more autonomy-supportive strategies with boys than toward girls, but from 1990 onwards parents showed somewhat more autonomy-supportive strategies with girls than toward boys. Taking into account parents' gender stereotypes might uncover subgroups of families where gender-differentiated control is salient, but based on our systematic review of the currently available large data base we conclude that in general the differences between parenting of boys versus girls are minimal.

Enhanced pid vs model predictive control applied to bldc motor

NASA Astrophysics Data System (ADS)

Gaya, M. S.; Muhammad, Auwal; Aliyu Abdulkadir, Rabiu; Salim, S. N. S.; Madugu, I. S.; Tijjani, Aminu; Aminu Yusuf, Lukman; Dauda Umar, Ibrahim; Khairi, M. T. M.

2018-01-01

BrushLess Direct Current (BLDC) motor is a multivariable and highly complex nonlinear system. Variation of internal parameter values with environment or reference signal increases the difficulty in controlling the BLDC effectively. Advanced control strategies (like model predictive control) often have to be integrated to satisfy the control desires. Enhancing or proper tuning of a conventional algorithm results in achieving the desired performance. This paper presents a performance comparison of Enhanced PID and Model Predictive Control (MPC) applied to brushless direct current motor. The simulation results demonstrated that the PSO-PID is slightly better than the PID and MPC in tracking the trajectory of the reference signal. The proposed scheme could be useful algorithms for the system.

An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage

PubMed Central

Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M. A.

2014-01-01

This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods. PMID:24883374

An optimal control strategy for DC bus voltage regulation in photovoltaic system with battery energy storage.

PubMed

Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M A

2014-01-01

This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

A Generalized Precharging Strategy for Soft Startup Process of the Modular Multilevel Converter-Based HVDC Systems

DOE PAGES

Zhang, Lei; Qin, Jiangchao; Wu, Xiajie; ...

2017-01-01

The modular multilevel converter (MMC) has become one of the most promising converter technologies for medium/high-power applications, specifically for highvoltage direct current (HVDC) transmission systems. One of the technical challenges associated with the operation and control of the MMC-based system is to precharge the submodule (SM) capacitors to their nominal voltage during the startup process. In this paper, considering various SM circuits, a generalized precharging strategy is proposed for the MMC-based systems, which can implement soft stratup from dc or ac side. Furthermore, the proposed precharging strategy can be applicabe for various SM circuits and MMC configurations. The proposed startupmore » strategy does not require extra measurements and/or auxiliary power supplies. The charging current is controlled by adjusting the changing rate of the number of blocked and bypassed SM capacitors. Based on the proposed startup strategy, the startup processes of MMC/MMC-HVDC systems based on various SM circuits are analyzed and a generalized startup procedure for various MMC-HVDC systems is proposed. In addition, the uncontrollable steady-state SM capacitor voltages of various MMC-based systems are analyzed and determined, potentially useful in SM design. Our performance of the proposed strategy for various MMC-HVDC systems is evaluated based on time-domain simulation studies in the PSCAD/EMTDC software environment and experimental results based on a scaled-down prototype.« less

A Generalized Precharging Strategy for Soft Startup Process of the Modular Multilevel Converter-Based HVDC Systems

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

Zhang, Lei; Qin, Jiangchao; Wu, Xiajie

The modular multilevel converter (MMC) has become one of the most promising converter technologies for medium/high-power applications, specifically for highvoltage direct current (HVDC) transmission systems. One of the technical challenges associated with the operation and control of the MMC-based system is to precharge the submodule (SM) capacitors to their nominal voltage during the startup process. In this paper, considering various SM circuits, a generalized precharging strategy is proposed for the MMC-based systems, which can implement soft stratup from dc or ac side. Furthermore, the proposed precharging strategy can be applicabe for various SM circuits and MMC configurations. The proposed startupmore » strategy does not require extra measurements and/or auxiliary power supplies. The charging current is controlled by adjusting the changing rate of the number of blocked and bypassed SM capacitors. Based on the proposed startup strategy, the startup processes of MMC/MMC-HVDC systems based on various SM circuits are analyzed and a generalized startup procedure for various MMC-HVDC systems is proposed. In addition, the uncontrollable steady-state SM capacitor voltages of various MMC-based systems are analyzed and determined, potentially useful in SM design. Our performance of the proposed strategy for various MMC-HVDC systems is evaluated based on time-domain simulation studies in the PSCAD/EMTDC software environment and experimental results based on a scaled-down prototype.« less

Organizational strategies mediate nonverbal memory impairment in obsessive-compulsive disorder.

PubMed

Savage, C R; Baer, L; Keuthen, N J; Brown, H D; Rauch, S L; Jenike, M A

1999-04-01

Previous neuropsychological studies of obsessive-compulsive disorder (OCD) have indicated impaired executive functioning and nonverbal memory. The extent to which impaired executive functioning impacts nonverbal memory has not been established. The current study investigated the mediating effects of organizational strategies used when copying a figure on subsequent nonverbal memory for that figure. We examined neuropsychological performance in 20 unmedicated subjects with OCD and 20 matched normal control subjects. Subjects were administered the Rey-Osterrieth Complex Figure Test (RCFT) and neuropsychological tests assessing various aspects of executive function. OCD subjects differed significantly from healthy control subjects in the organizational strategies used to copy the RCFT figure, and they recalled significantly less information on both immediate and delayed testing. Multiple regression analyses indicated that group differences in immediate percent recall were significantly mediated by copy organizational strategies. Further exploratory analyses indicated that organizational problems in OCD may be related to difficulties shifting mental and/or spatial set. Immediate nonverbal memory problems in OCD subjects were mediated by impaired organizational strategies used during the initial copy of the RCFT figure. Thus, the primary deficit was one affecting executive function, which then had a secondary effect on immediate memory. These findings are consistent with current theories proposing frontal-striatal system dysfunction in OCD.

Development of a Two-Wheel Contingency Mode for the MAP Spacecraft

NASA Technical Reports Server (NTRS)

Starin, Scott R.; ODonnell, James R., Jr.; Bauer, Frank (Technical Monitor)

2002-01-01

The Microwave Anisotropy Probe (MAP) is a follow-on mission to the Cosmic Background Explorer (COBE), and is currently collecting data from its orbit near the second Sun-Earth libration point. Due to limited mass, power, and financial resources, a traditional reliability concept including fully redundant components was not feasible for MAP. Instead, the MAP design employs selective hardware redundancy in tandem with contingency software modes and algorithms to improve the odds of mission success. One direction for such improvement has been the development of a two-wheel backup control strategy. This strategy would allow MAP to position itself for maneuvers and collect science data should one of its three reaction wheels fail. Along with operational considerations, the strategy includes three new control algorithms. These algorithms would use the remaining attitude control actuators-thrusters and two reaction wheels-in ways that achieve control goals while minimizing adverse impacts on the functionality of other subsystems and software.

National plan for prevention, early detection, and cancer control in Peru.

PubMed

Vallejos, Carlos

2013-01-01

Peru currently is executing an ambitious plan for cancer control: its first nationwide program of cancer prevention and cancer control, and the first such program launched in Latin America. The adequate strategies were identified from previous experience developing smaller initiatives and from knowledge of our epidemiology and priorities. The geographic landscape and sociocultural differences, in which inequalities play a significant role in access to quality education and specialized cancer care, are the main challenges to elaborate strategies to diminish our burden of advanced disease. Challenges were not only identified for the poorest people, but for other sectors of the population. With a growing Peruvian economy in a globalized market context, emerging sectors are being exposed to new risk factors for cancer and educational strategies were implemented. The development of the National Plan for Cancer Control was launched involving not only technical efforts by a multidisciplinary team, but also political concertation.

Decentralized Interleaving of Paralleled Dc-Dc Buck Converters: Preprint

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

Johnson, Brian B; Rodriguez, Miguel; Sinha, Mohit

We present a decentralized control strategy that yields switch interleaving among parallel connected dc-dc buck converters without communication. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work represents the first fully decentralized strategy formore » switch interleaving of paralleled dc-dc buck converters.« less

Decentralized Interleaving of Paralleled Dc-Dc Buck Converters

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

Johnson, Brian B; Rodriguez, Miguel; Sinha, Mohit

We present a decentralized control strategy that yields switch interleaving among parallel-connected dc-dc buck converters. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform and no communication between different controllers is needed. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work presents themore » first fully decentralized strategy for switch interleaving in paralleled dc-dc buck converters.« less

Measles: Current Status and Outbreak Control on Campus.

ERIC Educational Resources Information Center

Amler, Robert W.; Orenstein, Walter A.

1984-01-01

The current effort to eliminate measles in the United States has caused record low levels of the disease. This strategy must continue to be applied in order to break the transmission of measles on college campuses through high immunization levels, promotion of rapid reporting of cases, and quick responses to outbreaks. (Author/DF)

Current status of Marek’s disease in the United States & worldwide based on a questionnaire survey

USDA-ARS?s Scientific Manuscript database

A questionnaire was widely distributed in 2011 to estimate the global prevalence of Marek’s disease (MD) and gain a better understanding of current control strategies and future concerns. A total of 112 questionnaires were returned representing 116 countries from sources including national branch s...

'I'm not a smoker…yet': a qualitative study on perceptions of tobacco control in Chinese high schools.

PubMed

Zhao, Xiang; Young, Ross M cD; White, Katherine M

2018-04-20

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. 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. 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. 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. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Process control integration requirements for advanced life support systems applicable to manned space missions

NASA Technical Reports Server (NTRS)

Spurlock, Paul; Spurlock, Jack M.; Evanich, Peggy L.

1991-01-01

An overview of recent developments in process-control technology which might have applications in future advanced life support systems for long-duration space operations is presented. Consideration is given to design criteria related to control system selection and optimization, and process-control interfacing methodology. Attention is also given to current life support system process control strategies, innovative sensors, instrumentation and control, and innovations in process supervision.

Effect of anaerobic soil disinfestation and vermicompost on soilborne phytopathogenic agents under tree-crop nursery conditions

USDA-ARS?s Scientific Manuscript database

Anaerobic soil disinfestation (ASD) is a fumigation-independent management strategy for controlling soilborne pathogens. Walnut nurseries currently employ preplant fumigation to control soilborne phytopathogens and weeds, and may be amenable to use ASD instead. We investigated the potential of ASD a...

Cognitive Strategies for Mentally Handicapped Clients.

ERIC Educational Resources Information Center

Hiebert, Bryan; Malcolm, Doreen

There is a need when working with mentally handicapped people to develop interventions that can be used within a self-control framework. One intervention that has demonstrated success in a self-control context with normally intelligent people is Cognitive Stress Inoculation Training (CSIT). In CSIT clients are taught to recognize current self-talk…

Immunomodulation as a neuroprotective and therapeutic strategy for Parkinson's disease.

PubMed

Olson, Katherine E; Gendelman, Howard E

2016-02-01

While immune control is associated with nigrostriatal neuroprotection for Parkinson's disease, direct cause and effect relationships have not yet been realized, and modulating the immune system for therapeutic gain has been openly debated. Here, we review how innate and adaptive immunity affect disease pathobiology, and how each could be harnessed for treatment. The overarching idea is to employ immunopharmacologics as neuroprotective strategies for disease. The aim of the current work is to review disease-modifying treatments that are currently being developed as neuroprotective strategies for PD in experimental animal models and for human disease translation. The long-term goal of this research is to effectively harness the immune system to slow or prevent PD pathobiology. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Benefits of Peer Collaboration: A Replication with a Delayed Posttest.

PubMed

Fleming, Victoria Manion; Alexander, Joyce M.

2001-10-01

The benefits of peer collaboration on strategy use, metacognitive causal attribution, and recall were supported in an earlier study (Manion & Alexander, 1997). Following that study two primary questions remained: Would the observed benefits last beyond an immediate posttest, and would they last regardless of which strategy the children chose to use? The current investigation explores those questions. Thirty-one fourth-grade students from two public schools in Sydney, Australia, experienced either a peer-collaborative treatment condition or an individual task (control condition). A posttest was conducted 5.5 weeks later. As was the case in the original study, children in the treatment condition outperformed children in the control condition in strategy use, metacognitive understanding of strategy chosen, and recall gain. Benefits also sustained regardless of the strategy children chose to implement on the task. Most importantly, the benefits lasted after a period of over a month. Implications for future research are discussed. Copyright 2001 Academic Press.

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

Control of Taenia solium taeniasis/cysticercosis: The best way forward for sub-Saharan Africa?

PubMed

Gabriël, S; Dorny, P; Mwape, K E; Trevisan, C; Braae, U C; Magnussen, P; Thys, S; Bulaya, C; Phiri, I K; Sikasunge, C S; Makungu, C; Afonso, S; Nicolau, Q; Johansen, M V

2017-01-01

Taenia solium taeniasis/cysticercosis is a neglected parasitic zoonosis with significant economic and public health impacts. Control measures can be broadly grouped into community health education, improvements in hygiene and sanitary conditions, proper meat handling at household and community level, improved standards of meat inspection, pig management, treatment of individual patients and possibly human populations, and treatment and/or vaccination of porcine populations. This manuscript looks critically into currently existing control options and provides suggestions on which (combination of) tools would be most effective in the control of T. solium taeniasis/cysticercosis in sub-Saharan Africa. Field data and disease transmission simulations suggest that implementation of a single intervention control strategy will not lead to a satisfactory reduction of disease morbidity or transmission. A feasible strategy to combat T. solium taeniasis/cysticercosis would include a combination of approaches focussing on both human (health education and treatment) and animal host (management, treatment and vaccination), which can vary for different communities and different geographical locations. Selection of the specific strategy depends on cost-effectiveness analyses based on solid field data, currently unavailable, though urgently needed; as well as on health priorities and resources of the country. A One Health approach involving medical, veterinary, environmental and social sectors is essential for T. solium to be controlled and eventually eliminated. Finally the success of any intervention is largely dependent on the level of societal and political acceptance, commitment and engagement. Copyright © 2016 Elsevier B.V. All rights reserved.

A Contingency in the Rosetta Reaction Control System: Alternative Cruise Trajectory Strategies to Cope with Degraded Delta-V Resources

NASA Technical Reports Server (NTRS)

Bauske, Rainer; Companys, Vincente

2007-01-01

Since August 2006 a pressure transducer of the Rosetta Reaction Control System (RCS) shows anomalous telemetries indicating a possible leak in a pressurant line. The future operation mode of the RCS may be affected by this problem, resulting in performance degradation. The current propellant budget and its future evolution are evaluated to show the possible states w.r.t. the required mission delta-V. Alternative cruise trajectory strategies are analyzed, providing delta-V savings, to compensate for the expected performance loss of the RCS.

Management of impulse control disorders in Parkinson's disease: Controversies and future approaches.

PubMed

Samuel, Michael; Rodriguez-Oroz, Maria; Antonini, Angelo; Brotchie, Jonathan M; Ray Chaudhuri, Kallol; Brown, Richard G; Galpern, Wendy R; Nirenberg, Melissa J; Okun, Michael S; Lang, Anthony E

2015-02-01

Impulse control disorders in Parkinson's disease are a group of impulsive behaviors most often associated with dopaminergic treatment. Presently, there is a lack of high quality evidence available to guide their management. This manuscript reviews current management strategies, before concentrating on the concept of dopamine agonist withdrawal syndrome and its implications for the management of impulse control disorders. Further, we focus on controversies, including the role of more recently available anti-parkinsonian drugs, and potential future approaches involving routes of drug delivery, nonpharmacological treatments (such as cognitive behavioral therapy and deep brain stimulation), and other as yet experimental strategies. © 2015 International Parkinson and Movement Disorder Society.

Impulse Control Disorders in Parkinson’s Disease:Management, Controversies, and Potential Approaches

PubMed Central

Samuel, M; Rodriguez-Oroz, M; Antonini, A; Brotchie, JM; Ray Chaudhuri, K; Brown, RG; Galpern, WR; Nirenberg, MJ; Okun, MS; Lang, AE

2016-01-01

Impulse control disorders in Parkinson’s disease are a group of impulsive behaviors most often associated with dopaminergic treatment. Presently, there is a lack of high quality evidence available to guide their management. This manuscript reviews current management strategies, before concentrating on the concept of dopamine agonist withdrawal syndrome and its implications for the management of impulse control disorders. Further, we focus on controversies including the role of more recently available anti-parkinsonian drugs, and potential future approaches involving routes of drug delivery, non-pharmacological treatments (such as cognitive behaviour therapy and deep brain stimulation), and other as yet experimental strategies. PMID:25607799

The difference between energy consumption and energy cost: Modelling energy tariff structures for water resource recovery facilities.

PubMed

Aymerich, I; Rieger, L; Sobhani, R; Rosso, D; Corominas, Ll

2015-09-15

The objective of this paper is to demonstrate the importance of incorporating more realistic energy cost models (based on current energy tariff structures) into existing water resource recovery facilities (WRRFs) process models when evaluating technologies and cost-saving control strategies. In this paper, we first introduce a systematic framework to model energy usage at WRRFs and a generalized structure to describe energy tariffs including the most common billing terms. Secondly, this paper introduces a detailed energy cost model based on a Spanish energy tariff structure coupled with a WRRF process model to evaluate several control strategies and provide insights into the selection of the contracted power structure. The results for a 1-year evaluation on a 115,000 population-equivalent WRRF showed monthly cost differences ranging from 7 to 30% when comparing the detailed energy cost model to an average energy price. The evaluation of different aeration control strategies also showed that using average energy prices and neglecting energy tariff structures may lead to biased conclusions when selecting operating strategies or comparing technologies or equipment. The proposed framework demonstrated that for cost minimization, control strategies should be paired with a specific optimal contracted power. Hence, the design of operational and control strategies must take into account the local energy tariff. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adaptive fractional order sliding mode control for Boost converter in the Battery/Supercapacitor HESS.

PubMed

Wang, Jianlin; Xu, Dan; Zhou, Huan; Zhou, Tao

2018-01-01

In this paper, an adaptive fractional order sliding mode control (AFSMC) scheme is designed for the current tracking control of the Boost-type converter in a Battery/Supercapacitor hybrid energy storage system (HESS). In order to stabilize the current, the adaptation rules based on state-observer and Lyapunov function are being designed. A fractional order sliding surface function is defined based on the tracking current error and adaptive rules. Furthermore, through fractional order analysis, the stability of the fractional order control system is proven, and the value of the fractional order (λ) is being investigated. In addition, the effectiveness of the proposed AFSMC strategy is being verified by numerical simulations. The advantages of good transient response and robustness to uncertainty are being indicated by this design, when compared with a conventional integer order sliding mode control system.

Hall-Effect Based Semi-Fast AC On-Board Charging Equipment for Electric Vehicles

PubMed Central

Milanés-Montero, María Isabel; Gallardo-Lozano, Javier; Romero-Cadaval, Enrique; González-Romera, Eva

2011-01-01

The expected increase in the penetration of electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) will produce unbalanced conditions, reactive power consumption and current harmonics drawn by the battery charging equipment, causing a great impact on the power quality of the future smart grid. A single-phase semi-fast electric vehicle battery charger is proposed in this paper. This ac on-board charging equipment can operate in grid-to-vehicle (G2V) mode, and also in vehicle-to-grid (V2G) mode, transferring the battery energy to the grid when the vehicle is parked. The charger is controlled with a Perfect Harmonic Cancellation (PHC) strategy, contributing to improve the grid power quality, since the current demanded or injected has no harmonic content and a high power factor. Hall-effect current and voltage transducers have been used in the sensor stage to carry out this control strategy. Experimental results with a laboratory prototype are presented. PMID:22163697

Hall-effect based semi-fast AC on-board charging equipment for electric vehicles.

PubMed

Milanés-Montero, María Isabel; Gallardo-Lozano, Javier; Romero-Cadaval, Enrique; González-Romera, Eva

2011-01-01

The expected increase in the penetration of electric vehicles (EV) and plug-in hybrid electric vehicles (PHEV) will produce unbalanced conditions, reactive power consumption and current harmonics drawn by the battery charging equipment, causing a great impact on the power quality of the future smart grid. A single-phase semi-fast electric vehicle battery charger is proposed in this paper. This ac on-board charging equipment can operate in grid-to-vehicle (G2V) mode, and also in vehicle-to-grid (V2G) mode, transferring the battery energy to the grid when the vehicle is parked. The charger is controlled with a Perfect Harmonic Cancellation (PHC) strategy, contributing to improve the grid power quality, since the current demanded or injected has no harmonic content and a high power factor. Hall-effect current and voltage transducers have been used in the sensor stage to carry out this control strategy. Experimental results with a laboratory prototype are presented.

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

Kimmel, Gregory; Sadovskyy, Ivan A.; Glatz, Andreas

For many technological applications of superconductors the performance of a material is determined by the highest current it can carry losslessly-the critical current. In turn, the critical current can be controlled by adding nonsuperconducting defects in the superconductor matrix. Here we report on systematic comparison of different local and global optimization strategies to predict optimal structures of pinning centers leading to the highest possible critical currents. We demonstrate performance of these methods for a superconductor with randomly placed spherical, elliptical, and columnar defects.

An Economic Evaluation of Preclinical Testing Strategies Compared to the Compulsory Scrapie Flock Scheme in the Control of Classical Scrapie

PubMed Central

Hawkins, Neil; Houston, Fiona; Fryer, Helen; Kao, Rowland

2012-01-01

Cost-benefit is rarely combined with nonlinear dynamic models when evaluating control options for infectious diseases. The current strategy for scrapie in Great Britain requires that all genetically susceptible livestock in affected flocks be culled (Compulsory Scrapie Flock Scheme or CSFS). However, this results in the removal of many healthy sheep, and a recently developed pre-clinical test for scrapie now offers a strategy based on disease detection. We explore the flock level cost-effectiveness of scrapie control using a deterministic transmission model and industry estimates of costs associated with genotype testing, pre-clinical tests and the value of a sheep culled. Benefit was measured in terms of the reduction in the number of infected sheep sold on, compared to a baseline strategy of doing nothing, using Incremental Cost Effectiveness analysis to compare across strategies. As market data was not available for pre-clinical testing, a threshold analysis was used to set a unit-cost giving equal costs for CSFS and multiple pre-clinical testing (MT, one test each year for three consecutive years). Assuming a 40% within-flock proportion of susceptible genotypes and a test sensitivity of 90%, a single test (ST) was cheaper but less effective than either the CSFS or MT strategies (30 infected-sales-averted over the lifetime of the average epidemic). The MT strategy was slightly less effective than the CSFS and would be a dominated strategy unless preclinical testing was cheaper than the threshold price of £6.28, but may be appropriate for flocks with particularly valuable livestock. Though the ST is not currently recommended, the proportion of susceptible genotypes in the national flock is likely to continue to decrease; this may eventually make it a cost-effective alternative to the MT or CSFS. PMID:22412943

Upper-Limb Robotic Exoskeletons for Neurorehabilitation: A Review on Control Strategies.

PubMed

Proietti, Tommaso; Crocher, Vincent; Roby-Brami, Agnes; Jarrasse, Nathanael

2016-01-01

Since the late 1990s, there has been a burst of research on robotic devices for poststroke rehabilitation. Robot-mediated therapy produced improvements on recovery of motor capacity; however, so far, the use of robots has not shown qualitative benefit over classical therapist-led training sessions, performed on the same quantity of movements. Multidegree-of-freedom robots, like the modern upper-limb exoskeletons, enable a distributed interaction on the whole assisted limb and can exploit a large amount of sensory feedback data, potentially providing new capabilities within standard rehabilitation sessions. Surprisingly, most publications in the field of exoskeletons focused only on mechatronic design of the devices, while little details were given to the control aspects. On the contrary, we believe a paramount aspect for robots potentiality lies on the control side. Therefore, the aim of this review is to provide a taxonomy of currently available control strategies for exoskeletons for neurorehabilitation, in order to formulate appropriate questions toward the development of innovative and improved control strategies.

Integrated Pest Management of Coffee Berry Borer: Strategies from Latin America that Could Be Useful for Coffee Farmers in Hawaii.

PubMed

Aristizábal, Luis F; Bustillo, Alex E; Arthurs, Steven P

2016-02-03

The coffee berry borer (CBB), Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae) is the primary arthropod pest of coffee plantations worldwide. Since its detection in Hawaii (September 2010), coffee growers are facing financial losses due to reduced quality of coffee yields. Several control strategies that include cultural practices, biological control agents (parasitoids), chemical and microbial insecticides (entomopathogenic fungi), and a range of post-harvest sanitation practices have been conducted to manage CBB around the world. In addition, sampling methods including the use of alcohol based traps for monitoring CBB populations have been implemented in some coffee producing countries in Latin America. It is currently unclear which combination of CBB control strategies is optimal under economical, environmental, and sociocultural conditions of Hawaii. This review discusses components of an integrated pest management program for CBB. We focus on practical approaches to provide guidance to coffee farmers in Hawaii. Experiences of integrated pest management (IPM) of CBB learned from Latin America over the past 25 years may be relevant for establishing strategies of control that may fit under Hawaiian coffee farmers' conditions.

Human-tracking strategies for a six-legged rescue robot based on distance and view

NASA Astrophysics Data System (ADS)

Pan, Yang; Gao, Feng; Qi, Chenkun; Chai, Xun

2016-03-01

Human tracking is an important issue for intelligent robotic control and can be used in many scenarios, such as robotic services and human-robot cooperation. Most of current human-tracking methods are targeted for mobile/tracked robots, but few of them can be used for legged robots. Two novel human-tracking strategies, view priority strategy and distance priority strategy, are proposed specially for legged robots, which enable them to track humans in various complex terrains. View priority strategy focuses on keeping humans in its view angle arrange with priority, while its counterpart, distance priority strategy, focuses on keeping human at a reasonable distance with priority. To evaluate these strategies, two indexes(average and minimum tracking capability) are defined. With the help of these indexes, the view priority strategy shows advantages compared with distance priority strategy. The optimization is done in terms of these indexes, which let the robot has maximum tracking capability. The simulation results show that the robot can track humans with different curves like square, circular, sine and screw paths. Two novel control strategies are proposed which specially concerning legged robot characteristics to solve human tracking problems more efficiently in rescue circumstances.

Managing work and family: Do control strategies help?

PubMed

Versey, H Shellae

2015-11-01

How can we effectively manage competing obligations from work and family without becoming overwhelmed? This question inspires the current study by examining control strategies that may facilitate better work-life balance, with a specific focus on the role of lowered aspirations and positive reappraisals, attitudes that underlie adaptive coping behaviors. Data from the Midlife in the United States Survey (MIDUS II) were used to explore the relationship between negative spillover, control strategies, and well-being among full-time working men and women (N = 2,091). In this nationally representative sample, findings indicate that while positive reappraisals function as a protective buffer, lowering aspirations exacerbate the relationship between work-family spillover and well-being, with moderating effects stronger among women. This study extends prior research tying work-life conflict to health and mental health, and suggests further investigation is needed to consider types of resources that may be effective coping strategies in balancing work and family. (c) 2015 APA, all rights reserved).

Examining cognitive emotion regulation in frontal lobe patients: The mediating role of response inhibition.

PubMed

Falquez, Rosalux; Dinu-Biringer, Ramona; Stopsack, Malte; Arens, Elisabeth A; Wick, Wolfgang; Barnow, Sven

2015-01-01

Previous investigations have demonstrated the relationship between inhibitory deficits and maladaptive emotion regulation. Although several neuropsychological studies show that frontal lobe damage can lead to extreme inhibition impairments, there have been no investigations regarding the influence of frontal lobe damage and related inhibition impairments on the use of maladaptive strategies. The goal of the current study was to examine the impact of executive functions impairments due to frontal lobe damage on cognitive emotion regulation. Fifteen patients with frontal lobe damage were compared to twenty-two healthy controls on their reported use of maladaptive strategies. The effect of behavioral inhibition deficits among the frontal lobe damage group was examined. Patients reflected a heightened use of maladaptive strategies compared to healthy controls, significantly mediated by Go/NoGo task errors, which are an indicator for response inhibition deficits. Results suggest that a heightened use of maladaptive strategies by patients relies to a strong extent on their impaired impulse control, highlighting the complex interplay between executive functions and emotional regulation.

DEVELOPMENT OF AN ANTIFOAM TRACKING SYSTEM AS AN OPTION TO SUPPORT THE MELTER OFF-GAS FLAMMABILITY CONTROL STRATEGY AT THE DWPF

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

Edwards, T.; Lambert, D.

The Savannah River National Laboratory (SRNL) has been working with the Savannah River Remediation (SRR) Defense Waste Processing Facility (DWPF) in the development and implementation of an additional strategy for confidently satisfying the flammability controls for DWPF’s melter operation. An initial strategy for implementing the operational constraints associated with flammability control in DWPF was based upon an analytically determined carbon concentration from antifoam. Due to the conservative error structure associated with the analytical approach, its implementation has significantly reduced the operating window for processing and has led to recurrent Slurry Mix Evaporator (SME) and Melter Feed Tank (MFT) remediation. Tomore » address the adverse operating impact of the current implementation strategy, SRR issued a Technical Task Request (TTR) to SRNL requesting the development and documentation of an alternate strategy for evaluating the carbon contribution from antifoam. The proposed strategy presented in this report was developed under the guidance of a Task Technical and Quality Assurance Plan (TTQAP) and involves calculating the carbon concentration from antifoam based upon the actual mass of antifoam added to the process assuming 100% retention. The mass of antifoam in the Additive Mix Feed Tank (AMFT), in the Sludge Receipt and Adjustment Tank (SRAT), and in the SME is tracked by mass balance as part of this strategy. As these quantities are monitored, the random and bias uncertainties affecting their values are also maintained and accounted for. This report documents: 1) the development of an alternate implementation strategy and associated equations describing the carbon concentration from antifoam in each SME batch derived from the actual amount of antifoam introduced into the AMFT, SRAT, and SME during the processing of the batch. 2) the equations and error structure for incorporating the proposed strategy into melter off-gas flammability assessments. Sample calculations of the system are also included in this report. Please note that the system developed and documented in this report is intended as an alternative to the current, analytically-driven system being utilized by DWPF; the proposed system is not intended to eliminate the current system. Also note that the system developed in this report to track antifoam mass in the AMFT, SRAT, and SME will be applicable beyond just Sludge Batch 8. While the model used to determine acceptability of the SME product with respect to melter off-gas flammability controls must be reassessed for each change in sludge batch, the antifoam mass tracking methodology is independent of sludge batch composition and as such will be transferable to future sludge batches.« less

Strategies to diagnose and control microbial souring in natural gas storage reservoirs and produced water systems

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

Morris, E.A.; Derr, R.M.; Pope, D.H.

1995-12-31

Hydrogen sulfide production (souring) in natural gas storage reservoirs and produced water systems is a safety and environmental problem that can lead to operational shutdown when local hydrogen sulfide standards are exceeded. Systems affected by microbial souring have historically been treated using biocides that target the general microbial community. However, requirements for more environmentally friendly solutions have led to treatment strategies in which sulfide production can be controlled with minimal impact to the system and environment. Some of these strategies are based on microbial and/or nutritional augmentation of the sour environment. Through research sponsored by the Gas Research Institute (GRI)more » in Chicago, Illinois, methods have been developed for early detection of microbial souring in natural gas storage reservoirs, and a variety of mitigation strategies have been evaluated. The effectiveness of traditional biocide treatment in gas storage reservoirs was shown to depend heavily on the methods by which the chemical is applied. An innovative strategy using nitrate was tested and proved ideal for produced water and wastewater systems. Another strategy using elemental iodine was effective for sulfide control in evaporation ponds and is currently being tested in microbially sour natural gas storage wells.« less

Optimal robust control strategy of a solid oxide fuel cell system

NASA Astrophysics Data System (ADS)

Wu, Xiaojuan; Gao, Danhui

2018-01-01

Optimal control can ensure system safe operation with a high efficiency. However, only a few papers discuss optimal control strategies for solid oxide fuel cell (SOFC) systems. Moreover, the existed methods ignore the impact of parameter uncertainty on system instantaneous performance. In real SOFC systems, several parameters may vary with the variation of operation conditions and can not be identified exactly, such as load current. Therefore, a robust optimal control strategy is proposed, which involves three parts: a SOFC model with parameter uncertainty, a robust optimizer and robust controllers. During the model building process, boundaries of the uncertain parameter are extracted based on Monte Carlo algorithm. To achieve the maximum efficiency, a two-space particle swarm optimization approach is employed to obtain optimal operating points, which are used as the set points of the controllers. To ensure the SOFC safe operation, two feed-forward controllers and a higher-order robust sliding mode controller are presented to control fuel utilization ratio, air excess ratio and stack temperature afterwards. The results show the proposed optimal robust control method can maintain the SOFC system safe operation with a maximum efficiency under load and uncertainty variations.

Stay Smart: Lost Weight--Childhood Obesity and Health Education

ERIC Educational Resources Information Center

Kosa-Postl, Linda

2006-01-01

Prevention is the key strategy for controlling the current epidemic levels of childhood obesity. Current statistics show that obesity has more than doubled for preschool children aged 2-5 years and adolescents aged 12-19 years, and it has more than tripled for children aged 6-11 years. It is generally recognized that nutrition education for the…

Cholera in the 21st century.

PubMed

Charles, Richelle C; Ryan, Edward T

2011-10-01

This review will focus on recent advances in our understanding of biologic and environmental factors that shape current cholera outbreaks, advances in our understanding of host-pathogen interactions during cholera, and recent evolution of current treatment and cholera prevention strategies. New research studies have improved our understanding of a number of dynamic factors that shape the ecology of Vibrio cholerae and influence its transmission, including the role of lytic bacteriophage, biofilm formation, a hyperinfectious state of human-passaged V. cholerae, and the impact of severe weather events. Provision of safe water and improved sanitation continue to be the mainstays of preventing cholera transmission; however, the role of cholera vaccination as a control measure in both endemic and epidemic settings is evolving. Recent advances in our understanding of long-lived protective immunity after natural infection may aid in the global efforts to control cholera. Improved understanding of factors associated with protective immunity and dynamic factors associated with cholera outbreaks may lead to improved control and prevention strategies for cholera.

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

Field Evaluations of Systemic Insecticides for Control of Anoplophora glabripennis (Coleoptera: Cerambycidae) in China

Treesearch

Therese M. Poland; Robert A. Haack; Toby R. Petrice; Deborah L. Miller; Leah S. Bauer; Ruitong Gao

2006-01-01

Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), a pest native to China and Korea, was discovered in North America in 1996. Currently, the only reliable strategy available for eradication and control is to cut and chip all infested trees. We evaluated various doses of the systemic insecticides azadirachtin, emamectin benzoate,...

Chemosterilants for Control of Insects and Insect Vectors of Disease.

PubMed

Baxter, Richard H G

2016-10-01

Both historically and at present, vector control is the most generally effective means of controlling malaria transmission. Insecticides are the predominant method of vector control, but the sterile insect technique (SIT) is a complementary strategy with a successful track record in both agricultural and public health sectors. Strategies of genetic and radiation-induced sterilization of Anopheles have to date been limited by logistical and/or regulatory hurdles. A safe and effective mosquito chemosterilant would therefore be of major utility to future deployment of SIT for malaria control. Here we review the prior and current use of chemosterilants in SIT, and assess the potential for future research. Recent genomic and proteomic studies reveal opportunities for specific targeting of seminal fluid proteins, and the capacity to interfere with sperm motility and storage in the female.

New repellent effective against African malaria mosquito Anopheles gambiae: implications for vector control.

PubMed

Hodson, C N; Yu, Y; Plettner, E; Roitberg, B D

2016-12-01

Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is a vector for Plasmodium, the causative agent of malaria. Current control strategies to reduce the impact of malaria focus on reducing the frequency of mosquito attacks on humans, thereby decreasing Plasmodium transmission. A need for new repellents effective against Anopheles mosquitoes has arisen because of changes in vector behaviour as a result of control strategies and concern over the health impacts of current repellents. The response of A. gambiae to potential repellents was investigated through an electroantennogram screen and the most promising of these candidates (1-allyloxy-4-propoxybenzene, 3c{3,6}) chosen for behavioural testing. An assay to evaluate the blood-host seeking behaviour of A. gambiae towards a simulated host protected with this repellent was then performed. The compound 3c{3,6} was shown to be an effective repellent, causing mosquitoes to reduce their contact with a simulated blood-host and probe less at the host odour. Thus, 3c{3,6} may be an effective repellent for the control of A. gambiae. © 2016 The Royal Entomological Society.

Control of Grid Connected Photovoltaic System Using Three-Level T-Type Inverter

NASA Astrophysics Data System (ADS)

Zorig, Abdelmalik; Belkeiri, Mohammed; Barkat, Said; Rabhi, Abdelhamid

2016-08-01

Three-level T-Type inverter (3LT2I) topology has numerous advantageous compared to three-level neutral-point-clamped (NPC) inverter. The main benefits of 3LT2I inverter are the efficiency, inverter cost, switching losses, and the quality of output voltage waveforms. In this paper, a photovoltaic distributed generation system based on dual-stage topology of DC-DC boost converter and 3LT2I is introduced. To that end, a decoupling control strategy of 3LT2I is proposed to control the current injected into the grid, reactive power compensation, and DC-link voltage. The resulting system is able to extract the maximum power from photovoltaic generator, to achieve sinusoidal grid currents, and to ensure reactive power compensation. The voltage-balancing control of two split DC capacitors of the 3LT2I is achieved using three-level space vector modulation with balancing strategy based on the effective use of the redundant switching states of the inverter voltage vectors. The proposed system performance is investigated at different operating conditions.

Naval Operations Concept: Implementing the Maritime Strategy

DTIC Science & Technology

2010-01-01

Naval Operations Concept 2010 Implementing The Maritime Strategy Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden...Directorate for Information Operations and Reports , 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that...display a currently valid OMB control number. 1. REPORT DATE 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND

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.

Development of robust building energy demand-side control strategy under uncertainty

NASA Astrophysics Data System (ADS)

Kim, Sean Hay

The potential of carbon emission regulations applied to an individual building will encourage building owners to purchase utility-provided green power or to employ onsite renewable energy generation. As both cases are based on intermittent renewable energy sources, demand side control is a fundamental precondition for maximizing the effectiveness of using renewable energy sources. Such control leads to a reduction in peak demand and/or in energy demand variability, therefore, such reduction in the demand profile eventually enhances the efficiency of an erratic supply of renewable energy. The combined operation of active thermal energy storage and passive building thermal mass has shown substantial improvement in demand-side control performance when compared to current state-of-the-art demand-side control measures. Specifically, "model-based" optimal control for this operation has the potential to significantly increase performance and bring economic advantages. However, due to the uncertainty in certain operating conditions in the field its control effectiveness could be diminished and/or seriously damaged, which results in poor performance. This dissertation pursues improvements of current demand-side controls under uncertainty by proposing a robust supervisory demand-side control strategy that is designed to be immune from uncertainty and perform consistently under uncertain conditions. Uniqueness and superiority of the proposed robust demand-side controls are found as below: a. It is developed based on fundamental studies about uncertainty and a systematic approach to uncertainty analysis. b. It reduces variability of performance under varied conditions, and thus avoids the worst case scenario. c. It is reactive in cases of critical "discrepancies" observed caused by the unpredictable uncertainty that typically scenario uncertainty imposes, and thus it increases control efficiency. This is obtainable by means of i) multi-source composition of weather forecasts including both historical archive and online sources and ii) adaptive Multiple model-based controls (MMC) to mitigate detrimental impacts of varying scenario uncertainties. The proposed robust demand-side control strategy verifies its outstanding demand-side control performance in varied and non-indigenous conditions compared to the existing control strategies including deterministic optimal controls. This result reemphasizes importance of the demand-side control for a building in the global carbon economy. It also demonstrates a capability of risk management of the proposed robust demand-side controls in highly uncertain situations, which eventually attains the maximum benefit in both theoretical and practical perspectives.

Rotor Current Control of DFIG for Improving Fault Ride - Through Using a Novel Sliding Mode Control Approach

NASA Astrophysics Data System (ADS)

Cai, Guowei; Liu, Cheng; Yang, Deyou

2013-11-01

The doubly fed induction generators (DFIG) have been recognized as the dominant technology used in wind power generation systems with the rapid development of wind power. However, continuous operation of DFIG may cause a serious wind turbine generators tripping accident, due to destructive over-current in the rotor winding which is caused by the power system fault or inefficient fault ride-through (FRT) strategy. A new rotor current control scheme in the rotor-side converter (RSC) ispresented to enhance FRT capacities of grid-connected DFIG. Due to the strongly nonlinear nature of DFIG and insensitive to DFIG parameter's variations, a novel sliding mode controller was designed. The controller combines extended state observer (ESO) with sliding model variable structure control theory. The simulation is carried out to verify the effectiveness of the proposed control approach under various types of grid disturbances. It is shown that the proposed controller provides enhanced transient features than the classic proportional-integral control. The proposed control method can effectively reduce over-current in the RSC, and the transient pulse value of electromagnetic torque is too large under power grid fault.

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.

Delivering Faster Congestion Feedback with the Mark-Front Strategy

NASA Technical Reports Server (NTRS)

Liu, Chunlei; Jain, Raj

2001-01-01

Computer networks use congestion feedback from the routers and destinations to control the transmission load. Delivering timely congestion feedback is essential to the performance of networks. Reaction to the congestion can be more effective if faster feedback is provided. Current TCP/IP networks use timeout, duplicate Acknowledgement Packets (ACKs) and explicit congestion notification (ECN) to deliver the congestion feedback, each provides a faster feedback than the previous method. In this paper, we propose a markfront strategy that delivers an even faster congestion feedback. With analytical and simulation results, we show that mark-front strategy reduces buffer size requirement, improves link efficiency and provides better fairness among users. Keywords: Explicit Congestion Notification, mark-front, congestion control, buffer size requirement, fairness.

Adaptive fractional order sliding mode control for Boost converter in the Battery/Supercapacitor HESS

PubMed Central

Xu, Dan; Zhou, Huan; Zhou, Tao

2018-01-01

In this paper, an adaptive fractional order sliding mode control (AFSMC) scheme is designed for the current tracking control of the Boost-type converter in a Battery/Supercapacitor hybrid energy storage system (HESS). In order to stabilize the current, the adaptation rules based on state-observer and Lyapunov function are being designed. A fractional order sliding surface function is defined based on the tracking current error and adaptive rules. Furthermore, through fractional order analysis, the stability of the fractional order control system is proven, and the value of the fractional order (λ) is being investigated. In addition, the effectiveness of the proposed AFSMC strategy is being verified by numerical simulations. The advantages of good transient response and robustness to uncertainty are being indicated by this design, when compared with a conventional integer order sliding mode control system. PMID:29702696

A review of wind turbine-oriented active flow control strategies

NASA Astrophysics Data System (ADS)

Aubrun, Sandrine; Leroy, Annie; Devinant, Philippe

2017-10-01

To reduce the levelized cost of energy, the energy production, robustness and lifespan of horizontal axis wind turbines (HAWTs) have to be improved to ensure optimal energy production and operational availability during periods longer than 15-20 years. HAWTs are subject to unsteady wind loads that generate combinations of unsteady mechanical loads with characteristic time scales from seconds to minutes. This can be reduced by controlling the aerodynamic performance of the wind turbine rotors in real time to compensate the overloads. Mitigating load fluctuations and optimizing the aerodynamic performance at higher time scales need the development of fast-response active flow control (AFC) strategies located as close as possible to the torque generation, i.e., directly on the blades. The most conventional actuators currently used in HAWTs are mechanical flaps/tabs (similar to aeronautical accessories), but some more innovative concepts based on fluidic and plasma actuators are very promising since they are devoid of mechanical parts, have a fast response and can be driven in unsteady modes to influence natural instabilities of the flow. In this context, the present paper aims at giving a state-of-the-art review of current research in wind turbine-oriented flow control strategies applied at the blade scale. It provides an overview of research conducted in the last decade dealing with the actuators and devices devoted to developing AFC on rotor blades, focusing on the flow phenomena that they cause and that can lead to aerodynamic load increase or decrease. After providing some general background on wind turbine blade aerodynamics and on the atmospheric flows in which HAWTs operate, the review focuses on flow separation control and circulation control mainly through experimental investigations. It is followed by a discussion about the overall limitations of current studies in the wind energy context, with a focus on a few studies that attempt to provide a global efficiency assessment and wind energy-oriented energy balance.

Infection control strategies for preventing the transmission of meticillin-resistant Staphylococcus aureus (MRSA) in nursing homes for older people.

