Dynamic power flow controllers

DOEpatents

Divan, Deepakraj M.; Prasai, Anish

2017-03-07

Dynamic power flow controllers are provided. A dynamic power flow controller may comprise a transformer and a power converter. The power converter is subject to low voltage stresses and not floated at line voltage. In addition, the power converter is rated at a fraction of the total power controlled. A dynamic power flow controller controls both the real and the reactive power flow between two AC sources having the same frequency. A dynamic power flow controller inserts a voltage with controllable magnitude and phase between two AC sources; thereby effecting control of active and reactive power flows between two AC sources.

Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors

NASA Technical Reports Server (NTRS)

Burdisso, Ricardo (Inventor); Fuller, Chris R. (Inventor); O'Brien, Walter F. (Inventor); Thomas, Russell H. (Inventor); Dungan, Mary E. (Inventor)

1996-01-01

An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz.

Active control of aircraft engine inlet noise using compact sound sources and distributed error sensors

NASA Technical Reports Server (NTRS)

Burdisso, Ricardo (Inventor); Fuller, Chris R. (Inventor); O'Brien, Walter F. (Inventor); Thomas, Russell H. (Inventor); Dungan, Mary E. (Inventor)

1994-01-01

An active noise control system using a compact sound source is effective to reduce aircraft engine duct noise. The fan noise from a turbofan engine is controlled using an adaptive filtered-x LMS algorithm. Single multi channel control systems are used to control the fan blade passage frequency (BPF) tone and the BPF tone and the first harmonic of the BPF tone for a plane wave excitation. A multi channel control system is used to control any spinning mode. The multi channel control system to control both fan tones and a high pressure compressor BPF tone simultaneously. In order to make active control of turbofan inlet noise a viable technology, a compact sound source is employed to generate the control field. This control field sound source consists of an array of identical thin, cylindrically curved panels with an inner radius of curvature corresponding to that of the engine inlet. These panels are flush mounted inside the inlet duct and sealed on all edges to prevent leakage around the panel and to minimize the aerodynamic losses created by the addition of the panels. Each panel is driven by one or more piezoelectric force transducers mounted on the surface of the panel. The response of the panel to excitation is maximized when it is driven at its resonance; therefore, the panel is designed such that its fundamental frequency is near the tone to be canceled, typically 2000-4000 Hz.

Performance of active feedforward control systems in non-ideal, synthesized diffuse sound fields.

PubMed

Misol, Malte; Bloch, Christian; Monner, Hans Peter; Sinapius, Michael

2014-04-01

The acoustic performance of passive or active panel structures is usually tested in sound transmission loss facilities. A reverberant sending room, equipped with one or a number of independent sound sources, is used to generate a diffuse sound field excitation which acts as a disturbance source on the structure under investigation. The spatial correlation and coherence of such a synthesized non-ideal diffuse-sound-field excitation, however, might deviate significantly from the ideal case. This has consequences for the operation of an active feedforward control system which heavily relies on the acquisition of coherent disturbance source information. This work, therefore, evaluates the spatial correlation and coherence of ideal and non-ideal diffuse sound fields and considers the implications on the performance of a feedforward control system. The system under consideration is an aircraft-typical double panel system, equipped with an active sidewall panel (lining), which is realized in a transmission loss facility. Experimental results for different numbers of sound sources in the reverberation room are compared to simulation results of a comparable generic double panel system excited by an ideal diffuse sound field. It is shown that the number of statistically independent noise sources acting on the primary structure of the double panel system depends not only on the type of diffuse sound field but also on the sample lengths of the processed signals. The experimental results show that the number of reference sensors required for a defined control performance exhibits an inverse relationship to control filter length.

Active sources in the cutoff of centrifugal fans to reduce the blade tones at higher-order duct mode frequencies

NASA Astrophysics Data System (ADS)

Neise, W.; Koopmann, G. H.

1991-01-01

A previously developed (e.g., Neise and Koopmann, 1984; Koopmann et al., 1988) active noise control technique in which the unwanted acoustic signals from centrifugal fans are suppressed by placing two externally driven sources near the cutoff of the casing was applied to the frequency region where not only plane sound waves are propagational in the fan ducts but also higher-order acoustic modes. Using a specially designed fan noise testing facility, the performance of two fans (280-mm impeller diam and 508 mm diam) was monitored with static pressure taps mounted peripherally around the inlet nozzle. Experimental results show that the aerodynamically generated source pressure field around the cutoff is too complex to be successfully counterimaged by only two active sources introduced in this region. It is suggested that, for an efficient application of this noise control technique in the higher-order mode frequency regime, it is neccessary to use an active source involving larger number of individually driven loudspeakers.

Topography of activation deficits in schizophrenia during P300 task related to cognition and structural connectivity.

PubMed

Molina, Vicente; Bachiller, Alejandro; de Luis, Rodrigo; Lubeiro, Alba; Poza, Jesús; Hornero, Roberto; Alonso, Joan Francesc; Mañanas, Miguel Angel; Marqués, Patricia; Romero, Sergio

2018-02-02

The study of cerebral underpinnings of schizophrenia may benefit from the high temporal resolution of electromagnetic techniques, but its spatial resolution is low. However, source imaging approaches such as low-resolution brain electromagnetic tomography (LORETA) allow for an acceptable compromise between spatial and temporal resolutions. We combined LORETA with 32 channels and 3-Tesla diffusion magnetic resonance (Dmr) to study cerebral dysfunction in 38 schizophrenia patients (17 first episodes, FE), compared to 53 healthy controls. The EEG was acquired with subjects performing an odd-ball task. Analyses included an adaptive window of interest to take into account the interindividual variability of P300 latency. We compared source activation patters to distractor (P3a) and target (P3b) tones within- and between-groups. Patients showed a reduced activation in anterior cingulate and lateral and medial prefrontal cortices, as well as inferior/orbital frontal regions. This was also found in the FE patients alone. The activation was directly related to IQ in the patients and controls and to working memory performance in controls. Symptoms were unrelated to source activation. Fractional anisotropy in the tracts connecting lateral prefrontal and anterior cingulate regions predicted source activation in these regions in the patients. These results replicate the source activation deficit found in a previous study with smaller sample size and a lower number of sensors and suggest an association between structural connectivity deficits and functional alterations.