PubMed

Hughes, Carmel; Smith, Michael; Tunney, Michael; Bradley, Marie C

2011-12-07

Nursing homes for older people provide an environment likely to promote the acquisition and spread of meticillin-resistant Staphylococcus aureus (MRSA), putting residents at increased risk of colonisation and infection. It is recognised that infection prevention and control strategies are important in preventing and controlling MRSA transmission. To determine the effects of infection prevention and control strategies for preventing the transmission of MRSA in nursing homes for older people. We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2011, Issue 2), the Cochrane Wounds Group Specialised Register (searched May 27th, 2011). We also searched Ovid MEDLINE (from 1950 to April Week 2 2011), OVID MEDLINE (In-process and Other Non-Indexed Citations, April 26th 2011) Ovid EMBASE (1980 to 2011 Week 16), EBSCO CINAHL (1982 to April 21st 2011), DARE (1992 to 2011, week 16), Web of Science (1981 to May 2011), and the Health Technology Assessment (HTA) website (1988 to May 2011). Research in progress was sought through Current Clinical Trials (www.controlled-trials.com), Medical Research Council Research portfolio, and HSRPRoj (current USA projects). All randomised and controlled clinical trials, controlled before and after studies and interrupted time series studies of infection prevention and control interventions in nursing homes for older people were eligible for inclusion. Two review authors independently reviewed the results of the searches. Another review author appraised identified papers and undertook data extraction which was checked by a second review author. For this second update only one study was identified, therefore it was not possible to undertake a meta-analysis. A cluster randomised controlled trial in 32 nursing homes evaluated the effect of an infection control education and training programme on MRSA prevalence. The primary outcome was MRSA prevalence in residents and staff, and a change in infection control audit scores which measured adherence to infection control standards. At the end of the 12 month study, there was no change in MRSA prevalence between intervention and control sites, while mean infection control audit scores were significantly higher in the intervention homes compared with control homes. There is a lack of research evaluating the effects on MRSA transmission of infection prevention and control strategies in nursing homes. Rigorous studies should be conducted in nursing homes, to test interventions that have been specifically designed for this unique environment.

Post-Closure Strategy for Use-Restricted Sites on the Nevada National Security Site, Nevada Test and Training Range, and Tonopah Test Range, Nevada

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

Silvas, A. J.

The purpose of this Post-Closure Strategy is to provide a consistent methodology for continual evaluation of post-closure requirements for use-restricted areas on the Nevada National Security Site (NNSS), Nevada Test and Training Range (NTTR), and Tonopah Test Range (TTR) to consolidate, modify, or streamline the program. In addition, this document stipulates the creation of a single consolidated Post-Closure Plan that will detail the current post-closure requirements for all active use restrictions (URs) and outlines its implementation and subsequent revision. This strategy will ensure effective management and control of the post-closure sites. There are currently over 200 URs located on themore » NNSS, NTTR, and TTR. Post-closure requirements were initially established in the Closure Report for each site. In some cases, changes to the post-closure requirements have been implemented through addenda, errata sheets, records of technical change, or letters. Post-closure requirements have been collected from these multiple sources and consolidated into several formats, such as summaries and databases. This structure increases the possibility of inconsistencies and uncertainty. As more URs are established and the post-closure program is expanded, the need for a comprehensive approach for managing the program will increase. Not only should the current requirements be obtainable from a single source that supersedes all previous requirements, but the strategy for modifying the requirements should be standardized. This will enable more effective management of the program into the future. This strategy document and the subsequent comprehensive plan are to be implemented under the assumption that the NNSS and outlying sites will be under the purview of the U.S. Department of Energy, National Nuclear Security Administration for the foreseeable future. This strategy was also developed assuming that regulatory control of the sites remains static. The comprehensive plan is not intended to be a permanent long-term stewardship plan. However, it is intended to clarify requirements and identify components to effectively manage the sites until regulatory requirements are met or management of the site changes. The Environmental Management Program is required to manage these sites until the NNSS Environmental Restoration program is completed, currently planned for 2030. Prior to completion of the Environmental Restoration program, additional planning will be conducted to ensure that long-term stewardship of the sites is maintained. A comprehensive post-closure plan can be transitioned effectively into any future site-wide long-term stewardship program that may be developed. Therefore, the post-closure plan will include current aspects of the post-closure program that are also important aspects of long-term stewardship, including the following: • Management of physical and engineering controls such as fences, signs, and soil covers • Management of institutional and administrative controls such as use restrictions and real estate systems • Management of monitoring and maintenance programs • Management of information related to the sites such as geographic information system data and related documentation The strategy will also allow for periodic review and modification of any aspect of the program to ensure continued effectiveness.« less

Sexually transmitted infections: challenges ahead.

PubMed

Unemo, Magnus; Bradshaw, Catriona S; Hocking, Jane S; de Vries, Henry J C; Francis, Suzanna C; Mabey, David; Marrazzo, Jeanne M; Sonder, Gerard J B; Schwebke, Jane R; Hoornenborg, Elske; Peeling, Rosanna W; Philip, Susan S; Low, Nicola; Fairley, Christopher K

2017-08-01

WHO estimated that nearly 1 million people become infected every day with any of four curable sexually transmitted infections (STIs): chlamydia, gonorrhoea, syphilis, and trichomoniasis. Despite their high global incidence, STIs remain a neglected area of research. In this Commission, we have prioritised five areas that represent particular challenges in STI treatment and control. Chlamydia remains the most commonly diagnosed bacterial STI in high-income countries despite widespread testing recommendations, sensitive and specific non-invasive testing techniques, and cheap effective therapy. We discuss the challenges for chlamydia control and evidence to support a shift from the current focus on infection-based screening to improved management of diagnosed cases and of chlamydial morbidity, such as pelvic inflammatory disease. The emergence and spread of antimicrobial resistance in Neisseria gonorrhoeae is globally recognised. We review current and potential future control and treatment strategies, with a focus on novel antimicrobials. Bacterial vaginosis is the most common vaginal disorder in women, but current treatments are associated with frequent recurrence. Recurrence after treatment might relate to evidence that suggests sexual transmission is integral to the pathogenesis of bacterial vaginosis, which has substantial implications for the development of effective management approaches. STIs disproportionately affect low-income and middle-income countries. We review strategies for case management, focusing on point-of-care tests that hold considerable potential for improving STI control. Lastly, STIs in men who have sex with men have increased since the late 1990s. We discuss the contribution of new biomedical HIV prevention strategies and risk compensation. Overall, this Commission aims to enhance the understanding of some of the key challenges facing the field of STIs, and outlines new approaches to improve the clinical management of STIs and public health. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of a model to simulate infection dynamics of Mycobacterium bovis in cattle herds in the United States

PubMed Central

Smith, Rebecca L.; Schukken, Ynte H.; Lu, Zhao; Mitchell, Rebecca M.; Grohn, Yrjo T.

2013-01-01

Objective To develop a mathematical model to simulate infection dynamics of Mycobacterium bovis in cattle herds in the United States and predict efficacy of the current national control strategy for tuberculosis in cattle. Design Stochastic simulation model. Sample Theoretical cattle herds in the United States. Procedures A model of within-herd M bovis transmission dynamics following introduction of 1 latently infected cow was developed. Frequency- and density-dependent transmission modes and 3 tuberculin-test based culling strategies (no test-based culling, constant (annual) testing with test-based culling, and the current strategy of slaughterhouse detection-based testing and culling) were investigated. Results were evaluated for 3 herd sizes over a 10-year period and validated via simulation of known outbreaks of M bovis infection. Results On the basis of 1,000 simulations (1000 herds each) at replacement rates typical for dairy cattle (0.33/y), median time to detection of M bovis infection in medium-sized herds (276 adult cattle) via slaughterhouse surveillance was 27 months after introduction, and 58% of these herds would spontaneously clear the infection prior to that time. Sixty-two percent of medium-sized herds without intervention and 99% of those managed with constant test-based culling were predicted to clear infection < 10 years after introduction. The model predicted observed outbreaks best for frequency-dependent transmission, and probability of clearance was most sensitive to replacement rate. Conclusions and Clinical Relevance Although modeling indicated the current national control strategy was sufficient for elimination of M bovis infection from dairy herds after detection, slaughterhouse surveillance was not sufficient to detect M bovis infection in all herds and resulted in subjectively delayed detection, compared with the constant testing method. Further research is required to economically optimize this strategy. PMID:23865885

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

Detection and Management of Diabetes in England: Results from the Health Survey for England.

PubMed

Xiao, Mimi; O'Neill, Ciaran

2017-10-01

As part of a control strategy current guidance in the UK recommends more intense surveillance of HbA1C levels among those of South-east Asian or Chinese ethnicity above specified BMI thresholds. The objective of this study was to determine whether disparities in the identification and control of diabetes in England persisted despite these guidelines and assess current strategies in light of these findings. Data were extracted from the 2013 Health Survey for England that included ethnicity, BMI status and HbA1C levels. Descriptive statistics and logistic regression analyses were used to examine relationships among undetected diabetes, poorly controlled diabetes and a range of covariates including ethnicity and BMI. Concentration indices were used to examine the socio-economic gradient in disease detection and control among and between ethnic groups. In regression models that controlled for a range of covariates Asians were found to have a 5% point higher risk of undetected diabetes than Whites. With respect to disease management, Bangladeshis and Pakistanis were found to be at a 28% point and 21% point higher risk of poor disease control respectively than Whites. Concentration indices revealed better disease control among more affluent Whites than poor Whites, no significant pattern between income and disease management was found among Pakistanis and poorer disease control was more evident among more affluent than poorer Bangladeshis. In the UK current guidance recommends practitioners consider testing for diabetes among South-east Asians and Chinese where BMI exceeds 23. Our findings suggest that the risk experienced by Asians in disease detection is independent of BMI and may warrant a more active screening policy than currently recommended. With respect to disease management, our findings suggest that Indians and Pakistanis experience particularly high levels of poor disease control that may also be usefully reflected in guidance.

Control of Visceral Leishmaniasis in Latin America—A Systematic Review

PubMed Central

Romero, Gustavo A. S.; Boelaert, Marleen

2010-01-01

Background While three countries in South Asia decided to eliminate anthroponotic visceral leishmaniasis (VL) by 2015, its control in other regions seems fraught with difficulties. Is there a scope for more effective VL control in the Americas where transmission is zoonotic? We reviewed the evidence on VL control strategies in Latin America—diagnosis, treatment, veterinary interventions, vector control—with respect to entomological and clinical outcomes. Methodology/Principal Findings We searched the electronic databases of MEDLINE, LILACS, and the Cochrane Central Register of Controlled Trials, from 1960 to November 2008 and references of selected articles. Intervention trials as well as observational studies that evaluated control strategies of VL in the Americas were included. While the use of rapid diagnostic tests for VL diagnosis seems well established, there is a striking lack of evidence from clinical trials for drug therapy and few well designed intervention studies for control of vectors or canine reservoirs. Conclusion Elimination of zoonotic VL in the Americas does not seem a realistic goal at this point given the lack of political commitment, gaps in scientific knowledge, and the weakness of case management and surveillance systems. Research priorities and current strategies should be reviewed with the aim of achieving better VL control. PMID:20098726

Typhoid fever vaccination strategies.

PubMed

Date, Kashmira A; Bentsi-Enchill, Adwoa; Marks, Florian; Fox, Kimberley

2015-06-19

Typhoid vaccination is an important component of typhoid fever prevention and control, and is recommended for public health programmatic use in both endemic and outbreak settings. We reviewed experiences with various vaccination strategies using the currently available typhoid vaccines (injectable Vi polysaccharide vaccine [ViPS], oral Ty21a vaccine, and injectable typhoid conjugate vaccine [TCV]). We assessed the rationale, acceptability, effectiveness, impact and implementation lessons of these strategies to inform effective typhoid vaccination strategies for the future. Vaccination strategies were categorized by vaccine disease control strategy (preemptive use for endemic disease or to prevent an outbreak, and reactive use for outbreak control) and vaccine delivery strategy (community-based routine, community-based campaign and school-based). Almost all public health typhoid vaccination programs used ViPS vaccine and have been in countries of Asia, with one example in the Pacific and one experience using the Ty21a vaccine in South America. All vaccination strategies were found to be acceptable, feasible and effective in the settings evaluated; evidence of impact, where available, was strongest in endemic settings and in the short- to medium-term. Vaccination was cost-effective in high-incidence but not low-incidence settings. Experience in disaster and outbreak settings remains limited. TCVs have recently become available and none are WHO-prequalified yet; no program experience with TCVs was found in published literature. Despite the demonstrated success of several typhoid vaccination strategies, typhoid vaccines remain underused. Implementation lessons should be applied to design optimal vaccination strategies using TCVs which have several anticipated advantages, such as potential for use in infant immunization programs and longer duration of protection, over the ViPS and Ty21a vaccines for typhoid prevention and control. Copyright © 2015. Published by Elsevier Ltd.

Evaluation of emission control strategies for airfield operations at the Los Angeles and San Francisco International Airports. Final report

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

Gelinas, C.G.

1978-08-01

This report reviews potential air pollutant emission reductions which could be achieved by various strategies to control airfield operations at Los Angeles and San Francisco International Airports, and examines safety problems, cost impacts, potential fuel savings, time frame for strategy implementation, and potential regulatory and jurisdictional conflicts associated with each strategy. Airfield emission sources studied included aircraft operation in the idle, taxi, takeoff, and landing modes; ground service vehicles; fuel handling and storage; and aircraft engine maintenance. Nineteen potential strategies were identified, and seven strategies were selected for detailed analysis and examination after a preliminary evaluation. Two strategies, aircraft towingmore » and reducing the number of operating engines on the ground, appear to provide the most significant emission reduction. Both of these strategies offer potential reductions in the range of 20 to 40 percent of the carbon monoxide and nitrogen oxides which are currently emitted by ground operations. The aircraft towing strategy also offers a comparable improvement in suspended particulate matter emissions. When the overall feasibility of each strategy is evaluated, the strategy to reduce the number of operating engines appears to be the most viable since its implementation would result in fuel savings, no apparent safety problems, and it can be implemented immediately.« less

Research on the business QoS and trustworthy and controllable strategies mechanism for energy internet

NASA Astrophysics Data System (ADS)

Zhang, Geng; Lu, Meiling; Zhang, Dahua; Zhou, Liang; Li, Likang

2017-01-01

Energy internet is a kind of power sharing network, which can realize the bidirectional flow of energy information on the basis of the existing power grid. It puts forward higher requirements for reliability and controllability of information communication, and all kinds of business QoS of the backbone network. So the research of business QoS and trustworthy and controllable strategies mechanism have an important significance for the development of energy internet. This paper mainly studies how to use the software defined network (SDN) to achieve business QoS, and provide QoS support for all kinds of business of the energy internet. Combined with the current development situation of the energy internet in our country, this paper researches the trustworthy and controllable strategies mechanism for energy internet, and proposes the transition scheme of the IPv6 credible network architecture based on SDN. This coordinates the contradiction between the growing demand for energy internet applications and the limitations of the energy internet technology itself.

TRANSP-based Trajectory Optimization of the Current Profile Evolution to Facilitate Robust Non-inductive Ramp-up in NSTX-U

NASA Astrophysics Data System (ADS)

Wehner, William; Schuster, Eugenio; Poli, Francesca

2016-10-01

Initial progress towards the design of non-inductive current ramp-up scenarios in the National Spherical Torus Experiment Upgrade (NSTX-U) has been made through the use of TRANSP predictive simulations. The strategy involves, first, ramping the plasma current with high harmonic fast waves (HHFW) to about 400 kA, and then further ramping to 900 kA with neutral beam injection (NBI). However, the early ramping of neutral beams and application of HHFW leads to an undesirably peaked current profile making the plasma unstable to ballooning modes. We present an optimization-based control approach to improve on the non-inductive ramp-up strategy. We combine the TRANSP code with an optimization algorithm based on sequential quadratic programming to search for time evolutions of the NBI powers, the HHFW powers, and the line averaged density that define an open-loop actuator strategy that maximizes the non-inductive current while satisfying constraints associated with the current profile evolution for MHD stable plasmas. This technique has the potential of playing a critical role in achieving robustly stable non-inductive ramp-up, which will ultimately be necessary to demonstrate applicability of the spherical torus concept to larger devices without sufficient room for a central coil. Supported by the US DOE under the SCGSR Program.

Tobacco control in the Russian Federation--a policy analysis.

PubMed

Lunze, Karsten; Migliorini, Luigi

2013-01-23

The Russian Federation (Russia) has one of the highest smoking rates in the world. The purpose of this study is to analyze past and current trends of the tobacco epidemic in the Russian Federation, review current tobacco control policy responses, and identify areas of opportunity for policy priorities. We used a policy triangle as analytical framework to examine content, context, and processes of Russian tobacco control policy. The analysis was based on secondary data on supply and demand sides of the Russian tobacco epidemic, tobacco-related economic and health effects during Russia's economic transition, and compliance of Russian tobacco policy with international standards and regulations. Tobacco-promoting strategies have specifically targeted women and youth. Russia's approval of a "National Tobacco Control Concept" and draft for a comprehensive tobacco control bill increasingly align national legislature with the WHO Framework Convention on Tobacco Control (FCTC). However, several structural and cultural factors represent substantial barriers to the policy process. The influence of transnational tobacco companies on policy processes in Russia has so far impeded a full implementation of the FCTC mandates. Several strategies have been identified as having the potential to reduce the prevalence of tobacco use in Russia and decrease tobacco-related national health and economic burden: adjusting national tobacco policy by raising tobacco tax from the current lowest level in Europe to at least 70%; consequent enforcement of a complete smoking ban in public places; marketing restrictions; and smoking cessation interventions integrated into primary care. Russia's tobacco control efforts need to target women and youths specifically to efficiently counter industry efforts.

Tobacco control in the Russian Federation- a policy analysis

PubMed Central

2013-01-01

Background The Russian Federation (Russia) has one of the highest smoking rates in the world. The purpose of this study is to analyze past and current trends of the tobacco epidemic in the Russian Federation, review current tobacco control policy responses, and identify areas of opportunity for policy priorities. Methods We used a policy triangle as analytical framework to examine content, context, and processes of Russian tobacco control policy. The analysis was based on secondary data on supply and demand sides of the Russian tobacco epidemic, tobacco-related economic and health effects during Russia’s economic transition, and compliance of Russian tobacco policy with international standards and regulations. Results Tobacco-promoting strategies have specifically targeted women and youth. Russia’s approval of a “National Tobacco Control Concept” and draft for a comprehensive tobacco control bill increasingly align national legislature with the WHO Framework Convention on Tobacco Control (FCTC). However, several structural and cultural factors represent substantial barriers to the policy process. The influence of transnational tobacco companies on policy processes in Russia has so far impeded a full implementation of the FCTC mandates. Conclusions Several strategies have been identified as having the potential to reduce the prevalence of tobacco use in Russia and decrease tobacco-related national health and economic burden: adjusting national tobacco policy by raising tobacco tax from the current lowest level in Europe to at least 70%; consequent enforcement of a complete smoking ban in public places; marketing restrictions; and smoking cessation interventions integrated into primary care. Russia’s tobacco control efforts need to target women and youths specifically to efficiently counter industry efforts. PMID:23339756

Treatment of rheumatoid arthritis: a global perspective on the use of antirheumatic drugs

PubMed Central

Envalds, Minja; Pincus, Theodore

2008-01-01

Modern therapy for rheumatoid arthritis (RA) is based on knowledge of the severity of the natural history of the disease. RA patients are approached with early and aggressive treatment strategies, methotrexate as an anchor drug, biological targeted therapies in those with inadequate response to methotrexate, and “tight control,” aiming for remission and low disease activity according to quantitative monitoring. This chapter presents a rationale for current treatment strategies for RA with antirheumatic drugs, a review of published reports concerning treatments in clinical cohorts outside of clinical trials, and current treatments at 61 sites in 21 countries in the QUEST-RA database. PMID:18437286

Young and Older Adults’ Beliefs about Effective Ways to Mitigate Age-Related Memory Decline

PubMed Central

Horhota, Michelle; Lineweaver, Tara; Ositelu, Monique; Summers, Kristi; Hertzog, Christopher

2013-01-01

This study investigated whether young and older adults vary in their beliefs about the impact of various mitigating factors on age-related memory decline. Eighty young (ages 18–23) and eighty older (ages 60–82) participants reported their beliefs about their own memory abilities and the strategies that they use in their everyday lives to attempt to control their memory. Participants also reported their beliefs about memory change with age for hypothetical target individuals who were described as using (or not using) various means to mitigate memory decline. There were no age differences in personal beliefs about control over current or future memory ability. However, the two age groups differed in the types of strategies they used in their everyday life to control their memory. Young adults were more likely to use internal memory strategies, whereas older adults were more likely to focus on cognitive exercise and maintaining physical health as ways to optimize their memory ability. There were no age differences in rated memory change across the life span in hypothetical individuals. Both young and older adults perceived strategies related to improving physical and cognitive health as effective means of mitigating memory loss with age, whereas internal memory strategies were perceived as less effective means for controlling age-related memory decline. PMID:22082012

The effects of rhythm control strategies versus rate control strategies for atrial fibrillation and atrial flutter: A systematic review with meta-analysis and Trial Sequential Analysis

PubMed Central

Gluud, Christian; Jakobsen, Janus C.

2017-01-01

Background Atrial fibrillation and atrial flutter may be managed by either a rhythm control strategy or a rate control strategy but the evidence on the clinical effects of these two intervention strategies is unclear. Our objective was to assess the beneficial and harmful effects of rhythm control strategies versus rate control strategies for atrial fibrillation and atrial flutter. Methods We searched CENTRAL, MEDLINE, Embase, LILACS, Web of Science, BIOSIS, Google Scholar, clinicaltrials.gov, TRIP, EU-CTR, Chi-CTR, and ICTRP for eligible trials comparing any rhythm control strategy with any rate control strategy in patients with atrial fibrillation or atrial flutter published before November 2016. Our primary outcomes were all-cause mortality, serious adverse events, and quality of life. Our secondary outcomes were stroke and ejection fraction. We performed both random-effects and fixed-effect meta-analysis and chose the most conservative result as our primary result. We used Trial Sequential Analysis (TSA) to control for random errors. Statistical heterogeneity was assessed by visual inspection of forest plots and by calculating inconsistency (I2) for traditional meta-analyses and diversity (D2) for TSA. Sensitivity analyses and subgroup analyses were conducted to explore the reasons for substantial statistical heterogeneity. We assessed the risk of publication bias in meta-analyses consisting of 10 trials or more with tests for funnel plot asymmetry. We used GRADE to assess the quality of the body of evidence. Results 25 randomized clinical trials (n = 9354 participants) were included, all of which were at high risk of bias. Meta-analysis showed that rhythm control strategies versus rate control strategies significantly increased the risk of a serious adverse event (risk ratio (RR), 1.10; 95% confidence interval (CI), 1.02 to 1.18; P = 0.02; I2 = 12% (95% CI 0.00 to 0.32); 21 trials), but TSA did not confirm this result (TSA-adjusted CI 0.99 to 1.22). The increased risk of a serious adverse event did not seem to be caused by any single component of the composite outcome. Meta-analysis showed that rhythm control strategies versus rate control strategies were associated with better SF-36 physical component score (mean difference (MD), 6.93 points; 95% CI, 2.25 to 11.61; P = 0.004; I2 = 95% (95% CI 0.94 to 0.96); 8 trials) and ejection fraction (MD, 4.20%; 95% CI, 0.54 to 7.87; P = 0.02; I2 = 79% (95% CI 0.69 to 0.85); 7 trials), but TSA did not confirm these results. Both meta-analysis and TSA showed no significant differences on all-cause mortality, SF-36 mental component score, Minnesota Living with Heart Failure Questionnaire, and stroke. Conclusions Rhythm control strategies compared with rate control strategies seem to significantly increase the risk of a serious adverse event in patients with atrial fibrillation. Based on current evidence, it seems that most patients with atrial fibrillation should be treated with a rate control strategy unless there are specific reasons (e.g., patients with unbearable symptoms due to atrial fibrillation or patients who are hemodynamically unstable due to atrial fibrillation) justifying a rhythm control strategy. More randomized trials at low risk of bias and low risk of random errors are needed. Trial registration PROSPERO CRD42016051433 PMID:29073191

Naval Operations Concept 2010: Implementing the Maritime Strategy

DTIC Science & Technology

2010-01-01

Naval Operations Concept 2010 Implementing The Maritime Strategy Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden...Directorate for Information Operations and Reports , 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that...display a currently valid OMB control number. 1. REPORT DATE 2010 2. REPORT TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND

Detection of BVDV persistently infected animals in Belgium: evaluation of the strategy implemented.

PubMed

Letellier, C; De Meulemeester, L; Lomba, M; Mijten, E; Kerkhofs, P

2005-11-15

Until now, no official bovine virus diarrhea virus (BVDV) control program has been implemented in Belgium. The only legislation dealing with the detection of BVDV-infected animals concerns the purchase of animals. A strategy of control, based on the identification and elimination of persistently infected (PI) animals and the vaccination of cows before insemination has been designed in both the Northern and the Southern part of the country. The strategy of detection of PI animals relies on PCR testing of pools of blood. Individual blood samples corresponding to the positive pools are then tested by BVDV-antigen ELISA. A first evaluation of the measures already applied in Belgium is presented. Data obtained in 2003 are presented and discussed regarding the validation of the laboratory strategy, the prevalence of positive herds, the genotype of circulating viruses, the outcome of antigen positive animals and the need for improvement of the current legislation.

Nanomedicine strategies for sustained, controlled and targeted treatment of cancer stem cells.

PubMed

Gao, Jie; Li, Wei; Guo, Yajun; Feng, Si-Shen

2016-12-01

Cancer stem cells (CSCs) are original cancer cells that are of characteristics associated with normal stem cells. CSCs are toughest against various treatments and thus responsible for cancer metastasis and recurrence. Therefore, development of specific and effective treatment of CSCs plays a key role in improving survival and life quality of cancer patients, especially those in the metastatic stage. Nanomedicine strategies, which include prodrugs, micelles, liposomes and nanoparticles of biodegradable polymers, could substantially improve the therapeutic index of conventional therapeutics due to its manner of sustained, controlled and targeted delivery of high transportation efficiency across the cell membrane and low elimination by intracellular autophagy, and thus provide a practical solution to solve the problem encountered in CSCs treatment. This review gives briefly the latest information to summarize the concept, strategies, mechanisms and current status as well as future promises of nanomedicine strategies for treatment of CSCs.

The interplay between mosquitoes, entomopathogens and symbiotic microbes: A niche for the development of novel microbial-derived vector control strategies

USDA-ARS?s Scientific Manuscript database

The current outbreak of Zika virus in the Americas has highlighted the need for improved methods of control. This concern is exacerbated if we consider that all three major arboviruses (Zika, dengue, and chikungunya virus) are transmitted efficiently by two wide spread mosquito vectors: Aedes aegypt...

Amoeba-related health risk in drinking water systems: could monitoring of amoebae be a complementary approach to current quality control strategies?

PubMed

Codony, Francesc; Pérez, Leonardo Martín; Adrados, Bárbara; Agustí, Gemma; Fittipaldi, Mariana; Morató, Jordi

2012-01-01

Culture-based methods for fecal indicator microorganisms are the standard protocol to assess potential health risk from drinking water systems. However, these traditional fecal indicators are inappropriate surrogates for disinfection-resistant fecal pathogens and the indigenous pathogens that grow in drinking water systems. There is now a range of molecular-based methods, such as quantitative PCR, which allow detection of a variety of pathogens and alternative indicators. Hence, in addition to targeting total Escherichia coli (i.e., dead and alive) for the detection of fecal pollution, various amoebae may be suitable to indicate the potential presence of pathogenic amoeba-resisting microorganisms, such as Legionellae. Therefore, monitoring amoeba levels by quantitative PCR could be a useful tool for directly and indirectly evaluating health risk and could also be a complementary approach to current microbial quality control strategies for drinking water systems.

Current status, challenges and perspectives in the development of vaccines against yellow fever, dengue, Zika and chikungunya viruses.

PubMed

Silva, José V J; Lopes, Thaísa R R; Oliveira-Filho, Edmilson F de; Oliveira, Renato A S; Durães-Carvalho, Ricardo; Gil, Laura H V G

2018-06-01

Emerging and re-emerging viral infections transmitted by insect vectors (arthopode-borne viruses, arbovirus) are a serious threat to global public health. Among them, yellow fever (YFV), dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses are particularly important in tropical and subtropical regions. Although vector control is one of the most used prophylactic measures against arboviruses, it often faces obstacles, such as vector diversity, uncontrolled urbanization and increasing resistance to insecticides. In this context, vaccines may be the best control strategy for arboviral diseases. Here, we provide a general overview about licensed vaccines and the most advanced vaccine candidates against YFV, DENV, CHIKV and ZIKV. In particular, we highlight vaccine difficulties, the current status of the most advanced strategies and discuss how the molecular characteristics of each virus can influence the choice of the different vaccine formulations. Copyright © 2018 Elsevier B.V. All rights reserved.

Incorporating uncertainty in watershed management decision-making: A mercury TMDL case study

USGS Publications Warehouse

Labiosa, W.; Leckie, J.; Shachter, R.; Freyberg, D.; Rytuba, J.; ,

2005-01-01

Water quality impairment due to high mercury fish tissue concentrations and high mercury aqueous concentrations is a widespread problem in several sub-watersheds that are major sources of mercury to the San Francisco Bay. Several mercury Total Maximum Daily Load regulations are currently being developed to address this problem. Decisions about control strategies are being made despite very large uncertainties about current mercury loading behavior, relationships between total mercury loading and methyl mercury formation, and relationships between potential controls and mercury fish tissue levels. To deal with the issues of very large uncertainties, data limitations, knowledge gaps, and very limited State agency resources, this work proposes a decision analytical alternative for mercury TMDL decision support. The proposed probabilistic decision model is Bayesian in nature and is fully compatible with a "learning while doing" adaptive management approach. Strategy evaluation, sensitivity analysis, and information collection prioritization are examples of analyses that can be performed using this approach.

Usefulness of Novel Immunotherapeutic Strategies for Idiopathic Recurrent Pericarditis.

PubMed

Lotan, Dor; Wasserstrum, Yishay; Fardman, Alexander; Kogan, Michael; Adler, Yehuda

2016-03-01

Idiopathic recurrent pericarditis (IRP) is a debilitating illness which leads to great suffering and multiple hospitalizations. Management of acute pericarditis and subsequent recurrences has evolved significantly as the use of colchicine-based strategies become more prevalent, yet there still remains a subset of patients who remain refractory to colchicine therapy, and these patients require prolonged corticosteroid (CS) therapy for the control of symptoms. Since the 1960s, there have been reports of successful management of these cases with immunosuppressive therapy. Current guidelines support the use of anakinra, intravenous immunoglobulins, and azathioprine for management of IRP, with the goals of both control of symptoms and withdrawal of CS. Recent reports supply evidence for both auto-inflammatory and autoimmune activity in these patients. We herein review the current available reports regarding the evidence regarding the pathophysiology and reported cases and case series of IRP cases managed with immunomodulation therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical Interventions for Hyperacusis in Adults: A Scoping Review to Assess the Current Position and Determine Priorities for Research

PubMed Central

Potgieter, Iskra; Baguley, David M.

2017-01-01

Background There is no universally accepted definition for hyperacusis, but in general it is characterised by decreased sound tolerance to ordinary environmental sounds. Despite hyperacusis being prevalent and having significant clinical implications, much remains unknown about current management strategies. Purpose To establish the current position of research on hyperacusis and identify research gaps to direct future research. Design and Sample Using an established methodological framework, electronic and manual searches of databases and journals identified 43 records that met our inclusion criteria. Incorporating content and thematic analysis approaches, the definitions of hyperacusis, management strategies, and outcome measures were catalogued. Results Only 67% of the studies provided a definition of hyperacusis, such as “reduced tolerance” or “oversensitivity to sound.” Assessments and outcome measures included Loudness Discomfort Levels, the Hyperacusis Questionnaire, and Tinnitus Retraining Therapy (TRT) interview. Management strategies reported were Cognitive Behavioural Therapy, TRT, devices, pharmacological therapy, and surgery. Conclusions Management strategies were typically evaluated in patients reporting hyperacusis as a secondary complaint or as part of a symptom set. As such the outcomes reported only provided an indication of their effectiveness for hyperacusis. Randomised Controlled Trials are needed to evaluate the effectiveness of management strategies for patients experiencing hyperacusis. PMID:29312994

Gender-Differentiated Parenting Revisited: Meta-Analysis Reveals Very Few Differences in Parental Control of Boys and Girls

PubMed Central

Endendijk, Joyce J.; Groeneveld, Marleen G.; Bakermans-Kranenburg, Marian J.; Mesman, Judi

2016-01-01

Although various theories describe mechanisms leading to differential parenting of boys and girls, there is no consensus about the extent to which parents do treat their sons and daughters differently. The last meta-analyses on the subject were conducted more than fifteen years ago, and changes in gender-specific child rearing in the past decade are quite plausible. In the current set of meta-analyses, based on 126 observational studies (15,034 families), we examined mothers’ and fathers’ differential use of autonomy-supportive and controlling strategies with boys and girls, and the role of moderators related to the decade in which the study was conducted, the observational context, and sample characteristics. Databases of Web of Science, ERIC, PsychInfo, Online Contents, Picarta, and Proquest were searched for studies examining differences in observed parental control of boys and girls between the ages of 0 and 18 years. Few differences were found in parents’ use of control with boys and girls. Parents were slightly more controlling with boys than with girls, but the effect size was negligible (d = 0.08). The effect was larger, but still small, in normative groups and in samples with younger children. No overall effect for gender-differentiated autonomy-supportive strategies was found (d = 0.03). A significant effect of time emerged: studies published in the 1970s and 1980s reported more autonomy-supportive strategies with boys than toward girls, but from 1990 onwards parents showed somewhat more autonomy-supportive strategies with girls than toward boys. Taking into account parents’ gender stereotypes might uncover subgroups of families where gender-differentiated control is salient, but based on our systematic review of the currently available large data base we conclude that in general the differences between parenting of boys versus girls are minimal. PMID:27416099

A control approach for robots with flexible links and rigid end-effectors

NASA Technical Reports Server (NTRS)

Barbieri, Enrique; Ozguner, Umit

1989-01-01

Multiarm flexible robots with dexterous end effectors are currently being considered in such tasks as satellite retrieval, servicing and repair where a two phase problem can be identified: Phase 1, robot positioning in space; Phase 2, object retrieval. Some issues in Phase 1 regarding modelling and control strategies for a robotic system comprised of along flexible arm and a rigid three-link end effector are presented. The control objective is to maintain the last (rigid) link stationary in space in the presence of an additive disturbance caused by the flexible energy in the first link after a positioning maneuver has been accomplished. Several configuration strategies can be considered, and optimal decentralized servocompensators can be designed. Preliminary computer simulations are included for a simple proportional controller to illustrate the approach.

Management status of end-of-life vehicles and development strategies of used automotive electronic control components recycling industry in China.

PubMed

Wang, Junjun; Chen, Ming

2012-11-01

Recycling companies play a leading role in the system of end-of-life vehicles (ELVs) in China. Automotive manufacturers in China are rarely involved in recycling ELVs, and they seldom provide dismantling information for recycling companies. In addition, no professional shredding plant is available. The used automotive electronic control components recycling industry in China has yet to take shape because of the lack of supporting technology and profitable models. Given the rapid growth of the vehicle population and electronic control units in automotives in China, the used automotive electronic control components recycling industry requires immediate development. This paper analyses the current recycling system of ELVs in China and introduces the automotive product recycling technology roadmap as well as the recycling industry development goals. The strengths, weaknesses, opportunities and challenges of the current used automotive electronic control components recycling industry in China are analysed comprehensively based on the 'strengths, weaknesses, opportunities and threats' (SWOT) method. The results of the analysis indicate that this recycling industry responds well to all the factors and has good opportunities for development. Based on the analysis, new development strategies for the used automotive electronic control components recycling industry in accordance with the actual conditions of China are presented.

Management and modeling approaches for controlling raccoon rabies: The road to elimination

PubMed Central

Chipman, Richard B.; Slate, Dennis; Huyvaert, Kathryn P.; VerCauteren, Kurt C.; Gilbert, Amy T.

2017-01-01

Rabies is an ancient viral disease that significantly impacts human and animal health throughout the world. In the developing parts of the world, dog bites represent the highest risk of rabies infection to people, livestock, and other animals. However, in North America, where several rabies virus variants currently circulate in wildlife, human contact with the raccoon rabies variant leads to the highest per capita population administration of post-exposure prophylaxis (PEP) annually. Previous rabies variant elimination in raccoons (Canada), foxes (Europe), and dogs and coyotes (United States) demonstrates that elimination of the raccoon variant from the eastern US is feasible, given an understanding of rabies control costs and benefits and the availability of proper tools. Also critical is a cooperatively produced strategic plan that emphasizes collaborative rabies management among agencies and organizations at the landscape scale. Common management strategies, alone or as part of an integrated approach, include the following: oral rabies vaccination (ORV), trap-vaccinate-release (TVR), and local population reduction. As a complement, mathematical and statistical modeling approaches can guide intervention planning, such as through contact networks, circuit theory, individual-based modeling, and others, which can be used to better understand and predict rabies dynamics through simulated interactions among the host, virus, environment, and control strategy. Strategies derived from this ecological lens can then be optimized to produce a management plan that balances the ecological needs and program financial resources. This paper discusses the management and modeling strategies that are currently used, or have been used in the past, and provides a platform of options for consideration while developing raccoon rabies virus elimination strategies in the US. PMID:28301480

Management and modeling approaches for controlling raccoon rabies: The road to elimination.

PubMed

Elmore, Stacey A; Chipman, Richard B; Slate, Dennis; Huyvaert, Kathryn P; VerCauteren, Kurt C; Gilbert, Amy T

2017-03-01

Rabies is an ancient viral disease that significantly impacts human and animal health throughout the world. In the developing parts of the world, dog bites represent the highest risk of rabies infection to people, livestock, and other animals. However, in North America, where several rabies virus variants currently circulate in wildlife, human contact with the raccoon rabies variant leads to the highest per capita population administration of post-exposure prophylaxis (PEP) annually. Previous rabies variant elimination in raccoons (Canada), foxes (Europe), and dogs and coyotes (United States) demonstrates that elimination of the raccoon variant from the eastern US is feasible, given an understanding of rabies control costs and benefits and the availability of proper tools. Also critical is a cooperatively produced strategic plan that emphasizes collaborative rabies management among agencies and organizations at the landscape scale. Common management strategies, alone or as part of an integrated approach, include the following: oral rabies vaccination (ORV), trap-vaccinate-release (TVR), and local population reduction. As a complement, mathematical and statistical modeling approaches can guide intervention planning, such as through contact networks, circuit theory, individual-based modeling, and others, which can be used to better understand and predict rabies dynamics through simulated interactions among the host, virus, environment, and control strategy. Strategies derived from this ecological lens can then be optimized to produce a management plan that balances the ecological needs and program financial resources. This paper discusses the management and modeling strategies that are currently used, or have been used in the past, and provides a platform of options for consideration while developing raccoon rabies virus elimination strategies in the US.

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.

Delivery strategies to control inflammatory response: Modulating M1-M2 polarization in tissue engineering applications.

PubMed

Alvarez, Mario Moisés; Liu, Julie C; Trujillo-de Santiago, Grissel; Cha, Byung-Hyun; Vishwakarma, Ajaykumar; Ghaemmaghami, Amir M; Khademhosseini, Ali

2016-10-28

Macrophages are key players in many physiological scenarios including tissue homeostasis. In response to injury, typically the balance between macrophage sub-populations shifts from an M1 phenotype (pro-inflammatory) to an M2 phenotype (anti-inflammatory). In tissue engineering scenarios, after implantation of any device, it is desirable to exercise control on this M1-M2 progression and to ensure a timely and smooth transition from the inflammatory to the healing stage. In this review, we briefly introduce the current state of knowledge regarding macrophage function and nomenclature. Next, we discuss the use of controlled release strategies to tune the balance between the M1 and M2 phenotypes in the context of tissue engineering applications. We discuss recent literature related to the release of anti-inflammatory molecules (including nucleic acids) and the sequential release of cytokines to promote a timely M1-M2 shift. In addition, we describe the use of macrophages as controlled release agents upon stimulation by physical and/or mechanical cues provided by scaffolds. Moreover, we discuss current and future applications of "smart" implantable scaffolds capable of controlling the cascade of biochemical events related to healing and vascularization. Finally, we provide our opinion on the current challenges and the future research directions to improve our understanding of the M1-M2 macrophage balance and properly exploit it in tissue engineering and regenerative medicine applications. Copyright © 2016 Elsevier B.V. All rights reserved.

Delivery strategies to control inflammatory response: Modulating M1-M2 polarization in tissue engineering applications

PubMed Central

Alvarez, Mario Moisés; Liu, Julie C.; Santiago, Grissel Trujillo-de; Cha, Byung-Hyun; Vishwakarma, Ajaykumar; Ghaemmaghami, Amir; Khademhosseini, Ali

2016-01-01

Macrophages are key players in many physiological scenarios including tissue homeostasis. In response to injury, typically the balance between macrophage sub-populations shifts from an M1 phenotype (pro-inflammatory) to an M2 phenotype (anti-inflammatory). In tissue engineering scenarios, after implantation of any device, it is desirable to exercise control on this M1-M2 progression and to ensure a timely and smooth transition from the inflammatory to the healing stage. In this review, we briefly introduce the current state of knowledge regarding macrophage function and nomenclature. Next, we discuss the use of controlled release strategies to tune the balance between the M1 and M2 phenotypes in the context of tissue engineering applications. We discuss recent literature related to the release of anti-inflammatory molecules (including nucleic acids) and the sequential release of cytokines to promote a timely M1-M2 shift. In addition, we describe the use of macrophages as controlled release agents upon stimulation by physical and/or mechanical cues provided by scaffolds. Moreover, we discuss current and future applications of “smart” implantable scaffolds capable of controlling the cascade of biochemical events related to healing and vascularization. Finally, we provide our opinion on the current challenges and the future research directions to improve our understanding of the M1-M2 macrophage balance and properly exploit it in tissue engineering and regenerative medicine applications. PMID:26778695

Attack Vulnerability of Network Controllability

PubMed Central

2016-01-01

Controllability of complex networks has attracted much attention, and understanding the robustness of network controllability against potential attacks and failures is of practical significance. In this paper, we systematically investigate the attack vulnerability of network controllability for the canonical model networks as well as the real-world networks subject to attacks on nodes and edges. The attack strategies are selected based on degree and betweenness centralities calculated for either the initial network or the current network during the removal, among which random failure is as a comparison. It is found that the node-based strategies are often more harmful to the network controllability than the edge-based ones, and so are the recalculated strategies than their counterparts. The Barabási-Albert scale-free model, which has a highly biased structure, proves to be the most vulnerable of the tested model networks. In contrast, the Erdős-Rényi random model, which lacks structural bias, exhibits much better robustness to both node-based and edge-based attacks. We also survey the control robustness of 25 real-world networks, and the numerical results show that most real networks are control robust to random node failures, which has not been observed in the model networks. And the recalculated betweenness-based strategy is the most efficient way to harm the controllability of real-world networks. Besides, we find that the edge degree is not a good quantity to measure the importance of an edge in terms of network controllability. PMID:27588941

Attack Vulnerability of Network Controllability.

PubMed

Lu, Zhe-Ming; Li, Xin-Feng

2016-01-01

Controllability of complex networks has attracted much attention, and understanding the robustness of network controllability against potential attacks and failures is of practical significance. In this paper, we systematically investigate the attack vulnerability of network controllability for the canonical model networks as well as the real-world networks subject to attacks on nodes and edges. The attack strategies are selected based on degree and betweenness centralities calculated for either the initial network or the current network during the removal, among which random failure is as a comparison. It is found that the node-based strategies are often more harmful to the network controllability than the edge-based ones, and so are the recalculated strategies than their counterparts. The Barabási-Albert scale-free model, which has a highly biased structure, proves to be the most vulnerable of the tested model networks. In contrast, the Erdős-Rényi random model, which lacks structural bias, exhibits much better robustness to both node-based and edge-based attacks. We also survey the control robustness of 25 real-world networks, and the numerical results show that most real networks are control robust to random node failures, which has not been observed in the model networks. And the recalculated betweenness-based strategy is the most efficient way to harm the controllability of real-world networks. Besides, we find that the edge degree is not a good quantity to measure the importance of an edge in terms of network controllability.

Integrated Pest Management of Coffee Berry Borer: Strategies from Latin America that Could Be Useful for Coffee Farmers in Hawaii

PubMed Central

Aristizábal, Luis F.; Bustillo, Alex E.; Arthurs, Steven P.

2016-01-01

The coffee berry borer (CBB), Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae) is the primary arthropod pest of coffee plantations worldwide. Since its detection in Hawaii (September 2010), coffee growers are facing financial losses due to reduced quality of coffee yields. Several control strategies that include cultural practices, biological control agents (parasitoids), chemical and microbial insecticides (entomopathogenic fungi), and a range of post-harvest sanitation practices have been conducted to manage CBB around the world. In addition, sampling methods including the use of alcohol based traps for monitoring CBB populations have been implemented in some coffee producing countries in Latin America. It is currently unclear which combination of CBB control strategies is optimal under economical, environmental, and sociocultural conditions of Hawaii. This review discusses components of an integrated pest management program for CBB. We focus on practical approaches to provide guidance to coffee farmers in Hawaii. Experiences of integrated pest management (IPM) of CBB learned from Latin America over the past 25 years may be relevant for establishing strategies of control that may fit under Hawaiian coffee farmers’ conditions. PMID:26848690

A New Type Hi-Speed BLDC Control System Base on Indirect Current Control Strategy

NASA Astrophysics Data System (ADS)

Wang, D. P.; Wang, Y. C.; Zhang, F. G.; Jin, S.

2017-05-01

High speed BLDC has the characteristic as larger air gap smaller armature inductance, traditional PWM modulation will produce a great number of high frequency current harmonics which led problem like large torque ripple and serious motor heat. In the meantime traditional PWM modulation use the diode rectifier which cause harmonic pollution in electric power net. To solve the problem above, proposes a new motor controller topology. Using the IGBT device to replace the diode on frequency converter rectifier side, apply the power factor correction technology, reduce the pollution on the grid. Using busbar current modulation on the inverter, driving bridge-arm use 3-phase 6-state open as driving Mode, realize the control on a 10000r/min,10kw BLDC. The results of Simulation on matlab show the topological structure as proposed can effectively improve the network side power factor and reduce the motor armature winding harmonic and motor torque ripple.

Effect of current emission abatement strategies on air quality improvement in China: A case study of Baotou, a typical industrial city in Inner Mongolia.

PubMed

Qiu, Xionghui; Duan, Lei; Cai, Siyi; Yu, Qian; Wang, Shuxiao; Chai, Fahe; Gao, Jian; Li, Yanping; Xu, Zhaoming

2017-07-01

The national Air Pollution Prevention and Control Action Plan required significant decreases in PM 2.5 levels over China. To explore more effective emission abatement strategies in industrial cities, a case study was conducted in Baotou to evaluate the current national control measures. The total emissions of SO 2, NO X , PM 2.5 and NMVOC (non-methane volatile organic compounds) in Baotou were 211.2Gg, 156.1Gg, 28.8Gg, and 48.5Gg, respectively in 2013, and they would experience a reduction of 30.4%, 26.6%, 15.1%, and 8.7%, respectively in 2017 and 39.0%, 32.0%, 24.4%, and 12.9%, respectively in 2020. The SO 2 , NO X and PM 2.5 emissions from the industrial sector would experience a greater decrease, with reductions of 37%, 32.7 and 24.3%, respectively. From 2013 to 2020, the concentrations of SO 2 , NO 2 , and PM 2.5 are expected to decline by approximately 30%, 10% and 14.5%, respectively. The reduction rate of SNA (sulfate, nitrate and ammonium) concentrations was significantly higher than that of PM 2.5 in 2017, implying that the current key strategy toward controlling air pollutants from the industrial sector is more powerful for SNA. Although air pollution control measures implemented in the industrial sector could greatly reduce total emissions, constraining the emissions from lower sources such as residential coal combustion would be more effective in decreasing the concentration of PM 2.5 from 2017 to 2020. These results suggest that even for a typical industrial city, the reduction of PM 2.5 concentrations not only requires decreases in emissions from the industrial sector, but also from the low emission sources. The seasonal variation in sulfate concentration also showed that emission from coal-burning is the key factor to control during the heating season. Copyright © 2016. Published by Elsevier B.V.

The role of movement restrictions and pre-emptive destruction in the emergency control strategy against CSF outbreaks in domestic pigs.

PubMed

Thulke, Hans-Hermann; Eisinger, Dirk; Beer, Martin

2011-04-01

Classical swine fever (CSF) outbreaks in domestic pig herds lead to the implementation of standard control measures according to legislative regulations. Ideal outbreak control entails the swift and efficient culling of all pigs on premises detected positive for CSF virus. Often all pig holdings around the detected cases are pre-emptively destroyed to exclude transmission into the neighbourhood. In addition to these measures, zones are defined in which surveillance and protection measures are intensified to prevent further distant disease spread. In particular, all movements are prohibited within standstill areas. Standstill also excludes the transport of fattened pigs to slaughter. Historical outbreaks provide evidence of the success of this control strategy. However, the extent to which the individual strategy elements contribute to this success is unknown. Therefore, we applied a spatially and temporally explicit epidemic model to the problem. Its rule-based formulation is tailored to a one-by-one model implementation of existing control concepts. Using a comparative model analysis the individual contributions of single measures to overall control success were revealed. From the results of the model we concluded that movement restrictions had the dominant impact on strategy performance suggesting a reversal of the current conceptual thinking. Additional measures such as pre-emptive culling only became relevant under imperfect compliance with movement restrictions. The importance of movement restrictions for the overall control success illustrates the need for explicit consideration of this measure when contingency strategies are being amended (e.g. emergency vaccination) and associated risks assessed. Copyright © 2011 Elsevier B.V. All rights reserved.

A systematic review of current and emergent manipulator control approaches

NASA Astrophysics Data System (ADS)

Ajwad, Syed Ali; Iqbal, Jamshed; Ullah, Muhammad Imran; Mehmood, Adeel

2015-06-01

Pressing demands of productivity and accuracy in today's robotic applications have highlighted an urge to replace classical control strategies with their modern control counterparts. This recent trend is further justified by the fact that the robotic manipulators have complex nonlinear dynamic structure with uncertain parameters. Highlighting the authors' research achievements in the domain of manipulator design and control, this paper presents a systematic and comprehensive review of the state-of-the-art control techniques that find enormous potential in controlling manipulators to execute cuttingedge applications. In particular, three kinds of strategies, i.e., intelligent proportional-integral-derivative (PID) scheme, robust control and adaptation based approaches, are reviewed. Future trend in the subject area is commented. Open-source simulators to facilitate controller design are also tabulated. With a comprehensive list of references, it is anticipated that the review will act as a firsthand reference for researchers, engineers and industrialinterns to realize the control laws for multi-degree of freedom (DOF) manipulators.

Etiology and sequelae of root resorption.

PubMed

Vlaskalic, V; Boyd, R L; Baumrind, S

1998-06-01

This article reviews the current status of investigation into apical root resorption within the context of orthodontic treatment. Treatment and patient factors that have traditionally been investigated are discussed, along with the results of current research in this area. The need for rethinking traditional research strategies in the quest for identifying both control and causative mechanisms is explored. Finally, proposals for key areas of future interest are highlighted.

Fivefold confinement time increase in the Madison Symmetric Torus using inductive poloidal current drive

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

Stoneking, M.R.; Lanier, N.E.; Prager, S.C.

1996-12-01

Current profile control is employed in the Madison Symmetric Torus reversed field pinch to reduce the magnetic fluctuations responsible for anomalous transport. An inductive poloidal electric field pulse is applied in the sense to flatten the parallel current profile, reducing the dynamo fluctuation amplitude required to sustain the equilibrium. This technique demonstrates a substantial reduction in fluctuation amplitude (as much as 50%), and improvement in energy confinement (from 1 ms to 5 ms); a record low fluctuation (0.8%) and record high temperature (615 eV) for this device were observed simultaneously during current drive experiments. Plasma beta increases by 50% andmore » the Ohmic input power is three times lower. Particle confinement improves and plasma impurity contamination is reduced. The results of the transient current drive experiments provide motivation for continuing development of steady-state current profile control strategies for the reversed field pinch.« less

State feedback control design for Boolean networks.

PubMed

Liu, Rongjie; Qian, Chunjiang; Liu, Shuqian; Jin, Yu-Fang

2016-08-26

Driving Boolean networks to desired states is of paramount significance toward our ultimate goal of controlling the progression of biological pathways and regulatory networks. Despite recent computational development of controllability of general complex networks and structural controllability of Boolean networks, there is still a lack of bridging the mathematical condition on controllability to real boolean operations in a network. Further, no realtime control strategy has been proposed to drive a Boolean network. In this study, we applied semi-tensor product to represent boolean functions in a network and explored controllability of a boolean network based on the transition matrix and time transition diagram. We determined the necessary and sufficient condition for a controllable Boolean network and mapped this requirement in transition matrix to real boolean functions and structure property of a network. An efficient tool is offered to assess controllability of an arbitrary Boolean network and to determine all reachable and non-reachable states. We found six simplest forms of controllable 2-node Boolean networks and explored the consistency of transition matrices while extending these six forms to controllable networks with more nodes. Importantly, we proposed the first state feedback control strategy to drive the network based on the status of all nodes in the network. Finally, we applied our reachability condition to the major switch of P53 pathway to predict the progression of the pathway and validate the prediction with published experimental results. This control strategy allowed us to apply realtime control to drive Boolean networks, which could not be achieved by the current control strategy for Boolean networks. Our results enabled a more comprehensive understanding of the evolution of Boolean networks and might be extended to output feedback control design.

Real power regulation design for multi-terminal VSC-HVDC systems

NASA Astrophysics Data System (ADS)

Li, Guo-Jie; Ruan, Si-Ye; Lie, Tek Tjing

2013-06-01

A multi-terminal voltage-source-converter (VSC) based high voltage direct current (HVDC) system is concerned for its flexibility and reliability. In this study, a control strategy for multiple VSCs is proposed to auto-share the real power variation without changing control mode, which is based on "dc voltage droop" power regulation functions. With the proposed power regulation design, the multiple VSCs automatically share the real power change and the VSC-HVDC system is stable even under loss of any one converter while there is no overloading for any individual converter. Simulation results show that it is effective to balance real power for power disturbance and thus improves operation reliability for the multi-terminal VSC-HVDC system by the proposed control strategy.

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.

Controlling liver cancer internationally: A qualitative study of clinicians' perceptions of current public policy needs.

PubMed

Bridges, John Fp; Gallego, Gisselle; Blauvelt, Barri M

2011-07-28

Liver cancer is the fifth most common cancer in men and the seventh for women. Usually because of late diagnosis, the prognosis for liver cancer remains poor, resulting in liver cancer being the third most common cause of death from cancer. While some countries have treatment guidelines, little is known or understood about the strategies needed for liver cancer control internationally. To explore leading liver cancer clinician's perceptions of the current public policy needs to control liver cancer internationally. Key informant interviews were conducted with a range of liver cancer clinicians involved in policy in eleven countries. Interviews were digitally recorded, transcribed verbatim, translated (where necessary), de-identified and analyzed by two researchers using a constant comparative method. Twenty in-depth semi-structured interviews were conducted in: Australia, China, France, Germany, Italy, Japan, Spain, South Korea, Taiwan, Turkey and the United States. Nine themes were identified and cluster into three groups: 1) Promoting prevention via early risk assessment, focusing on viral hepatitis and other lifestyle factors; 2) Increasing political, public and medical community awareness; and 3) Improving funding for screening, liver cancer surveillance and treatment. This study is an important step towards developing an evidence-based approach to assessing preparedness for implementing comprehensive liver cancer control strategies. Evaluation mechanisms to assess countries' performance on the needs described are needed. Future research will concentrate of understanding how these needs vary across countries and the optimal strategies to improve the diagnosis and prognosis of patients with liver cancer internationally.

Unique contributions of emotion regulation and executive functions in predicting the quality of parent-child interaction behaviors.

PubMed

Shaffer, Anne; Obradović, Jelena

2017-03-01

Parenting is a cognitive, emotional, and behavioral endeavor, yet limited research investigates parents' executive functions and emotion regulation as predictors of how parents interact with their children. The current study is a multimethod investigation of parental self-regulation in relation to the quality of parenting behavior and parent-child interactions in a diverse sample of parents and kindergarten-age children. Using path analyses, we tested how parent executive functions (inhibitory control) and lack of emotion regulation strategies uniquely relate to both sensitive/responsive behaviors and positive/collaborative behaviors during observed interaction tasks. In our analyses, we accounted for parent education, financial stress, and social support as socioeconomic factors that likely relate to parent executive function and emotion regulation skills. In a diverse sample of primary caregivers (N = 102), we found that direct assessment of parent inhibitory control was positively associated with sensitive/responsive behaviors, whereas parent self-reported difficulties in using emotion regulation strategies were associated with lower levels of positive and collaborative dyadic behaviors. Parent education and financial stress predicted inhibitory control, and social support predicted emotion regulation difficulties; parent education was also a significant predictor of sensitive/responsive behaviors. Greater inhibitory control skills and fewer difficulties identifying effective emotion regulation strategies were not significantly related in our final path model. We discuss our findings in the context of current and emerging parenting interventions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Social anxiety and alcohol-related negative consequences among college drinkers: do protective behavioral strategies mediate the association?

PubMed

Villarosa, Margo C; Moorer, Kayla D; Madson, Michael B; Zeigler-Hill, Virgil; Noble, Jeremy J

2014-09-01

The link between social anxiety and alcohol-related negative consequences among college students has been well documented. Protective behavioral strategies are cognitive-behavioral strategies that college students use in an effort to reduce harm while they are drinking. In the current study we examined the mediating role of the 2 categories of protective behavioral strategies (i.e., controlled consumption and serious harm reduction) in the relationship that social anxiety symptoms have with alcohol-related negative consequences. Participants were 572 undergraduates who completed measures of social anxiety, alcohol use, negative consequences of alcohol use, and protective behavioral strategy use. Only serious harm reduction strategies emerged as a mediator of the association that social anxiety symptoms had with alcohol-related negative consequences. Clinical and research implications are discussed.

Cost-benefit analysis of foot and mouth disease control in Ethiopia.

PubMed

Jemberu, Wudu T; Mourits, Monique; Rushton, Jonathan; Hogeveen, Henk

2016-09-15

Foot and mouth disease (FMD) occurs endemically in Ethiopia. Quantitative insights on its national economic impact and on the costs and benefits of control options are, however, lacking to support decision making in its control. The objectives of this study were, therefore, to estimate the annual costs of FMD in cattle production systems of Ethiopia, and to conduct an ex ante cost-benefit analysis of potential control alternatives. The annual costs of FMD were assessed based on production losses, export losses and control costs. The total annual costs of FMD under the current status quo of no official control program were estimated at 1354 (90% CR: 864-2042) million birr. The major cost (94%) was due to production losses. The costs and benefits of three potential control strategies: 1) ring vaccination (reactive vaccination around outbreak area supported by animal movement restrictions, 2) targeted vaccination (annual preventive vaccination in high risk areas plus ring vaccination in the rest of the country), and 3) preventive mass vaccination (annual preventive vaccination of the whole national cattle population) were compared with the baseline scenario of no official control program. Experts were elicited to estimate the influence of each of the control strategies on outbreak incidence and number of cases per outbreak. Based on these estimates, the incidence of the disease was simulated stochastically for 10 years. Preventive mass vaccination was epidemiologically the most efficient control strategy by reducing the national outbreak incidence below 5% with a median time interval of 3 years, followed by targeted vaccination strategy with a corresponding median time interval of 5 years. On average, all evaluated control strategies resulted in positive net present values. The ranges in the net present values were, however, very wide, including negative values. The targeted vaccination strategy was the most economic strategy with a median benefit cost ratio of 4.29 (90%CR: 0.29-9.63). It was also the least risky strategy with 11% chance of a benefit cost ratio of less than one. The study indicates that FMD has a high economic impact in Ethiopia. Its control is predicted to be economically profitable even without a full consideration of gains from export. The targeted vaccination strategy is shown to provide the largest economic return with a relatively low risk of loss. More studies to generate data, especially on production impact of the disease and effectiveness of control measures are needed to improve the rigor of future analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Therapeutic vaccines in HBV: lessons from HCV.

PubMed

Barnes, Eleanor

2015-02-01

Currently, millions of people infected with hepatitis B virus (HBV) are committed to decades of treatment with anti-viral therapy to control viral replication. However, new tools for immunotherapy that include both viral vectors and molecular checkpoint inhibitors are now available. This has led to a resurgence of interest in new strategies to develop immunotherapeutic strategies with the aim of inducing HBeAg seroconversion--an end-point that has been associated with a decrease in the rates of disease progression. Ultimately, a true cure will involve the elimination of covalently closed circular DNA which presents a greater challenge for immunotherapy. In this manuscript, I describe the development of immunotherapeutic strategies for HBV that are approaching or currently in clinical studies, and draw on observations of T cell function in natural infection supported by recent animal studies that may lead to additional rational vaccine strategies using checkpoint inhibitors. I also draw on our recent experience in developing potent vaccines for HCV prophylaxis based on simian adenoviral and MVA vectors used in prime-boost strategies in both healthy volunteers and HCV infected patients. I have shown that the induction of T cell immune responses is markedly attenuated when administered to people with persistent HCV viremia. These studies and recently published animal studies using the woodchuck model suggest that potent vaccines based on DNA or adenoviral vectored vaccination represent a rational way forward. However, combining these with drugs to suppress viral replication, alongside checkpoint inhibitors may be required to induce long-term immune control.

Transforming the Way DOD Looks at Energy. An Approach to Establishing an Energy Strategy

DTIC Science & Technology

2007-04-01

than the aromatic-containing, petroleum-based gasoline and diesel, reducing emissions . Two biofuels in current use are B20 and E85.6 These fuels...penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE APR 2007 2...areas of disconnect between DoD’s current energy consump- tion practices and the capability requirements of its strategic goals: Strategic. DoD seeks

Is anthelmintic resistance a concern for the control of human soil-transmitted helminths?

PubMed Central

Vercruysse, Jozef; Albonico, Marco; Behnke, Jerzy M.; Kotze, Andrew C.; Prichard, Roger K.; McCarthy, James S.; Montresor, Antonio; Levecke, Bruno

2011-01-01

The major human soil-transmitted helminths (STH), Ascaris lumbricoides, hookworms (Necator americanus and Ancylostoma duodenale) and Trichuris trichiura have a marked impact on human health in many parts of the world. Current efforts to control these parasites rely predominantly on periodic mass administration of anthelmintic drugs to school age children and other at-risk groups. After many years of use of these same drugs for controlling roundworms in livestock, high levels of resistance have developed, threatening the sustainability of these livestock industries in some locations. Hence, the question arises as to whether this is likely to also occur in the human STH, thereby threatening our ability to control these parasites. This is particularly important because of the recent increase in mass control programmes, relying almost exclusively on benzimidazole anthelmintics. It will be important to ensure that resistance is detected as it emerges in order to allow the implementation of mitigation strategies, such as use of drug combinations, to ensure that the effectiveness of the few existing anthelmintic drugs is preserved. In this review we address these issues by firstly examining the efficacy of anthelmintics against the human STH, and assessing whether there are any indications to date that resistance has emerged. We then consider the factors that influence the effect of current drug-use patterns in selecting for resistant parasite populations. We describe the tools currently available for resistance monitoring (field-based coprological methods), and those under development (in vitro bioassays and molecular tests), and highlight confounding factors that need to be taken into account when interpreting such resistance-monitoring data. We then highlight means to ensure that the currently available tools are used correctly, particularly with regard to study design, and we set appropriate drug-efficacy thresholds. Finally, we make recommendations for monitoring drug efficacy in the field, as components of control programmes, in order to maximise the ability to detect drug resistance, and if it arises to change control strategy and prevent the spread of resistance. PMID:24533260

U.S. National Arctic Strategy: Preparing Defensive Lines of Effort for the Arctic

DTIC Science & Technology

2014-04-01

publications hint at new political posturing and suggest China should develop a more assertive approach to the international debates on controlling ...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 01-04-2014 2. REPORT TYPE...importance of the Arctic, but lacks the infrastructure, command and control structure, and Arctic-capable assets to meet national strategic objectives

Recombinant probiotics with antimicrobial peptides: a dual strategy to improve immune response in immunocompromised patients.

PubMed

Mandal, Santi M; Silva, Osmar N; Franco, Octavio L

2014-08-01

Bacterial infectious diseases are currently a serious health problem, especially in patients compromised by illness or those receiving immune-suppressant drugs. In this context, it is not only essential to improve the understanding of infectious mechanisms and host response but also to discover novel therapies with extreme urgency. Probiotics and antimicrobial peptides are also favorably viewed as novel strategies in the control of resistant bacteria. The present review will shed some light on the use of probiotic microorganisms expressing antimicrobial peptides as a dual therapy to control bacterial infectious diseases. Copyright © 2014 Elsevier Ltd. All rights reserved.

Control of malaria in the Comoro Islands over the past century.

PubMed

Chakir, Ismaël; Said, Ali Ibrahim; Affane, Bacar; Jambou, Ronan

2017-09-26

The Comoros are an archipelago located in the Indian Ocean between the eastern coasts of Africa and north of Madagascar. Malaria transmission appeared late in the 19th century due to the intensification of human migration. The story of malaria transmission for the past century is depicted to provide useful lessons for the future. Currently, malaria transmission occurs differently on each island; thus, control strategies must be adapted for each particular island. Tentative malaria control in Comoros has a long history of success and failure. This study reviews the data available as a basis for recommendations for the future. There has been much effort to reach a pre-eradication state in Anjouan and Moheli, but only control steps have been taken in the Great Comoro. To date, the primary strategy used is mass treatment of the population using artemisinin-based combination therapy (ACT), which is similar to the strategy deployed during the 1950s in other countries. ACT appears efficient in two of the three islands; however, the sustainability of the strategy is unknown. This sustainability is compromised by (i) the huge level of uncontrolled exchange between the Comoro Islands and their neighbours, increasing the risk of introducing ACT-resistant strains, (ii) the use of large quantities of pesticides for agriculture usually associated with the resistance of mosquitoes, and (iii) the cost of the actions themselves. In view of the history of malaria in this area, the first recommendation is to enhance the training of health workers and the population. The second step is to establish a national strategy to assess malaria and related factors, which is currently lacking. A survey to assess the drug sensitivity of the parasites is particularly important in a context of low transmission associated with mass treatment of the population. The last point should be to secure financial support, which is not obvious in a context of pre-elimination. The Comoro Islands are thus a living laboratory to experiments with strategies for elimination, but the future is complex.

Single-molecule electronics: Cooling individual vibrational modes by the tunneling current.

PubMed

Lykkebo, Jacob; Romano, Giuseppe; Gagliardi, Alessio; Pecchia, Alessandro; Solomon, Gemma C

2016-03-21

Electronic devices composed of single molecules constitute the ultimate limit in the continued downscaling of electronic components. A key challenge for single-molecule electronics is to control the temperature of these junctions. Controlling heating and cooling effects in individual vibrational modes can, in principle, be utilized to increase stability of single-molecule junctions under bias, to pump energy into particular vibrational modes to perform current-induced reactions, or to increase the resolution in inelastic electron tunneling spectroscopy by controlling the life-times of phonons in a molecule by suppressing absorption and external dissipation processes. Under bias the current and the molecule exchange energy, which typically results in heating of the molecule. However, the opposite process is also possible, where energy is extracted from the molecule by the tunneling current. Designing a molecular "heat sink" where a particular vibrational mode funnels heat out of the molecule and into the leads would be very desirable. It is even possible to imagine how the vibrational energy of the other vibrational modes could be funneled into the "cooling mode," given the right molecular design. Previous efforts to understand heating and cooling mechanisms in single molecule junctions have primarily been concerned with small models, where it is unclear which molecular systems they correspond to. In this paper, our focus is on suppressing heating and obtaining current-induced cooling in certain vibrational modes. Strategies for cooling vibrational modes in single-molecule junctions are presented, together with atomistic calculations based on those strategies. Cooling and reduced heating are observed for two different cooling schemes in calculations of atomistic single-molecule junctions.

Simulated effect of pig-population density on epidemic size and choice of control strategy for classical swine fever epidemics in The Netherlands.

PubMed

Mangen, M-J J; Nielen, M; Burrell, A M

2002-12-18

We examined the importance of pig-population density in the area of an outbreak of classical swine fever (CSF) for the spread of the infection and the choice of control measures. A spatial, stochastic, dynamic epidemiological simulation model linked to a sector-level market-and-trade model for The Netherlands were used. Outbreaks in sparsely and densely populated areas were compared under four different control strategies and with two alternative trade assumptions. The obligatory control strategy required by current EU legislation was predicted to be enough to eradicate an epidemic starting in an area with sparse pig population. By contrast, additional control measures would be necessary if the outbreak began in an area with high pig density. The economic consequences of using preventive slaughter rather than emergency vaccination as an additional control measure depended strongly on the reactions of trading partners. Reducing the number of animal movements significantly reduced the size and length of epidemics in areas with high pig density. The phenomenon of carrier piglets was included in the model with realistic probabilities of infection by this route, but it made a negligible contribution to the spread of the infection.

40 CFR 52.777 - Control strategy: photochemical oxidants (hydrocarbons).

Code of Federal Regulations, 2013 CFR

2013-07-01

... lithography operations, business plastics, automotive plastics, and synthetic organic chemical manufacturing..., automotive plastics, and synthetic organic chemical manufacturing industries (SOCMI) batch processes... Michigan area, and an agreed order between U.S. Steel (currently USX Corporation) and the IDEM signed by...

40 CFR 52.777 - Control strategy: photochemical oxidants (hydrocarbons).

Code of Federal Regulations, 2014 CFR

2014-07-01

... plastics, automotive plastics, and synthetic organic chemical manufacturing industries (SOCMI) batch... wastewater processes, offset lithography operations, business plastics, automotive plastics, and synthetic... order between U.S. Steel (currently USX Corporation) and the IDEM signed by IDEM on March 22, 1996...

40 CFR 52.777 - Control strategy: photochemical oxidants (hydrocarbons).

Code of Federal Regulations, 2010 CFR

2010-07-01

... plastics, automotive plastics, and synthetic organic chemical manufacturing industries (SOCMI) batch... wastewater processes, offset lithography operations, business plastics, automotive plastics, and synthetic... order between U.S. Steel (currently USX Corporation) and the IDEM signed by IDEM on March 22, 1996...

40 CFR 52.777 - Control strategy: photochemical oxidants (hydrocarbons).

Code of Federal Regulations, 2011 CFR

2011-07-01

... plastics, automotive plastics, and synthetic organic chemical manufacturing industries (SOCMI) batch... wastewater processes, offset lithography operations, business plastics, automotive plastics, and synthetic... order between U.S. Steel (currently USX Corporation) and the IDEM signed by IDEM on March 22, 1996...

40 CFR 52.777 - Control strategy: photochemical oxidants (hydrocarbons).

Code of Federal Regulations, 2012 CFR

2012-07-01

... lithography operations, business plastics, automotive plastics, and synthetic organic chemical manufacturing..., automotive plastics, and synthetic organic chemical manufacturing industries (SOCMI) batch processes... Michigan area, and an agreed order between U.S. Steel (currently USX Corporation) and the IDEM signed by...

Hierarchical Fuzzy Control Applied to Parallel Connected UPS Inverters Using Average Current Sharing Scheme

NASA Astrophysics Data System (ADS)

Singh, Santosh Kumar; Ghatak Choudhuri, Sumit

2018-05-01

Parallel connection of UPS inverters to enhance power rating is a widely accepted practice. Inter-modular circulating currents appear when multiple inverter modules are connected in parallel to supply variable critical load. Interfacing of modules henceforth requires an intensive design, using proper control strategy. The potentiality of human intuitive Fuzzy Logic (FL) control with imprecise system model is well known and thus can be utilised in parallel-connected UPS systems. Conventional FL controller is computational intensive, especially with higher number of input variables. This paper proposes application of Hierarchical-Fuzzy Logic control for parallel connected Multi-modular inverters system for reduced computational burden on the processor for a given switching frequency. Simulated results in MATLAB environment and experimental verification using Texas TMS320F2812 DSP are included to demonstrate feasibility of the proposed control scheme.

Management strategies in pancreatic cancer.

PubMed

Campen, Christopher J; Dragovich, Tomislav; Baker, Amanda F

2011-04-01

Current first-line and adjuvant chemotherapeutic strategies for management of patients with pancreatic cancer are reviewed. Pancreatic adenocarcinoma is the 10th most prevalent cancer and the fourth most common cause of cancer deaths in the United States. More than 80% of patients with pancreatic cancer are diagnosed with locally advanced or metastatic disease and are not candidates for surgery; these patients often require multimodal treatment. The most widely used chemotherapy for such patients, as well as patients requiring adjuvant therapy after surgery, is gemcitabine or gemcitabine-based chemotherapy. All current chemotherapies for pancreatic cancer are associated with dose-limiting hematologic toxicity and other adverse effects that require ongoing monitoring and dosage adjustment to balance the benefits and risks of treatment. Pharmacists can play an important role in monitoring and providing drug information and guidance to patients and oncologists. Current investigational strategies include efforts to improve chemotherapy response rates and outcomes through modulation of cell signaling pathways and use of nanotechnology to improve drug delivery. Current management of pancreatic cancer is multifaceted, involving anticancer therapy, supportive care, and toxicity management. Standard systemic therapy with gemcitabine as a single agent or in combination with other cytotoxic agents provides modest benefits in terms of response and symptom control.

Multi-criteria decision making approaches for quality control of genome-wide association studies.

PubMed

Malovini, Alberto; Rognoni, Carla; Puca, Annibale; Bellazzi, Riccardo

2009-03-01

Experimental errors in the genotyping phases of a Genome-Wide Association Study (GWAS) can lead to false positive findings and to spurious associations. An appropriate quality control phase could minimize the effects of this kind of errors. Several filtering criteria can be used to perform quality control. Currently, no formal methods have been proposed for taking into account at the same time these criteria and the experimenter's preferences. In this paper we propose two strategies for setting appropriate genotyping rate thresholds for GWAS quality control. These two approaches are based on the Multi-Criteria Decision Making theory. We have applied our method on a real dataset composed by 734 individuals affected by Arterial Hypertension (AH) and 486 nonagenarians without history of AH. The proposed strategies appear to deal with GWAS quality control in a sound way, as they lead to rationalize and make explicit the experimenter's choices thus providing more reproducible results.

Evaluation of the anatomical site distribution of chlamydia and gonorrhoea in men who have sex with men and in high-risk women by routine testing: cross-sectional study revealing missed opportunities for treatment strategies.

PubMed

van Liere, Geneviève A F S; Hoebe, Christian J P A; Dukers-Muijrers, Nicole H T M

2014-02-01

Current strategies for controlling non-urogenital chlamydia and gonorrhoea are not uniform. It is assumed that present anorectal/oropharyngeal infections are coincidentally treated with urogenital infections. However, it is not clear whether this control strategy is effective. To inform current debate, we evaluated the anatomical site distribution of chlamydia and gonorrhoea by routine testing in men who have sex with men (hereafter men) and in high-risk women (prostitutes and swingers, hereafter women). Between January 2010 and November 2012, all men (n=2436) and women (n=1321) attending our sexually transmitted infection clinic were routinely tested for anorectal, oropharyngeal and urogenital Chlamydia trachomatis and Neisseria gonorrhoeae. Data were collected on demographics and sexual behaviour. Overall chlamydia positivity was 10.4% (254/2436) in men and 7.0% (92/1321) in women, for gonorrhoea this was 6.3% (154/2436) and 3.1% (41/1321), respectively. Isolated non-urogenital infections amounted to 76% of all infections in men and for up to 59% of all infections in women. For combined urogenital and anorectal infections, this amounted to 14% for men and up to 54% for women. Testing only for non-urogenital infections is insufficient, as it overlooks many infections. The use of coincidental treatment is therefore a suboptimal control strategy in high-risk groups for halting complications and transmission. There is an urgent need to optimise the testing guidelines for chlamydia and gonorrhoea at different anatomical sites.

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.

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

High precision locating control system based on VCM for Talbot lithography

NASA Astrophysics Data System (ADS)

Yao, Jingwei; Zhao, Lixin; Deng, Qian; Hu, Song

2016-10-01

Aiming at the high precision and efficiency requirements of Z-direction locating in Talbot lithography, a control system based on Voice Coil Motor (VCM) was designed. In this paper, we built a math model of VCM and its moving characteristic was analyzed. A double-closed loop control strategy including position loop and current loop were accomplished. The current loop was implemented by driver, in order to achieve the rapid follow of the system current. The position loop was completed by the digital signal processor (DSP) and the position feedback was achieved by high precision linear scales. Feed forward control and position feedback Proportion Integration Differentiation (PID) control were applied in order to compensate for dynamic lag and improve the response speed of the system. And the high precision and efficiency of the system were verified by simulation and experiments. The results demonstrated that the performance of Z-direction gantry was obviously improved, having high precision, quick responses, strong real-time and easily to expend for higher precision.

Mission Accomplished? We Need a Guide to the 'Post Release' World of Wolbachia for Aedes-borne Disease Control.

PubMed

Ritchie, Scott A; van den Hurk, Andrew F; Smout, Michael J; Staunton, Kyran M; Hoffmann, Ary A

2018-03-01

Historically, sustained control of Aedes aegypti, the vector of dengue, chikungunya, yellow fever, and Zika viruses, has been largely ineffective. Subsequently, two novel 'rear and release' control strategies utilizing mosquitoes infected with Wolbachia are currently being developed and deployed widely. In the incompatible insect technique, male Aedes mosquitoes, infected with Wolbachia, suppress populations through unproductive mating. In the transinfection strategy, both male and female Wolbachia-infected Ae. aegypti mosquitoes rapidly infect the wild population with Wolbachia, blocking virus transmission. It is critical to monitor the long-term stability of Wolbachia in host populations, and also the ability of this bacterium to continually inhibit virus transmission. Ongoing release and monitoring programs must be future-proofed should political support weaken when these vectors are successfully controlled. Copyright © 2017 Elsevier Ltd. All rights reserved.

Young and older adults' beliefs about effective ways to mitigate age-related memory decline.

PubMed

Horhota, Michelle; Lineweaver, Tara; Ositelu, Monique; Summers, Kristi; Hertzog, Christopher

2012-06-01

This study investigated whether young and older adults vary in their beliefs about the impact of various mitigating factors on age-related memory decline. Eighty young (ages 18-23) and 80 older (ages 60-82) participants reported their beliefs about their own memory abilities and the strategies that they use in their everyday lives to attempt to control their memory. Participants also reported their beliefs about memory change with age for hypothetical target individuals who were described as using (or not using) various means to mitigate memory decline. There were no age differences in personal beliefs about control over current or future memory ability. However, the two age groups differed in the types of strategies they used in their everyday life to control their memory. Young adults were more likely to use internal memory strategies, whereas older adults were more likely to focus on cognitive exercise and maintaining physical health as ways to optimize their memory ability. There were no age differences in rated memory change across the life span in hypothetical individuals. Both young and older adults perceived strategies related to improving physical and cognitive health as effective means of mitigating memory loss with age, whereas internal memory strategies were perceived as less effective means for controlling age-related memory decline. PsycINFO Database Record (c) 2012 APA, all rights reserved

Attentional deployment is not necessary for successful emotion regulation via cognitive reappraisal or expressive suppression.

PubMed

Bebko, Genna M; Franconeri, Steven L; Ochsner, Kevin N; Chiao, Joan Y

2014-06-01

According to appraisal theories of emotion, cognitive reappraisal is a successful emotion regulation strategy because it involves cognitively changing our thoughts, which, in turn, change our emotions. However, recent evidence has challenged the importance of cognitive change and, instead, has suggested that attentional deployment may at least partly explain the emotion regulation success of cognitive reappraisal. The purpose of the current study was to examine the causal relationship between attentional deployment and emotion regulation success. We examined 2 commonly used emotion regulation strategies--cognitive reappraisal and expressive suppression-because both depend on attention but have divergent behavioral, experiential, and physiological outcomes. Participants were either instructed to regulate emotions during free-viewing (unrestricted image viewing) or gaze-controlled (restricted image viewing) conditions and to self-report negative emotional experience. For both emotion regulation strategies, emotion regulation success was not altered by changes in participant control over the (a) direction of attention (free-viewing vs. gaze-controlled) during image viewing and (b) valence (negative vs. neutral) of visual stimuli viewed when gaze was controlled. Taken together, these findings provide convergent evidence that attentional deployment does not alter subjective negative emotional experience during either cognitive reappraisal or expressive suppression, suggesting that strategy-specific processes, such as cognitive appraisal and response modulation, respectively, may have a greater impact on emotional regulation success than processes common to both strategies, such as attention.

Use of near-infrared spectroscopy (NIRs) in the biopharmaceutical industry for real-time determination of critical process parameters and integration of advanced feedback control strategies using MIDUS control.

PubMed

Vann, Lucas; Sheppard, John

2017-12-01

Control of biopharmaceutical processes is critical to achieve consistent product quality. The most challenging unit operation to control is cell growth in bioreactors due to the exquisitely sensitive and complex nature of the cells that are converting raw materials into new cells and products. Current monitoring capabilities are increasing, however, the main challenge is now becoming the ability to use the data generated in an effective manner. There are a number of contributors to this challenge including integration of different monitoring systems as well as the functionality to perform data analytics in real-time to generate process knowledge and understanding. In addition, there is a lack of ability to easily generate strategies and close the loop to feedback into the process for advanced process control (APC). The current research aims to demonstrate the use of advanced monitoring tools along with data analytics to generate process understanding in an Escherichia coli fermentation process. NIR spectroscopy was used to measure glucose and critical amino acids in real-time to help in determining the root cause of failures associated with different lots of yeast extract. First, scale-down of the process was required to execute a simple design of experiment, followed by scale-up to build NIR models as well as soft sensors for advanced process control. In addition, the research demonstrates the potential for a novel platform technology that enables manufacturers to consistently achieve "goldenbatch" performance through monitoring, integration, data analytics, understanding, strategy design and control (MIDUS control). MIDUS control was employed to increase batch-to-batch consistency in final product titers, decrease the coefficient of variability from 8.49 to 1.16%, predict possible exhaust filter failures and close the loop to prevent their occurrence and avoid lost batches.

Protracted Counterinsurgency Chinese COIN Strategy in Xinjiang

DTIC Science & Technology

2008-05-22

does not display a currently valid OMB control number . PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 22-05-2008...2. REPORT TYPE Monograph 3. DATES COVERED (From - To) July 2007 – May 2008 5a. CONTRACT NUMBER 5b. GRANT NUMBER 4. TITLE AND SUBTITLE...Protracted Counterinsurgency: Chinese COIN Strategy in Xinjiang 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 6. AUTHOR(S

[Obstacle factors in implementation of integrated schistosomiasis prevention and control strategies with emphasis on infectious source in hilly endemic regions].

PubMed

Xu, Jia; Chen, Lin; Zhang, Yi; Wu, Jian-Jun; Wan, Xue-Xiang; Zhu, Rong; Xu, Hui-Rong; Liu, Qing; Huang, Liang; Wu, Zi-Song; Lu, Long-Ting; Zhong, Bo

2013-12-01

To analyze the main obstacles existing in the implementation of integrated schistosomiasis prevention and control strategies with emphasis on infection source in hilly endemic regions, and to find out the current priority issues in schistosomiasis prevention and control, so as to provide the evidence for further solutions. Two typical hilly schistosomiasis endemic regions in Sichuan Province, including Pujiang County of Chengdu City and Dongpo District of Meishan City, were selected as research areas. A framework of obstacle factors in the implementation of integrated schistosomiasis prevention and control strategies with emphasis on infectious source in hilly endemic regions was built by literature review, and the management and technical personnel who worked on schistosomiasis prevention and control in eight different industries (health, agriculture, forestry and so on) and five levels (provincial, city, county, township and village levels) were investigated by questionnaires in the way of nominal group. One hundred and fifty-three management and technical personnel in different industries and different levels were investigated. The questionnaire recovery rate (experts' positive coefficient) was 100%. The results showed that the first four problems needing to be concerned in the implementation of integrated schistosomiasis prevention and control strategies with emphasis on infection source were eliminating Oncomelania hupensis snails by projects, health education, examination and treatment for schistosomiasis persons, and harmless treatment of night-soil and safe water supply. The focuses of two counties in the implementation of integrated strategy measures were different. The harmless treatment of night-soil and safe water supply was the most important measure in Pujiang County, while the elimination of snails by projects was the most in Dong-po District. As the differences in the situation of epidemic areas and the existed condition of the prevention and treatment progress, the comprehensive schistosomiasis control measures should be adjusted according to the local conditions in the implementation of integrated schistosomiasis prevention and control strategies with emphasis on infection source.

IMPROVE AND APPLY CHEMICAL MECHANISMS FOR DEVELOPING OZONE CONTROL STRATEGIES

EPA Science Inventory

Air quality models that realistically describe the formation of ozone, air toxics, and other pollutants are needed by EPA and state agencies to predict current and future concentrations of these pollutants and develop ways to decrease their concentrations below harmful levels. ...

Fuzzy logic for plant-wide control of biological wastewater treatment process including greenhouse gas emissions.

PubMed

Santín, I; Barbu, M; Pedret, C; Vilanova, R

2018-06-01

The application of control strategies is increasingly used in wastewater treatment plants with the aim of improving effluent quality and reducing operating costs. Due to concerns about the progressive growth of greenhouse gas emissions (GHG), these are also currently being evaluated in wastewater treatment plants. The present article proposes a fuzzy controller for plant-wide control of the biological wastewater treatment process. Its design is based on 14 inputs and 6 outputs in order to reduce GHG emissions, nutrient concentration in the effluent and operational costs. The article explains and shows the effect of each one of the inputs and outputs of the fuzzy controller, as well as the relationship between them. Benchmark Simulation Model no 2 Gas is used for testing the proposed control strategy. The results of simulation results show that the fuzzy controller is able to reduce GHG emissions while improving, at the same time, the common criteria of effluent quality and operational costs. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Improved Control Strategy for Subsynchronous Resonance Mitigation with Fractional-order PI Controller

NASA Astrophysics Data System (ADS)

Raju, D. Koteswara; Umre, Bhimrao S.; Junghare, A. S.; Chitti Babu, B.

2016-12-01

This paper explores a robust Fractional-order PI (FOPI) controller to diminish Subsynchronous Resonance (SSR) using Static Synchronous series compensator (SSSC). The diminution of SSR is accomplished by increasing the network damping with the injection of voltage of subsynchronous component into the line at those frequencies which are proximate to the torsional mode frequency of the turbine-generator shaft. The voltage of subsynchronous frequency component is extracted from the transmission line and further the similar quantity of series voltage is injected by SSSC into the line to make the current of subsynchronous frequency component to zero which is the major source of oscillations in the turbine-generator shaft. The insertion and fine tuning of Fractional-order PI controller in the control scheme of SSSC the subsynchronous oscillations are reduced to 4 % as compared to conventional PI controller. The studied system is modelled and simulated using MATLAB-Simulink and the results are analysed to show the precision and robustness of the proposed control strategy.

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

PubMed Central

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

2015-01-01

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

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

PubMed

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

2014-01-01

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

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.

Perspectives on Strategies Using Swellable Polymers in Solid Dispersions for Controlled Drug Release.

PubMed

Tran, Thao T D; Tran, Phuong H L

2017-01-01

Poorly water-soluble drugs, which commonly face the issue of poor absorption and low bioavailability, have been under ongoing research of many formulation scientists for the past few decades. Solid dispersion is one of the most effective strategies in concerns for improving bioavailability of poorly water-soluble drugs. Either application of solid dispersions in dissolution enhancement of poorly water-soluble drugs or the use of swellable polymers in controlled drug release has been reported in pharmaceutical designs widely. However, a review of strategies of using swellable polymers in solid dispersion to take a full advantage of these polymers as a current perspective in facilitating drug bioavailability enhancement is still missing. In this review, we aim to provide a summary of techniques used to formulate a swellable polymer in solid dispersion especially a description of a suitable fabrication method in design of a controlled release solid dispersion. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Architectures for mission control at the Jet Propulsion Laboratory

NASA Technical Reports Server (NTRS)

Davidson, Reger A.; Murphy, Susan C.

1992-01-01

JPL is currently converting to an innovative control center data system which is a distributed, open architecture for telemetry delivery and which is enabling advancement towards improved automation and operability, as well as new technology, in mission operations at JPL. The scope of mission control within mission operations is examined. The concepts of a mission control center and how operability can affect the design of a control center data system are discussed. Examples of JPL's mission control architecture, data system development, and prototype efforts at the JPL Operations Engineering Laboratory are provided. Strategies for the future of mission control architectures are outlined.

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

Assessment of the effect of larval source management and house improvement on malaria transmission when added to standard malaria control strategies in southern Malawi: study protocol for a cluster-randomised controlled trial.

PubMed

McCann, Robert S; van den Berg, Henk; Diggle, Peter J; van Vugt, Michèle; Terlouw, Dianne J; Phiri, Kamija S; Di Pasquale, Aurelio; Maire, Nicolas; Gowelo, Steven; Mburu, Monicah M; Kabaghe, Alinune N; Mzilahowa, Themba; Chipeta, Michael G; Takken, Willem

2017-09-22

Due to outdoor and residual transmission and insecticide resistance, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) will be insufficient as stand-alone malaria vector control interventions in many settings as programmes shift toward malaria elimination. Combining additional vector control interventions as part of an integrated strategy would potentially overcome these challenges. Larval source management (LSM) and structural house improvements (HI) are appealing as additional components of an integrated vector management plan because of their long histories of use, evidence on effectiveness in appropriate settings, and unique modes of action compared to LLINs and IRS. Implementation of LSM and HI through a community-based approach could provide a path for rolling-out these interventions sustainably and on a large scale. We will implement community-based LSM and HI, as additional interventions to the current national malaria control strategies, using a randomised block, 2 × 2 factorial, cluster-randomised design in rural, southern Malawi. These interventions will be continued for two years. The trial catchment area covers about 25,000 people living in 65 villages. Community participation is encouraged by training community volunteers as health animators, and supporting the organisation of village-level committees in collaboration with The Hunger Project, a non-governmental organisation. Household-level cross-sectional surveys, including parasitological and entomological sampling, will be conducted on a rolling, 2-monthly schedule to measure outcomes over two years (2016 to 2018). Coverage of LSM and HI will also be assessed throughout the trial area. Combining LSM and/or HI together with the interventions currently implemented by the Malawi National Malaria Control Programme is anticipated to reduce malaria transmission below the level reached by current interventions alone. Implementation of LSM and HI through a community-based approach provides an opportunity for optimum adaptation to the local ecological and social setting, and enhances the potential for sustainability. Registered with The Pan African Clinical Trials Registry on 3 March 2016, trial number PACTR201604001501493.

Mood repair via attention refocusing or recall of positive autobiographical memories by adolescents with pediatric-onset major depression.

PubMed

Kovacs, Maria; Yaroslavsky, Ilya; Rottenberg, Jonathan; George, Charles J; Baji, Ildikó; Benák, István; Dochnal, Roberta; Halas, Kitti; Kiss, Enikő; Vetró, Ágnes; Kapornai, Krisztina

2015-10-01

Impaired emotion regulation is increasingly recognized as a core feature of depressive disorders. Indeed, currently and previously depressed adults both report greater problems in attenuating sadness (mood repair) in daily life than healthy controls. In contrast, studies of various strategies to attenuate sad affect have mostly found that currently or previously depressed adults and controls were similarly successful at mood repair in the laboratory. But few studies have examined mood repair among depression-prone youths or the effects of trait characteristics on mood repair outcomes in the laboratory. Adolescents, whose first episode of major depressive disorder (MDD) had onset at age 9, on average (probands), and were either in remission or depressed, and control peers, watched a sad film clip. Then, they were instructed to engage in refocusing attention (distraction) or recalling happy memories. Using affect ratings provided by the youths, we tested two developmentally informed hypotheses about whether the subject groups would be similarly able to attenuate sadness via the two mood repair strategies. We also explored if self-reported habitual (trait) mood repair influenced laboratory performance. Contrary to expectations, attention refocusing and recall of happy memories led to comparable mood benefits across subjects. Control adolescents reported significantly greater reductions in sadness than did depressed (Cohen's d = .48) or remitted (Cohen's d = .32) probands, regardless of mood repair strategy, while currently depressed probands remained the saddest after mood repair. Habitual mood repair styles moderated the effects of instructed (state) mood repair in the laboratory. Whether depressed or in remission, adolescents with MDD histories are not as efficient at mood repair in the laboratory as controls. But proband-control group differences in mood repair outcomes were modest in scope, suggesting that the abilities that subserve affect regulation have been preserved in probands to some degree. Further information about the nature of mood repair problems among youths with depression histories would help to better understand the clinical course of MDD and to design personalized interventions for depression. © 2015 Association for Child and Adolescent Mental Health.

Mood repair via attention refocusing or recall of positive autobiographical memories by adolescents with pediatric onset major depression

PubMed Central

Kovacs, Maria; Yaroslavsky, Ilya; Rottenberg, Jonathan; George, Charles J.; Baji, Ildikó; Benák, István; Dochnal, Roberta; Halas, Kitti; Kiss, Enikő; Vetró, Ágnes; Kapornai, Krisztina

2014-01-01

Background Impaired emotion regulation is increasingly recognized as a core feature of depressive disorders. Indeed, currently and previously depressed adults both report greater problems in attenuating sadness (mood repair) in daily life than healthy controls. In contrast, studies of various strategies to attenuate sad affect have mostly found that currently or previously depressed adults and controls were similarly successful at mood repair in the laboratory. But few studies have examined mood repair among depression-prone youths or the effects of trait characteristics on mood repair outcomes in the laboratory. Methods Adolescents, whose first episode of major depressive disorder (MDD) had onset at age 9, on average (probands), and were either in remission or depressed, and control peers, watched a sad film clip. Then, they were instructed to engage in re-focusing attention (distraction) or recalling happy memories. Using affect ratings provided by the youths, we tested two developmentally informed hypotheses about whether the subject groups would be similarly able to attenuate sadness via the two mood repair strategies. We also explored if self-reported habitual (trait) mood repair influenced laboratory performance. Results Contrary to expectations, attention re-focusing and recall of happy memories led to comparable mood benefits across subjects. Control adolescents reported significantly greater reductions in sadness than did depressed (Cohen’s d=.48) or remitted (Cohen’s d=.32) probands, regardless of mood repair strategy, while currently depressed probands remained the saddest after mood repair. Habitual mood repair styles moderated the effects of instructed (state) mood repair in the laboratory. Conclusions Whether depressed or in remission, adolescents with MDD histories are not as efficient at mood repair in the laboratory as controls. But proband-control group differences in mood repair outcomes were modest in scope, suggesting that the abilities that subserve affect regulation have been preserved in probands to some degree. Further information about the nature of mood repair problems among youths with depression histories would help to better understand the clinical course of MDD and to design personalized interventions for depression. PMID:25557229

Heterogeneity of Environments Associated with Transmission of Visceral Leishmaniasis in South-Eastern France and Implication for Control Strategies

PubMed Central

Faucher, Benoit; Gaudart, Jean; Faraut, Francoise; Pomares, Christelle; Mary, Charles; Marty, Pierre; Piarroux, Renaud

2012-01-01

Background Visceral leishmaniasis due to Leishmania infantum is currently spreading into new foci across Europe. Leishmania infantum transmission in the Old World was reported to be strongly associated with a few specific environments. Environmental changes due to global warming or human activity were therefore incriminated in the spread of the disease. However, comprehensive studies were lacking to reliably identify all the environments at risk and thereby optimize monitoring and control strategy. Methodology/Findings We exhaustively collected 328 cases of autochthonous visceral leishmaniasis from 1993 to 2009 in South-Eastern France. Leishmaniasis incidence decreased from 31 yearly cases between 1993 and 1997 to 12 yearly cases between 2005 and 2009 mostly because Leishmania/HIV coinfection were less frequent. No spread of human visceral leishmaniasis was observed in the studied region. Two major foci were identified, associated with opposite environments: whereas one involved semi-rural hillside environments partly made of mixed forests, the other involved urban and peri-urban areas in and around the region main town, Marseille. The two neighboring foci were related to differing environments despite similar vectors (P. perniciosus), canine reservoir, parasite (L. infantum zymodeme MON-1), and human host. Conclusions/Significance This unprecedented collection of cases highlighted the occurrence of protracted urban transmission of L. infantum in France, a worrisome finding as the disease is currently spreading in other areas around the Mediterranean. These results complete previous studies about more widespread canine leishmaniasis or human asymptomatic carriage. This first application of systematic geostatistical methods to European human visceral leishmaniasis demonstrated an unsuspected heterogeneity of environments associated with the transmission of the disease. These findings modify the current view of leishmaniasis epidemiology. They notably stress the need for locally defined control strategies and extensive monitoring including in urban environments. PMID:22880142

A Systematic Review of Tobacco Smoking Prevalence and Description of Tobacco Control Strategies in Sub-Saharan African Countries; 2007 to 2014.

PubMed

Brathwaite, Rachel; Addo, Juliet; Smeeth, Liam; Lock, Karen

2015-01-01

To systematically review current smoking prevalence among adults in sub-Saharan Africa from 2007 to May 2014 and to describe the context of tobacco control strategies in these countries. Five databases, Medline, Embase, Africa-wide Information, Cinahl Plus, and Global Health were searched using a systematic search strategy. There were no language restrictions. 26 included studies measured current smoking prevalence in nationally representative adult populations in sub-Saharan African countries. Study details were independently extracted using a standard datasheet. Data on tobacco control policies, taxation and trends in prices were obtained from the Implementation Database of the WHO FCTC website. Studies represented 13 countries. Current smoking prevalence varied widely ranging from 1.8% in Zambia to 25.8% in Sierra Leone. The prevalence of smoking was consistently lower in women compared to men with the widest gender difference observed in Malawi (men 25.9%, women 2.9%). Rwanda had the highest prevalence of women smokers (12.6%) and Ghana had the lowest (0.2%). Rural, urban patterns were inconsistent. Most countries have implemented demand-reduction measures including bans on advertising, and taxation rates but to different extents. Smoking prevalence varied widely across sub-Saharan Africa, even between similar country regions, but was always higher in men. High smoking rates were observed among countries in the eastern and southern regions of Africa, mainly among men in Ethiopia, Malawi, Rwanda, and Zambia and women in Rwanda and rural Zambia. Effective action to reduce smoking across sub-Saharan Africa, particularly targeting population groups at increased risk remains a pressing public health priority.

Heterogeneity of environments associated with transmission of visceral leishmaniasis in South-Eastern France and implication for control strategies.

PubMed

Faucher, Benoit; Gaudart, Jean; Faraut, Francoise; Pomares, Christelle; Mary, Charles; Marty, Pierre; Piarroux, Renaud

2012-01-01

Visceral leishmaniasis due to Leishmania infantum is currently spreading into new foci across Europe. Leishmania infantum transmission in the Old World was reported to be strongly associated with a few specific environments. Environmental changes due to global warming or human activity were therefore incriminated in the spread of the disease. However, comprehensive studies were lacking to reliably identify all the environments at risk and thereby optimize monitoring and control strategy. We exhaustively collected 328 cases of autochthonous visceral leishmaniasis from 1993 to 2009 in South-Eastern France. Leishmaniasis incidence decreased from 31 yearly cases between 1993 and 1997 to 12 yearly cases between 2005 and 2009 mostly because Leishmania/HIV coinfection were less frequent. No spread of human visceral leishmaniasis was observed in the studied region. Two major foci were identified, associated with opposite environments: whereas one involved semi-rural hillside environments partly made of mixed forests, the other involved urban and peri-urban areas in and around the region main town, Marseille. The two neighboring foci were related to differing environments despite similar vectors (P. perniciosus), canine reservoir, parasite (L. infantum zymodeme MON-1), and human host. This unprecedented collection of cases highlighted the occurrence of protracted urban transmission of L. infantum in France, a worrisome finding as the disease is currently spreading in other areas around the Mediterranean. These results complete previous studies about more widespread canine leishmaniasis or human asymptomatic carriage. This first application of systematic geostatistical methods to European human visceral leishmaniasis demonstrated an unsuspected heterogeneity of environments associated with the transmission of the disease. These findings modify the current view of leishmaniasis epidemiology. They notably stress the need for locally defined control strategies and extensive monitoring including in urban environments.

Periarticular regional analgesia in total knee arthroplasty: a review of the neuroanatomy and injection technique.

PubMed

Guild, George N; Galindo, Rubin P; Marino, Joseph; Cushner, Fred D; Scuderi, Giles R

2015-01-01

Postoperative pain control after total knee arthroplasty may be insufficient, resulting in insomnia, antalgic ambulation, and difficulty with rehabilitation. Current strategies, including the use of femoral nerve catheters, may control pain but have been associated with falls, motor blockade, and quadriceps inhibition. Periarticular infiltration using the appropriate technique and knowledge of intraarticular knee anatomy may increase pain control and maximize rehabilitation. Copyright © 2015 Elsevier Inc. All rights reserved.

Field Balancing and Harmonic Vibration Suppression in Rigid AMB-Rotor Systems with Rotor Imbalances and Sensor Runout.

PubMed

Xu, Xiangbo; Chen, Shao

2015-08-31

Harmonic vibrations of high-speed rotors in momentum exchange devices are primary disturbances for attitude control of spacecraft. Active magnetic bearings (AMBs), offering the ability to control the AMB-rotor dynamic behaviors, are preferred in high-precision and micro-vibration applications, such as high-solution Earth observation satellites. However, undesirable harmonic displacements, currents, and vibrations also occur in the AMB-rotor system owing to the mixed rotor imbalances and sensor runout. To compensate the rotor imbalances and to suppress the harmonic vibrations, two control methods are presented. Firstly, a four degrees-of-freedom AMB-rotor model with the static imbalance, dynamic imbalance, and the sensor runout are described. Next, a synchronous current reduction approach with a variable-phase notch feedback is proposed, so that the rotor imbalances can be identified on-line through the analysis of the synchronous displacement relationships of the geometric, inertial, and rotational axes of the rotor. Then, the identified rotor imbalances, which can be represented at two prescribed balancing planes of the rotor, are compensated by discrete add-on weights whose masses are calculated in the vector form. Finally, a repetitive control algorithm is utilized to suppress the residual harmonic vibrations. The proposed field balancing and harmonic vibration suppression strategies are verified by simulations and experiments performed on a control moment gyro test rig with a rigid AMB-rotor system. Compared with existing methods, the proposed strategies do not require trial weights or an accurate model of the AMB-rotor system. Moreover, the harmonic displacements, currents, and vibrations can be well-attenuated simultaneously.

Field Balancing and Harmonic Vibration Suppression in Rigid AMB-Rotor Systems with Rotor Imbalances and Sensor Runout

PubMed Central

Xu, Xiangbo; Chen, Shao

2015-01-01

Harmonic vibrations of high-speed rotors in momentum exchange devices are primary disturbances for attitude control of spacecraft. Active magnetic bearings (AMBs), offering the ability to control the AMB-rotor dynamic behaviors, are preferred in high-precision and micro-vibration applications, such as high-solution Earth observation satellites. However, undesirable harmonic displacements, currents, and vibrations also occur in the AMB-rotor system owing to the mixed rotor imbalances and sensor runout. To compensate the rotor imbalances and to suppress the harmonic vibrations, two control methods are presented. Firstly, a four degrees-of-freedom AMB-rotor model with the static imbalance, dynamic imbalance, and the sensor runout are described. Next, a synchronous current reduction approach with a variable-phase notch feedback is proposed, so that the rotor imbalances can be identified on-line through the analysis of the synchronous displacement relationships of the geometric, inertial, and rotational axes of the rotor. Then, the identified rotor imbalances, which can be represented at two prescribed balancing planes of the rotor, are compensated by discrete add-on weights whose masses are calculated in the vector form. Finally, a repetitive control algorithm is utilized to suppress the residual harmonic vibrations. The proposed field balancing and harmonic vibration suppression strategies are verified by simulations and experiments performed on a control moment gyro test rig with a rigid AMB-rotor system. Compared with existing methods, the proposed strategies do not require trial weights or an accurate model of the AMB-rotor system. Moreover, the harmonic displacements, currents, and vibrations can be well-attenuated simultaneously. PMID:26334281

Control Strategies for Drug Product Continuous Direct Compression-State of Control, Product Collection Strategies, and Startup/Shutdown Operations for the Production of Clinical Trial Materials and Commercial Products.

PubMed

Almaya, Ahmad; De Belder, Lawrence; Meyer, Robert; Nagapudi, Karthik; Lin, Hung-Ren Homer; Leavesley, Ian; Jayanth, Jayanthy; Bajwa, Gurjit; DiNunzio, James; Tantuccio, Anthony; Blackwood, Dan; Abebe, Admassu

2017-04-01

Continuous manufacturing (CM) has emerged in the pharmaceutical industry as a paradigm shift with significant advantages related to cost, efficiency, flexibility, and higher assurance of quality. The inherent differences from batch processes justify examining the CM control strategy more holistically. This article describes the current thinking for the control and implementation of CM, using the example of a direct compression process and taking into consideration the ICH Q10 definition of "state of control" and process validation requirements. Statistical process control using control charts, sources of variation, process capability, and process performance is explained as a useful concept that can help assess the impact of variation within a batch and indicates if a process is in state of control. The potential for time-variant nature of startup and shutdown with CM is discussed to assure product quality while minimizing waste as well as different options for detection and isolation of non-conforming materials due to process upsets. While different levels of control are possible with CM, an appropriate balance between process control and end product testing is needed depending on the level of process understanding at the different stages of development from the production of clinical supplies through commercialization. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

A new adaptive control strategy for a class of nonlinear system using RBF neuro-sliding-mode technique: application to SEIG wind turbine control system

NASA Astrophysics Data System (ADS)

Kenné, Godpromesse; Fotso, Armel Simo; Lamnabhi-Lagarrigue, Françoise

2017-04-01

In this paper, a new hybrid method which combines radial basis function (RBF) neural network with a sliding-mode technique to take advantage of their common features is used to control a class of nonlinear systems. A real-time dynamic nonlinear learning law of the weight vector is synthesized and the closed-loop stability has been demonstrated using Lyapunov theory. The solution presented in this work does not need the knowledge of the perturbation bounds, neither the knowledge of the full state of the nonlinear system. In addition, the bounds of the nonlinear functions are assumed to be unknown and the proposed RBF structure uses reduced number of hidden units. This hybrid control strategy is applied to extract the maximum available energy from a stand-alone self-excited variable low-wind speed energy conversion system and design the dc-voltage and rotor flux controllers as well as the load-side frequency and voltage regulators assuming that the measured outputs are the rotor speed, stator currents, load-side currents and voltages despite large variation of the rotor resistance and uncertainties on the inductances. Finally, simulation results compared with those obtained using the well-known second-order sliding-mode controller are given to show the effectiveness and feasibility of the proposed approach.

Systematic review of management strategies to control chronic wasting disease in wild deer populations in North America.

PubMed

Uehlinger, F D; Johnston, A C; Bollinger, T K; Waldner, C L

2016-08-22

Chronic wasting disease (CWD) is a contagious, fatal prion disease affecting cervids in a growing number of regions across North America. Projected deer population declines and concern about potential spread of CWD to other species warrant strategies to manage this disease. Control efforts to date have been largely unsuccessful, resulting in continuing spread and increasing prevalence. This systematic review summarizes peer-reviewed published reports describing field-applicable CWD control strategies in wild deer populations in North America using systematic review methods. Ten databases were searched for peer-reviewed literature. Following deduplication, relevance screening, full-text appraisal, subject matter expert review and qualitative data extraction, nine references were included describing four distinct management strategies. Six of the nine studies used predictive modeling to evaluate control strategies. All six demonstrated one or more interventions to be effective but results were dependant on parameters and assumptions used in the model. Three found preferential removal of CWD infected deer to be effective in reducing CWD prevalence; one model evaluated a test and slaughter strategy, the other selective removal of infected deer by predators and the third evaluated increased harvest of the sex with highest prevalence (males). Three models evaluated non-selective harvest of deer. There were only three reports that examined primary data collected as part of observational studies. Two of these studies supported the effectiveness of intensive non-selective culling; the third study did not find a difference between areas that were subjected to culling and those that were not. Seven of the nine studies were conducted in the United States. This review highlights the paucity of evaluated, field-applicable control strategies for CWD in wild deer populations. Knowledge gaps in the complex epidemiology of CWD and the intricacies inherent to prion diseases currently pose significant challenges to effective control of this disease in wild deer in North America.

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.

Is reconstruction the best management strategy for anterior cruciate ligament rupture? A systematic review and meta-analysis comparing anterior cruciate ligament reconstruction versus non-operative treatment.

PubMed

Smith, T O; Postle, K; Penny, F; McNamara, I; Mann, C J V

2014-03-01

The purpose of this study was to determine the optimal clinical and cost-effective strategy for managing people following ACL rupture. A systematic review of the published (AMED, CINAHL, MEDLINE, EMBASE, PubMed, psycINFO and the Cochrane Library) and unpublished literature (OpenGrey, the WHO International Clinical Trials Registry Platform, Current Controlled Trials and the UK National Research Register Archive) was conducted on April 2013. All randomised and non-randomised controlled trials evaluating clinical or health economic outcomes of isolated ligament reconstruction versus non-surgical management following ACL rupture were included. Methodological quality was assessed using the PEDro appraisal tool. When appropriate, meta-analysis was conducted to pool data. From a total of 943 citations, sixteen studies met the eligibility criteria. These included 1397 participants, 825 who received ACL reconstruction versus 592 who were managed non-surgically. The methodological quality of the literature was poor. The findings indicated that whilst reconstructed ACL offers significantly greater objective tibiofemoral stability (p<0.001), there appears limited evidence to suggest a superiority between reconstruction versus non-surgical management in functional outcomes. There was a small difference between the management strategies in respect to the development of osteoarthritis during the initial 20 years following index management strategy (Odds Ratio 1.56; p=0.05). The current literature is insufficient to base clinical decision-making with respect to treatment opinions for people following ACL rupture. Whilst based on a poor evidence, the current evidence would indicate that people following ACL rupture should receive non-operative interventions before surgical intervention is considered. © 2013.

A Maximum Power Point Tracking Control Method of a Photovoltaic Power Generator with Consideration of Dynamic Characteristics of Solar Cells

NASA Astrophysics Data System (ADS)

Watanabe, Takashi; Yoshida, Toshiya; Ohniwa, Katsumi

This paper discusses a new control strategy for photovoltaic power generation systems with consideration of dynamic characteristics of the photovoltaic cells. The controller estimates internal currents of an equivalent circuit for the cells. This estimated, or the virtual current and the actual voltage of the cells are fed to a conventional Maximum-Power-Point-Tracking (MPPT) controller. Consequently, this MPPT controller still tracks the optimum point even though it is so designed that the seeking speed of the operating point is extremely high. This system may suit for applications, which are installed in rapidly changeable insolation and temperature-conditions e.g. automobiles, trains, and airplanes. The proposed method is verified by experiment with a combination of this estimating function and the modified Boehringer's MPPT algorithm.

A Conserved Bicycle Model for Circadian Clock Control of Membrane Excitability

PubMed Central

Flourakis, Matthieu; Kula-Eversole, Elzbieta; Hutchison, Alan L.; Han, Tae Hee; Aranda, Kimberly; Moose, Devon L.; White, Kevin P.; Dinner, Aaron R.; Lear, Bridget C.; Ren, Dejian; Diekman, Casey O.; Raman, Indira M.; Allada, Ravi

2015-01-01

Summary Circadian clocks regulate membrane excitability in master pacemaker neurons to control daily rhythms of sleep and wake. Here we find that two distinctly timed electrical drives collaborate to impose rhythmicity on Drosophila clock neurons. In the morning, a voltage-independent sodium conductance via the NA/NALCN ion channel depolarizes these neurons. This current is driven by the rhythmic expression of NCA localization factor-1, linking the molecular clock to ion channel function. In the evening, basal potassium currents peak to silence clock neurons. Remarkably, daily antiphase cycles of sodium and potassium currents also drive mouse clock neuron rhythms. Thus, we reveal an evolutionarily ancient strategy for the neural mechanisms that govern daily sleep and wake. PMID:26276633

Current vector control challenges in the fight against malaria.

PubMed

Benelli, Giovanni; Beier, John C

2017-10-01

The effective and eco-friendly control of Anopheles vectors plays a key role in any malaria management program. Integrated Vector Management (IVM) suggests making use of the full range of vector control tools available. The strategies for IVM require novel technologies to control outdoor transmission of malaria. Despite the wide number of promising control tools tested against mosquitoes, current strategies for malaria vector control used in most African countries are not sufficient to achieve successful malaria control. The majority of National Malaria Control Programs in Africa still rely on indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs). These methods reduce malaria incidence but generally have little impact on malaria prevalence. In addition to outdoor transmission, growing levels of insecticide resistance in targeted vectors threaten the efficacy of LLINs and IRS. Larvicidal treatments can be useful, but are not recommended for rural areas. The research needed to improve the quality and delivery of mosquito vector control should focus on (i) optimization of processes and methods for vector control delivery; (ii) monitoring of vector populations and biting activity with reliable techniques; (iii) the development of effective and eco-friendly tools to reduce the burden or locally eliminate malaria and other mosquito-borne diseases; (iv) the careful evaluation of field suitability and efficacy of new mosquito control tools to prove their epidemiological impact; (v) the continuous monitoring of environmental changes which potentially affect malaria vector populations; (vi) the cooperation among different disciplines, with main emphasis on parasitology, tropical medicine, ecology, entomology, and ecotoxicology. A better understanding of behavioral ecology of malaria vectors is required. Key ecological obstacles that limit the effectiveness of vector control include the variation in mosquito behavior, development of insecticide resistance, presence of behavioral avoidance, high vector biodiversity, competitive and food web interactions, lack of insights on mosquito dispersal and mating behavior, and the impact of environmental changes on mosquito ecological traits. Overall, the trans-disciplinary cooperation among parasitologists and entomologists is crucial to ensure proper evaluation of the epidemiological impact triggered by novel mosquito vector control strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

Upgrade of a GEP50 robot control system

NASA Astrophysics Data System (ADS)

Alounai, Ali T.; Gharsalli, Imed

2000-03-01

Recently the ASL at Tennessee Technological University was donated a GEP50 welder. The welding is done via off line point-to-point teaching. A state of the art robot was needed for research but because money was not available to purchase such an expensive item. It was therefore decided to upgrade the GEP50 control system to make the welder a multitasking robot. The robot has five degrees of freedom can be sufficient to pursue some research in robotics control. The problem was that the control system of the welder is limited to point-to-point control, using off-line teaching. To make the GEP50 a multitasking robot that can be controlled using different control strategies, the existing control system of the welder had to be replaced. The upgrade turned to be a low cost operation. This robot is currently in sue to test different advanced control strategies in the ASL. This work discusses all the steps and tasks undertaken during the upgrade operation. The hardware and software required or the upgrade are provided in this paper. The newly developed control system has been implemented and tested successfully.

Proteomic analysis of Mycoplasma gallisepticum vaccine strain F

USDA-ARS?s Scientific Manuscript database

The persistence and displacement abilities of the Mycoplasma gallisepticum vaccine strain F (F-strain) are well documented. Understanding the mechanism(s) of colonization and persistence of F-strain will aid in the current intervention strategies to diagnose and control MG infections in poultry. In ...

An Experimental Investigation of Cognitive Defusion

ERIC Educational Resources Information Center

Pilecki, Brian C.; McKay, Dean

2012-01-01

The current study compared cognitive defusion with other strategies in reducing the impact of experimentally induced negative emotional states. Sixty-seven undergraduates were assigned to one of three conditions (cognitive defusion, thought suppression, or control) and instructed in standardized approaches relevant to each condition before viewing…

Workgroup Report: Public Health Strategies for Reducing Aflatoxin Exposure in Developing Countries

PubMed Central

Strosnider, Heather; Azziz-Baumgartner, Eduardo; Banziger, Marianne; Bhat, Ramesh V.; Breiman, Robert; Brune, Marie-Noel; DeCock, Kevin; Dilley, Abby; Groopman, John; Hell, Kerstin; Henry, Sara H.; Jeffers, Daniel; Jolly, Curtis; Jolly, Pauline; Kibata, Gilbert N.; Lewis, Lauren; Liu, Xiumei; Luber, George; McCoy, Leslie; Mensah, Patience; Miraglia, Marina; Misore, Ambrose; Njapau, Henry; Ong, Choon-Nam; Onsongo, Mary T.K.; Page, Samuel W.; Park, Douglas; Patel, Manish; Phillips, Timothy; Pineiro, Maya; Pronczuk, Jenny; Rogers, Helen Schurz; Rubin, Carol; Sabino, Myrna; Schaafsma, Arthur; Shephard, Gordon; Stroka, Joerg; Wild, Christopher; Williams, Jonathan T.; Wilson, David

2006-01-01

Consecutive outbreaks of acute aflatoxicosis in Kenya in 2004 and 2005 caused > 150 deaths. In response, the Centers for Disease Control and Prevention and the World Health Organization convened a workgroup of international experts and health officials in Geneva, Switzerland, in July 2005. After discussions concerning what is known about aflatoxins, the workgroup identified gaps in current knowledge about acute and chronic human health effects of aflatoxins, surveillance and food monitoring, analytic methods, and the efficacy of intervention strategies. The workgroup also identified public health strategies that could be integrated with current agricultural approaches to resolve gaps in current knowledge and ultimately reduce morbidity and mortality associated with the consumption of aflatoxin-contaminated food in the developing world. Four issues that warrant immediate attention were identified: a) quantify the human health impacts and the burden of disease due to aflatoxin exposure; b) compile an inventory, evaluate the efficacy, and disseminate results of ongoing intervention strategies; c) develop and augment the disease surveillance, food monitoring, laboratory, and public health response capacity of affected regions; and d) develop a response protocol that can be used in the event of an outbreak of acute aflatoxicosis. This report expands on the workgroup’s discussions concerning aflatoxin in developing countries and summarizes the findings. PMID:17185282

Chaotic Dynamics of a Josephson Junction with a Ratchet Potential and Current-Modulating Damping

NASA Astrophysics Data System (ADS)

Li, Fei; Li, Wenwu; Xu, Lan

2018-06-01

The chaotic dynamics of a Josephson junction with a ratchet potential and current-modulating damping are studied. Under the first-order approximation, we construct the general solution of the first-order equation whose boundedness condition contains the famous Melnikov chaotic criterion. Based on the general solution, the incomputability and unpredictability of the system's chaotic behavior are discussed. For the case beyond perturbation conditions, the evolution of stroboscopic Poincaré sections shows that the system undergoes a quasi-periodic transition to chaos with an increasing intensity of the rf-current. Through a suitable feedback controlling strategy, the chaos can be effectively suppressed and the intensity of the controller can vary in a large range. It is also found that the current between the two separated superconductors increases monotonously in some specific parameter spaces.

Chaotic Dynamics of a Josephson Junction with a Ratchet Potential and Current-Modulating Damping

NASA Astrophysics Data System (ADS)

Li, Fei; Li, Wenwu; Xu, Lan

2018-04-01

The chaotic dynamics of a Josephson junction with a ratchet potential and current-modulating damping are studied. Under the first-order approximation, we construct the general solution of the first-order equation whose boundedness condition contains the famous Melnikov chaotic criterion. Based on the general solution, the incomputability and unpredictability of the system's chaotic behavior are discussed. For the case beyond perturbation conditions, the evolution of stroboscopic Poincaré sections shows that the system undergoes a quasi-periodic transition to chaos with an increasing intensity of the rf-current. Through a suitable feedback controlling strategy, the chaos can be effectively suppressed and the intensity of the controller can vary in a large range. It is also found that the current between the two separated superconductors increases monotonously in some specific parameter spaces.

The host immune response to gastrointestinal nematode infection in sheep.

PubMed

McRae, K M; Stear, M J; Good, B; Keane, O M

2015-12-01

Gastrointestinal nematode infection represents a major threat to the health, welfare and productivity of sheep populations worldwide. Infected lambs have a reduced ability to absorb nutrients from the gastrointestinal tract, resulting in morbidity and occasional mortality. The current chemo-dominant approach to nematode control is considered unsustainable due to the increasing incidence of anthelmintic resistance. In addition, there is growing consumer demand for food products from animals not subjected to chemical treatment. Future mechanisms of nematode control must rely on alternative, sustainable strategies such as vaccination or selective breeding of resistant animals. Such strategies take advantage of the host's natural immune response to nematodes. The ability to resist gastrointestinal nematode infection is considered to be dependent on the development of a protective acquired immune response, although the precise immune mechanisms involved in initiating this process remain to be fully elucidated. In this study, current knowledge on the innate and acquired host immune response to gastrointestinal nematode infection in sheep and the development of immunity is reviewed. © 2015 John Wiley & Sons Ltd.

A paradigm shift on beta-thalassaemia treatment: How will we manage this old disease with new therapies?

PubMed

Cappellini, Maria Domenica; Porter, John B; Viprakasit, Vip; Taher, Ali T

2018-07-01

Beta-thalassaemia causes defective haemoglobin synthesis leading to ineffective erythropoiesis, chronic haemolytic anaemia, and subsequent clinical complications. Blood transfusion and iron chelation allow long-term disease control, and haematopoietic stem cell transplantation offers a potential cure for some patients. Nonetheless, there are still many challenges in the management of beta-thalassaemia. The main treatment option for most patients is supportive care; furthermore, the long-term efficacy and safety of current therapeutic strategies are limited and adherence is suboptimal. An increasing understanding of the underlying molecular and cellular disease mechanisms plus an awareness of limitations of current management strategies are driving research into novel therapeutic options. Here we provide an overview of the current pathophysiology, clinical manifestations, and global burden of beta-thalassaemia. We reflect on what has been achieved to date, describe the challenges associated with currently available therapy, and discuss how these issues might be addressed by novel therapeutic approaches in development. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

A literature review of economic evaluations for a neglected tropical disease: human African trypanosomiasis ("sleeping sickness").

PubMed

Sutherland, C Simone; Yukich, Joshua; Goeree, Ron; Tediosi, Fabrizio

2015-02-01

Human African trypanosomiasis (HAT) is a disease caused by infection with the parasite Trypanosoma brucei gambiense or T. b. rhodesiense. It is transmitted to humans via the tsetse fly. Approximately 70 million people worldwide were at risk of infection in 1995, and approximately 20,000 people across Africa are infected with HAT. The objective of this review was to identify existing economic evaluations in order to summarise cost-effective interventions to reduce, control, or eliminate the burden of HAT. The studies included in the review were compared and critically appraised in order to determine if there were existing standardised methods that could be used for economic evaluation of HAT interventions or if innovative methodological approaches are warranted. A search strategy was developed using keywords and was implemented in January 2014 in several databases. The search returned a total of 2,283 articles. After two levels of screening, a total of seven economic evaluations were included and underwent critical appraisal using the Scottish Intercollegiate Guidelines Network (SIGN) Methodology Checklist 6: Economic Evaluations. Results from the existing studies focused on the cost-effectiveness of interventions for the control and reduction of disease transmission. Modelling was a common method to forecast long-term results, and publications focused on interventions by category, such as case detection, diagnostics, drug treatments, and vector control. Most interventions were considered cost-effective based on the thresholds described; however, the current treatment, nifurtomix-eflornithine combination therapy (NECT), has not been evaluated for cost-effectiveness, and considerations for cost-effective strategies for elimination have yet to be completed. Overall, the current evidence highlights the main components that play a role in control; however, economic evaluations of HAT elimination strategies are needed to assist national decision makers, stakeholders, and key funders. These analyses would be of use, as HAT is currently being prioritized as a neglected tropical disease (NTD) to reach elimination by 2020.

A Strategy for Architecture Design of Crystalline Perovskite Light-Emitting Diodes with High Performance.

PubMed

Shi, Yifei; Wu, Wen; Dong, Hua; Li, Guangru; Xi, Kai; Divitini, Giorgio; Ran, Chenxin; Yuan, Fang; Zhang, Min; Jiao, Bo; Hou, Xun; Wu, Zhaoxin

2018-06-01

All present designs of perovskite light-emitting diodes (PeLEDs) stem from polymer light-emitting diodes (PLEDs) or perovskite solar cells. The optimal structure of PeLEDs can be predicted to differ from PLEDs due to the different fluorescence dynamics and crystallization between perovskite and polymer. Herein, a new design strategy and conception is introduced, "insulator-perovskite-insulator" (IPI) architecture tailored to PeLEDs. As examples of FAPbBr 3 and MAPbBr 3 , it is experimentally shown that the IPI structure effectively induces charge carriers into perovskite crystals, blocks leakage currents via pinholes in the perovskite film, and avoids exciton quenching simultaneously. Consequently, as for FAPbBr 3 , a 30-fold enhancement in the current efficiency of IPI-structured PeLEDs compared to a control device with poly(3,4ethylenedioxythiophene):poly(styrene sulfonate) as hole-injection layer is achieved-from 0.64 to 20.3 cd A -1 -while the external quantum efficiency is increased from 0.174% to 5.53%. As the example of CsPbBr 3 , compared with the control device, both current efficiency and lifetime of IPI-structured PeLEDs are improved from 1.42 and 4 h to 9.86 cd A -1 and 96 h. This IPI architecture represents a novel strategy for the design of light-emitting didoes based on various perovskites with high efficiencies and stabilities. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The use of cognitive task analysis to improve the learning of percutaneous tracheostomy placement.

PubMed

Sullivan, Maura E; Brown, Carlos V R; Peyre, Sarah E; Salim, Ali; Martin, Matthew; Towfigh, Shirin; Grunwald, Tiffany

2007-01-01

The purpose of the current study was to determine the effectiveness of using cognitive task analysis (CTA) to develop a curriculum to teach the behavioral skills and the cognitive strategies of a percutaneous tracheostomy (PT) placement. Postgraduate 2, 3, and 4 general surgery residents were randomly assigned to either the CTA group (N = 9) or the control group (N = 11). The CTA group was taught percutaneous tracheostomy placement using the CTA curriculum. The control group received the traditional curriculum. The CTA group performed significantly higher on the PT procedure at 1 month (CTA: 43.5 +/- 3.7, control 35.2 +/- 3.9, P = .001) and at 6 months post-instruction (CTA: 39.4 +/- 4.2, control: 31.8 +/- 5.8, P = .004). In addition, the CTA group demonstrated superior cognitive strategies than the control group (CTA: 25.4 +/- 5.3, control: 19.2 +/- 2.0, P = .004). The use of CTA was effective in improving the cognitive processes and technical skills of performing a PT for surgical residents.

Coordinated Control of Cross-Flow Turbines

NASA Astrophysics Data System (ADS)

Strom, Benjamin; Brunton, Steven; Polagye, Brian

2016-11-01

Cross-flow turbines, also known as vertical-axis turbines, have several advantages over axial-flow turbines for a number of applications including urban wind power, high-density arrays, and marine or fluvial currents. By controlling the angular velocity applied to the turbine as a function of angular blade position, we have demonstrated a 79 percent increase in cross-flow turbine efficiency over constant-velocity control. This strategy uses the downhill simplex method to optimize control parameter profiles during operation of a model turbine in a recirculating water flume. This optimization method is extended to a set of two turbines, where the blade motions and position of the downstream turbine are optimized to beneficially interact with the coherent structures in the wake of the upstream turbine. This control scheme has the potential to enable high-density arrays of cross-flow turbines to operate at cost-effective efficiency. Turbine wake and force measurements are analyzed for insight into the effect of a coordinated control strategy.

Cluster analysis of the national weight control registry to identify distinct subgroups maintaining successful weight loss.

PubMed

Ogden, Lorraine G; Stroebele, Nanette; Wyatt, Holly R; Catenacci, Victoria A; Peters, John C; Stuht, Jennifer; Wing, Rena R; Hill, James O

2012-10-01

The National Weight Control Registry (NWCR) is the largest ongoing study of individuals successful at maintaining weight loss; the registry enrolls individuals maintaining a weight loss of at least 13.6 kg (30 lb) for a minimum of 1 year. The current report uses multivariate latent class cluster analysis to identify unique clusters of individuals within the NWCR that have distinct experiences, strategies, and attitudes with respect to weight loss and weight loss maintenance. The cluster analysis considers weight and health history, weight control behaviors and strategies, effort and satisfaction with maintaining weight, and psychological and demographic characteristics. The analysis includes 2,228 participants enrolled between 1998 and 2002. Cluster 1 (50.5%) represents a weight-stable, healthy, exercise conscious group who are very satisfied with their current weight. Cluster 2 (26.9%) has continuously struggled with weight since childhood; they rely on the greatest number of resources and strategies to lose and maintain weight, and report higher levels of stress and depression. Cluster 3 (12.7%) represents a group successful at weight reduction on the first attempt; they were least likely to be overweight as children, are maintaining the longest duration of weight loss, and report the least difficulty maintaining weight. Cluster 4 (9.9%) represents a group less likely to use exercise to control weight; they tend to be older, eat fewer meals, and report more health problems. Further exploration of the unique characteristics of these clusters could be useful for tailoring future weight loss and weight maintenance programs to the specific characteristics of an individual.

Propaganda and pretext.

PubMed

Holt, Sidney

2006-04-01

This Viewpoint describes and analyses the history and current features of the strategy of the Government of Japan, and the associated Institute for Cetacean Research in Tokyo, to regain control of the International Whaling Commission (IWC), to legitimise renewed unsustainable commercial whaling and to dismantle conservation measures taken by the IWC over the past three decades. A key element in that strategy now is to promote and nourish the false idea that the present crisis in world fisheries is significantly caused by the consumption of valuable fish by increasing whale populations.

Terminal Area Productivity Program: Dynamic Spacing Human Factors

NASA Technical Reports Server (NTRS)

Kanki, Barbara G.

1997-01-01

Dynamic spacing human factors deals with the following human factors issues: define controller limits to incorporating dynamic changes in separation standards; identify timing, planning, and coordination strategies; and consider consistency with current practices, policies, and regulations. The AVOSS technologies will make it possible to reduce separation standards in the terminal area under certain meteorological conditions. This paper contains the following sections: Dynamic space human factors overview, Preliminary tests, and current research status & plans.

Simulation in Training--The Current Imperative.

DTIC Science & Technology

1980-05-16

Carlisle Barracks, PA 17013 - I1. CONTROLLING OFFICE NAME AND ADDRESS 12 . REPORT DATE I. NUMBER OF PAGES 24 14. MONITORING AGENCY NAME & ADDRESSQIf different...growth in components, spare parts, fuel and lubricants, as well as limited space in which to train, the Army must adapt a strategy of field train- ing...I________________________ k AUTHOR(S): Richard P. Diehl, LTC, INF TITLE: Simulation in Training--The Current Imperative FORMAT: Individual Study Project DATE: 16

A model predictive current control of flux-switching permanent magnet machines for torque ripple minimization

NASA Astrophysics Data System (ADS)

Huang, Wentao; Hua, Wei; Yu, Feng

2017-05-01

Due to high airgap flux density generated by magnets and the special double salient structure, the cogging torque of the flux-switching permanent magnet (FSPM) machine is considerable, which limits the further applications. Based on the model predictive current control (MPCC) and the compensation control theory, a compensating-current MPCC (CC-MPCC) scheme is proposed and implemented to counteract the dominated components in cogging torque of an existing three-phase 12/10 FSPM prototyped machine, and thus to alleviate the influence of the cogging torque and improve the smoothness of electromagnetic torque as well as speed, where a comprehensive cost function is designed to evaluate the switching states. The simulated results indicate that the proposed CC-MPCC scheme can suppress the torque ripple significantly and offer satisfactory dynamic performances by comparisons with the conventional MPCC strategy. Finally, experimental results validate both the theoretical and simulated predictions.

Tools and Strategies for Malaria Control and Elimination: What Do We Need to Achieve a Grand Convergence in Malaria?

PubMed Central

Hemingway, Janet; Shretta, Rima; Wells, Timothy N. C.; Bell, David; Djimdé, Abdoulaye A.; Achee, Nicole; Qi, Gao

2016-01-01

Progress made in malaria control during the past decade has prompted increasing global dialogue on malaria elimination and eradication. The product development pipeline for malaria has never been stronger, with promising new tools to detect, treat, and prevent malaria, including innovative diagnostics, medicines, vaccines, vector control products, and improved mechanisms for surveillance and response. There are at least 25 projects in the global malaria vaccine pipeline, as well as 47 medicines and 13 vector control products. In addition, there are several next-generation diagnostic tools and reference methods currently in development, with many expected to be introduced in the next decade. The development and adoption of these tools, bolstered by strategies that ensure rapid uptake in target populations, intensified mechanisms for information management, surveillance, and response, and continued financial and political commitment are all essential to achieving global eradication. PMID:26934361

Tools and Strategies for Malaria Control and Elimination: What Do We Need to Achieve a Grand Convergence in Malaria?

PubMed

Hemingway, Janet; Shretta, Rima; Wells, Timothy N C; Bell, David; Djimdé, Abdoulaye A; Achee, Nicole; Qi, Gao

2016-03-01

Progress made in malaria control during the past decade has prompted increasing global dialogue on malaria elimination and eradication. The product development pipeline for malaria has never been stronger, with promising new tools to detect, treat, and prevent malaria, including innovative diagnostics, medicines, vaccines, vector control products, and improved mechanisms for surveillance and response. There are at least 25 projects in the global malaria vaccine pipeline, as well as 47 medicines and 13 vector control products. In addition, there are several next-generation diagnostic tools and reference methods currently in development, with many expected to be introduced in the next decade. The development and adoption of these tools, bolstered by strategies that ensure rapid uptake in target populations, intensified mechanisms for information management, surveillance, and response, and continued financial and political commitment are all essential to achieving global eradication.

Multidrug-resistant opportunistic pathogens challenging veterinary infection control.

PubMed

Walther, Birgit; Tedin, Karsten; Lübke-Becker, Antina

2017-02-01

Although the problems associated with healthcare-associated infections (HAI) and the emergence of zoonotic and multidrug-resistant pathogens in companion animal (dogs, cats and horses) medicine have been well-known for decades, current progress with respect to practical implementation of infection control programs in veterinary clinics has been limited. Clinical outbreak events reported for methicillin-resistant Staphylooccus aureus (MRSA) and Staphylococcus pseudintermedius (MRSP), extended spectrum beta-lactamase (ESBL)-producing Escherichia coli and multidrug-resistant (MDR) Salmonella Serovars indicate the necessity of infection control strategies for protecting animal patients at risk as well as veterinary personnel. The close bond between humans and their companion animals provides opportunities for exchange of microorganisms, including MDR pathogens. This particular aspect of the "One Health" idea requires more representative surveillance efforts and infection control strategies with respect to animal-species specific characters. Copyright © 2016 Elsevier B.V. All rights reserved.

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

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.

Developments in a centrifugal compressor surge control -- a technology assessment

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

Botros, K.K.; Henderson, J.F.

1994-04-01

There are a number of surge control schemes in current use for centrifugal compressors employed in natural gas transmission systems. Basically, these schemes consist of a set of detection devices that either anticipate surge or detect it at its inception, and a set of control devices that act to prevent surge from occurring. A patent search was conducted in an attempt to assess the level and direction of technology development over the last 20 years and to define the focus for future R D activities. In addition, the paper presents the current state of technology in three areas: surge control,more » surge detection, and surge suppression. Patent data obtained from on-line databases showed that most of the emphasis has been on surge control rather than on detection and control and that the current trend in surge control will likely continue toward incremental improvement of a basic or conventional surge control strategy. Various surge suppression techniques can be grouped in two categories: (1) those that are focused on better compressor interior design, and (2) others that attempt to suppress surge by external and operational means.« less

Single-stage three-phase boost power factor correction circuit for AC-DC converter

NASA Astrophysics Data System (ADS)

Azazi, Haitham Z.; Ahmed, Sayed M.; Lashine, Azza E.

2018-01-01

This article presents a single-stage three-phase power factor correction (PFC) circuit for AC-to-DC converter using a single-switch boost regulator, leading to improve the input power factor (PF), reducing the input current harmonics and decreasing the number of required active switches. A novel PFC control strategy which is characterised as a simple and low-cost control circuit was adopted, for achieving a good dynamic performance, unity input PF, and minimising the harmonic contents of the input current, at which it can be applied to low/medium power converters. A detailed analytical, simulation and experimental studies were therefore conducted. The effectiveness of the proposed controller algorithm is validated by the simulation results, which were carried out using MATLAB/SIMULINK environment. The proposed system is built and tested in the laboratory using DSP-DS1104 digital control board for an inductive load. The results revealed that the total harmonic distortion in the supply current was very low. Finally, a good agreement between simulation and experimental results was achieved.

Intercepting a moving target: On-line or model-based control?

PubMed

Zhao, Huaiyong; Warren, William H

2017-05-01

When walking to intercept a moving target, people take an interception path that appears to anticipate the target's trajectory. According to the constant bearing strategy, the observer holds the bearing direction of the target constant based on current visual information, consistent with on-line control. Alternatively, the interception path might be based on an internal model of the target's motion, known as model-based control. To investigate these two accounts, participants walked to intercept a moving target in a virtual environment. We degraded the target's visibility by blurring the target to varying degrees in the midst of a trial, in order to influence its perceived speed and position. Reduced levels of visibility progressively impaired interception accuracy and precision; total occlusion impaired performance most and yielded nonadaptive heading adjustments. Thus, performance strongly depended on current visual information and deteriorated qualitatively when it was withdrawn. The results imply that locomotor interception is normally guided by current information rather than an internal model of target motion, consistent with on-line control.

Recurrent urinary tract infections in women.

PubMed

Aydin, Abdullatif; Ahmed, Kamran; Zaman, Iftikhar; Khan, Muhammad Shamim; Dasgupta, Prokar

2015-06-01

Recurrent urinary tract infections (UTIs) are more common in women and are frequently defined as ≥2 episodes in the last 6 months or ≥3 episodes in the last 12 months. In a primary care setting, 53 % of women above the age of 55 years and 36 % of younger women report a recurrence within 1 year. Thus, management and prevention of recurrent UTI is of utmost significance. This review aims to highlight the latest research in prevention strategies and suggest a management pathway. A search was conducted on MEDLINE, Embase and the Cochrane Database of Systematic Reviews databases for the latest systematic reviews and high-quality randomized controlled trials. Special emphasis was placed on the remit "recurrent" and strongly adhered to. Furthermore, a Google search was conducted for current guidelines on the management of UTIs. Current prevention strategies include eliminating risk factors that increase the risk of acquiring recurrent UTI and continuous, post-coital and self-initiated antimicrobial prophylaxis. Other prospective preventative strategies, currently under trial, include use of vaccinations, D-mannose and lactobacillus (probiotics). Although risk factors should be identified and addressed accordingly, individualized antibiotic prophylaxis remains the most effective method of management. Non-antibiotic prevention strategies such as cranberry, vitamin C and methenamine salts lack strong evidence to be introduced as routine management options and as alternatives to antibiotics. Based on current evidence and guidelines, a management pathway is recommended. Emerging therapies require further evaluation before they can be recommended.

Cognitive Rehabilitation: ACTION Training for Soldiers with Executive Dysfunction

DTIC Science & Technology

2015-10-01

failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO... controlled trial. Aim 1: Finalize ACTION curriculum/ manuals; field test Aim 2: Evaluate ACTION instructional methods (the extent to which SM with...metacognitive strategy instruction (MSI), together called Target Acquisition Practices ( Group 1) by evaluating the extent to which training 1) improves

Epidemiological models to control the spread of information in marine mammals.

PubMed

Schakner, Zachary A; Buhnerkempe, Michael G; Tennis, Mathew J; Stansell, Robert J; van der Leeuw, Bjorn K; Lloyd-Smith, James O; Blumstein, Daniel T

2016-12-14

Socially transmitted wildlife behaviours that create human-wildlife conflict are an emerging problem for conservation efforts, but also provide a unique opportunity to apply principles of infectious disease control to wildlife management. As an example, California sea lions (Zalophus californianus) have learned to exploit concentrations of migratory adult salmonids below the fish ladders at Bonneville Dam, impeding endangered salmonid recovery. Proliferation of this foraging behaviour in the sea lion population has resulted in a controversial culling programme of individual sea lions at the dam, but the impact of such culling remains unclear. To evaluate the effectiveness of current and alternative culling strategies, we used network-based diffusion analysis on a long-term dataset to demonstrate that social transmission is implicated in the increase in dam-foraging behaviour and then studied different culling strategies within an epidemiological model of the behavioural transmission data. We show that current levels of lethal control have substantially reduced the rate of social transmission, but failed to effectively reduce overall sea lion recruitment. Earlier implementation of culling could have substantially reduced the extent of behavioural transmission and, ultimately, resulted in fewer animals being culled. Epidemiological analyses offer a promising tool to understand and control socially transmissible behaviours. © 2016 The Author(s).

Fish Vaccines: Current State and Future Trends

USDA-ARS?s Scientific Manuscript database

A vaccine is a preventive tool used in a health management strategy for the control of infectious diseases. For more than 100 years, vaccines have proved to be effective for preventing infectious disease outbreaks in humans, poultry and other food animals. In aquaculture, the development and use of...

Controlling Johne's disease: Vaccination is the way forward

USDA-ARS?s Scientific Manuscript database

In this article, we summarize current research on the state of vaccination against Johne’s disease. We promote the use of live attenuated vaccine candidates over subunit approaches, but don’t wholly discount other strategies. We conclude by suggesting new research directions that may make the highes...

Rational design of gene-based vaccines.

PubMed

Barouch, Dan H

2006-01-01

Vaccine development has traditionally been an empirical discipline. Classical vaccine strategies include the development of attenuated organisms, whole killed organisms, and protein subunits, followed by empirical optimization and iterative improvements. While these strategies have been remarkably successful for a wide variety of viruses and bacteria, these approaches have proven more limited for pathogens that require cellular immune responses for their control. In this review, current strategies to develop and optimize gene-based vaccines are described, with an emphasis on novel approaches to improve plasmid DNA vaccines and recombinant adenovirus vector-based vaccines. Copyright 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Study of Measurement Strategies of Geometric Deviation of the Position of the Threaded Holes

NASA Astrophysics Data System (ADS)

Drbul, Mário; Martikan, Pavol; Sajgalik, Michal; Czan, Andrej; Broncek, Jozef; Babik, Ondrej

2017-12-01

Verification of product and quality control is an integral part of current production process. In terms of functional requirements and product interoperability, it is necessary to analyze their dimensional and also geometric specifications. Threaded holes are verified elements too, which are a substantial part of detachable screw connections and have a broad presence in engineering products. This paper deals with on the analysing of measurement strategies of verification geometric deviation of the position of the threaded holes, which are the indirect method of measuring threaded pins when applying different measurement strategies which can affect the result of the verification of the product..

Strategies for prevention of road traffic injuries (RTIs) in Pakistan: situational analysis.

PubMed

Khan, Adeel Ahmed; Fatmi, Zafar

2014-05-01

Road traffic injuries (RTIs) are one of the leading causes of death among productive age group. Using systems approach framework (SAF), current preventive strategies for RTI control were reviewed in Pakistan. A review of the literature was done using four international search engines. Only ten studies on preventive strategies for RTI stemming from Pakistan were found. The first Road Traffic Injuries Research Network (RTIRN) surveillance system for road traffic injuries was established in urban city (Karachi) in Pakistan has shown promise for injury control and should be scaled up to other cities. Enforcement of traffic laws on seat-belt and helmet wearing is poor. National Highway and Motorway Police Ordinance (2000) was one of the few legislative measure so far taken in Pakistan. Using SAF, efforts are required to implement interventions targeting human, vehicle design and also making environment safer for road users.

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

PubMed

Yen, Gary G; Ho, Liang-Wei

2004-10-01

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

[SWOT Analysis of the National Survey on Current Status of Major Human Parasitic Diseases in China].

PubMed

ZHU, Hui-hui; ZHOU, Chang-hai; CHEN, Ying-dan; ZANG, Wei; XIAO, Ning; ZHOU, Xiao-nong

2015-10-01

The National Survey on Current Status of Major Human Parasitic Diseases in China has been carried out since 2014 under the organization of the National Health and Family Planning Commission of the People's Republic of China. The National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (NIPD, China CDC) provided technical support and was responsible for quality control in this survey. This study used SWOT method to analyze the strengths, weaknesses, opportunities and threats that were encountered by he NIPD, China CDC during the completion of the survey. Accordingly, working strategies were proposed to facilitate the future field work.

Air traffic control resource management strategies and the small aircraft transportation system: A system dynamics perspective

NASA Astrophysics Data System (ADS)

Galvin, James J., Jr.

The National Aeronautics and Space Administration (NASA) is leading a research effort to develop a Small Aircraft Transportation System (SATS) that will expand air transportation capabilities to hundreds of underutilized airports in the United States. Most of the research effort addresses the technological development of the small aircraft as well as the systems to manage airspace usage and surface activities at airports. The Federal Aviation Administration (FAA) will also play a major role in the successful implementation of SATS, however, the administration is reluctant to embrace the unproven concept. The purpose of the research presented in this dissertation is to determine if the FAA can pursue a resource management strategy that will support the current radar-based Air Traffic Control (ATC) system as well as a Global Positioning Satellite (GPS)-based ATC system required by the SATS. The research centered around the use of the System Dynamics modeling methodology to determine the future behavior of the principle components of the ATC system over time. The research included a model of the ATC system consisting of people, facilities, equipment, airports, aircraft, the FAA budget, and the Airport and Airways Trust Fund. The model generated system performance behavior used to evaluate three scenarios. The first scenario depicted the base case behavior of the system if the FAA continued its current resource management practices. The second scenario depicted the behavior of the system if the FAA emphasized development of GPS-based ATC systems. The third scenario depicted a combined resource management strategy that supplemented radar systems with GPS systems. The findings of the research were that the FAA must pursue a resource management strategy that primarily funds a radar-based ATC system and directs lesser funding toward a GPS-based supplemental ATC system. The most significant contribution of this research was the insight and understanding gained of how several resource management strategies and the presence of SATS aircraft may impact the future US Air Traffic Control system.

Fires in refugee and displaced persons settlements: the current situation and opportunities to improve fire prevention and control

PubMed Central

Kazerooni, Yasaman; Gyedu, Adam; Burnham, Gilbert; Nwomeh, Benedict; Charles, Anthony; Mishra, Brijesh; Kuah, Solomon S; Kushner, Adam L; Stewart, Barclay T

2015-01-01

Introduction We aimed to describe the burden of fires in displaced persons settlements and identify interventions/innovations that might address gaps in current humanitarian guidelines. Methods We performed a systematic review of: i) academic and non-academic literature databases; and ii) guidelines from leading humanitarian agencies/initiatives regarding fire prevention/control. Results Of the 1,521 records retrieved, 131 reports described settlement fires in 31 hosting countries since 1990. These incidents resulted in 487 deaths, 790 burn injuries, displacement of 382,486 individuals and destruction of 50,509 shelters. There was a 25-fold increase in the rate of settlement fires from 1990 to 2015 (0.002 to 0.051 per 100,000 refugees, respectively). Only 4 of the 15 leading humanitarian agencies provided recommendations about fire prevention/control strategies. Potentially useful interventions/innovations included safer stoves (e.g. solar cookers) and fire retardant shelter materials. Conclusion The large and increasing number of fires in displaced persons settlements highlights the need to redress gaps in humanitarian fire prevention/control guidelines. The way forward includes: i) developing consensus among aid agencies regarding fire prevention/control strategies; ii) evaluating the impact of interventions/innovations on the burden of fires; and iii) engaging agencies in a broader discussion about protecting camp residents from armed groups. PMID:26818955

Fires in refugee and displaced persons settlements: The current situation and opportunities to improve fire prevention and control.

PubMed

Kazerooni, Yasaman; Gyedu, Adam; Burnham, Gilbert; Nwomeh, Benedict; Charles, Anthony; Mishra, Brijesh; Kuah, Solomon S; Kushner, Adam L; Stewart, Barclay T

2016-08-01

We aimed to describe the burden of fires in displaced persons settlements and identify interventions/innovations that might address gaps in current humanitarian guidelines. We performed a systematic review of: (i) academic and non-academic literature databases; and (ii) guidelines from leading humanitarian agencies/initiatives regarding fire prevention/control. Of the 1521 records retrieved, 131 reports described settlement fires in 31 hosting countries since 1990. These incidents resulted in 487 deaths, 790 burn injuries, displacement of 382,486 individuals and destruction of 50,509 shelters. There was a 25-fold increase in the rate of settlement fires from 1990 to 2015 (0.002-0.051 per 100,000 refugees, respectively). Only 4 of the 15 leading humanitarian agencies provided recommendations about fire prevention/control strategies. Potentially useful interventions/innovations included safer stoves (e.g. solar cookers) and fire retardant shelter materials. The large and increasing number of fires in displaced persons settlements highlights the need to redress gaps in humanitarian fire prevention/control guidelines. The way forward includes: (i) developing consensus among aid agencies regarding fire prevention/control strategies; (ii) evaluating the impact of interventions/innovations on the burden of fires; and (iii) engaging agencies in a broader discussion about protecting camp residents from armed groups. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

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

Lykkebo, Jacob; Solomon, Gemma C., E-mail: gsolomon@nano.ku.dk; Romano, Giuseppe

Electronic devices composed of single molecules constitute the ultimate limit in the continued downscaling of electronic components. A key challenge for single-molecule electronics is to control the temperature of these junctions. Controlling heating and cooling effects in individual vibrational modes can, in principle, be utilized to increase stability of single-molecule junctions under bias, to pump energy into particular vibrational modes to perform current-induced reactions, or to increase the resolution in inelastic electron tunneling spectroscopy by controlling the life-times of phonons in a molecule by suppressing absorption and external dissipation processes. Under bias the current and the molecule exchange energy, whichmore » typically results in heating of the molecule. However, the opposite process is also possible, where energy is extracted from the molecule by the tunneling current. Designing a molecular “heat sink” where a particular vibrational mode funnels heat out of the molecule and into the leads would be very desirable. It is even possible to imagine how the vibrational energy of the other vibrational modes could be funneled into the “cooling mode,” given the right molecular design. Previous efforts to understand heating and cooling mechanisms in single molecule junctions have primarily been concerned with small models, where it is unclear which molecular systems they correspond to. In this paper, our focus is on suppressing heating and obtaining current-induced cooling in certain vibrational modes. Strategies for cooling vibrational modes in single-molecule junctions are presented, together with atomistic calculations based on those strategies. Cooling and reduced heating are observed for two different cooling schemes in calculations of atomistic single-molecule junctions.« less

VOC from Vehicular Evaporation Emissions: Status and Control Strategy.

PubMed

Liu, Huan; Man, Hanyang; Tschantz, Michael; Wu, Ye; He, Kebin; Hao, Jiming

2015-12-15

Vehicular evaporative emissions is an important source of volatile organic carbon (VOC), however, accurate estimation of emission amounts and scientific evaluation of control strategy for these emissions have been neglected outside of the United States. This study provides four kinds of basic emission factors: diurnal, hot soak, permeation, and refueling. Evaporative emissions from the Euro 4 vehicles (1.6 kg/year/car) are about four times those of U.S. vehicles (0.4 kg/year/car). Closing this emissions gap would have a larger impact than the progression from Euro 3 to Euro 6 tailpipe HC emission controls. Even in the first 24 h of parking, China's current reliance upon the European 24 h diurnal standard results in 508 g/vehicle/year emissions, higher than 32 g/vehicle/year from Tier 2 vehicles. The U.S. driving cycle matches Beijing real-world conditions much better on both typical trip length and average speed than current European driving cycles. At least two requirements should be added to the Chinese emissions standards: an onboard refueling vapor recovery to force the canister to be sized sufficiently large, and a 48-h evaporation test requirement to ensure that adequate purging occurs over a shorter drive sequence.

The 'Toolbox' of strategies for managing Haemonchus contortus in goats: What's in and what's out.

PubMed

Kearney, P E; Murray, P J; Hoy, J M; Hohenhaus, M; Kotze, A

2016-04-15

A dynamic and innovative approach to managing the blood-consuming nematode Haemonchus contortus in goats is critical to crack dependence on veterinary anthelmintics. H. contortus management strategies have been the subject of intense research for decades, and must be selected to create a tailored, individualized program for goat farms. Through the selection and combination of strategies from the Toolbox, an effective management program for H. contortus can be designed according to the unique conditions of each particular farm. This Toolbox investigates strategies including vaccines, bioactive forages, pasture/grazing management, behavioural management, natural immunity, FAMACHA, Refugia and strategic drenching, mineral/vitamin supplementation, copper Oxide Wire Particles (COWPs), breeding and selection/selecting resistant and resilient individuals, biological control and anthelmintic drugs. Barbervax(®), the ground-breaking Haemonchus vaccine developed and currently commercially available on a pilot scale for sheep, is prime for trialling in goats and would be an invaluable inclusion to this Toolbox. The specialised behaviours of goats, specifically their preferences to browse a variety of plants and accompanying physiological adaptations to the consumption of secondary compounds contained in browse, have long been unappreciated and thus overlooked as a valuable, sustainable strategy for Haemonchus management. These strategies are discussed in this review as to their value for inclusion into the 'Toolbox' currently, and the future implications of ongoing research for goat producers. Combining and manipulating strategies such as browsing behaviour, pasture management, bioactive forages and identifying and treating individual animals for haemonchosis, in addition to continuous evaluation of strategy effectiveness, is conducted using a model farm scenario. Selecting strategies from the Toolbox, with regard to their current availability, feasibility, economical cost and potential ease of implementation depending on the systems of production and their complementary nature, is the future of managing H. contortus in farmed goats internationally and maintaining the remaining efficacy of veterinary anthelmintics. Copyright © 2016 Elsevier B.V. All rights reserved.

Efficacy of commercial vaccines against newly emerging avian influenza H5N8 virus in Egypt.

PubMed

Kandeil, Ahmed; Sabir, Jamal S M; Abdelaal, Ahmed; Mattar, Ehab H; El-Taweel, Ahmed N; Sabir, Mumdooh J; Khalil, Ahmed Aly; Webby, Richard; Kayali, Ghazi; Ali, Mohamed A

2018-06-26

The newly emerging, highly pathogenic avian influenza (HPAI) H5N8 virus of clade 2.3.4.4 was recently detected in wild birds and domestic poultry in Egypt in the 2016/2017 winter season. Vaccination based on commercial H5 vaccines is used as an essential control strategy in Egyptian poultry. Here, we studied the efficacy of the eight most common commercial H5 poultry vaccines in the Egyptian market and compared them with an experimental vaccine based on the Egyptian LPAI H5N8 virus that was prepared by using reverse genetics. The experimental vaccine and Re-5 commercial vaccine were able to completely protect chickens and significantly reduce virus shedding. Our results indicate that most of the commercial poultry H5 vaccines used in the present study were ineffective because the seed viruses in these vaccines are genetically distinct from the H5N8 viruses currently circulating in Egypt. Although some of the commercial vaccines protected chickens from mortality, they failed to prevent chickens from shedding the virus. Accordingly, we recommend updating and reinforcing the H5N8 prevention and control strategies in Egypt. The vaccination strategy should be reconsidered based on currently circulating viruses.

Tissue Engineering at the Blood-Contacting Surface: A Review of Challenges and Strategies in Vascular Graft Development.

PubMed

Radke, Daniel; Jia, Wenkai; Sharma, Dhavan; Fena, Kemin; Wang, Guifang; Goldman, Jeremy; Zhao, Feng

2018-05-07

Tissue engineered vascular grafts (TEVGs) are beginning to achieve clinical success and hold promise as a source of grafting material when donor grafts are unsuitable or unavailable. Significant technological advances have generated small-diameter TEVGs that are mechanically stable and promote functional remodeling by regenerating host cells. However, developing a biocompatible blood-contacting surface remains a major challenge. The TEVG luminal surface must avoid negative inflammatory responses and thrombogenesis immediately upon implantation and promote endothelialization. The surface has therefore become a primary focus for research and development efforts. The current state of TEVGs is herein reviewed with an emphasis on the blood-contacting surface. General vascular physiology and developmental challenges and strategies are briefly described, followed by an overview of the materials currently employed in TEVGs. The use of biodegradable materials and stem cells requires careful control of graft composition, degradation behavior, and cell recruitment ability to ensure that a physiologically relevant vessel structure is ultimately achieved. The establishment of a stable monolayer of endothelial cells and the quiescence of smooth muscle cells are critical to the maintenance of patency. Several strategies to modify blood-contacting surfaces to resist thrombosis and control cellular recruitment are reviewed, including coatings of biomimetic peptides and heparin. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Broomrape Weeds. Underground Mechanisms of Parasitism and Associated Strategies for their Control: A Review

PubMed Central

Fernández-Aparicio, Mónica; Reboud, Xavier; Gibot-Leclerc, Stephanie

2016-01-01

Broomrapes are plant-parasitic weeds which constitute one of the most difficult-to-control of all biotic constraints that affect crops in Mediterranean, central and eastern Europe, and Asia. Due to their physical and metabolic overlap with the crop, their underground parasitism, their achlorophyllous nature, and hardly destructible seed bank, broomrape weeds are usually not controlled by management strategies designed for non-parasitic weeds. Instead, broomrapes are in current state of intensification and spread due to lack of broomrape-specific control programs, unconscious introduction to new areas and may be decline of herbicide use and global warming to a lesser degree. We reviewed relevant facts about the biology and physiology of broomrape weeds and the major feasible control strategies. The points of vulnerability of some underground events, key for their parasitism such as crop-induced germination or haustorial development are reviewed as inhibition targets of the broomrape-crop association. Among the reviewed strategies are those aimed (1) to reduce broomrape seed bank viability, such as fumigation, herbigation, solarization and use of broomrape-specific pathogens; (2) diversion strategies to reduce the broomrape ability to timely detect the host such as those based on promotion of suicidal germination, on introduction of allelochemical interference, or on down-regulating host exudation of germination-inducing factors; (3) strategies to inhibit the capacity of the broomrape seedling to penetrate the crop and connect with the vascular system, such as biotic or abiotic inhibition of broomrape radicle growth and crop resistance to broomrape penetration either natural, genetically engineered or elicited by biotic- or abiotic-resistance-inducing agents; and (4) strategies acting once broomrape seedling has bridged its vascular system with that of the host, aimed to impede or to endure the parasitic sink such as those based on the delivery of herbicides via haustoria, use of resistant or tolerant varieties and implementation of cultural practices improving crop competitiveness. PMID:26925071

Effects of different lower-limb sensory stimulation strategies on postural regulation—A systematic review and meta-analysis

PubMed Central

Davids, Keith; Liukkonen, Jarmo; Orth, Dominic; Chow, Jia Yi; Jaakkola, Timo

2017-01-01

Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high- pooled effect sizes (Unbiased (Hedges’ g) standardized mean differences (SMD) = 0.31–0.66) were observed with the addition of noise in a Stochastic Resonance Stimulation Strategy (SRSS), in three populations (i.e., healthy young adults, older adults, and individuals with lower-limb injuries), and under different task constraints (i.e., unipedal, bipedal, and eyes open). A Textured Material Stimulation Strategy (TMSS) enhanced postural control in the most challenging condition—eyes-closed on a stable surface (SMD = 0.61), and in older adults (SMD = 0.30). The Wearable Garments Stimulation Strategy (WGSS) showed no or adverse effects (SMD = -0.68–0.05) under all task constraints and in all populations, except in individuals with lower-limb injuries (SMD = 0.20). Results of our systematic review and meta-analysis revealed that future research could consider combining two or more stimulation strategies in intervention treatments for postural regulation and balance problems, depending on individual needs. PMID:28355265

Design of a minimally constraining, passively supported gait training exoskeleton: ALEX II.

PubMed

Winfree, Kyle N; Stegall, Paul; Agrawal, Sunil K

2011-01-01

This paper discusses the design of a new, minimally constraining, passively supported gait training exoskeleton known as ALEX II. This device builds on the success and extends the features of the ALEX I device developed at the University of Delaware. Both ALEX (Active Leg EXoskeleton) devices have been designed to supply a controllable torque to a subject's hip and knee joint. The current control strategy makes use of an assist-as-needed algorithm. Following a brief review of previous work motivating this redesign, we discuss the key mechanical features of the new ALEX device. A short investigation was conducted to evaluate the effectiveness of the control strategy and impact of the exoskeleton on the gait of six healthy subjects. This paper concludes with a comparison between the subjects' gait both in and out of the exoskeleton. © 2011 IEEE

A Taxonomy of Attacks on the DNP3 Protocol

NASA Astrophysics Data System (ADS)

East, Samuel; Butts, Jonathan; Papa, Mauricio; Shenoi, Sujeet

Distributed Network Protocol (DNP3) is the predominant SCADA protocol in the energy sector - more than 75% of North American electric utilities currently use DNP3 for industrial control applications. This paper presents a taxonomy of attacks on the protocol. The attacks are classified based on targets (control center, outstation devices and network/communication paths) and threat categories (interception, interruption, modification and fabrication). To facilitate risk analysis and mitigation strategies, the attacks are associated with the specific DNP3 protocol layers they exploit. Also, the operational impact of the attacks is categorized in terms of three key SCADA objectives: process confi- dentiality, process awareness and process control. The attack taxonomy clarifies the nature and scope of the threats to DNP3 systems, and can provide insights into the relative costs and benefits of implementing mitigation strategies.

Anti-arrhythmic strategies for atrial fibrillation

PubMed Central

Grandi, Eleonora; Maleckar, Mary M.

2016-01-01

Atrial fibrillation (AF), the most common cardiac arrhythmia, is associated with increased risk of cerebrovascular stroke, and with several other pathologies, including heart failure. Current therapies for AF are targeted at reducing risk of stroke (anticoagulation) and tachycardia-induced cardiomyopathy (rate or rhythm control). Rate control, typically achieved by atrioventricular nodal blocking drugs, is often insufficient to alleviate symptoms. Rhythm control approaches include antiarrhythmic drugs, electrical cardioversion, and ablation strategies. Here, we offer several examples of how computational modeling can provide a quantitative framework for integrating multi scale data to: (a) gain insight into multi-scale mechanisms of AF; (b) identify and test pharmacological and electrical therapy and interventions; and (c) support clinical decisions. We review how modeling approaches have evolved and contributed to the research pipeline and preclinical development and discuss future directions and challenges in the field. PMID:27612549

Defrost Temperature Termination in Supermarket Refrigeration Systems

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

Fricke, Brian A; Sharma, Vishaldeep

2011-11-01

The objective of this project was to determine the potential energy savings associated with implementing demand defrost strategies to defrost supermarket refrigerated display case evaporators, as compared to the widely accepted current practice of controlling display case defrost cycles with a preset timer. The defrost heater energy use of several representative display case types was evaluated. In addition, demand defrost strategies for refrigerated display cases as well as those used in residential refrigerator/freezers were evaluated. Furthermore, it is anticipated that future work will include identifying a preferred defrost strategy, with input from Retail Energy Alliance members. Based on this strategy,more » a demand defrost system will be designed which is suitable for supermarket refrigerated display cases. Limited field testing of the preferred defrost strategy will be performed in a supermarket environment.« less

Single-leg drop landing motor control strategies following acute ankle sprain injury.

PubMed

Doherty, C; Bleakley, C; Hertel, J; Caulfield, B; Ryan, J; Delahunt, E

2015-08-01

No research currently exists investigating the effect of acute injury on single-limb landing strategies. The aim of the current study was to analyze the coordination strategies of participants in the acute phase of lateral ankle sprain (LAS) injury. Thirty-seven participants with acute, first-time LAS and 19 uninjured participants completed a single-leg drop landing task on both limbs. Three-dimensional kinematic (angular displacement) and sagittal plane kinetic (moment-of-force) data were acquired for the joints of the lower extremity from 200 ms pre-initial contact (IC) to 200 ms post-IC. The peak magnitude of the vertical component of the ground reaction force (GRF) was also computed. Injured participants displayed a bilateral increase in hip flexion, with altered transverse plane kinematic profiles at the knee and ankle for both limbs (P < 0.05). This coincided with a reduction in the net-supporting flexor moment of the lower extremity (P < 0.05) and magnitude of the peak vertical GRF for the injured limb (21.82 ± 2.44 N/kg vs 24.09 ± 2.77 N/kg; P = 0.013) in injured participants compared to control participants. These results demonstrate that compensatory movement strategies are utilized by participants with acute LAS to successfully reduce the impact forces of landing. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Inhibition of porcine reproductive and respiratory syndrome virus in vitro by forsythoside A

USDA-ARS?s Scientific Manuscript database

Porcine reproductive and respiratory syndrome virus (PRRSV) represents a significant challenge to the swine industry worldwide. Current control strategies against PRRSV are still inadequate and there is a need for new antiviral therapy method. Forsythoside is a compound derived from fruit of Forsy...

Biochar amendment to the soil surface reduces fumigant emissions and enhances soil microorganism recovery

USDA-ARS?s Scientific Manuscript database

During soil fumigation, it is ideal to mitigate soil fumigant emissions, ensure pest control efficacy, and speed up the recovery of the soil microorganism population established post-application. However, there is currently no fumigant emission reduction strategy that can meet all the above requirem...

Weed biocontrol in the EU: from serendipity to strategy

USDA-ARS?s Scientific Manuscript database

Biological control of weeds is a globally-recognized approach to the management of the worst invasive plants in the world. Unfortunately, accidental introduction of agents account for most weed biocontrol in the EU, but do include a number of current or emerging successes. From the redistribution of...

Automating the conflict resolution process

NASA Technical Reports Server (NTRS)

Wike, Jeffrey S.

1991-01-01

The purpose is to initiate a discussion of how the conflict resolution process at the Network Control Center can be made more efficient. Described here are how resource conflicts are currently resolved as well as the impacts of automating conflict resolution in the ATDRSS era. A variety of conflict resolution strategies are presented.

Timing and Methodology of Application of Azoxystrobin to Control Rhizoctonia Solani in Sugarbeet

USDA-ARS?s Scientific Manuscript database

Rhizoctonia solani AG 2-2 is the causal agent of Rhizoctonia root and crown rot of sugar beet (Beta vulgaris) in North Dakota and Minnesota. This disease is a major limiting factor to sugar beet production. Management strategies currently include using partially resistant cultivars and fungicides. ...

78 FR 30829 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-23

... Promulgation of Air Quality Implementation Plans; Illinois; Air Quality Standards Revision AGENCY... the Illinois State Implementation Plan (SIP) to reflect current national ambient air quality standards...) 692-2450. 4. Mail: Pamela Blakley, Chief, Control Strategies Section, Air Programs Branch (AR-18J), U...

Mannosylated Lipoarabinomannan in serum as a biomarker candidate for subclinical bovine tuberculosis

USDA-ARS?s Scientific Manuscript database

Background: Early and unambiguous detection of bovine tuberculosis (bTB), a significant disease of cattle worldwide, is necessary to control the spread of infection to other animals and humans. Current testing strategies are laborious, time consuming and heavily reliant on host responses that do n...

Choline acetyltransferase in the hippocampus is associated with learning strategy preference in adult male rats.

PubMed

Hawley, Wayne R; Witty, Christine F; Daniel, Jill M; Dohanich, Gary P

2015-08-01

One principle of the multiple memory systems hypothesis posits that the hippocampus-based and striatum-based memory systems compete for control over learning. Consistent with this notion, previous research indicates that the cholinergic system of the hippocampus plays a role in modulating the preference for a hippocampus-based place learning strategy over a striatum-based stimulus--response learning strategy. Interestingly, in the hippocampus, greater activity and higher protein levels of choline acetyltransferase (ChAT), the enzyme that synthesizes acetylcholine, are associated with better performance on hippocampus-based learning and memory tasks. With this in mind, the primary aim of the current study was to determine if higher levels of ChAT and the high-affinity choline uptake transporter (CHT) in the hippocampus were associated with a preference for a hippocampus-based place learning strategy on a task that also could be solved by relying on a striatum-based stimulus--response learning strategy. Results confirmed that levels of ChAT in the dorsal region of the hippocampus were associated with a preference for a place learning strategy on a water maze task that could also be solved by adopting a stimulus-response learning strategy. Consistent with previous studies, the current results support the hypothesis that the cholinergic system of the hippocampus plays a role in balancing competition between memory systems that modulate learning strategy preference. Copyright © 2015 Elsevier B.V. All rights reserved.

Multi-Criteria Decision Making Approaches for Quality Control of Genome-Wide Association Studies

PubMed Central

Malovini, Alberto; Rognoni, Carla; Puca, Annibale; Bellazzi, Riccardo

2009-01-01

Experimental errors in the genotyping phases of a Genome-Wide Association Study (GWAS) can lead to false positive findings and to spurious associations. An appropriate quality control phase could minimize the effects of this kind of errors. Several filtering criteria can be used to perform quality control. Currently, no formal methods have been proposed for taking into account at the same time these criteria and the experimenter’s preferences. In this paper we propose two strategies for setting appropriate genotyping rate thresholds for GWAS quality control. These two approaches are based on the Multi-Criteria Decision Making theory. We have applied our method on a real dataset composed by 734 individuals affected by Arterial Hypertension (AH) and 486 nonagenarians without history of AH. The proposed strategies appear to deal with GWAS quality control in a sound way, as they lead to rationalize and make explicit the experimenter’s choices thus providing more reproducible results. PMID:21347174

Investigation of Inner Loop Flight Control Strategies for High-Speed Research

NASA Technical Reports Server (NTRS)

Newman, Brett; Kassem, Ayman

1999-01-01

This report describes the activities and findings conducted under contract NAS1-19858 with NASA Langley Research Center. Subject matter is the investigation of suitable flight control design methodologies and solutions for large, flexible high-speed vehicles. Specifically, methodologies are to address the inner control loops used for stabilization and augmentation of a highly coupled airframe system possibly involving rigid-body motion, structural vibrations, unsteady aerodynamics, and actuator dynamics. Techniques considered in this body of work are primarily conventional-based, and the vehicle of interest is the High-Speed Civil Transport (HSCT). Major findings include 1) current aeroelastic vehicle modeling procedures require further emphasis and refinement, 2) traditional and nontraditional inner loop flight control strategies employing a single feedback loop do not appear sufficient for highly flexible HSCT class vehicles, 3) inner loop flight control systems will, in all likelihood, require multiple interacting feedback loops, and 4) Ref. H HSCT configuration presents major challenges to designing acceptable closed-loop flight dynamics.

A continually online-trained neural network controller for brushless DC motor drives

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

Rubaai, A.; Kotaru, R.; Kankam, M.D.

2000-04-01

In this paper, a high-performance controller with simultaneous online identification and control is designed for brushless dc motor drives. The dynamics of the motor/load are modeled online, and controlled using two different neural network based identification and control schemes, as the system is in operation. In the first scheme, an attempt is made to control the rotor angular speed, utilizing a single three-hidden-layer network. The second scheme attempts to control the stator currents, using a predetermined control law as a function of the estimated states. This schemes incorporates three multilayered feedforward neural networks that are online trained, using the Levenburg-Marquadtmore » training algorithm. The control of the direct and quadrature components of the stator current successfully tracked a wide variety of trajectories after relatively short online training periods. The control strategy adapts to the uncertainties of the motor/load dynamics and, in addition, learns their inherent nonlinearities. Simulation results illustrated that a neurocontroller used in conjunction with adaptive control schemes can result in a flexible control device which may be utilized in a wide range of environments.« less

Mixed methods research in tobacco control with youth and young adults: A methodological review of current strategies.

PubMed

Fryer, Craig S; Seaman, Elizabeth L; Clark, Rachael S; Plano Clark, Vicki L

2017-01-01

Tobacco use among young people is a complex and serious global dilemma that demands innovative and diverse research approaches. The purpose of this methodological review was to examine the current use of mixed methods research in tobacco control with youth and young adult populations and to develop practical recommendations for tobacco control researchers interested in this methodology. Using PubMed, we searched five peer-reviewed journals that publish tobacco control empirical literature for the use of mixed methods research to study young populations, age 12-25 years. Our team analyzed the features of each article in terms of tobacco control topic, population, youth engagement strategies, and several essential elements of mixed methods research. We identified 23 mixed methods studies published by authors from five different countries reported between 2004 and 2015. These 23 articles examined various topics that included tobacco use behavior, tobacco marketing and branding, and cessation among youth and young adults. The most common mixed methods approach was variations of the concurrent design in which the qualitative and quantitative strands were administered at the same time and given equal priority. This review documented several innovative applications of mixed methods research as well as challenges in the reporting of the complex research designs. The use of mixed methods research in tobacco control has great potential for advancing the understanding of complex behavioral and sociocultural issues for all groups, especially youth and young adults.

Mixed methods research in tobacco control with youth and young adults: A methodological review of current strategies

PubMed Central

Seaman, Elizabeth L.; Clark, Rachael S.; Plano Clark, Vicki L.

2017-01-01

Introduction Tobacco use among young people is a complex and serious global dilemma that demands innovative and diverse research approaches. The purpose of this methodological review was to examine the current use of mixed methods research in tobacco control with youth and young adult populations and to develop practical recommendations for tobacco control researchers interested in this methodology. Methods Using PubMed, we searched five peer-reviewed journals that publish tobacco control empirical literature for the use of mixed methods research to study young populations, age 12–25 years. Our team analyzed the features of each article in terms of tobacco control topic, population, youth engagement strategies, and several essential elements of mixed methods research. Results We identified 23 mixed methods studies published by authors from five different countries reported between 2004 and 2015. These 23 articles examined various topics that included tobacco use behavior, tobacco marketing and branding, and cessation among youth and young adults. The most common mixed methods approach was variations of the concurrent design in which the qualitative and quantitative strands were administered at the same time and given equal priority. This review documented several innovative applications of mixed methods research as well as challenges in the reporting of the complex research designs. Conclusions The use of mixed methods research in tobacco control has great potential for advancing the understanding of complex behavioral and sociocultural issues for all groups, especially youth and young adults. PMID:28841689

Advanced model-based control strategies for the intensification of upstream and downstream processing in mAb production.

PubMed

Papathanasiou, Maria M; Quiroga-Campano, Ana L; Steinebach, Fabian; Elviro, Montaña; Mantalaris, Athanasios; Pistikopoulos, Efstratios N

2017-07-01

Current industrial trends encourage the development of sustainable, environmentally friendly processes with minimal energy and material consumption. In particular, the increasing market demand in biopharmaceutical industry and the tight regulations in product quality necessitate efficient operating procedures that guarantee products of high purity. In this direction, process intensification via continuous operation paves the way for the development of novel, eco-friendly processes, characterized by higher productivity and lower production costs. This work focuses on the development of advanced control strategies for (i) a cell culture system in a bioreactor and (ii) a semicontinuous purification process. More specifically, we consider a fed-batch culture of GS-NS0 cells and the semicontinuous Multicolumn Countercurrent Solvent Gradient Purification (MCSGP) for the purification process. The controllers are designed following the PAROC framework/software platform and their capabilities are assessed in silico, against the process models. It is demonstrated that the proposed controllers efficiently manage to increase the system productivity, returning strategies that can lead to continuous, stable process operation. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:966-988, 2017. © 2017 American Institute of Chemical Engineers.

New Worlds Observer Formation Control Design Based on the Dynamics of Relative Motion

NASA Technical Reports Server (NTRS)

Luquette, Richard J.

2008-01-01

The New Worlds Observer (NWO) mission is designed for the direct detection and characterization of extrasolar planets. The NWO mission concept employs a two spacecraft leader-follower formation on a trajectory around the Earth/Moon-Sun L(sub 2) Libration Point. The leader spacecraft is baselined as a 4 meter optical telescope. The follower, Starshade spacecraft, is designed to suppress light from a central body star permitting direct detection of a surrounding exoplanetary system. The current design requires a nominal leader-follower separation range of 72 Megameters. NWO poses many challenges including formation control. NWO cycles between three principal control modes during the nominal mission timeline: science (fine pointing), realignment and transition. This paper examines formation control strategies in the context of dynamics of relative motion for two spacecraft operating in the vicinity of the Earth/Moon-Sun L(sub 2)libration point. The paper presents an overview of the equations of relative motion followed by a discussion of each of the control modes. Discussion and analysis characterize control strategies for each of the mission control modes, including requirements, implementation challenges and project fuel budgets.

Wheel slip control with torque blending using linear and nonlinear model predictive control

NASA Astrophysics Data System (ADS)

Basrah, M. Sofian; Siampis, Efstathios; Velenis, Efstathios; Cao, Dongpu; Longo, Stefano

2017-11-01

Modern hybrid electric vehicles employ electric braking to recuperate energy during deceleration. However, currently anti-lock braking system (ABS) functionality is delivered solely by friction brakes. Hence regenerative braking is typically deactivated at a low deceleration threshold in case high slip develops at the wheels and ABS activation is required. If blending of friction and electric braking can be achieved during ABS events, there would be no need to impose conservative thresholds for deactivation of regenerative braking and the recuperation capacity of the vehicle would increase significantly. In addition, electric actuators are typically significantly faster responding and would deliver better control of wheel slip than friction brakes. In this work we present a control strategy for ABS on a fully electric vehicle with each wheel independently driven by an electric machine and friction brake independently applied at each wheel. In particular we develop linear and nonlinear model predictive control strategies for optimal performance and enforcement of critical control and state constraints. The capability for real-time implementation of these controllers is assessed and their performance is validated in high fidelity simulation.

China’s Comprehensive Approach: Refining the U.S. Targeting Process to Inform U.S. Strategy

DTIC Science & Technology

2018-04-20

control demonstrated by China, the subject matter expertise required to generate a comprehensive approach like China’s does exist. However, due to a vast...with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1...code) NATIONAL DEFENSE UNIVERSITY JOINT FORCES STAFF COLLEGE JOINT ADVANCED WARFIGHTING SCHOOL CHINA’S COMPREHENSIVE APPROACH

Short-term airing by natural ventilation - modeling and control strategies.

PubMed

Perino, M; Heiselberg, P

2009-10-01

The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates traditional mechanical ventilation components with natural ventilation devices, such as motorized windows and louvers. Among the various ventilation strategies that are currently available, buoyancy driven single-sided natural ventilation has proved to be very effective and can provide high air change rates for temperature and IAQ control. However, in order to promote a wider applications of these systems, an improvement in the knowledge of their working principles and the availability of new design and simulation tools is necessary. In this context, the paper analyses and presents the results of a research that was aimed at developing and validating numerical models for the analysis of buoyancy driven single-sided natural ventilation systems. Once validated, these models can be used to optimize control strategies in order to achieve satisfactory indoor comfort conditions and IAQ. Practical Implications Numerical and experimental analyses have proved that short-term airing by intermittent ventilation is an effective measure to satisfactorily control IAQ. Different control strategies have been investigated to optimize the capabilities of the systems. The proposed zonal model has provided good performances and could be adopted as a design tool, while CFD simulations can be profitably used for detailed studies of the pollutant concentration distribution in a room and to address local discomfort problems.

Decision making about healthcare-related tests and diagnostic test strategies. Paper 2: a review of methodological and practical challenges.

PubMed

Mustafa, Reem A; Wiercioch, Wojtek; Cheung, Adrienne; Prediger, Barbara; Brozek, Jan; Bossuyt, Patrick; Garg, Amit X; Lelgemann, Monika; Büehler, Diedrich; Schünemann, Holger J

2017-12-01

In this first of a series of five articles, we provide an overview of how and why healthcare-related tests and diagnostic strategies are currently applied. We also describe how our findings can be integrated with existing frameworks for making decisions that guide the use of healthcare-related tests and diagnostic strategies. We searched MEDLINE, references of identified articles, chapters in relevant textbooks, and identified articles citing classic literature on this topic. We provide updated frameworks for the potential roles and applications of tests with suggested definitions and practical examples. We also discuss study designs that are commonly used to assess tests' performance and the effects of tests on people's health. These designs include diagnostic randomized controlled trials and retrospective validation. We describe the utility of these and other currently suggested designs, which questions they can answer and which ones they cannot. In addition, we summarize the challenges unique to decision-making resulting from the use of tests. This overview highlights current challenges in the application of tests in decision-making in healthcare, provides clarifications, and informs the proposed solutions. Copyright © 2017 Elsevier Inc. All rights reserved.

New Perspectives on the Use of Phytochemicals as an Emergent Strategy to Control Bacterial Infections Including Biofilms.

PubMed

Borges, Anabela; Abreu, Ana Cristina; Dias, Carla; Saavedra, Maria José; Borges, Fernanda; Simões, Manuel

2016-07-05

The majority of current infectious diseases are almost untreatable by conventional antibiotic therapy given the advent of multidrug-resistant bacteria. The degree of severity and the persistence of infections are worsened when microorganisms form biofilms. Therefore, efforts are being applied to develop new drugs not as vulnerable as the current ones to bacterial resistance mechanisms, and also able to target bacteria in biofilms. Natural products, especially those obtained from plants, have proven to be outstanding compounds with unique properties, making them perfect candidates for these much-needed therapeutics. This review presents the current knowledge on the potentialities of plant products as antibiotic adjuvants to restore the therapeutic activity of drugs. Further, the difficulties associated with the use of the existing antibiotics in the treatment of biofilm-related infections are described. To counteract the biofilm resistance problems, innovative strategies are suggested based on literature data. Among the proposed strategies, the use of phytochemicals to inhibit or eradicate biofilms is highlighted. An overview on the use of phytochemicals to interfere with bacterial quorum sensing (QS) signaling pathways and underlying phenotypes is provided. The use of phytochemicals as chelating agents and efflux pump inhibitors is also reviewed.

The role of self-determined motivation in job search: A dynamic approach.

PubMed

da Motta Veiga, Serge P; Gabriel, Allison S

2016-03-01

Job search is a dynamic self-regulated process during which job seekers need to stay motivated to secure a job. However, past research has taken a relatively static approach to examining motivation during the job search, in addition to ignoring how the quality of one's motivation--ranging from autonomous to controlled--can influence job search processes. Adopting a within-person perspective, the current study extends self-determination theory (SDT) to the job search context to investigate (a) when autonomous and controlled motivations are more or less prevalent and (b) whether they influence job search effort through metacognitive strategies in differing ways depending upon the amount of time elapsed in the search. In a weekly study of new labor market entrants (Level-2 n = 149; Level-1 n = 691), results indicated that autonomous motivation decreased until the midpoint of the job search and then plateaued, whereas controlled motivation remained stable. Results also showed that autonomous motivation had a consistent, positive relation with metacognitive strategies, whereas the relation between controlled motivation and such strategies was negative early in the job search, but became positive as the job search progressed. Finally, the effects of motivation on job search effort occurred via metacognitive strategies differentially depending upon the time elapsed in the search. Combined, we provide a first glimpse into the dynamics of self-determined motivation on job search processes. (c) 2016 APA, all rights reserved).

Domestic returns from investment in the control of tuberculosis in other countries.

PubMed

Schwartzman, Kevin; Oxlade, Olivia; Barr, R Graham; Grimard, Franque; Acosta, Ivelisse; Baez, Jeannette; Ferreira, Elizabeth; Melgen, Ricardo Elías; Morose, Willy; Salgado, Arturo Cruz; Jacquet, Vary; Maloney, Susan; Laserson, Kayla; Mendez, Ariel Pablos; Menzies, Dick

2005-09-08

We hypothesized that investments to improve the control of tuberculosis in selected high-incidence countries would prove to be cost saving for the United States by reducing the incidence of the disease among migrants. Using decision analysis, we estimated tuberculosis-related morbidity, mortality, and costs among legal immigrants and refugees, undocumented migrants, and temporary visitors from Mexico after their entry into the United States. We assessed the current strategy of radiographic screening of legal immigrants plus current tuberculosis-control programs alone and with the addition of either U.S.-funded expansion of the strategy of directly observed treatment, short course (DOTS), in Mexico or tuberculin skin testing to screen legal immigrants from Mexico. We also examined tuberculosis-related outcomes among migrants from Haiti and the Dominican Republic using the same three strategies. As compared with the current strategy, expanding the DOTS program in Mexico at a cost to the United States of 34.9 million dollars would result in 2591 fewer cases of tuberculosis in the United States, with 349 fewer deaths from the disease and net discounted savings of 108 million dollars over a 20-year period. Adding tuberculin skin testing to radiographic screening of legal immigrants from Mexico would result in 401 fewer cases of tuberculosis in the United States but would cost an additional 329 million dollars. Expansion of the DOTS program would remain cost saving even if the initial investment were doubled, if the United States paid for all antituberculosis drugs in Mexico, or if the decline in the incidence of tuberculosis in Mexico was less than projected. A 9.4 million dollars investment to expand the DOTS program in Haiti and the Dominican Republic would result in net U.S. savings of 20 million dollars over a 20-year period. U.S.-funded efforts to expand the DOTS program in Mexico, Haiti, and the Dominican Republic could reduce tuberculosis-related morbidity and mortality among migrants to the United States, producing net cost savings for the United States. Copyright 2005 Massachusetts Medical Society.

Peptide and low molecular weight proteins based kidney targeted drug delivery systems.

PubMed

Xu, Pengfei; Zhang, Hailiang; Dang, Ruili; Jiang, Pei

2018-05-30

Renal disease is a worldwide public health problem, and unfortunately, the therapeutic index of regular drugs is limited. Thus, it is a great need to develop effective treatment strategies. Among the reported strategies, kidney-targeted drug delivery system is a promising method to increase renal efficacy and reduce extra-renal toxicity. In recent years, working as vehicles for targeted drug delivery, low molecular weight proteins (LMWP) and peptide have received immense attention due to their many advantages, such as selective accumulation in kidney, high drug loading capability, control over routes of biodegradation, convenience in modification at the amino terminus, and good biocompatibility. In this review, we describe the current LMWP and peptide carriers for kidney targeted drug delivery systems. In addition, we discuss different linking strategies between carriers and drugs. Furthermore, we briefly outline the current status and attempt to give an outlook on the further study. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Targeting eukaryotic Rab proteins: a smart strategy for chlamydial survival and replication.

PubMed

Damiani, María Teresa; Gambarte Tudela, Julián; Capmany, Anahí

2014-09-01

Chlamydia, an obligate intracellular bacterium which passes its entire lifecycle within a membrane-bound vacuole called the inclusion, has evolved a variety of unique strategies to establish an advantageous intracellular niche for survival. This review highlights the mechanisms by which Chlamydia subverts vesicular transport in host cells, particularly by hijacking the master controllers of eukaryotic trafficking, the Rab proteins. A subset of Rabs and Rab interacting proteins that control the recycling pathway or the biosynthetic route are selectively recruited to the chlamydial inclusion membrane. By interfering with Rab-controlled transport steps, this intracellular pathogen not only prevents its own degradation in the phagocytic pathway, but also creates a favourable intracellular environment for growth and replication. Chlamydia, a highly adapted and successful intracellular pathogen, has several redundant strategies to re-direct vesicles emerging from biosynthetic compartments that carry host molecules essential for bacterial development. Although current knowledge is limited, the latest findings have shed light on the role of Rab proteins in the course of chlamydial infections and could open novel opportunities for anti-chlamydial therapy. © 2014 John Wiley & Sons Ltd.

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

PubMed

Chidawanyika, Frank; Mudavanhu, Pride; Nyamukondiwa, Casper

2012-11-09

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

Simulation of Cross-border Impacts Resulting from Classical Swine Fever Epidemics within the Netherlands and Germany.

PubMed

Hop, G E; Mourits, M C M; Oude Lansink, A G J M; Saatkamp, H W

2016-02-01

The cross-border region of the Netherlands (NL) and the two German states of North Rhine Westphalia (NRW) and Lower Saxony (LS) is a large and highly integrated livestock production area. This region increasingly develops towards a single epidemiological area in which disease introduction is a shared veterinary and, consequently, economic risk. The objectives of this study were to examine classical swine fever (CSF) control strategies' veterinary and direct economic impacts for NL, NRW and LS given the current production structure and to analyse CSF's cross-border causes and impacts within the NL-NRW-LS region. The course of the epidemic was simulated by the use of InterSpread Plus, whereas economic analysis was restricted to calculating disease control costs and costs directly resulting from the control measures applied. Three veterinary control strategies were considered: a strategy based on the minimum EU requirements, a vaccination and a depopulation strategy based on NL and GER's contingency plans. Regardless of the veterinary control strategy, simulated outbreak sizes and durations for 2010 were much smaller than those simulated previously, using data from over 10 years ago. For example, worst-case outbreaks (50th percentile) in NL resulted in 30-40 infected farms and lasted for two to four and a half months; associated direct costs and direct consequential costs ranged from €24.7 to 28.6 million and €11.7 to 26.7 million, respectively. Both vaccination and depopulation strategies were efficient in controlling outbreaks, especially large outbreaks, whereas the EU minimum strategy was especially deficient in controlling worst-case outbreaks. Both vaccination and depopulation strategies resulted in low direct costs and direct consequential costs. The probability of cross-border disease spread was relatively low, and cross-border spread resulted in small, short outbreaks in neighbouring countries. Few opportunities for further cross-border harmonization and collaboration were identified, including the implementation of cross-border regions (free and diseased regions regardless of the border) in case of outbreaks within close proximity of the border, and more and quicker sharing of information across the border. It was expected, however, that collaboration to mitigate the market effects of an epidemic will create more opportunities to lower the impact of CSF outbreaks in a cross-border context. © 2014 Blackwell Verlag GmbH.

Comparison of a math fact rehearsal and a mnemonic strategy approach for improving math fact fluency.

PubMed

Nelson, Peter M; Burns, Matthew K; Kanive, Rebecca; Ysseldyke, James E

2013-12-01

The current study used a randomized controlled trial to compare the effects of a practice-based intervention and a mnemonic strategy intervention on the retention and application of single-digit multiplication facts with 90 third- and fourth-grade students with math difficulties. Changes in retention and application were assessed separately using one-way ANCOVAs in which students' pretest scores were included as the covariate. Students in the practice-based intervention group had higher retention scores (expressed as the total number of digits correct per minute) relative to the control group. No statistically significant between-group differences were observed for application scores. Practical and theoretical implications for interventions targeting basic multiplication facts are discussed. © 2013.

A precisely targeted application strategy of dipping young cucumber fruit in fungicide to control cucumber gray mold.

PubMed

He, Leiming; Cui, Kaidi; Song, Yufei; Zhang, Zhengqun; Li, Beixing; Mu, Wei; Liu, Feng

2018-04-27

Gray mold is a ubiquitous destructive plant disease worldwide. To avoid the shortcomings of conventional spraying systems for controlling this disease, such as high selection pressure on Botrytis cinerea for resistance and fungicide waste resulting from spray drift, a precisely targeted application strategy of dipping young cucumber fruit in a mixture of fungicide and forchlorfenuron (plant growth regulator, PGR) during the bloom period to control cucumber gray mold was developed in the current study. Without leaving above-limit residues in cucumber fruits, dipping in fludioxonil at 30 mg liter -1 provided a greater efficacy (85.4%) against cucumber gray mold than did spraying at 100 mg liter -1 (76.4%). Importantly, fludioxonil mixed with forchlorfenuron from 25 to 35 mg liter -1 increased the yield of cucumbers by 26.2%-36.7% compared to dipping fruit only in forchlorfenuron. The increased yield may be a benefit of controlling gray mold. Dipping fruit in fungicides and PGRs seems to be a potential precisely targeted application strategy to not only control cucumber gray mold effectively but also, through the action of PGRs, to increase the cucumber yield. This novel application method is believed to have a bright prospect in cucumber production in Chinese solar greenhouses. This article is protected by copyright. All rights reserved.

Physics conditions for robust control of tearing modes in a rotating tokamak plasma

NASA Astrophysics Data System (ADS)

Lazzaro, E.; Borgogno, D.; Brunetti, D.; Comisso, L.; Fevrier, O.; Grasso, D.; Lutjens, H.; Maget, P.; Nowak, S.; Sauter, O.; Sozzi, C.; the EUROfusion MST1 Team

2018-01-01

The disruptive collapse of the current sustained equilibrium of a tokamak is perhaps the single most serious obstacle on the path toward controlled thermonuclear fusion. The current disruption is generally too fast to be identified early enough and tamed efficiently, and may be associated with a variety of initial perturbing events. However, a common feature of all disruptive events is that they proceed through the onset of magnetohydrodynamic instabilities and field reconnection processes developing magnetic islands, which eventually destroy the magnetic configuration. Therefore the avoidance and control of magnetic reconnection instabilities is of foremost importance and great attention is focused on the promising stabilization techniques based on localized rf power absorption and current drive. Here a short review is proposed of the key aspects of high power rf control schemes (specifically electron cyclotron heating and current drive) for tearing modes, considering also some effects of plasma rotation. From first principles physics considerations, new conditions are presented and discussed to achieve control of the tearing perturbations by means of high power ({P}{{EC}}≥slant {P}{{ohm}}) in regimes where strong nonlinear instabilities may be driven, such as secondary island structures, which can blur the detection and limit the control of the instabilities. Here we consider recent work that has motivated the search for the improvement of some traditional control strategies, namely the feedback schemes based on strict phase tracking of the propagating magnetic islands.

Implications of life-history strategies for obesity

PubMed Central

Maner, Jon K.; Dittmann, Andrea; Meltzer, Andrea L.; McNulty, James K.

2017-01-01

The association between low socioeconomic status (SES) and obesity is well documented. In the current research, a life history theory (LHT) framework provided an explanation for this association. Derived from evolutionary behavioral science, LHT emphasizes how variability in exposure to unpredictability during childhood gives rise to individual differences in a range of social psychological processes across the life course. Consistent with previous LHT research, the current findings suggest that exposure to unpredictability during childhood (a characteristic common to low SES environments) is associated with the adoption of a fast life-history strategy, one marked by impulsivity and a focus on short-term goals. We demonstrate that a fast life-history strategy, in turn, was associated with dysregulated weight-management behaviors (i.e., eating even in the absence of hunger), which were predictive of having a high body mass index (BMI) and being obese. In both studies, findings held while controlling for participants’ current socioeconomic status, suggesting that obesity is rooted in childhood experiences. A serial mediation model in study 2 confirmed that effects of childhood SES on adult BMI and obesity can be explained in part by exposure to unpredictability, the adoption of a fast life-history strategy, and dysregulated-eating behaviors. These findings suggest that weight problems in adulthood may be rooted partially in early childhood exposure to unpredictable events and environments. LHT provides a valuable explanatory framework for understanding the root causes of obesity. PMID:28739939

Cognitive training of self-initiation of semantic encoding strategies in schizophrenia: A pilot study.

PubMed

Guimond, Synthia; Lepage, Martin

2016-01-01

Available cognitive remediation interventions have a significant but relatively small to moderate impact on episodic memory in schizophrenia. The present study aimed to evaluate the efficacy and feasibility of a brief novel episodic memory training targeting the self-initiation of semantic encoding strategies. To select patients with such deficits, 28 participants with schizophrenia performed our Semantic Encoding Memory Task (SEMT) that provides a measure of self-initiated semantic encoding strategies. This task identified a deficit in 13 participants who were then offered two 60-minute training sessions one week apart. After the training, patients performed an alternate version of the SEMT. The CVLT-II (a standardised measure of semantic encoding strategies) and the BVMT-R (a control spatial memory task) were used to quantify memory pre- and post-training. After the training, participants were significantly better at self-initiating semantic encoding strategies in the SEMT (p = .004) and in the CVLT-II (p = .002). No significant differences were found in the BVMT-R. The current study demonstrates that a brief and specific training in memory strategies can help patients to improve a deficient memory process in schizophrenia. Future studies will need to test this intervention further using a randomised controlled trial, and to explore its functional impact.

Control of cervical cancer in Peru: Current barriers and challenges for the future.

PubMed

Aguilar, Alfredo; Pinto, Joseph A; Araujo, Jhajaira; Fajardo, Williams; Bravo, Leny; Pinillos, Luis; Vallejos, Carlos

2016-08-01

Cervical cancer is the leading malignant neoplasm in Peruvian women. This malignancy is a public health problem and several efforts were previously performed to develop cancer control plans. Geographical, cultural, structural, infrastructural and procedural barriers can limit the implementation of such strategies. Several previous studies have characterized human papilloma virus (HPV) epidemiology, where prevalence of high-risk HPV in adult females is ~12% and the prevalence in cervical cancer is 90-95%. The predominant barriers for the control of cervical cancer are lack of specialists in remote villages, education/cultural issues, loss of patients in follow-up, lack of access to HPV testing and lack of compliance for HPV vaccination. A good strategy for the prevention and early detection of high-risk HPV, pre-malignant neoplasms and cervical cancer, identified by interventional studies, is the self-sampling test, which assists with overcoming the cultural and geographic barriers. The current cancer control plan, termed 'Plan Esperanza', is performed with massive training of health professionals and social sensitization campaigns leading to filling the gaps regarding education and, in addition, it provides cancer care coverage for poorer individuals. In our experience at Oncosalud-AUNA, with a cohort of ~750,000 affiliates using a pre-paid system with annual screenings for cervical cancer for women, offered free-of-charge, a lower incidence of this malignancy (5.8/100,000) is now observed compared with the national incidence (32.7/100,000). As in other countries, the HPV vaccination can be a cost-utility strategy to reduce the high burdens of cervical cancer in Peru, a rapid and cheap HPV molecular sub-typification is rapidly required.

The Wild Side of Disease Control at the Wildlife-Livestock-Human Interface: A Review

PubMed Central

Gortazar, Christian; Diez-Delgado, Iratxe; Barasona, Jose Angel; Vicente, Joaquin; De La Fuente, Jose; Boadella, Mariana

2015-01-01

The control of diseases shared with wildlife requires the development of strategies that will reduce pathogen transmission between wildlife and both domestic animals and human beings. This review describes and criticizes the options currently applied and attempts to forecast wildlife disease control in the coming decades. Establishing a proper surveillance and monitoring scheme (disease and population wise) is the absolute priority before even making the decision as to whether or not to intervene. Disease control can be achieved by different means, including: (1) preventive actions, (2) arthropod vector control, (3) host population control through random or selective culling, habitat management or reproductive control, and (4) vaccination. The alternative options of zoning or no-action should also be considered, particularly in view of a cost/benefit assessment. Ideally, tools from several fields should be combined in an integrated control strategy. The success of disease control in wildlife depends on many factors, including disease ecology, natural history, and the characteristics of the pathogen, the availability of suitable diagnostic tools, the characteristics of the domestic and wildlife host(s) and vectors, the geographical spread of the problem, the scale of the control effort and stakeholders’ attitudes. PMID:26664926

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

NASA Astrophysics Data System (ADS)

Wu, Xiaojuan; Gao, Danhui

2017-10-01

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

Role of oral pre-exposure prophylaxis (PrEP) in current and future HIV prevention strategies.

PubMed

Burns, David N; Grossman, Cynthia; Turpin, Jim; Elharrar, Vanessa; Veronese, Fulvia

2014-12-01

Treatment as prevention is expected to have a major role in reducing HIV incidence, but other prevention interventions will also be required to bring the epidemic under control, particularly among key populations. One or more forms of pre-exposure prophylaxis (PrEP) will likely play a critical role. Oral PrEP with emtricitabine-tenofovir (Truvada®) is currently available in the US and some other countries, but uptake has been slow. We review the concerns that have contributed to this slow uptake and discuss current and future research in this critical area of HIV prevention research.

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

PubMed Central

2009-01-01

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

Shielding Strategies for Human Space Exploration

NASA Technical Reports Server (NTRS)

Wilson J. W. (Editor); Miller, J. (Editor); Konradi, A. (Editor); Cucinotta, F. A. (Editor)

1997-01-01

A group of twenty-nine scientists and engineers convened a 'Workshop on Shielding Strategies for Human Space Exploration' at the Lyndon B. Johnson Space Center in Houston, Texas. The provision of shielding for a Mars mission or a Lunar base from the hazards of space radiations is a critical technology since astronaut radiation safety depends on it and shielding safety factors to control risk uncertainty appear to be great. The purpose of the workshop was to define requirements for the development and evaluation of high performance shield materials and designs and to develop ideas regarding approaches to radiation shielding. The workshop was organized to review the recent experience on shielding strategies gained in studies of the 'Space Exploration Initiative (SEI),' to review the current knowledge base for making shield assessment, to examine a basis for new shielding strategies, and to recommend a strategy for developing the required technologies for a return to the moon or for Mars exploration. The uniqueness of the current workshop arises from the expected long duration of the missions without the protective cover of the geomagnetic field in which the usually small and even neglected effects of the galactic cosmic rays (GCR) can no longer be ignored. It is the peculiarity of these radiations for which the inter-action physics and biological action are yet to be fully understood.

Development of the New Zealand strategy for local eradication of tuberculosis from wildlife and livestock

PubMed Central

Livingstone, PG; Hancox, N; Nugent, G; Mackereth, G; Hutchings, SA

2015-01-01

Abstract We describe the progressive development of New Zealand's national strategy for control of tuberculosis (TB) in its agricultural sector over the last four decades. The strategy is globally unique, reflecting the need for effective and co-ordinated management of TB in a wildlife maintenance host, the brushtail possum (Trichosurus vulpecula), in addition to controlling infection in cattle and farmed deer herds. Since the early 1990s, the strategy has been developed by the Animal Health Board (AHB), formed to empower the farming industry to take the leadership role in funding of TB control, policy development and administration. The AHB became the first non-government organisation to develop and gain acceptance by the funders (farming industry and government) of a National Pest Management Strategy (NPMS) under the Biosecurity Act 1993. A key outcome of the NPMS for TB control was the development and inclusion of very challenging objectives that provided direction for management, research and possum control. This paper describes the process whereby the NPMS was revised twice, following achievement of each successive set of strategy objectives within budget. Success was based on firstly, reorganisation of the AHB and its operational systems to achieve increased efficiency; secondly, improved efficiency through contracting possum and disease control, and thirdly research delivering effective and practical applications, while also providing a scientific basis for setting directions for future control strategies. The last revision of the NPMS was implemented in 2011, and included objectives to eradicate Mycobacterium bovis-infected wildlife populations over 2.5 million hectares by 2026. This ambitious objective was adopted only after extensive forecast modelling enabled stakeholders to identify and select the most cost-effective long-term solution for the management of M. bovis-infected possum populations. The accomplishment of New Zealand's TB control programme, in meeting successive sets of demanding NPMS objectives, has seen a 95% decrease in the number of infected cattle and deer herds since they peaked at 1,694 in 1994, and the eradication of TB from infected possum populations from 830,000 hectares. Provided the current level of funding continues, New Zealand is positioned to achieve national eradication of TB well in advance of the 40–50-year timeline forecast 3 years ago. PMID:25651829

Illicit drugs policy through the lens of regulation.

PubMed

Ritter, Alison

2010-07-01

The application of regulatory theory to the problem of illicit drugs has generally been thought about only in terms of 'command and control'. The international treaties governing global illicit drug control and the use of law enforcement to dissuade and punish offenders have been primary strategies. In this paper I explore the application of other aspects of regulatory theory to illicit drugs-primarily self-regulation and market regulation. There has been an overreliance on strategies from the top of the regulatory pyramid. Two other regulatory strategies--self-regulation and market regulation--can be applied to illicit drugs. Self-regulation, driven by the proactive support of consumer groups may reduce drug-related harms. Market strategies such as pill-testing can change consumer preferences and encourage alternate seller behaviour. Regulatory theory is also concerned with partnerships between the state and third parties: strategies in these areas include partnerships between police and pharmacies regarding sale of potential precursor chemicals. Regulatory theory and practice is a rich and well-developed field in the social sciences. I argue that governments should consider the full array of regulatory strategies. Using regulatory theory provides a rationale and justification to strategies that are currently at the whim of politics, such as funding for user groups. The greater application of regulatory approaches may produce more flexible and structured illicit drug policies. Copyright (c) 2009 Elsevier B.V. All rights reserved.

A conceptual framework for the sustainable management of wastewater in Harare, Zimbabwe.

PubMed

Nhapi, I; Gijzen, H J; Siebel, M A

2003-01-01

The aim of this study was to formulate an integrated wastewater management model for Harare, Zimbabwe, based on current thinking. This implies that wastewater is treated/disposed of as close to the source of generation as possible. Resource recovery and reuse in a local thriving urban agriculture are integrated into this model. Intervention strategies were considered for controlling water, nitrogen and phosphorus flows to the lake. In the formulation of strategies, Harare was divided into five major operational areas of high-, medium-, and low-density residential areas, and also commercial and industrial areas. Specific options were then considered to suit landuse, development constraints and socio-economic status for each area, within the overall criteria of limiting nutrient inflows into the downstream Lake Chivero. Flexible and differential solutions were developed in relation to built environment, population density, composition of users, ownership, future environmental demands, and technical, environmental, hygienic, social and organisational factors. Options considered include source control by the users (residents, industries, etc.), using various strategies like implementation of toilets with source separation, and natural methods of wastewater treatment. Other possible strategies are invoking better behaviour through fees and information, incentives for cleaner production, and user responsibility through education, legislative changes and stricter controls over industry.

Evaluating long-term effectiveness of sleeping sickness control measures in Guinea.

PubMed

Pandey, Abhishek; Atkins, Katherine E; Bucheton, Bruno; Camara, Mamadou; Aksoy, Serap; Galvani, Alison P; Ndeffo-Mbah, Martial L

2015-10-22

Human African Trypanosomiasis threatens human health across Africa. The subspecies T.b. gambiense is responsible for the vast majority of reported HAT cases. Over the past decade, expanded control efforts accomplished a substantial reduction in HAT transmission, spurring the WHO to include Gambian HAT on its roadmap for 2020 elimination. To inform the implementation of this elimination goal, we evaluated the likelihood that current control interventions will achieve the 2020 target in Boffa prefecture in Guinea, which has one of the highest prevalences for HAT in the country, and where vector control measures have been implemented in combination with the traditional screen and treat strategy. We developed a three-species mathematical model of HAT and used a Bayesian melding approach to calibrate the model to epidemiological and entomological data from Boffa. From the calibrated model, we generated the probabilistic predictions regarding the likelihood that the current HAT control programs could achieve elimination by 2020 in Boffa. Our model projections indicate that if annual vector control is implemented in combination with annual or biennial active case detection and treatment, the probability of eliminating HAT as public health problem in Boffa by 2020 is over 90%. Annual implementation of vector control alone has a significant impact but a decreased chance of reaching the objective (77%). However, if the ongoing control efforts are interrupted, HAT will continue to remain a public health problem. In the presence of a non-human animal transmission reservoir, intervention strategies must be maintained at high coverage, even after 2020 elimination, to prevent HAT reemerging as a public health problem. Complementing active screening and treatment with vector control has the potential to achieve the elimination target before 2020 in the Boffa focus. However, surveillance must continue after elimination to prevent reemergence.

Impact of Automation Support on the Conflict Resolution Task in a Human-in-the-Loop Air Traffic Control Simulation

NASA Technical Reports Server (NTRS)

Mercer, Joey; Gomez, Ashley; Gabets, Cynthia; Bienert, Nancy; Edwards, Tamsyn; Martin, Lynne; Gujral, Vimmy; Homola, Jeffrey

2016-01-01

To determine the capabilities and limitations of human operators and automation in separation assurance roles, the second of three Human-in-the-Loop (HITL) part-task studies investigated air traffic controllers ability to detect and resolve conflicts under varying task sets, traffic densities, and run lengths. Operations remained within a single sector, staffed by a single controller, and explored, among other things, the controllers responsibility for conflict resolution with or without their involvement in the conflict detection task. Furthermore, these conditions were examined across two different traffic densities; 1x (current-day traffic) and a 20 increase above current-day traffic levels (1.2x). Analyses herein offer an examination of the conflict resolution strategies employed by controllers. In particular, data in the form of elapsed time between conflict detection and conflict resolution are used to assess if, and how, the controllers involvement in the conflict detection task affected the way in which they resolved traffic conflicts.

The strategic framework of tuberculosis control and prevention in the elderly: a scoping review towards End TB targets.

PubMed

Li, Jun; Chung, Pui-Hong; Leung, Cyrus L K; Nishikiori, Nobuyuki; Chan, Emily Y Y; Yeoh, Eng-Kiong

2017-06-01

With the rapid pace of population ageing, tuberculosis (TB) in the elderly increasingly becomes a public health challenge. Despite the increasing burden and high risks for TB in the elderly, targeted strategy has not been well understood and evaluated. We undertook a scoping review to identify current TB strategies, research and policy gaps in the elderly and summarized the results within a strategic framework towards End TB targets. Databases of Embase, MEDLINE, Global health and EBM reviews were searched for original studies, review articles, and policy papers published in English between January 1990 and December 2015. Articles examining TB strategy, program, guideline or intervention in the elderly from public health perspective were included.Nineteen articles met the inclusion criteria. Most of them were qualitative studies, issued in high- and middle-income countries and after 2000. To break the chain of TB transmission and reactivation in the elderly, infection control, interventions of avoiding delay in diagnosis and containment are essential for preventing transmission, especially in elderly institutions and aged immigrants; screening of latent TB infection and preventive therapy had effective impacts on reducing the risk of reactivation and should be used less reluctantly in older people; optimizing early case-finding with a high index of suspicion, systematic screening for prioritized high-risk groups, initial empirical and adequate follow-up treatment with close monitoring and evaluation, as well as enhanced programmatic management are fundamental pillars for active TB elimination. Evaluation of TB epidemiology, risk factors, impacts and cost-effectiveness of interventions, adopting accurate and rapid diagnostic tools, shorter and less toxic preventive therapy, are critical issues for developing strategy in the elderly towards End TB targets.TB control strategies in the elderly were comprehensively mapped in a causal link pathway. The framework and principals identified in this study will help to evaluate and improve current program, develop targeted strategy, as well as raise more discussions on the research priority settings and policy transitions. Given the scarceness of policy and evaluated interventions, as well as the unawareness of shifting TB epidemiology and strategy especially in developing countries, the increasing need of a ready TB program for the elderly warrants further research.

An Update on Tobacco Control Initiatives in Comprehensive Cancer Control Plans

PubMed Central

Dunne, Katherine; Henderson, Susan; Stewart, Sherri L.; Moore, Angela; Hayes, Nikki S.; Jordan, Jerelyn

2013-01-01

Introduction Comprehensive cancer control (CCC) coalitions address tobacco use, the leading cause of preventable death in the United States, through formal plans to guide tobacco control activities and other cancer prevention strategies. Best Practices for Comprehensive Tobacco Control Programs (Best Practices) and The Guide to Community Preventive Services (The Community Guide) are used to assist with this effort. We examined CCC plans to determine the extent to which they followed the Centers for Disease Control and Prevention’s (CDC’s) tobacco control and funding recommendations. Methods We obtained 69 CCC plans, current as of August 1, 2011, to determine which CDC recommendations from Best Practices and The Community Guide were incorporated. Data were abstracted through a content review and key word search and then summarized across the plans with dichotomous indicators. Additionally, we analyzed plans for inclusion of tobacco control funding goals and strategies. Results CCC plans incorporated a mean 4.5 (standard deviation [SD], 2.1) of 5 recommendations from Best Practices and 5.2 (SD, 0.9) of 10 recommendations from The Community Guide. Two-thirds of plans (66.7%) addressed funding for tobacco control as a strategy or action item; 47.8% of those plans (31.9% of total) defined a specific, measurable funding goal. Conclusion Although most CCC plans follow CDC-recommended tobacco control recommendations and funding levels, not all recommendations are addressed by every plan and certain recommendations are addressed in varying numbers of plans. Clearer prioritization of tobacco control recommendations by CDC may improve the extent to which they are followed and therefore maximize their public health benefit. PMID:23806802

Global tobacco prevention and control in relation to a cardiovascular health promotion and disease prevention framework: A narrative review.

PubMed

Carroll, Allison J; Labarthe, Darwin R; Huffman, Mark D; Hitsman, Brian

2016-12-01

The purpose of this review is to emphasize the role of tobacco prevention and control in cardiovascular health (CVH) promotion and cardiovascular disease (CVD) prevention, including the importance of these endpoints for measuring the full impact of tobacco-related policies, programs, and practices. In this review, we describe an overview of tobacco control interventions that have led to substantial declines in tobacco use and the relationship between these declines with CVH and CVD. We review interventions that have had success in high-income countries (HICs) as well as those that are gaining traction in low- and middle-income countries (LMICs). We emphasize the challenges to comprehensive tobacco prevention and control strategies faced by LMICs, and highlight the special role of cardiovascular health professionals in achieving CVH promotion and CVD prevention endpoints through tobacco control. Tobacco prevention and control strategies have a strong scientific basis, yet a distinct gap remains between this evidence and implementation of tobacco control policies, particularly in LMICs. Health professionals can contribute to tobacco control efforts, especially through patient-level clinical interventions, when supported by a health care system and government that recognize and support tobacco control as a critical strategy for CVH promotion and CVD prevention. Understanding, supporting, and applying current and evolving policies, programs, and practices in tobacco prevention and control is the province of all health professionals, especially those concerned with CVH promotion and CVD prevention. A new tobacco control roadmap from the World Heart Federation provides a strong impetus to the needed interdisciplinary collaboration. Copyright © 2016 Elsevier Inc. All rights reserved.

Global tobacco prevention and control in relation to a cardiovascular health promotion and disease prevention framework: A narrative review

PubMed Central

Carroll, Allison J.; Labarthe, Darwin R.; Huffman, Mark D.; Hitsman, Brian

2016-01-01

The purpose of this review is to emphasize the role of tobacco prevention and control in cardiovascular health (CVH) promotion and cardiovascular disease (CVD) prevention, including the importance of these endpoints for measuring the full impact of tobacco-related policies, programs, and practices. In this review, we describe an overview of tobacco control interventions that have led to substantial declines in tobacco use and the relationship between these declines with CVH and CVD. We review interventions that have had success in high-income countries (HICs) as well as those that are gaining traction in low- and middle-income countries (LMICs). We emphasize the challenges to comprehensive tobacco prevention and control strategies faced by LMICs, and highlight the special role of cardiovascular health professionals in achieving CVH promotion and CVD prevention endpoints through tobacco control. Tobacco prevention and control strategies have a strong scientific basis, yet a distinct gap remains between this evidence and implementation of tobacco control policies, particularly in LMICs. Health professionals can contribute to tobacco control efforts, especially through patient-level clinical interventions, when supported by a health care system and government that recognize and support tobacco control as a critical strategy for CVH promotion and CVD prevention. Understanding, supporting, and applying current and evolving policies, programs, and practices in tobacco prevention and control is the province of all health professionals, especially those concerned with CVH promotion and CVD prevention. A new tobacco control roadmap from the World Heart Federation provides a strong impetus to the needed interdisciplinary collaboration. PMID:27717667

[Recruitment of smokers in the Rio de Janeiro subway, Brazil, as a strategy to increase access to quitline services: the impact of novelty].

PubMed

Szklo, André Salem; Coutinho, Evandro da Silva Freire; Barros, Helena Maria Tannhauser; Perez, Cristina; Moreira, Taís de Campos; Figueiró, Luciana Rizzieri; Pinho, Mariana; Carvalho, Valeska Figueiredo

2009-11-01

Creative and innovative strategies to recruit smokers are essential for improving tobacco control activities. Currently in Brazil, through health warning messages on cigarette packs, there is a permanent and intense spread of messages that provoke feelings of loss associated with smoking, which is important to encourage access to smoking quitlines. The study analyzed the call rate for telephone counseling after introducing a new strategy for reactive recruitment focused on the theme 'smoking causes shortness of breath', adapted to the subway setting in Rio de Janeiro, as compared to the rates for two existing reactive strategies. Regardless of age bracket, there was a higher response to the new proposed strategy. Despite the major awareness-raising in Brazil concerning the ills of tobacco, new communications formats approaching personally relevant themes can increase the number and range of smokers recruited for telephone counseling to support cessation.

Model-based iterative learning control of Parkinsonian state in thalamic relay neuron

NASA Astrophysics Data System (ADS)

Liu, Chen; Wang, Jiang; Li, Huiyan; Xue, Zhiqin; Deng, Bin; Wei, Xile

2014-09-01

Although the beneficial effects of chronic deep brain stimulation on Parkinson's disease motor symptoms are now largely confirmed, the underlying mechanisms behind deep brain stimulation remain unclear and under debate. Hence, the selection of stimulation parameters is full of challenges. Additionally, due to the complexity of neural system, together with omnipresent noises, the accurate model of thalamic relay neuron is unknown. Thus, the iterative learning control of the thalamic relay neuron's Parkinsonian state based on various variables is presented. Combining the iterative learning control with typical proportional-integral control algorithm, a novel and efficient control strategy is proposed, which does not require any particular knowledge on the detailed physiological characteristics of cortico-basal ganglia-thalamocortical loop and can automatically adjust the stimulation parameters. Simulation results demonstrate the feasibility of the proposed control strategy to restore the fidelity of thalamic relay in the Parkinsonian condition. Furthermore, through changing the important parameter—the maximum ionic conductance densities of low-threshold calcium current, the dominant characteristic of the proposed method which is independent of the accurate model can be further verified.

A control strategy for PV stand-alone applications

NASA Astrophysics Data System (ADS)

Slouma, S.; Baccar, H.

2015-04-01

This paper proposes a stand-alone photovoltaic (PV) system study in domestic applications. Because of the decrease in power of photovoltaic module as a consequence of changes in solar radiation and temperature which affect the photovoltaic module performance, the design and control of DC-DC buck converter was proposed for providing power to the load from a photovoltaic source.In fact, the control of this converter is carried out with integrated MPPT (Maximum Power Point Tracking) algorithm which ensures a maximum energy generated by the PV arrays. Moreover, the output stage is composed by a battery energy storage system, dc-ac inverter, LCL filter which enables higher efficiency, low distortion ac waveforms and low leakage currents. The control strategy adopted is cascade control composed by two regulation loops.Simulations performed with PSIM software were able to validate the control system.The realization and testing of the photovoltaic system were achieved in the Photovoltaic laboratory of the Centre for Research and Energy Technologies at the Technopark Borj Cedria. Experimental results verify the effeciency of the proposed system.

Re-examination of sea lamprey control policies for the St. Marys River: Completion of an adaptive management cycle

USGS Publications Warehouse

Jones, Michael L.; Brenden, Travis O.; Irwin, Brian J.

2015-01-01

The St. Marys River (SMR) historically has been a major producer of sea lampreys (Petromyzon marinus) in the Laurentian Great Lakes. In the early 2000s, a decision analysis (DA) project was conducted to evaluate sea lamprey control policies for the SMR; this project suggested that an integrated policy of trapping, sterile male releases, and Bayluscide treatment was the most cost-effective policy. Further, it concluded that formal assessment of larval sea lamprey abundance and distribution in the SMR would be valuable for future evaluation of control strategies. We updated this earlier analysis, adding information from annual larval assessments conducted since 1999 and evaluating additional control policies. Bayluscide treatments continued to be critical for sea lamprey control, but high recruitment compensation minimized the effectiveness of trapping and sterile male release under current feasible ranges. Because Bayluscide control is costly, development of strategies to enhance trapping success remains a priority. This study illustrates benefits of an adaptive management cycle, wherein models inform decisions, are updated based on learning achieved from those decisions, and ultimately inform future decisions.

Predicting Future-Year Ozone Concentrations: Integrated Observational-Modeling Approach for Probabilistic Evaluation of the Efficacy of Emission Control strategies

EPA Science Inventory

Regional-scale air quality models are being used to demonstrate attainment of the ozone air quality standard. In current regulatory applications, a regional-scale air quality model is applied for a base year and a future year with reduced emissions using the same meteorological ...

Investigating the Use of an Enterotropic Newcastle Disease Virus as a Recombinant Vaccine Platform Targeting Poultry Enteric Viruses

USDA-ARS?s Scientific Manuscript database

Control strategies for poultry viral enteric disease must include vaccine platforms that have been specifically designed to improve flock performance, lessen disease severity, and reduce viral transmission. With the exception of certain autogenous vaccines, no vaccines currently exist to aid in the ...

Army Sustainability and Leadership in Energy and Environmental Design

DTIC Science & Technology

2010-08-01

penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE AUG 2010 2...strategies that DOD and the Army have implemented are policies such as buy-ing green products for cleaning and promoting tele- work or telecommuting

Measurement and Control Strategies for Sterol Glucosides to Improve Biodiesel Quality: Isolation and Characterization of Acylated Steryl Glucosides in Oilseed Crops of the Pacific Northwest

DOT National Transportation Integrated Search

2010-01-01

Acylated steryl glucosides (ASG), a form of phytosterols, have been identified in a variety of agricultural products, including the oilseeds of soybean and rapeseed. Currently, there are limited data available on the quality and quantity of phytoster...

NREL Fuels and Engines Research: Maximizing Vehicle Efficiency and

Science.gov Websites

Laboratory, we analyze the effects of fuel chemistry on ignition and the potential emissions impacts. Our lab research. It can be used to investigate fuel chemistry effects on current and near-term engine technology , independent control allows for deeper interrogation of fuel effects on future-generation engine strategies

Personalized Mailed Feedback for College Drinking Prevention: A Randomized Clinical Trial

ERIC Educational Resources Information Center

Larimer, Mary E.; Lee, Christine M.; Kilmer, Jason R.; Fabiano, Patricia M.; Stark, Christopher B.; Geisner, Irene M.; Mallett, Kimberly A.; Lostutter, Ty W.; Cronce, Jessica M.; Feeney, Maggie; Neighbors, Clayton

2007-01-01

The current study was designed to evaluate the efficacy of a mailed feedback and tips intervention as a universal prevention strategy for college drinking. Participants (N = 1,488) were randomly assigned to feedback or assessment-only control conditions. Results indicated that the mailed feedback intervention had a preventive effect on drinking…

IMPACT OF DECISION-MAKING STRATEGIES AND COMMUNICATION PROCESSES ON THE PUBLIC ACCEPTABILITY OF MUNICIPAL WASTE COMBUSTION RESIDUE UTILIZATION IN THE UNITED STATES

EPA Science Inventory

Of the identified current and proposed construction projects in which municipal solid waste combustion residues replace traditionally used materials, approximately half are located on landfills or other property controlled by project sponsors, one third are in publicly accessible...

Comparative transcriptomics of genetically divergent lines of chickens in response to Marek’s disease virus challenge at cytolytic phase

USDA-ARS?s Scientific Manuscript database

Marek’s disease (MD) remains an economically significant threat to poultry industry worldwide. Genetic resistance to MD is a promising alternative strategy to augment current control measures (vaccination and management). However, only a few functional genes reportedly conferring MD resistance have ...

Digital switched hydraulics

NASA Astrophysics Data System (ADS)

Pan, Min; Plummer, Andrew

2018-06-01

This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems (SIHSs). The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.

A Conceptual Framework for Examining School Finance Reform Options for the State of Ohio.

ERIC Educational Resources Information Center

Monk, David H.; Theobald, Neil D.

2001-01-01

Interviews involving 58 Ohio stakeholders focused on detailing state K-12 education goals, identifying the current system's strengths and weaknesses, and discussing the financial/political viability of potential school funding strategies. Consensus emerged regarding the role of property taxes, local control, the foundation formula rationale, and…

[Therapy concepts for diffuse peritonitis: When laparoscopic lavage and when open abdomen?].

PubMed

Güsgen, C; Schwab, R; Willms, A

2016-01-01

Secondary diffuse peritonitis still has a high morbidity and mortality even now; therefore, the various strategies and options for the different surgical therapies are undergoing an evidence-based review. Laparoscopic lavage without resection of the focus of sepsis for example is a profoundly different approach in the treatment of diffuse peritonitis from the damage control-based strategy of surgery with initial laparostomy and deferred anastomosis. The evidential data for minimally invasive therapy are comparatively well-reviewed for appendicitis, cholecystitis and ulcerated perforation of the stomach and duodenum. In contrast, the evidence for laparoscopy and minimally invasive surgery with lavage and deferred anastomosis or damage control in secondary peritonitis has improved but is still low and cannot yet be clearly recommended. This article presents an overview of the currently available therapeutic methods for diffuse peritonitis and a critical consideration of the evidence-based data. The key recommendation is that the decision to use a surgical procedure based on the currently available data depends more on the severity of the abdominal sepsis, the duration, the age of the patient and comorbidities than on the individual technique.

Future Automotive Aftertreatment Solutions: The 150°C Challenge Workshop Report

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

Zammit, Michael; DiMaggio, Craig L.; Kim, Chang H.

2013-10-15

With future fuel economy standards enacted, the U.S. automotive manufacturers (OEMs) are committed to pursuing a variety of high risk/highly efficient stoichiometric and lean combustion strategies to achieve superior performance. In recognition of this need, the U.S. Department of Energy (DOE) has partnered with domestic automotive manufacturers through U.S. DRIVE to develop these advanced technologies. However, before these advancements can be introduced into the U.S. market, they must also be able to meet increasingly stringent emissions requirements. A significant roadblock to this implementation is the inability of current catalyst and aftertreatment technologies to provide the required activity at the muchmore » lower exhaust temperatures that will accompany highly efficient combustion processes and powertrain strategies. Therefore, the goal of this workshop and report is to create a U.S. DRIVE emission control roadmap that will identify new materials and aftertreatment approaches that offer the potential for 90% conversion of emissions at low temperature (150°C) and are consistent with highly efficient combustion technologies currently under investigation within U.S. DRIVE Advanced Combustion and Emission Control (ACEC) programs.« less

A Review of PAT Strategies in Secondary Solid Oral Dosage Manufacturing of Small Molecules.

PubMed

Laske, Stephan; Paudel, Amrit; Scheibelhofer, Otto

2017-03-01

Pharmaceutical solid oral dosage product manufacturing is a well-established, yet revolutionizing area. To this end, process analytical technology (PAT) involves interdisciplinary and multivariate (chemical, physical, microbiological, and mathematical) methods for material (e.g., materials, intermediates, products) and process (e.g., temperature, pressure, throughput, etc.) analysis. This supports rational process modeling and enhanced control strategies for improved product quality and process efficiency. Therefore, it is often difficult to orient and find the relevant, integrated aspects of the current state-of-the-art. Especially, the link between fundamental research, in terms of sensor and control system development, to the application both in laboratory and manufacturing scale, is difficult to comprehend. This review compiles a nonexhaustive overview on current approaches from the recognized academia and industrial practices of PAT, including screening, selection, and final implementations in solid oral dosage manufacturing, through a wide diversity of use cases. Finally, the authors attempt to extract a common consensus toward developing PAT application guidance for different unit operations of drug product manufacturing. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Genetic variation in avocado stem weevils Copturus aguacatae (Coleoptera: Curculionidae) in Mexico.

PubMed

Engstrand, Rachel C; Cibrián Tovar, Juan; Cibrián-Jaramillo, Angélica; Kolokotronis, Sergios-Orestis

2010-12-01

The avocado stem weevil Copturus aguacatae is an important pest in avocado plantations. Its presence hinders the production and marketing of avocado in Mexico, the largest avocado producer worldwide. Biological control through pheromone synthesis, a strategy favored over chemical control in crops, is currently limited by difficult field identification of this species. Using DNA barcoding, we examine the patterns of genetic variation of C. aguacatae in avocado trees in Mexico to help facilitate its identification and biological control. We show that there is one single species of avocado stem weevil throughout the sampled sites in Mexico. Overall, haplotype diversity is high, with Oaxaca forming one distinct group and all other sampled populations are admixed irrespective of geographic origin. The results suggest that high gene flow is maintained in this species and that a global strategy for biocontrol can be designed and implemented throughout the sampled range.

Modeling of endoluminal and interstitial ultrasound hyperthermia and thermal ablation: applications to device design, feedback control, and treatment planning

PubMed Central

Prakash, Punit; Salgaonkar, Vasant A.; Diederich, Chris J.

2014-01-01

Endoluminal and catheter-based ultrasound applicators are currently under development and are in clinical use for minimally invasive hyperthermia and thermal ablation of various tissue targets. Computational models play a critical role in in device design and optimization, assessment of therapeutic feasibility and safety, devising treatment monitoring and feedback control strategies, and performing patient-specific treatment planning with this technology. The critical aspects of theoretical modeling, applied specifically to endoluminal and interstitial ultrasound thermotherapy, are reviewed. Principles and practical techniques for modeling acoustic energy deposition, bioheat transfer, thermal tissue damage, and dynamic changes in the physical and physiological state of tissue are reviewed. The integration of these models and applications of simulation techniques in identification of device design parameters, development of real time feedback-control platforms, assessing the quality and safety of treatment delivery strategies, and optimization of inverse treatment plans are presented. PMID:23738697

Added Value of Avian Influenza (H5) Day-Old Chick Vaccination for Disease Control in Egypt.

PubMed

Peyre, Marisa; Choisy, Marc; Sobhy, Heba; Kilany, Walid H; Gély, Marie; Tripodi, Astrid; Dauphin, Gwenaëlle; Saad, Mona; Roger, François; Lubroth, Juan; Jobre, Yilma

2016-05-01

The immunity profile against H5N1 highly pathogenic avian influenza (HPAI) in the commercial poultry value chain network in Egypt was modeled with the use of different vaccination scenarios. The model estimated the vaccination coverage, the protective seroconversion level, and the duration of immunity for each node of the network and vaccination scenario. Partial budget analysis was used to compare the benefit-cost of the different vaccination scenarios. The model predicted that targeting day-old chick avian influenza (AI) vaccination in industrial and large hatcheries would increase immunity levels in the overall poultry population in Egypt and especially in small commercial poultry farms (from <30% to >60%). This strategy was shown to be more efficient than the current strategy of using inactivated vaccines. Improving HPAI control in the commercial poultry sector in Egypt would have a positive impact to improve disease control.

Effective Coping With Supervisor Conflict Depends on Control: Implications for Work Strains.

PubMed

Eatough, Erin M; Chang, Chu-Hsiang

2018-01-11

This study examined the interactive effects of interpersonal conflict at work, coping strategy, and perceived control specific to the conflict on employee work strain using multisource and time-lagged data across two samples. In Sample 1, multisource data was collected from 438 employees as well as data from participant-identified secondary sources (e.g., significant others, best friends). In Sample 2, time-lagged data from 100 full-time employees was collected in a constructive replication. Overall, findings suggested that the success of coping efforts as indicated by lower strains hinges on the combination of the severity of the stressor, perceived control over the stressor, and coping strategy used (problem-focused vs. emotion-focused coping). Results from the current study provide insights for why previous efforts to document the moderating effects of coping have been inconsistent, especially with regards to emotion-focused coping. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Detection of Wolbachia in Aedes albopictus and Their Effects on Chikungunya Virus

PubMed Central

Ahmad, Noor Afizah; Vythilingam, Indra; Lim, Yvonne A. L.; Zabari, Nur Zatil Aqmar M.; Lee, Han Lim

2017-01-01

Wolbachia-based vector control strategies have been proposed as a means to augment the currently existing measures for controlling dengue and chikungunya vectors. Prior to utilizing Wolbachia as a novel vector control strategy, it is crucial to understand the Wolbachia–mosquito interactions. In this study, field surveys were conducted to screen for the infection status of Wolbachia in field-collected Aedes albopictus. The effects of Wolbachia in its native host toward the replication and dissemination of chikungunya virus (CHIKV) was also studied. The prevalence of Wolbachia-infected field-collected Ae. albopictus was estimated to be 98.6% (N = 142) for females and 95.1% (N = 102) for males in the population studied. The Ae. albopictus were naturally infected with both wAlbA and wAlbB strains. We also found that the native Wolbachia has no impact on CHIKV infection and minimal effect on CHIKV dissemination to secondary organs. PMID:27920393

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.

Competency‐based strategies for injury control and prevention curriculums in undergraduate medical education

PubMed Central

Phelan, Mary Beth; Falimirski, Mark E; Simpson, Deborah E; Czinner, Mary L; Hargarten, Stephen W

2007-01-01

Injury, including unintentional injury and intentional injury, is the leading cause of death in people aged ⩽44 years. Doctors often treat acute injuries, assist in the rehabilitation process and provide injury prevention guidance to patients. Current undergraduate medical school curriculums lack content and consistency in providing training in this area. A matrix to show the integration of injury control and prevention principles into existing undergraduate medical school curriculums is proposed. PMID:17296681

Older African American Homeless-Experienced Smokers' Attitudes Toward Tobacco Control Policies-Results from the HOPE HOME Study.

PubMed

Vijayaraghavan, Maya; Olsen, Pamela; Weeks, John; McKelvey, Karma; Ponath, Claudia; Kushel, Margot

2018-02-01

To examine attitudes toward tobacco control policies among older African American homeless-experienced smokers. A qualitative study. Oakland, California. Twenty-two African American older homeless-experienced smokers who were part of a longitudinal study on health and health-related outcomes (Health Outcomes of People Experiencing Homelessness in Older Middle Age Study). We conducted in-depth, semistructured interviews with each participant to explore beliefs and attitudes toward tobacco use and cessation, barriers to smoking cessation, and attitudes toward current tobacco control strategies including raising cigarette prices, smoke-free policies, and graphic warning labels. We used a grounded theory approach to analyze the transcripts. Community social norms supportive of cigarette smoking and co-use of tobacco with other illicit substances were strong motivators of initiation and maintenance of tobacco use. Self-reported barriers to cessation included nicotine dependence, the experience of being homeless, fatalistic attitudes toward smoking cessation, substance use, and exposure to tobacco industry marketing. While participants were cognizant of current tobacco control policies and interventions for cessation, they felt that they were not specific enough for African Americans experiencing homelessness. Participants expressed strong support for strategies that de-normalized tobacco use and advertised the harmful effects of tobacco. Older African American homeless-experienced smokers face significant barriers to smoking cessation. Interventions that advertise the harmful effects of tobacco may be effective in stimulating smoking cessation among this population.

A Dynamic Model for the Evaluation of Aircraft Engine Icing Detection and Control-Based Mitigation Strategies

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Rinehart, Aidan W.; Jones, Scott M.

2017-01-01

Aircraft flying in regions of high ice crystal concentrations are susceptible to the buildup of ice within the compression system of their gas turbine engines. This ice buildup can restrict engine airflow and cause an uncommanded loss of thrust, also known as engine rollback, which poses a potential safety hazard. The aviation community is conducting research to understand this phenomena, and to identify avoidance and mitigation strategies to address the concern. To support this research, a dynamic turbofan engine model has been created to enable the development and evaluation of engine icing detection and control-based mitigation strategies. This model captures the dynamic engine response due to high ice water ingestion and the buildup of ice blockage in the engines low pressure compressor. It includes a fuel control system allowing engine closed-loop control effects during engine icing events to be emulated. The model also includes bleed air valve and horsepower extraction actuators that, when modulated, change overall engine operating performance. This system-level model has been developed and compared against test data acquired from an aircraft turbofan engine undergoing engine icing studies in an altitude test facility and also against outputs from the manufacturers customer deck. This paper will describe the model and show results of its dynamic response under open-loop and closed-loop control operating scenarios in the presence of ice blockage buildup compared against engine test cell data. Planned follow-on use of the model for the development and evaluation of icing detection and control-based mitigation strategies will also be discussed. The intent is to combine the model and control mitigation logic with an engine icing risk calculation tool capable of predicting the risk of engine icing based on current operating conditions. Upon detection of an operating region of risk for engine icing events, the control mitigation logic will seek to change the engines operating point to a region of lower risk through the modulation of available control actuators while maintaining the desired engine thrust output. Follow-on work will assess the feasibility and effectiveness of such control-based mitigation strategies.

Dairy farmers' perceptions toward the implementation of on-farm Johne's disease prevention and control strategies.

PubMed

Ritter, C; Jansen, J; Roth, K; Kastelic, J P; Adams, C L; Barkema, H W

2016-11-01

Implementation of specific management strategies on dairy farms is currently the most effective way to reduce the prevalence of Johne's disease (JD), an infectious chronic enteritis of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). However, dairy farmers often fail to implement recommended strategies. The objective of this study was to assess perceptions of farmers participating in a JD prevention and control program toward recommended practices, and explore factors that influence whether or not a farmer adopts risk-reducing measures for MAP transmission. Semi-structured interviews were conducted with 25 dairy farmers enrolled in a voluntary JD control program in Alberta, Canada. Principles of classical grounded theory were used for participant selection, interviewing, and data analysis. Additionally, demographic data and MAP infection status were collected and analyzed using quantitative questionnaires and the JD control program database. Farmers' perceptions were distinguished according to 2 main categories: first, their belief in the importance of JD, and second, their belief in recommended JD prevention and control strategies. Based on these categories, farmers were classified into 4 groups: proactivists, disillusionists, deniers, and unconcerned. The first 2 groups believed in the importance of JD, and proactivists and unconcerned believed in proposed JD prevention and control measures. Groups that regarded JD as important had better knowledge about best strategies to reduce MAP transmission and had more JD risk assessments conducted on their farm. Although not quantified, it also appeared that these groups had more JD prevention and control practices in place. However, often JD was not perceived as a problem in the herd and generally farmers did not regard JD control as a "hot topic" in communications with their herd veterinarian and other farmers. Recommendations regarding how to communicate with farmers and motivate various groups of farmers according to their specific perceptions were provided to optimize adoption of JD prevention and control measures and thereby increase success of voluntary JD control programs. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Prevention and control of malaria in pregnancy - new threats, new opportunities?

PubMed

Rogerson, Stephen J; Unger, Holger W

2017-04-01

Over 100 million women and their babies are at risk of malaria in pregnancy each year. Malaria prevention in pregnancy relies on long-lasting insecticidal nets (LLINs), and, in Africa, intermittent preventive treatment in pregnancy (IPTp). Increasing resistance of malaria parasites to sulfadoxine-pyrimethamine, the only drug endorsed for IPTp, and increasing mosquito resistance to pyrethroids used in LLINs, threaten the efficacy of these proven strategies, while operational challenges restrict their implementation in areas of great need. Areas Covered: This review summarizes strategies for malaria prevention in pregnancy (both currently used and those undergoing preclinical and clinical evaluation), primarily drawing on publications and study protocols from the last decade. Challenges associated with each strategy are discussed, including the particular problem of HIV and malaria in pregnancy, and areas of further research are highlighted. Expert Commentary: Alternative drugs for IPTp are needed. Dihydroartemisinin-piperaquine is particularly promising, but requires further evaluation, and might contribute to artemisinin resistance. Intermittent screening and treatment in pregnancy (ISTp) is an alternative to IPTp that could reduce unnecessary antenatal drug exposure and resistance risk, but it is not recommended with current, insensitive screening tests. Optimal strategies for areas of low or declining malaria transmission remain to be determined.

Children with social anxiety and other anxiety disorders show similar deficits in habitual emotional regulation: evidence for a transdiagnostic phenomenon.

PubMed

Keil, Verena; Asbrand, Julia; Tuschen-Caffier, Brunna; Schmitz, Julian

2017-07-01

Deficits in emotion regulation (ER) are an important factor in maintaining social anxiety disorder (SAD) in adults. As SAD and ER problems typically develop during childhood and adolescence, and are maintained dynamically within the parent-child dyad, research on families can help to reveal the role ER plays in the early development of SAD. The current study assessed self-reported habitual ER in dyads of children with SAD (n = 31), children with mixed anxiety disorders (MAD; n = 41) and healthy control children (HC; n = 36), and their parents. Results indicate a transdiagnostic quality of ER in that, children with SAD and children with MAD similarly reported less adaptive and more maladaptive ER strategies than HC children, whereas no group differences in parental ER strategies emerged. Furthermore, children's ER strategies aggressive action, withdrawal and self-devaluation and the parental ER strategy reappraisal were associated with social anxiety symptoms. These results suggest that there may be deficits in ER which generalize across childhood anxiety disorders. Our results are discussed in relation to current theories and their implications for treatment of childhood SAD.

LED luminaire longevity strategy models comparison

NASA Astrophysics Data System (ADS)

Lemieux, Hugo; Thibault, Simon; Martel, Alain A.

2010-08-01

As energy efficiency becomes more and more important, light-emitting diodes (LEDs) are a promising alternative to traditional lighting. Indeed, the energy efficiency of LEDs is still improving as their luminosity is modulated by current. Moreover, for applications such as exterior lamp posts, their small size, directionality, colors and high frequency response allow to combine them and provide design possibilities which are impossible with any other light source. However, as any lamp, LEDs have a lumen depreciation which is a function of both current and temperature. Thus, to take advantage of the full characteristics of LEDs, LED luminaire longevity strategies must be carefully studied and planned, especially since the IES and CIE guidelines state clearly that the luminaire must maintain the rated recommended light level until the end of the system's operating life. The recommended approach for LED luminaire specification is therefore to use the end-of-life light level when evaluating the luminaire. Different power supply strategies have been simulated to determine which one maximizes energy saving and lifetime. With these results, it appears that active control can save at least 25% in energy, but the best strategy cannot be determined because of uncertainties in luminosity degradation models.

Challenges in reducing dengue burden; diagnostics, control measures and vaccines.

PubMed

Lam, Sai Kit

2013-09-01

Dengue is a major public health concern worldwide, with the number of infections increasing globally. The illness imposes the greatest economic and human burden on developing countries that have limited resources to deal with the scale of the problem. No cure for dengue exists; treatment is limited to rehydration therapy, and with vector control strategies proving to be relatively ineffective, a vaccine is an urgent priority. Despite the numerous challenges encountered in the development of a dengue vaccine, several vaccine candidates have shown promise in clinical development and it is believed that a vaccination program would be at least as cost-effective as current vector control programs. The lead candidate vaccine is a tetravalent, live attenuated, recombinant vaccine, which is currently in Phase III clinical trials. Vaccine introduction is a complex process that requires consideration and is discussed here. This review discusses the epidemiology, burden and pathogenesis of dengue, as well as the vaccine candidates currently in clinical development.

"Alert-Audit-Act": assessment of surveillance and response strategy for malaria elimination in three low-endemic settings of Myanmar in 2016.

PubMed

Kyaw, Aye Mon Mon; Kathirvel, Soundappan; Das, Mrinalini; Thapa, Badri; Linn, Nay Yi Yi; Maung, Thae Maung; Lin, Zaw; Thi, Aung

2018-01-01

Myanmar, a malaria endemic country of Southeast Asia, adopted surveillance and response strategy similar to "1-3-7" Chinese strategy to achieve sub-national elimination in six low-endemic region/states of the country. Among these, Yangon, Bago-East, and Mon region/states have implemented this malaria surveillance and response strategy with modification in 2016. The current study was conducted to assess the case notification, investigation, classification, and response strategy (NICR) in these three states. This was a retrospective cohort study using routine program data of all patients with malaria diagnosed and reported under the National Malaria Control Programme in 2016 from the above three states. As per the program, all malaria cases need to be notified within 1 day and investigated within 3 days of diagnosis and response to control (active case detection and control) should be taken for all indigenous malaria cases within 7 days of diagnosis. A total of 959 malaria cases were diagnosed from the study area in 2016. Of these, the case NICR details were available only for 312 (32.5%) malaria cases. Of 312 cases, the case notification, investigation, and classification were carried out within 3 days of malaria diagnosis in 95.5% cases (298/312). Of 208 indigenous malaria cases (66.7%, 208/312), response to control was taken in 96.6% (201/208) within 7 days of diagnosis. The timeline at each stage of the strategy namely case notification, investigation, classification, and response to control was followed, and response action was taken in nearly all indigenous malaria cases for the available case information. Strengthening of health information and monitoring system is needed to avoid missing information. Future research on feasibility of mobile/tablet-based surveillance system and providing response to all cases including imported malaria can be further studied.

Comparison of Irradiation and Wolbachia Based Approaches for Sterile-Male Strategies Targeting Aedes albopictus

PubMed Central

Atyame, Célestine M.; Labbé, Pierrick; Lebon, Cyrille; Weill, Mylène; Moretti, Riccardo; Marini, Francesca; Gouagna, Louis Clément; Calvitti, Maurizio; Tortosa, Pablo

2016-01-01

The global expansion of Aedes albopictus together with the absence of vaccines for most of the arboviruses transmitted by this mosquito has stimulated the development of sterile-male strategies aiming at controlling disease transmission through the suppression of natural vector populations. In this context, two environmentally friendly control strategies, namely the Sterile Insect Technique (SIT) and the Wolbachia-based Incompatible Insect Technique (IIT) are currently being developed in several laboratories worldwide. So far however, there is a lack of comparative assessment of these strategies under the same controlled conditions. Here, we compared the mating capacities, i.e. insemination capacity, sterilization capacity and mating competitiveness of irradiated (35 Gy) and incompatible Ae. albopictus males at different ages and ratios under laboratory controlled conditions. Our data show that there was no significant difference in insemination capacity of irradiated and incompatible males, both male types showing lower capacities than untreated males at 1 day but recovering full capacity within 5 days following emergence. Regarding mating competitiveness trials, a global observed trend is that incompatible males tend to induce a lower hatching rate than irradiated males in cage controlled confrontations. More specifically, incompatible males were found more competitive than irradiated males in 5:1 ratio regardless of age, while irradiated males were only found more competitive than incompatible males in the 1:1 ratio at 10 days old. Overall, under the tested conditions, IIT seemed to be slightly more effective than SIT. However, considering that a single strategy will likely not be adapted to all environments, our data stimulates the need for comparative assessments of distinct strategies in up-scaled conditions in order to identify the most suitable and safe sterilizing technology to be implemented in a specific environmental setting and to identify the parameters requiring fine tuning in order to reach optimal release conditions. PMID:26765951

Three-phase multilevel solar inverter for motor drive system

NASA Astrophysics Data System (ADS)

Bhasagare, Mayuresh P.

This thesis deals with three phase inverters and the different control strategies that can be associated with an inverter being used together. The first part of this thesis discusses the present research in the fields of PV panels, motor drive systems and three phase inverters along with their control. This control includes various strategies like MPPT, Volts-Hertz and modulation index compensation. Incorporating these techniques together is the goal of this thesis. A new topology for operating an open end motor drive system has also been discusses, where a boost converter and a flyback converter have been used in cascade to run a three phase motor. The main advantage of this is increasing the number of levels and improving the quality of the output voltage, not to mention a few other benefits of having the proposed circuit. A new algorithm has also been designed for starting and stopping the motor, which controls the current drawn from the power source during starting.

Insight into Alternative Approaches for Control of Avian Influenza in Poultry, with Emphasis on Highly Pathogenic H5N1

PubMed Central

Abdelwhab, E. M.; Hafez, Hafez M.

2012-01-01

Highly pathogenic avian influenza virus (HPAIV) of subtype H5N1 causes a devastating disease in poultry but when it accidentally infects humans it can cause death. Therefore, decrease the incidence of H5N1 in humans needs to focus on prevention and control of poultry infections. Conventional control strategies in poultry based on surveillance, stamping out, movement restriction and enforcement of biosecurity measures did not prevent the virus spreading, particularly in developing countries. Several challenges limit efficiency of the vaccines to prevent outbreaks of HPAIV H5N1 in endemic countries. Alternative and complementary approaches to reduce the current burden of H5N1 epidemics in poultry should be encouraged. The use of antiviral chemotherapy and natural compounds, avian-cytokines, RNA interference, genetic breeding and/or development of transgenic poultry warrant further evaluation as integrated intervention strategies for control of HPAIV H5N1 in poultry. PMID:23202521

[Epidemic situation and prevention and control strategy of clonorchiasis in Guangdong Province, China].

PubMed

Zhuo-Hui, Deng; Yue-Yi, Fang

2016-05-24

Clonorchiasis is one of the food-borne parasitic diseases. Adult parasites live in the human liver and gallbladder tube system, causing serious complications, such as gallstones, cholecystitis and cholangitis, and even bile duct cancer. The disease is very popular in our country, and the population infection rate is high. It is an important public health problem. Guangdong Province is the earliest province being found of clonorchiasis and with serious epidemic. In the second national human parasitic diseases distribution survey, the results showed that the average infection rate of Clonorchis sinensis in the epidemic areas in Guangdong was 16.42%. It is estimated that the population of C. sinensis infection is over 6 million. The prevention and control of clonorchiasis in China is still in the initial stage currently and we face many challenges such as unclear epidemic characteristics and transmission mode, and lack of long-term prevention and control mechanism. This article introduces the epidemic situation of clonorchiasis and prevention and control strategies and measures in Guangdong.

A Research Agenda to Underpin Malaria Eradication

PubMed Central

Alonso, Pedro L.; Brown, Graham; Arevalo-Herrera, Myriam; Binka, Fred; Chitnis, Chetan; Collins, Frank; Doumbo, Ogobara K.; Greenwood, Brian; Hall, B. Fenton; Levine, Myron M.; Mendis, Kamini; Newman, Robert D.; Plowe, Christopher V.; Rodríguez, Mario Henry; Sinden, Robert; Slutsker, Laurence; Tanner, Marcel

2011-01-01

The interruption of malaria transmission worldwide is one of the greatest challenges for international health and development communities. The current expert view suggests that, by aggressively scaling up control with currently available tools and strategies, much greater gains could be achieved against malaria, including elimination from a number of countries and regions; however, even with maximal effort we will fall short of global eradication. The Malaria Eradication Research Agenda (malERA) complements the current research agenda—primarily directed towards reducing morbidity and mortality—with one that aims to identify key knowledge gaps and define the strategies and tools that will result in reducing the basic reproduction rate to less than 1, with the ultimate aim of eradication of the parasite from the human population. Sustained commitment from local communities, civil society, policy leaders, and the scientific community, together with a massive effort to build a strong base of researchers from the endemic areas will be critical factors in the success of this new agenda. PMID:21311579

Back Disorder Intervention Strategies for Mass Transit Operators Exposed to Whole-Body VIBRATION—COMPARISON of Two Transit System Approaches and Practices

NASA Astrophysics Data System (ADS)

Johanning, E.

1998-08-01

Occupational long-term whole-body vibration (WBV) has been recognized as a major risk factor for low back disorders, one of the most important reasons for medical impairment and early permanent disability among mass transit operators. Although no firm health and safety vibration exposure threshold limits have been established, the available data suggests that rail vehicle operators would probably fall under the proposed WBV “action levels” of the EU directive provisions for protection from physical hazards. This provision calls for technical, administrative and medical controls. This paper examines and compares the current conditions, provisions and plans of two major mass transit systems, the New Yorker MTA and the Munich MVV. The available data, information and publications (English/German) on working conditions, vibration exposure, epidemiology and intervention strategies (primary and secondary prevention) for rail bound mass transit workers were reviewed. Results strongly suggest that the MTA transit system has currently and in the near future no effective and meaningful controls in place to significantly reduce the WBV exposure of subway operators. It appears that the MVV system has more and better control measures in place to reduce harmful effects of WBV. Results of a scientific evaluation of a participatory, collaborative project in the MVV system suggest that the MVV may have developed a successful method of a “condition prevention” (Verhältnisprävention)—and “behavioral prevention” (Verhaltensprävention) intervention strategy, which appears beneficial for WBV exposed workers with existing low back pain. Long-term outcomes and benefits need to be assessed further.

Canadian Headache Society guideline for migraine prophylaxis.

PubMed

Pringsheim, Tamara; Davenport, W Jeptha; Mackie, Gordon; Worthington, Irene; Aubé, Michel; Christie, Suzanne N; Gladstone, Jonathan; Becker, Werner J

2012-03-01

The primary objective of this guideline is to assist the practitioner in choosing an appropriate prophylactic medication for an individual with migraine, based on current evidence in the medical literature and expert consensus. This guideline is focused on patients with episodic migraine (headache on ≤ 14 days a month). Through a comprehensive search strategy, randomized, double blind, controlled trials of drug treatments for migraine prophylaxis and relevant Cochrane reviews were identified. Studies were graded according to criteria developed by the US Preventive Services Task Force. Recommendations were graded according to the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group. In addition, a general literature review and expert consensus were used for aspects of prophylactic therapy for which randomized controlled trials are not available. Prophylactic drug choice should be based on evidence for efficacy, side-effect profile, migraine clinical features, and co-existing disorders. Based on our review, 11 prophylactic drugs received a strong recommendation for use (topiramate, propranolol, nadolol, metoprolol, amitriptyline, gabapentin, candesartan, butterbur, riboflavin, coenzyme Q10, and magnesium citrate) and 6 received a weak recommendation (divalproex sodium, flunarizine, pizotifen, venlafaxine, verapamil, and lisinopril). Quality of evidence for different medications varied from high to low. Prophylactic treatment strategies were developed to assist the practitioner in selecting a prophylactic drug for specific clinical situations. These strategies included: first time strategies for patients who have not had prophylaxis before (a beta-blocker and a tricyclic strategy), low side effect strategies (including both drug and herbal/vitamin/mineral strategies), a strategy for patients with high body mass index, strategies for patients with co-existent hypertension or with co-existent depression and /or anxiety, and additional monotherapy drug strategies for patients who have failed previous prophylactic trials. Further strategies included a refractory migraine strategy and strategies for prophylaxis during pregnancy and lactation. There is good evidence from randomized controlled trials for use of a number of different prophylactic medications in patients with migraine. Medication choice for an individual patient requires careful consideration of patient clinical features.

Soft regulations in pharmaceutical policy making: an overview of current approaches and their consequences.

PubMed

Wettermark, Björn; Godman, Brian; Jacobsson, Bengt; Haaijer-Ruskamp, Flora M

2009-01-01

It is a challenge to improve public health within limited resources. Pharmaceutical policy making is a greater challenge due to conflicting interests between key stakeholder groups. This paper reviews current and future strategies to help improve the quality and efficiency of care, with special emphasis on demand-side controls for pharmaceutical prescribing. A large number of different educational, organizational, financial and regulatory strategies have been applied in pharmaceutical policy making. However, the effectiveness of most strategies has not been thoroughly evaluated and there is evidence that the behaviour of healthcare professionals is difficult to influence with traditional methods. During the last decades, new modes of governing and new governing constellations have also appeared in healthcare. However, relationships between those who regulate and those regulated are often unclear. New approaches have recently been introduced, including extensive dissemination strategies for guidelines and extensive quality assessment programmes where physicians' performances are measured against agreed standards or against each other. The main components of these 'soft regulations' are standardization, monitoring and agenda setting. However, the impact of these new modes on health provision and overall costs is often unknown, and the increased focus on monitoring may result in a higher conformity and uniformity that may not always benefit all key stakeholders. Alongside this, a substantial growth of auditing associations controlling a diminishing minority of people actually performing the tasks may be costly and counter-productive. As a result, new effective strategies are urgently needed to help maintain comprehensive healthcare without prohibitively raising taxes or insurance premiums. This is especially important where countries are faced with extreme financial problems. Healthcare researchers may benefit from researching other areas of society. However, any potential strategies initiated must be adequately researched, debated and evaluated to enhance implementation. We hope this opinion paper is the first step in the process to develop and implement new demand-side initiatives building on existing 'soft regulations'.

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

Silva, E.R.C. da; Filho, B.J.C.

This paper presents a PWM current clamping circuit for improving a series resonant DC link converter. This circuit is capable of reducing current peaks to about 1.2--1.4 times the DC bias current. When desired, resonant transition creates notches in the dc link current, allowing the converter`s switches to synchronize with external PWM strategy. A regulated DC current source may be obtained--by using a conventional rectifier source--to feed a DC load or a current source inverter. Phase plane approach makes ease the understanding the operation, control and design procedure of the circuit. Another topology is derived and its features compared tomore » the first circuit. Simulation results for the simplified circuit and for a three-phase induction motor driven by such inverter will be presented. Moreover, the principle is corroborated by experimental results.« less

Steam generator degradation: Current mitigation strategies for controlling corrosion

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

Millett, P.

1997-02-01

Steam Generator degradation has caused substantial losses of power generation, resulted in large repair and maintenance costs, and contributed to significant personnel radiation exposures in Pressurized Water Reactors (PWRs) operating throughout the world. EPRI has just published the revised Steam Generator Reference Book, which reviews all of the major forms of SG degradation. This paper discusses the types of SG degradation that have been experienced with emphasis on the mitigation strategies that have been developed and implemented in the field. SG degradation is presented from a world wide perspective as all countries operating PWRs have been effected to one degreemore » or another. The paper is written from a US. perspective where the utility industry is currently undergoing tremendous change as a result of deregulation of the electricity marketplace. Competitive pressures are causing utilities to strive to reduce Operations and Maintenance (O&M) and capital costs. SG corrosion is a major contributor to the O&M costs of PWR plants, and therefore US utilities are evaluating and implementing the most cost effective solutions to their corrosion problems. Mitigation strategies developed over the past few years reflect a trend towards plant specific solutions to SG corrosion problems. Since SG degradation is in most cases an economic problem and not a safety problem, utilities can focus their mitigation strategies on their unique financial situation. Accordingly, the focus of R&D has shifted from the development of more expensive, prescriptive solutions (e.g. reduced impurity limits) to corrosion problems to providing the utilities with a number of cost effective mitigation options (e.g. molar ratio control, boric acid treatment).« less

Strategies for Radiation Hardness Testing of Power Semiconductor Devices

NASA Technical Reports Server (NTRS)

Soltis, James V. (Technical Monitor); Patton, Martin O.; Harris, Richard D.; Rohal, Robert G.; Blue, Thomas E.; Kauffman, Andrew C.; Frasca, Albert J.

2005-01-01

Plans on the drawing board for future space missions call for much larger power systems than have been flown in the past. These systems would employ much higher voltages and currents to enable more powerful electric propulsion engines and other improvements on what will also be much larger spacecraft. Long term human outposts on the moon and planets would also require high voltage, high current and long life power sources. Only hundreds of watts are produced and controlled on a typical robotic exploration spacecraft today. Megawatt systems are required for tomorrow. Semiconductor devices used to control and convert electrical energy in large space power systems will be exposed to electromagnetic and particle radiation of many types, depending on the trajectory and duration of the mission and on the power source. It is necessary to understand the often very different effects of the radiations on the control and conversion systems. Power semiconductor test strategies that we have developed and employed will be presented, along with selected results. The early results that we have obtained in testing large power semiconductor devices give a good indication of the degradation in electrical performance that can be expected in response to a given dose. We are also able to highlight differences in radiation hardness that may be device or material specific.

Predictive Management of Asian Carps in the Upper Mississippi River System

USGS Publications Warehouse

Vondracek, Bruce C.; Carlson, Andrew K.

2014-01-01

Prolific non-native organisms pose serious threats to ecosystems and economies worldwide. Nonnative bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix), collectively referred to as Asian carps, continue to colonize aquatic ecosystems throughout the central United States. These species are r-selected, exhibiting iteroparous spawning, rapid growth, broad environmental tolerance, high density, and long-distance movement. Hydrological, thermal, and physicochemical conditions are favorable for establishment beyond the current range, rendering containment and control imperative. Ecological approaches to confine Asian carp populations and prevent colonization characterize contemporary management in the United States. Foraging and reproduction of Asian carps govern habitat selection and movement, providing valuable insight for predictive control. Current management approaches are progressive and often anticipatory but deficient in human dimensions. We define predictive management of Asian carps as synthesis of ecology and human dimensions at regional and local scales to develop strategies for containment and control. We illustrate predictive management in the Upper Mississippi River System and suggest resource managers integrate predictive models, containment paradigms, and human dimensions to design effective, socially acceptable management strategies. Through continued research, university-agency collaboration, and public engagement, predictive management of Asian carps is an auspicious paradigm for preventing and alleviating consequences of colonization in the United States.

Antimicrobial efficacy of a novel eucalyptus oil, chlorhexidine digluconate and isopropyl alcohol biocide formulation.

PubMed

Hendry, Emma; Conway, Barbara; Worthington, Tony

2012-10-30

Effective surface disinfection is a fundamental infection control strategy within healthcare. This study assessed the antimicrobial efficacy of novel biocide formulations comprising 5% and 2% eucalyptus oil (EO) combined with 2% chlorhexidine digluconate (CHG) and 70% isopropyl alcohol (IPA) contained within a wipe. The efficacy of this novel antimicrobial formulation to remove and eliminate methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and Candida albicans from steel surfaces was investigated. Adpression studies of pre-contaminated wipes were also utilised to assess their potential to induce cross-contamination between hard surfaces. Furthermore, the bactericidal nature of the EO-formulation was established in addition to time-kill. The EO-containing formulations demonstrated bactericidal antimicrobial efficacy against all microorganisms and did not induce surface cross-contamination. There was no significant difference (p < 0.05) between the 5% and 2% EO formulations in their ability to remove microorganisms from steel surfaces, however both significantly (p < 0.05) removed more than the control formulations. Microbial biofilms were eliminated within 10 min (p < 0.05) when exposed to the EO formulations. Our novel EO-formulation demonstrated rapid antimicrobial efficacy for potential disinfection and elimination of microbial biofilms from hard surfaces and may therefore be a useful adjunct to current infection control strategies currently employed within healthcare facilities.

Antimicrobial Efficacy of a Novel Eucalyptus Oil, Chlorhexidine Digluconate and Isopropyl Alcohol Biocide Formulation

PubMed Central

Hendry, Emma; Conway, Barbara; Worthington, Tony

2012-01-01

Effective surface disinfection is a fundamental infection control strategy within healthcare. This study assessed the antimicrobial efficacy of novel biocide formulations comprising 5% and 2% eucalyptus oil (EO) combined with 2% chlorhexidine digluconate (CHG) and 70% isopropyl alcohol (IPA) contained within a wipe. The efficacy of this novel antimicrobial formulation to remove and eliminate methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli and Candida albicans from steel surfaces was investigated. Adpression studies of pre-contaminated wipes were also utilised to assess their potential to induce cross-contamination between hard surfaces. Furthermore, the bactericidal nature of the EO-formulation was established in addition to time-kill. The EO-containing formulations demonstrated bactericidal antimicrobial efficacy against all microorganisms and did not induce surface cross-contamination. There was no significant difference (p < 0.05) between the 5% and 2% EO formulations in their ability to remove microorganisms from steel surfaces, however both significantly (p < 0.05) removed more than the control formulations. Microbial biofilms were eliminated within 10 min (p < 0.05) when exposed to the EO formulations. Our novel EO-formulation demonstrated rapid antimicrobial efficacy for potential disinfection and elimination of microbial biofilms from hard surfaces and may therefore be a useful adjunct to current infection control strategies currently employed within healthcare facilities. PMID:23203047

Projecting the Long-Term Impact of School- or Community-Based Mass-Treatment Interventions for Control of Schistosoma Infection

PubMed Central

Wang, Xiaoxia; Gurarie, David; Mungai, Peter L.; Muchiri, Eric M.; Kitron, Uriel; King, Charles H.

2012-01-01

Background Schistosomiasis remains a significant health burden in many areas of the world. Morbidity control, focused on limiting infection intensity through periodic delivery of anti-schistosomal medicines, is the thrust of current World Health Organization guidelines (2006) for reduction of Schistosoma-related disease. A new appreciation of the lifetime impact of repeated Schistosoma infection has directed attention toward strategies for greater suppression of parasite infection per se, with the goal of transmission interruption. Variations in drug schedules involving increased population coverage and/or treatment frequency are now undergoing field trials. However, their relative effectiveness in long-term infection suppression is presently unknown. Methodology/Principal Findings Our study used available field data to calibrate advanced network models of village-level Schistosoma transmission to project outcomes of six different community- or school age-based programs, as compared to the impact of current 2006 W.H.O. recommended control strategies. We then scored the number of years each of 10 typical villages would remain below 10% infection prevalence (a practicable level associated with minimal prevalence of disease). All strategies that included four annual treatments effectively reduced community prevalence to less than 10%, while programs having yearly gaps (‘holidays’) failed to reach this objective in half of the communities. Effective post-program suppression of infection prevalence persisted in half of the 10 villages for 7–10 years, whereas in five high-risk villages, program effects on prevalence lasted zero to four years only. Conclusions/Significance At typical levels of treatment adherence (60 to 70%), current WHO recommendations will likely not achieve effective suppression of Schistosoma prevalence unless implemented for ≥6 years. Following more aggressive 4 year annual intervention, some communities may be able to continue without further intervention for 8–10 years, while in higher-risk communities, annual treatment may prove necessary until eco-social factors fostering transmission are removed. Effective ongoing surveillance and locally targeted annual intervention must then become their mainstays of control. PMID:23166850

Near-Nash targeting strategies for heterogeneous teams of autonomous combat vehicles

NASA Astrophysics Data System (ADS)

Galati, David G.; Simaan, Marwan A.

2008-04-01

Military strategists are currently seeking methodologies to control large numbers of autonomous assets. Automated planners based upon the Nash equilibrium concept in non-zero sum games are one option. Because such planners inherently consider possible adversarial actions, assets are able to adapt to, and to some extent predict, potential enemy actions. However, these planners must function properly both in cases in which a pure Nash strategy does not exist and in scenarios possessing multiple Nash equilibria. Another issue that needs to be overcome is the scalability of the Nash equilibrium. That is, as the dimensionality of the problem increases, the Nash strategies become unfeasible to compute using traditional methodologies. In this paper we introduce the concept of near-Nash strategies as a mechanism to overcome these difficulties. We then illustrate this concept by deriving the near-Nash strategies and using these strategies as the basis for an intelligent battle plan for heterogeneous teams of autonomous combat air vehicles in the Multi-Team Dynamic Weapon Target Assignment model.

Multidimensional optimal droop control for wind resources in DC microgrids

NASA Astrophysics Data System (ADS)

Bunker, Kaitlyn J.

Two important and upcoming technologies, microgrids and electricity generation from wind resources, are increasingly being combined. Various control strategies can be implemented, and droop control provides a simple option without requiring communication between microgrid components. Eliminating the single source of potential failure around the communication system is especially important in remote, islanded microgrids, which are considered in this work. However, traditional droop control does not allow the microgrid to utilize much of the power available from the wind. This dissertation presents a novel droop control strategy, which implements a droop surface in higher dimension than the traditional strategy. The droop control relationship then depends on two variables: the dc microgrid bus voltage, and the wind speed at the current time. An approach for optimizing this droop control surface in order to meet a given objective, for example utilizing all of the power available from a wind resource, is proposed and demonstrated. Various cases are used to test the proposed optimal high dimension droop control method, and demonstrate its function. First, the use of linear multidimensional droop control without optimization is demonstrated through simulation. Next, an optimal high dimension droop control surface is implemented with a simple dc microgrid containing two sources and one load. Various cases for changing load and wind speed are investigated using simulation and hardware-in-the-loop techniques. Optimal multidimensional droop control is demonstrated with a wind resource in a full dc microgrid example, containing an energy storage device as well as multiple sources and loads. Finally, the optimal high dimension droop control method is applied with a solar resource, and using a load model developed for a military patrol base application. The operation of the proposed control is again investigated using simulation and hardware-in-the-loop techniques.

Portable inference engine: An extended CLIPS for real-time production systems

NASA Technical Reports Server (NTRS)

Le, Thach; Homeier, Peter

1988-01-01

The present C-Language Integrated Production System (CLIPS) architecture has not been optimized to deal with the constraints of real-time production systems. Matching in CLIPS is based on the Rete Net algorithm, whose assumption of working memory stability might fail to be satisfied in a system subject to real-time dataflow. Further, the CLIPS forward-chaining control mechanism with a predefined conflict resultion strategy may not effectively focus the system's attention on situation-dependent current priorties, or appropriately address different kinds of knowledge which might appear in a given application. Portable Inference Engine (PIE) is a production system architecture based on CLIPS which attempts to create a more general tool while addressing the problems of real-time expert systems. Features of the PIE design include a modular knowledge base, a modified Rete Net algorithm, a bi-directional control strategy, and multiple user-defined conflict resolution strategies. Problems associated with real-time applications are analyzed and an explanation is given for how the PIE architecture addresses these problems.

Effects of a chirped bias voltage on ion energy distributions in inductively coupled plasma reactors

NASA Astrophysics Data System (ADS)

Lanham, Steven J.; Kushner, Mark J.

2017-08-01

The metrics for controlling reactive fluxes to wafers for microelectronics processing are becoming more stringent as feature sizes continue to shrink. Recent strategies for controlling ion energy distributions to the wafer involve using several different frequencies and/or pulsed powers. Although effective, these strategies are often costly or present challenges in impedance matching. With the advent of matching schemes for wide band amplifiers, other strategies to customize ion energy distributions become available. In this paper, we discuss results from a computational investigation of biasing substrates using chirped frequencies in high density, electronegative inductively coupled plasmas. Depending on the frequency range and chirp duration, the resulting ion energy distributions exhibit components sampled from the entire frequency range. However, the chirping process also produces transient shifts in the self-generated dc bias due to the reapportionment of displacement and conduction with frequency to balance the current in the system. The dynamics of the dc bias can also be leveraged towards customizing ion energy distributions.

Can prevention eliminate caries?

PubMed

O'Mullane, D

1995-07-01

There are four main factors involved in the carious process: at-risk tooth structure, plaque flora, fermentable carbohydrates, and time. Based on our knowledge of the carious process, four main preventive strategies have been developed over the years, namely, fluorides, fissure sealing, dietary choice, and plaque control. Fluorides are having a major impact on smooth-surface caries; hence, strategies combining fluorides and fissure sealing are very effective. However, use of fissure sealing is still problematic. Changing dietary practices with a view to reducing dental caries seems to be having little impact on a global scale. Plaque control, as practiced routinely by the majority of people, is not sufficient to result in caries reductions. Deprivation and poverty are strongly associated with high caries levels. Although the preventive strategies currently available are likely to result in lower caries levels for many, for logistical reasons and because of factors associated with deprivation and poverty, caries is likely to remain a major public health problem in most communities for the foreseeable future.

Phytoremediation of ionic and methylmercury pollution

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

Meagher, Richard B.

2002-06-01

Our long-term objective is to enable highly productive plant species to extract, resist, detoxify, and/or sequester toxic organic and heavy metal pollutants (Meagher, 2000) applying scientific strategies and technologies from a rapidly developing field called phytoremediation. The phytoremediation of toxic elemental and organic pollutants requires the use relatively different approaches (Meagher, 2000). Our current specific objectives are to use transgenic plants to control the chemical species, electrochemical state, and aboveground binding of mercury to (a) prevent methylmercury from entering the food-chain, (b) remove mercury from polluted sites, and (c) hyperaccumulate mercury in aboveground tissues for later harvest. Various parts ofmore » this strategy are being critically tested by examining different genes in model plants and field species and comparing the results to control plants as we recently reviewed (Meagher et al., 2000; Rugh et al., 2000). A positive spin-off from this work on mercury has been a strategy for the phytoremediation of arsenic (Dhankher et al., 2002) and cadmium.« less

Phytoremediation of Ionic and Methyl Mercury Pollution

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

Meagher, Richard B.

Our long-term objective is to enable highly productive plant species to extract, resist, detoxify, and/or sequester toxic organic and heavy metal pollutants by applying scientific strategies and technologies from a rapidly developing field called phytoremediation. The phytoremediation of toxic elemental and organic pollutants employs a variety of different approaches (Meagher, 2000). Our current specific objectives are to use transgenic plants to control the chemical species, electrochemical state, transport, and aboveground binding of mercury to (a) prevent methylmercury from entering the food-chain, (b) remove mercury from polluted sites, and (c) hyperaccumulate mercury in aboveground tissues for later harvest and waste disposal.more » Various parts of this strategy are being critically tested by examining different genes in model plants and field species and comparing the results to control plants, as we reviewed previously (Meagher et al., 2000; Rugh et al., 2000). A positive spin-off from this work on mercury has been a strategy for the phytoremediation of arsenic (Dhankher et al., 2002) and cadmium (Dhankher et al., 2003).« less

Phytoremediation of ionic and methylmercury pollution

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

Meagher, Richard B.

Our long-term objective is to enable highly productive plant species to extract, resist, detoxify, and/or sequester toxic organic and heavy metal pollutants (Meagher, 2000) applying scientific strategies and technologies from a rapidly developing field called phytoremediation. The phytoremediation of toxic elemental and organic pollutants requires the use relatively different approaches (Meagher, 2000). Our current specific objectives are to use transgenic plants to control the chemical species, electrochemical state, and aboveground binding of mercury to (a) prevent methylmercury from entering the food-chain, (b) remove mercury from polluted sites, and (c) hyperaccumulate mercury in aboveground tissues for later harvest. Various parts ofmore » this strategy are being critically tested by examining different genes in model plants and field species and comparing the results to control plants as we recently reviewed (Meagher et al., 2000; Rugh et al., 2000). A positive spin-off from this work on mercury has been a strategy for the phytoremediation of arsenic (Dhankher et al., 2002) and cadmium.« less

Factors influencing tests of auditory processing: a perspective on current issues and relevant concerns.

PubMed

Cacace, Anthony T; McFarland, Dennis J

2013-01-01

Tests of auditory perception, such as those used in the assessment of central auditory processing disorders ([C]APDs), represent a domain in audiological assessment where measurement of this theoretical construct is often confounded by nonauditory abilities due to methodological shortcomings. These confounds include the effects of cognitive variables such as memory and attention and suboptimal testing paradigms, including the use of verbal reproduction as a form of response selection. We argue that these factors need to be controlled more carefully and/or modified so that their impact on tests of auditory and visual perception is only minimal. To advocate for a stronger theoretical framework than currently exists and to suggest better methodological strategies to improve assessment of auditory processing disorders (APDs). Emphasis is placed on adaptive forced-choice psychophysical methods and the use of matched tasks in multiple sensory modalities to achieve these goals. Together, this approach has potential to improve the construct validity of the diagnosis, enhance and develop theory, and evolve into a preferred method of testing. Examination of methods commonly used in studies of APDs. Where possible, currently used methodology is compared to contemporary psychophysical methods that emphasize computer-controlled forced-choice paradigms. In many cases, the procedures used in studies of APD introduce confounding factors that could be minimized if computer-controlled forced-choice psychophysical methods were utilized. Ambiguities of interpretation, indeterminate diagnoses, and unwanted confounds can be avoided by minimizing memory and attentional demands on the input end and precluding the use of response-selection strategies that use complex motor processes on the output end. Advocated are the use of computer-controlled forced-choice psychophysical paradigms in combination with matched tasks in multiple sensory modalities to enhance the prospect of obtaining a valid diagnosis. American Academy of Audiology.

Global investment targets for malaria control and elimination between 2016 and 2030

PubMed Central

Patouillard, Edith; Griffin, Jamie; Bhatt, Samir; Ghani, Azra; Cibulskis, Richard

2017-01-01

Background Access to malaria control interventions falls short of universal health coverage. The Global Technical Strategy for malaria targets at least 90% reduction in case incidence and mortality rates, and elimination in 35 countries by 2030. The potential to reach these targets will be determined in part by investments in malaria. This study estimates the financing required for malaria control and elimination over the 2016–2030 period. Methods A mathematical transmission model was used to explore the impact of increasing intervention coverage on burden and costs. The cost analysis took a public provider perspective covering all 97 malaria endemic countries and territories in 2015. All control interventions currently recommended by the WHO were considered. Cost data were sourced from procurement databases, the peer-reviewed literature, national malaria strategic plans, the WHO-CHOICE project and key informant interviews. Results Annual investments of $6.4 billion (95% uncertainty interval (UI $4.5–$9.0 billion)) by 2020, $7.7 billion (95% UI $5.4–$10.9 billion) by 2025 and $8.7 billion (95% UI $6.0–$12.3 billion) by 2030 will be required to reach the targets set in the Global Technical Strategy. These are equivalent to annual investment per person at risk of malaria of US$3.90 by 2020, US$4.30 by 2025 and US$4.40 by 2030, compared with US$2.30 if interventions were sustained at current coverage levels. The 20 countries with the highest burden in 2015 will require 88% of the total investment. Conclusions Given the challenges in increasing domestic and international funding, the efficient use of currently available resources should be a priority. PMID:29242750

Global investment targets for malaria control and elimination between 2016 and 2030.

PubMed

Patouillard, Edith; Griffin, Jamie; Bhatt, Samir; Ghani, Azra; Cibulskis, Richard

2017-01-01

Access to malaria control interventions falls short of universal health coverage. The Global Technical Strategy for malaria targets at least 90% reduction in case incidence and mortality rates, and elimination in 35 countries by 2030. The potential to reach these targets will be determined in part by investments in malaria. This study estimates the financing required for malaria control and elimination over the 2016-2030 period. A mathematical transmission model was used to explore the impact of increasing intervention coverage on burden and costs. The cost analysis took a public provider perspective covering all 97 malaria endemic countries and territories in 2015. All control interventions currently recommended by the WHO were considered. Cost data were sourced from procurement databases, the peer-reviewed literature, national malaria strategic plans, the WHO-CHOICE project and key informant interviews. Annual investments of $6.4 billion (95% uncertainty interval (UI $4.5-$9.0 billion)) by 2020, $7.7 billion (95% UI $5.4-$10.9 billion) by 2025 and $8.7 billion (95% UI $6.0-$12.3 billion) by 2030 will be required to reach the targets set in the Global Technical Strategy. These are equivalent to annual investment per person at risk of malaria of US$3.90 by 2020, US$4.30 by 2025 and US$4.40 by 2030, compared with US$2.30 if interventions were sustained at current coverage levels. The 20 countries with the highest burden in 2015 will require 88% of the total investment. Given the challenges in increasing domestic and international funding, the efficient use of currently available resources should be a priority.

Atherosclerotic Cardiovascular Disease and Heart Failure in Type 2 Diabetes – Mechanisms, Management, and Clinical Considerations

PubMed Central

Low Wang, Cecilia C.; Hess, Connie N.; Hiatt, William R.; Goldfine, Allison B.

2016-01-01

Cardiovascular disease remains the principal cause of death and disability among patients with diabetes mellitus. Diabetes exacerbates mechanisms underlying atherosclerosis and heart failure. Unfortunately, these mechanisms are not adequately modulated by therapeutic strategies focusing solely on optimal glycemic control with currently available drugs or approaches. In the setting of multi-factorial risk reduction with statins and other lipid lowering agents, anti-hypertensive therapies, and anti-hyperglycemic treatment strategies, cardiovascular complication rates are falling, yet remain higher for patients with diabetes than for those without. This review considers the mechanisms, history, controversies, new pharmacologic agents, and recent evidence for current guidelines for cardiovascular management in the patient with diabetes mellitus to support evidence-based care in the patient with diabetes and heart disease outside of the acute care setting. PMID:27297342

Social inclusion facilitates risky mating behavior in men.

PubMed

Sacco, Donald F; Brown, Christina M; Young, Steven G; Bernstein, Michael J; Hugenberg, Kurt

2011-07-01

Although past research has reliably established unique effects of social exclusion on human cognition and behavior, the current research focuses on the unique effects of social inclusion. Recent evidence indicates that social inclusion leads to enhanced prioritization of reproductive interests. The current study extends these findings by showing that the pursuit of these inclusion-induced reproductive goals occurs in sex-specific ways. Across three experiments, social inclusion led men, but not women, to endorse riskier, more aggressive mating strategies compared to control and socially excluded participants. Specifically, included men were more likely to endorse sexual aggression (Experiment 1), high-risk mate poaching behaviors (Experiment 2), and high-risk mate retention tactics (Experiment 3). These results demonstrate that the experience of social inclusion can affect sex-differentiated preferences for risky mating strategies. © 2011 by the Society for Personality and Social Psychology, Inc

Epidemiological and Economic Evaluation of Alternative On-Farm Management Scenarios for Ovine Footrot in Switzerland

PubMed Central

Zingg, Dana; Steinbach, Sandro; Kuhlgatz, Christian; Rediger, Matthias; Schüpbach-Regula, Gertraud; Aepli, Matteo; Grøneng, Gry M.; Dürr, Salome

2017-01-01

Footrot is a multifactorial infectious disease mostly affecting sheep, caused by the bacteria Dichelobacter nodosus. It causes painful feet lesions resulting in animal welfare issues, weight loss, and reduced wool production, which leads to a considerable economic burden in animal production. In Switzerland, the disease is endemic and mandatory coordinated control programs exist only in some parts of the country. This study aimed to compare two nationwide control strategies and a no intervention scenario with the current situation, and to quantify their net economic effect. This was done by sequential application of a maximum entropy model (MEM), epidemiological simulation, and calculation of net economic effect using the net present value method. Building upon data from a questionnaire, the MEM revealed a nationwide footrot prevalence of 40.2%. Regional prevalence values were used as inputs for the epidemiological model. Under the application of the nationwide coordinated control program without (scenario B) and with (scenario C) improved diagnostics [polymerase chain reaction (PCR) test], the Swiss-wide prevalence decreased within 10 years to 14 and 5%, respectively. Contrary, an increase to 48% prevalence was observed when terminating the current control strategies (scenario D). Management costs included labor and material costs. Management benefits included reduction of fattening time and improved animal welfare, which is valued by Swiss consumers and therefore reduces societal costs. The net economic effect of the alternative scenarios B and C was positive, the one of scenario D was negative and over a period of 17 years quantified at CHF 422.3, 538.3, and −172.3 million (1 CHF = 1.040 US$), respectively. This implies that a systematic Swiss-wide management program under the application of the PCR diagnostic test is the most recommendable strategy for a cost-effective control of footrot in Switzerland. PMID:28560223

Reducing the Use of Pesticides with Site-Specific Application: The Chemical Control of Rhizoctonia solani as a Case of Study for the Management of Soil-Borne Diseases

PubMed Central

Le Cointe, Ronan; Simon, Thomas E.; Delarue, Patrick; Hervé, Maxime; Leclerc, Melen; Poggi, Sylvain

2016-01-01

Reducing our reliance on pesticides is an essential step towards the sustainability of agricultural production. One approach involves the rational use of pesticides combined with innovative crop management. Most control strategies currently focus on the temporal aspect of epidemics, e.g. determining the optimal date for spraying, regardless of the spatial mechanics and ecology of disease spread. Designing innovative pest management strategies incorporating the spatial aspect of epidemics involves thorough knowledge on how disease control affects the life-history traits of the pathogen. In this study, using Rhizoctonia solani/Raphanus sativus as an example of a soil-borne pathosystem, we investigated the effects of a chemical control currently used by growers, Monceren® L, on key epidemiological components (saprotrophic spread and infectivity). We tested the potential “shield effect” of Monceren® L on pathogenic spread in a site-specific application context, i.e. the efficiency of this chemical to contain the spread of the fungus from an infected host when application is spatially localized, in our case, a strip placed between the infected host and a recipient bait. Our results showed that Monceren® L mainly inhibits the saprotrophic spread of the fungus in soil and may prevent the fungus from reaching its host plant. However, perhaps surprisingly we did not detect any significant effect of the fungicide on the pathogen infectivity. Finally, highly localized application of the fungicide—a narrow strip of soil (12.5 mm wide) sprayed with Monceren® L—significantly decreased local transmission of the pathogen, suggesting lowered risk of occurrence of invasive epidemics. Our results highlight that detailed knowledge on epidemiological processes could contribute to the design of innovative management strategies based on precision agriculture tools to improve the efficacy of disease control and reduce pesticide use. PMID:27668731

Micropatterning strategies to engineer controlled cell and tissue architecture in vitro.

PubMed

D'Arcangelo, Elisa; McGuigan, Alison P

2015-01-01

Micropatterning strategies, which enable control over cell and tissue architecture in vitro, have emerged as powerful platforms for modelling tissue microenvironments at different scales and complexities. Here, we provide an overview of popular micropatterning techniques, along with detailed descriptions, to guide new users through the decision making process of which micropatterning procedure to use, and how to best obtain desired tissue patterns. Example techniques and the types of biological observations that can be made are provided from the literature. A focus is placed on microcontact printing to obtain co-cultures of patterned, confluent sheets, and the challenges associated with optimizing this protocol. Many issues associated with microcontact printing, however, are relevant to all micropatterning methodologies. Finally, we briefly discuss challenges in addressing key limitations associated with current micropatterning technologies.

Review of homogeneous charge compression ignition (HCCI) combustion engines and exhaust gas recirculation (EGR) effects on HCCI

NASA Astrophysics Data System (ADS)

Akma Tuan Kamaruddin, Tengku Nordayana; Wahid, Mazlan Abdul; Sies, Mohsin Mohd

2012-06-01

This paper describes the development in ICE which leads to the new advanced combustion mode named Homogeneous Charge Compression Ignition (HCCI). It explains regarding the theory and working principle of HCCI plus the difference of the process in gasoline and diesel fuelled engines. Many of pioneer and recent research works are discussed to get the current state of art about HCCI. It gives a better indication on the potential of this method in improving the fuel efficiency and emission produced by the vehicles' engine. Apart from the advantages, the challenges and future trend of this technology are also included. HCCI is applying few types of control strategy in producing the optimum performance. This paper looks into Exhaust Gas Recirculation (EGR) as one of the control strategies.

HIV reservoirs as obstacles and opportunities for an HIV cure.

PubMed

Chun, Tae-Wook; Moir, Susan; Fauci, Anthony S

2015-06-01

The persistence of HIV reservoirs remains a formidable obstacle to achieving sustained virologic remission in HIV-infected individuals after antiretroviral therapy (ART) is discontinued, even if plasma viremia has been successfully suppressed for prolonged periods of time. Numerous approaches aimed at eradicating the virus, as well as maintaining its prolonged suppression in the absence of ART, have had little success. A better understanding of the pathophysiologic nature of HIV reservoirs and the impact of various interventions on their persistence is essential for the development of successful therapeutic strategies against HIV or the long-term control of infection. Here, we discuss the persistent HIV reservoir as a barrier to cure as well as the current therapeutic strategies aimed at eliminating or controlling the virus in the absence of ART.

Comparing the Maryland Comprehensive Cancer Control Plan With Federal Cancer Prevention and Control Recommendations.

PubMed

Fowler, Stephanie L; Platz, Elizabeth A; Diener-West, Marie; Hokenmaier, Sarah; Truss, Meredith; Lewis, Courtney; Kanarek, Norma F

2015-10-01

Since the introduction of the Affordable Care Act (ACA) in 2012, 11 million more Americans now have access to preventive services via health care coverage. Several prevention-related recommendations issued by the US Preventive Services Task Force (USPSTF), Centers for Disease Control and Prevention (CDC), and Advisory Committee on Immunization Practices (ACIP) are covered under the ACA. State cancer plans often provide prevention strategies, but whether these strategies correspond to federal evidence-based recommendations is unclear. The objective of this article is to assess whether federal evidence-based recommendations, including those covered under the ACA, are included in the Maryland Comprehensive Cancer Control Plan (MCCCP). A total of 19 federal recommendations pertaining to cancer prevention and control were identified. Inclusion of federal cancer-related recommendations by USPSTF, CDC, and ACIP in the MCCCP's goals, objectives, and strategies was examined. Nine of the federal recommendations were issued after the MCCCP's publication. MCCCP recommendations corresponded completely with 4 federal recommendations and corresponded only partially with 3. Reasons for partial correspondence included specification of less restrictive at-risk populations or different intervention implementers. Three federal recommendations were not mentioned in the MCCCP's goals, objectives, and strategies. Many cancer-related federal recommendations were released after the MCCCP's publication and therefore do not appear in the most current version. We recommend that the results of this analysis be considered in the update of the MCCCP. Our findings underscore the need for a periodic scan for changes to federal recommendations and for adjusting state policies and programs to correspond with federal recommendations, as appropriate for Marylanders.

Hidden action or hidden strategy: China's control of its national oil companies

NASA Astrophysics Data System (ADS)

Humphrey, Charles

China's rapid economic growth has been accompanied by parallel growth in energy demand, particularly in demand for oil. Due to political and economic constraints on domestic reform, the CPC has focused on the international dimension through the creation of vertically integrated national oil companies. The foreign investments of these companies have become increasingly controversial due to the high levels of political and financial support afforded them by the CPC. I measure control by employing a model of institutional constraints on state-owned enterprises in conjunction with a managerial variant of Principal Agent theory well suited to political analyses. I conclude that the combination of institutional overlap, the process which led to the formation of the CNOCs as they currently exist and the current overseas activities of the CNOCs all demonstrate that the CPC is in control of the CNOCs.

Impact of Aging and Exercise on Mitochondrial Quality Control in Skeletal Muscle

PubMed Central

Kim, Yuho; Triolo, Matthew

2017-01-01

Mitochondria are characterized by its pivotal roles in managing energy production, reactive oxygen species, and calcium, whose aging-related structural and functional deteriorations are observed in aging muscle. Although it is still unclear how aging alters mitochondrial quality and quantity in skeletal muscle, dysregulation of mitochondrial biogenesis and dynamic controls has been suggested as key players for that. In this paper, we summarize current understandings on how aging regulates muscle mitochondrial biogenesis, while focusing on transcriptional regulations including PGC-1α, AMPK, p53, mtDNA, and Tfam. Further, we review current findings on the muscle mitochondrial dynamic systems in aging muscle: fusion/fission, autophagy/mitophagy, and protein import. Next, we also discuss how endurance and resistance exercises impact on the mitochondrial quality controls in aging muscle, suggesting possible effective exercise strategies to improve/maintain mitochondrial health. PMID:28656072

Aging and List-Wide Modulations of Strategy Execution:A Study in Arithmetic.

PubMed

Hinault, Thomas; Lemaire, Patrick

2017-01-01

Background/Study Context: This study aimed at further our understanding of the cognitive processes involved during strategy execution, and how the processes involved change with age. More specifically, the main goal was to investigate whether poorer-strategy effects (i.e., poorer performance when a cued strategy is not the best) and sequential modulations of poorer-strategy effects (i.e., decreased poorer-strategy effects on current problems following poorer-strategy problems compared with after better-strategy problems) are influenced by proportions of poorer-strategy problems. We used a computational estimation task (i.e., providing approximate products to two-digit multiplication problems such as 38 × 74) with problems sets including 75%, 50%, or 25% of poorer-strategy problems (i.e., participants have to estimate products with another strategy than the better strategy). The remaining problems were cued with the better strategy. Age-related differences were also investigated. We found that proportions of poorer-strategy problems influenced sequential modulations of poorer-strategy effects. Indeed, sequential modulations of poorer-strategy effects were larger when proportions of poorer-strategy problems were equal than unequal. Moreover, proportion effects were different for young and older adults, as older adults benefited more from low proportions of poorer-strategy problems compared with young adults. These findings have important implications regarding cognitive control mechanisms underlying both list-wide and trial-to-trial modulations of strategy execution, and how these processes change during aging.

Electrochemical pore filling strategy for controlled growth of magnetic and metallic nanowire arrays with large area uniformity

NASA Astrophysics Data System (ADS)

Arefpour, M.; Almasi Kashi, M.; Ramazani, A.; Montazer, A. H.

2016-07-01

While a variety of template-based strategies have been developed in the fabrication of nanowires (NWs), a uniform pore filling across the template still poses a major challenge. Here, we present a large area controlled pore filling strategy in the reproducible fabrication of various magnetic and metallic NW arrays, embedded inside anodic aluminum oxide templates. Using a diffusive pulsed electrodeposition (DPED) technique, this versatile strategy relies on the optimized filling of branched nanopores at the bottom of templates with Cu. Serving the Cu filled nanopores as appropriate nucleation sites, the DPED is followed by a uniform and homogeneous deposition of magnetic (Ni and Fe) and metallic (Cu and Zn) NWs at a current density of 50 mA cm-2 for an optimal thickness of alumina barrier layer (˜18 nm). Our strategy provides large area uniformity (exceeding 400 μm2) in the fabrication of 16 μm long free-standing NW arrays. Using hysteresis loop measurements and scanning electron microscopy images, the electrodeposition efficiency (EE) and pore filling percentage (F p) are evaluated, leading to maximum EE and F p values of 91% and 95% for Ni and Zn, respectively. Moreover, the resulting NW arrays are found to be highly crystalline. Accordingly, the DPED technique is capable of cheaply and efficiently controlling NW growth over a large area, providing a tool for various nanoscale applications including biomedical devices, electronics, photonics, magnetic storage medium and nanomagnet computing.

Electrochemical pore filling strategy for controlled growth of magnetic and metallic nanowire arrays with large area uniformity.

PubMed

Arefpour, M; Kashi, M Almasi; Ramazani, A; Montazer, A H

2016-06-01

While a variety of template-based strategies have been developed in the fabrication of nanowires (NWs), a uniform pore filling across the template still poses a major challenge. Here, we present a large area controlled pore filling strategy in the reproducible fabrication of various magnetic and metallic NW arrays, embedded inside anodic aluminum oxide templates. Using a diffusive pulsed electrodeposition (DPED) technique, this versatile strategy relies on the optimized filling of branched nanopores at the bottom of templates with Cu. Serving the Cu filled nanopores as appropriate nucleation sites, the DPED is followed by a uniform and homogeneous deposition of magnetic (Ni and Fe) and metallic (Cu and Zn) NWs at a current density of 50 mA cm -2 for an optimal thickness of alumina barrier layer (∼18 nm). Our strategy provides large area uniformity (exceeding 400 μm 2 ) in the fabrication of 16 μm long free-standing NW arrays. Using hysteresis loop measurements and scanning electron microscopy images, the electrodeposition efficiency (EE) and pore filling percentage (F p ) are evaluated, leading to maximum EE and F p values of 91% and 95% for Ni and Zn, respectively. Moreover, the resulting NW arrays are found to be highly crystalline. Accordingly, the DPED technique is capable of cheaply and efficiently controlling NW growth over a large area, providing a tool for various nanoscale applications including biomedical devices, electronics, photonics, magnetic storage medium and nanomagnet computing.

Youth indoor tanning and skin cancer prevention: lessons from tobacco control.

PubMed

Seidenberg, Andrew B; Mahalingam-Dhingra, Aditya; Weinstock, Martin A; Sinclair, Craig; Geller, Alan C

2015-02-01

Youth use of ultraviolet-emitting indoor tanning beds represents a present and emerging public health crisis. Nearly 30% of white female high school students report tanning indoors, and a quarter of high school tanners have used a tanning bed more than 20 times in the past year. Despite the significant health risks of tanning beds, including potentially deadly melanoma and eye problems, limited actions have been taken in the U.S. to protect youth. Tobacco control policies and campaigns, which have sharply reduced youth smoking, may provide a useful framework to control indoor tanning among young people. This article describes several evidence-based tobacco control strategies with potential applicability to indoor tanning within the context of the U.S. Further, current tobacco control policies and current indoor tanning policies in the U.S. are compared, and recommendations on how to curtail youth indoor tanning are discussed. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Reactive navigation for autonomous guided vehicle using neuro-fuzzy techniques

NASA Astrophysics Data System (ADS)

Cao, Jin; Liao, Xiaoqun; Hall, Ernest L.

1999-08-01

A Neuro-fuzzy control method for navigation of an Autonomous Guided Vehicle robot is described. Robot navigation is defined as the guiding of a mobile robot to a desired destination or along a desired path in an environment characterized by as terrain and a set of distinct objects, such as obstacles and landmarks. The autonomous navigate ability and road following precision are mainly influenced by its control strategy and real-time control performance. Neural network and fuzzy logic control techniques can improve real-time control performance for mobile robot due to its high robustness and error-tolerance ability. For a mobile robot to navigate automatically and rapidly, an important factor is to identify and classify mobile robots' currently perceptual environment. In this paper, a new approach of the current perceptual environment feature identification and classification, which are based on the analysis of the classifying neural network and the Neuro- fuzzy algorithm, is presented. The significance of this work lies in the development of a new method for mobile robot navigation.

Impact of vectorborne parasitic neglected tropical diseases on child health.

PubMed

Barry, Meagan A; Murray, Kristy O; Hotez, Peter J; Jones, Kathryn M

2016-07-01

Chagas disease, leishmaniasis, onchocerciasis and lymphatic filariasis are all vectorborne neglected tropical diseases (NTDs) that are responsible for significant disease burden in impoverished children and adults worldwide. As vectorborne parasitic diseases, they can all be targeted for elimination through vector control strategies. Examples of successful vector control programmes for these diseases over the past two decades have included the Southern Cone Initiative against Chagas disease, the Kala-azar Control Scheme against leishmaniasis, the Onchocerciasis Control Programme and the lymphatic filariasis control programme in The Gambia. A common vector control component in all of these programmes is the use of adulticides including dichlorodiphenyltrichloroethane and newer synthetic pyrethroid insecticides against the insect vectors of disease. Household spraying has been used against Chagas disease and leishmaniasis, and insecticide-treated bed nets have helped prevent leishmaniasis and lymphatic filariasis. Recent trends in vector control focus on collaborations between programmes and sectors to achieve integrated vector management that addresses the holistic vector control needs of a community rather than approaching it on a disease-by-disease basis, with the goals of increased efficacy, sustainability and cost-effectiveness. As evidence of vector resistance to currently used insecticide regimens emerges, research to develop new and improved insecticides and novel control strategies will be critical in reducing disease burden. In the quest to eliminate these vectorborne NTDs, efforts need to be made to continue existing control programmes, further implement integrated vector control strategies and stimulate research into new insecticides and control methods. 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/

Prevalence of behavior changing strategies in fitness video games: theory-based content analysis.

PubMed

Lyons, Elizabeth Jane; Hatkevich, Claire

2013-05-07

Fitness video games are popular, but little is known about their content. Because many contain interactive tools that mimic behavioral strategies from weight loss intervention programs, it is possible that differences in content could affect player physical activity and/or weight outcomes. There is a need for a better understanding of what behavioral strategies are currently available in fitness games and how they are implemented. The purpose of this study was to investigate the prevalence of evidence-based behavioral strategies across fitness video games available for home use. Games available for consoles that used camera-based controllers were also contrasted with games available for a console that used handheld motion controllers. Fitness games (N=18) available for three home consoles were systematically identified and play-tested by 2 trained coders for at least 3 hours each. In cases of multiple games from one series, only the most recently released game was included. The Sony PlayStation 3 and Microsoft Xbox360 were the two camera-based consoles, and the Nintendo Wii was the handheld motion controller console. A coding list based on a taxonomy of behavioral strategies was used to begin coding. Codes were refined in an iterative process based on data found during play-testing. The most prevalent behavioral strategies were modeling (17/18), specific performance feedback (17/18), reinforcement (16/18), caloric expenditure feedback (15/18), and guided practice (15/18). All games included some kind of feedback on performance accuracy, exercise frequency, and/or fitness progress. Action planning (scheduling future workouts) was the least prevalent of the included strategies (4/18). Twelve games included some kind of social integration, with nine of them providing options for real-time multiplayer sessions. Only two games did not feature any kind of reward. Games for the camera-based consoles (mean 12.89, SD 2.71) included a greater number of strategies than those for the handheld motion controller console (mean 10.00, SD 2.74, P=.04). Behavioral strategies for increasing self-efficacy and self-regulation are common in home console fitness video games. Social support and reinforcement occurred in approximately half of the studied games. Strategy prevalence varies by console type, partially due to greater feedback afforded by camera-based controllers. Experimental studies are required to test the effects of these strategies when delivered as interactive tools, as this medium may represent an innovative platform for disseminating evidence-based behavioral weight loss intervention components.

Prevalence of Behavior Changing Strategies in Fitness Video Games: Theory-Based Content Analysis

PubMed Central

Hatkevich, Claire

2013-01-01

Background Fitness video games are popular, but little is known about their content. Because many contain interactive tools that mimic behavioral strategies from weight loss intervention programs, it is possible that differences in content could affect player physical activity and/or weight outcomes. There is a need for a better understanding of what behavioral strategies are currently available in fitness games and how they are implemented. Objective The purpose of this study was to investigate the prevalence of evidence-based behavioral strategies across fitness video games available for home use. Games available for consoles that used camera-based controllers were also contrasted with games available for a console that used handheld motion controllers. Methods Fitness games (N=18) available for three home consoles were systematically identified and play-tested by 2 trained coders for at least 3 hours each. In cases of multiple games from one series, only the most recently released game was included. The Sony PlayStation 3 and Microsoft Xbox360 were the two camera-based consoles, and the Nintendo Wii was the handheld motion controller console. A coding list based on a taxonomy of behavioral strategies was used to begin coding. Codes were refined in an iterative process based on data found during play-testing. Results The most prevalent behavioral strategies were modeling (17/18), specific performance feedback (17/18), reinforcement (16/18), caloric expenditure feedback (15/18), and guided practice (15/18). All games included some kind of feedback on performance accuracy, exercise frequency, and/or fitness progress. Action planning (scheduling future workouts) was the least prevalent of the included strategies (4/18). Twelve games included some kind of social integration, with nine of them providing options for real-time multiplayer sessions. Only two games did not feature any kind of reward. Games for the camera-based consoles (mean 12.89, SD 2.71) included a greater number of strategies than those for the handheld motion controller console (mean 10.00, SD 2.74, P=.04). Conclusions Behavioral strategies for increasing self-efficacy and self-regulation are common in home console fitness video games. Social support and reinforcement occurred in approximately half of the studied games. Strategy prevalence varies by console type, partially due to greater feedback afforded by camera-based controllers. Experimental studies are required to test the effects of these strategies when delivered as interactive tools, as this medium may represent an innovative platform for disseminating evidence-based behavioral weight loss intervention components. PMID:23651701

Biotechnological application of functional genomics towards plant-parasitic nematode control.

PubMed

Li, Jiarui; Todd, Timothy C; Lee, Junghoon; Trick, Harold N

2011-12-01

Plant-parasitic nematodes are primary biotic factors limiting the crop production. Current nematode control strategies include nematicides, crop rotation and resistant cultivars, but each has serious limitations. RNA interference (RNAi) represents a major breakthrough in the application of functional genomics for plant-parasitic nematode control. RNAi-induced suppression of numerous genes essential for nematode development, reproduction or parasitism has been demonstrated, highlighting the considerable potential for using this strategy to control damaging pest populations. In an effort to find more suitable and effective gene targets for silencing, researchers are employing functional genomics methodologies, including genome sequencing and transcriptome profiling. Microarrays have been used for studying the interactions between nematodes and plant roots and to measure both plants and nematodes transcripts. Furthermore, laser capture microdissection has been applied for the precise dissection of nematode feeding sites (syncytia) to allow the study of gene expression specifically in syncytia. In the near future, small RNA sequencing techniques will provide more direct information for elucidating small RNA regulatory mechanisms in plants and specific gene silencing using artificial microRNAs should further improve the potential of targeted gene silencing as a strategy for nematode management. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

The prospect of applying chemical elicitors and plant strengtheners to enhance the biological control of crop pests

PubMed Central

Sobhy, Islam S.; Erb, Matthias; Lou, Yonggen; Turlings, Ted C. J.

2014-01-01

An imminent food crisis reinforces the need for novel strategies to increase crop yields worldwide. Effective control of pest insects should be part of such strategies, preferentially with reduced negative impact on the environment and optimal protection and utilization of existing biodiversity. Enhancing the presence and efficacy of native biological control agents could be one such strategy. Plant strengthener is a generic term for several commercially available compounds or mixtures of compounds that can be applied to cultivated plants in order to ‘boost their vigour, resilience and performance’. Studies into the consequences of boosting plant resistance against pests and diseases on plant volatiles have found a surprising and dramatic increase in the plants' attractiveness to parasitic wasps. Here, we summarize the results from these studies and present new results from assays that illustrate the great potential of two commercially available resistance elicitors. We argue that plant strengtheners may currently be the best option to enhance the attractiveness of cultivated plants to biological control agents. Other options, such as the genetic manipulation of the release of specific volatiles may offer future solutions, but in most systems, we still miss fundamental knowledge on which key attractants should be targeted for this approach. PMID:24535390

[Strategies for reducing risks in smoking: opportunity or threat].

PubMed

Córdoba, Rodrigo; Nerín, Isabel

2009-12-01

The smoking control policies recommended by the World Health Organisation have achieved a slight decrease in smoking prevalence in the developed countries, although associated mortality is still very high. The use of tobacco products other than cigarettes and even medicinal nicotine (known as nicotine replacement therapy (NRT)) has been proposed as a risk reduction strategy. Among the tobacco products with less individual risk than cigarettes would be any type of tobacco without smoke (smokeless) with a low content in nitrosamines and modified cigarettes; both forms included under the PREP (Potentially Reduced Exposure Products) concept. The idea would be to promote these products among those who cannot quit smoking or wish to reduce their risk without giving up nicotine intake. The possible effects of risk reduction strategies, including PREP, on the decreased prevalence and morbidity and mortality are reviewed, and the possible implications that this measure could have in our country are analysed. Tobacco control measures in Spain are recent and still insufficient. Therefore, the current priority in Spain is the development of policies of control that have shown to more than effective. The marketing and advertising of new tobacco products, even with reduced potential risk, seems more a serious threat than an opportunity for the development of smoking control policies.

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.

Can training in a real-time strategy video game attenuate cognitive decline in older adults?

PubMed

Basak, Chandramallika; Boot, Walter R; Voss, Michelle W; Kramer, Arthur F

2008-12-01

Declines in various cognitive abilities, particularly executive control functions, are observed in older adults. An important goal of cognitive training is to slow or reverse these age-related declines. However, opinion is divided in the literature regarding whether cognitive training can engender transfer to a variety of cognitive skills in older adults. In the current study, the authors trained older adults in a real-time strategy video game for 23.5 hr in an effort to improve their executive functions. A battery of cognitive tasks, including tasks of executive control and visuospatial skills, were assessed before, during, and after video-game training. The trainees improved significantly in the measures of game performance. They also improved significantly more than the control participants in executive control functions, such as task switching, working memory, visual short-term memory, and reasoning. Individual differences in changes in game performance were correlated with improvements in task switching. The study has implications for the enhancement of executive control processes of older adults. Copyright (c) 2009 APA, all rights reserved.

The Canadian effort to prevent and control hypertension: can other countries adopt Canadian strategies?

PubMed

Campbell, Norm R C; Sheldon, Tobe

2010-07-01

To indicate the key elements of current Canadian programs to treat and control hypertension. In the early 1990s Canada had a hypertension treatment and control rate of 13%. A Canadian strategy to prevent and control hypertension was developed and a coalition of national organizations and volunteers formed to develop increasingly extensive programs. The Canadian effort was largely based on annually updated hypertension management recommendations, an integrated and extensive hypertension knowledge translation program and an increasingly comprehensive outcomes assessment program. After the start of the annual process in 1999, there were very large increases in diagnosis and hypertension treatment coupled with dropping rates of cardiovascular disease. More recent initiatives include an extensive education program for the public and people with hypertension, a program to reduce dietary salt and a funded leadership position. The treatment and control rate increased to 66% when last assessed (2007-2009). The study describes important aspects of the Canadian hypertension management programs to aid those wishing to develop similar programs. Many of the programs could be fully or partially implemented by other countries.

Improved direct torque control of an induction generator used in a wind conversion system connected to the grid.

PubMed

Abdelli, Radia; Rekioua, Djamila; Rekioua, Toufik; Tounzi, Abdelmounaïm

2013-07-01

This paper presents a modulated hysteresis direct torque control (MHDTC) applied to an induction generator (IG) used in wind energy conversion systems (WECs) connected to the electrical grid through a back-to-back converter. The principle of this strategy consists in superposing to the torque reference a triangular signal, as in the PWM strategy, with the desired switching frequency. This new modulated reference is compared to the estimated torque by using a hysteresis controller as in the classical direct torque control (DTC). The aim of this new approach is to lead to a constant frequency and low THD in grid current with a unit power factor and a minimum voltage variation despite the wind variation. To highlight the effectiveness of the proposed method, a comparison was made with classical DTC and field oriented control method (FOC). The obtained simulation results, with a variable wind profile, show an adequate dynamic of the conversion system using the proposed method compared to the classical approaches. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Competing effects of pain and fear of pain on postural control in low back pain?

PubMed

Mazaheri, Masood; Heidari, Elham; Mostamand, Javid; Negahban, Hossein; van Dieen, Jaap H

2014-12-01

A cross-sectional, observational study. To determine whether pain and fear of pain have competing effects on postural sway in patients with low back pain (LBP). Competing effects of pain and pain-related fear on postural control can be proposed as the likely explanation for inconsistent results regarding postural sway in the LBP literature. We hypothesized that although pain might increase postural sway, fear of pain might reduce sway through an increased cognitive effort or increased cocontraction to restrict body movement. The cognitive strategy would be less effective under dual-task conditions and the cocontraction strategy was expected to be less effective when standing on a narrow base of support surface. Postural sway was measured in combined conditions of base of support (full and narrow) and cognitive loading (single and dual tasks) in 3 experimental groups with current LBP, recent LBP, and no LBP. Sway amplitude, path length, mean power frequency, and sample entropy were extracted from center-of-pressure data. The current-LBP group and recent-LBP group reported significantly different levels of pain, but similar levels of pain catastrophizing and kinesiophobia. The current-LBP group tended to display larger sway amplitudes in the anteroposterior direction compared with the other 2 groups. Mean power frequency values in mediolateral direction were lower in patients with the current LBP compared with recent LBP. Smaller sample entropy was found in the current-LBP group than the other groups in most experimental conditions, particularly when standing on a narrow base of support. Alterations of postural sway are mostly mediated by pain but not pain-related fear. LBP tends to increase sway amplitude, which seems to be counteracted by increased effort invested in postural control leading to decreased frequency and increased regularity of sway particularly under increased task demands. Cross-sectional study.

[Elimination of iodine deficiency: a challenge for the end of the century].

PubMed

Noguera Zelaya, A

1994-12-01

The purpose of this article is to review some essential elements that should be considered in the development of national and regional strategies for the prevention and control of iodine deficiency disorders. Another objective is to analyze the current status of this deficiency, the criteria and parameters for evaluating the progress of control programs, and the political, legal, and institutional issues that must be borne in mind in order to reach the virtual elimination of iodine deficiency disorders in the present decade.

Novel strategies for controlling Streptococcus pyogenes infection and associated diseases: from potential peptide vaccines to antibody immunotherapy.

PubMed

Pandey, Manisha; Sekuloski, Silvana; Batzloff, Michael R

2009-07-01

Infections caused by group A streptococcus (GAS) represent a public health problem in both developing and developed countries. The current available methods of prevention are either inadequate or ineffective, which is highlighted by the resurgence in invasive GAS infections over the past two decades. The management of GAS and associated diseases requires new and improved approaches. This review discusses various potential approaches in controlling GAS infections, ranging from prophylactic vaccines to antibody immunotherapy.

Performance of unified power quality conditioner (UPQC) based on fuzzy controller for attenuating of voltage and current harmonics

NASA Astrophysics Data System (ADS)

Milood Almelian, Mohamad; Mohd, Izzeldin I.; Asghaiyer Omran, Mohamed; Ullah Sheikh, Usman

2018-04-01

Power quality-related issues such as current and voltage distortions can adversely affect home and industrial appliances. Although several conventional techniques such as the use of passive and active filters have been developed to increase power quality standards, these methods have challenges and are inadequate due to the increasing number of applications. The Unified Power Quality Conditioner (UPQC) is a modern strategy towards correcting the imperfections of voltage and load current supply. A UPQC is a combination of both series and shunt active power filters in a back-to-back manner with a common DC link capacitor. The control of the voltage of the DC link capacitor is important in achieving a desired UPQC performance. In this paper, the UPQC with a Fuzzy logic controller (FLC) was used to precisely eliminate the imperfections of voltage and current harmonics. The results of the simulation studies using MATLAB/Simulink and Simpower system programming for R-L load associated through an uncontrolled bridge rectifier was used to assess the execution process. The UPQC with FLC was simulated for a system with distorted load current and a system with distorted source voltage and load current. The outcome of the comparison of %THD in the load current and source voltage before and after using UPQC for the two cases was presented.

Innovative Assessment of Aviation English in a Virtual World: Windows into Cognitive and Metacognitive Strategies

ERIC Educational Resources Information Center

Park, Moonyoung

2018-01-01

Aviation English proficiency is a core competency in the global air traffic controller profession. There is, however, growing concern about the current ineffective paper-based assessment methods and the severe lack of interactive online testing for such a critical profession, one that should be ideally assessed in an authentic task and situation…

Research Strategies to Reduce Tick Densities and the Risk of Tick-borne Disease Transmission through Host-Targeted Control

USDA-ARS?s Scientific Manuscript database

While white-tailed deer are not reservoir hosts for the Lyme disease agent, Borrelia burgdorferi, they are the keystone host animal on which adult female blacklegged ticks engorge on blood that is essential to production of tick eggs and completion of the life cycle. This session explores current re...