Active control of sound radiation from a vibrating rectangular panel by sound sources and vibration inputs - An experimental comparison

NASA Technical Reports Server (NTRS)

Fuller, C. R.; Hansen, C. H.; Snyder, S. D.

1991-01-01

Active control of sound radiation from a rectangular panel by two different methods has been experimentally studied and compared. In the first method a single control force applied directly to the structure is used with a single error microphone located in the radiated acoustic field. Global attenuation of radiated sound was observed to occur by two main mechanisms. For 'on-resonance' excitation, the control force had the effect of increasing the total panel input impedance presented to the nosie source, thus reducing all radiated sound. For 'off-resonance' excitation, the control force tends not significantly to modify the panel total response amplitude but rather to restructure the relative phases of the modes leading to a more complex vibration pattern and a decrease in radiation efficiency. For acoustic control, the second method, the number of acoustic sources required for global reduction was seen to increase with panel modal order. The mechanism in this case was that the acoustic sources tended to create an inverse pressure distribution at the panel surface and thus 'unload' the panel by reducing the panel radiation impedance. In general, control by structural inputs appears more effective than control by acoustic sources for structurally radiated noise.

Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

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

Shott, Gregory J.

This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclearmore » Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).« less

Where Do Women Get Advice About Weight, Eating, and Physical Activity During Pregnancy?

PubMed

Mercado, Adrian; Marquez, Becky; Abrams, Barbara; Phipps, Maureen G; Wing, Rena R; Phelan, Suzanne

2017-09-01

Most women report not receiving information about gestational weight gain (GWG) from prenatal providers, but less is known about other sources of information and their potential impacts on GWG. The purpose of this study was to investigate sources of information about diet, physical activity, and weight control during pregnancy, and the impact of information sources on maternal GWG. Participants were 183 women with normal weight and 172 women with overweight/obesity who had enrolled in a prenatal lifestyle intervention trial. At 6 weeks postpartum, women were asked whether they had received information about "diet, physical activity, or weight control" from 12 sources uninvolved in the trial (e.g., physician, Internet, and friend) and, if received, the extent to which they followed the advice. Information sources were examined in relation to odds of exceeding Institute of Medicine (IOM) GWG guidelines based on measured weights. Most women reported receiving information from a book (60.6%) or the Internet (58.3%). Advice from physicians, dietitians, or nurses was reported in 55.6%, 48.2%, and 33.9% of women, respectively. Reported receipt of information from physicians was associated with reduced Odds Ratio ([95% Confidence Interval] = 0.55 [0.35-0.88]; p = 0.01) of exceeding IOM GWG guidelines. Reported receipt of information from other sources was not related to GWG. Books and the Internet were the most prevalent information sources reported for prenatal diet, physical activity, and weight control. However, of all sources, only physician provision of information was associated with reduced odds of excessive GWG.

Electrically controlled optical latch and switch requires less current

NASA Technical Reports Server (NTRS)

Pieczonka, W. A.; Roy, M. M.; Yeh, T. H.

1966-01-01

Electrically controlled optical latch consists of a sensitive phototransistor and a solid-state light source. This design requires less current to activate an optically activated switch than in prior art.

RECOGNIZING FARMERS' ATTITUDES AND IMPLEMENTING NONPOINT SOURCE POLLUTION CONTROL POLICIES

EPA Science Inventory

This report examines the role of farmer attitudes and corresponding communication activities in the implementation of nonpoint source water pollution control programs. The report begins with an examination of the basis for and function of attitudes in influencing behavior. The ro...

Categorization of In-use Radioactive Sealed Sources in Egypt

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

Hasan, M.A.; Mohamed, Y.T.; El Haleim, K.A.

2006-07-01

Radioactive sealed sources have widespread applications in industry, medicine, research and education. While most sources are of relatively low activity, there are many of medium or very high activity. The mismanagement of high activity sources is responsible for most of the radiological accidents that result in loss of life or disabling injuries. Because of the variety of applications and activities of radioactive sources, a categorization system is necessary so that the controls that are applied to the sources are adequate with its radiological risk. The aim of this work is to use the international Atomic Energy Agency (IAEA) categorization systemmore » to provide a simple, logical system for grading radioactive sealed sources in Egypt. The categorizations of radioactive sealed sources are based on their potential to cause harm to human health. This study revealed that total of 1916 sources have been used in Egypt in the different applications with a total activity of 89400 Ci according to available data in October 2005. (authors)« less

Active room compensation for sound reinforcement using sound field separation techniques.

PubMed

Heuchel, Franz M; Fernandez-Grande, Efren; Agerkvist, Finn T; Shabalina, Elena

2018-03-01

This work investigates how the sound field created by a sound reinforcement system can be controlled at low frequencies. An indoor control method is proposed which actively absorbs the sound incident on a reflecting boundary using an array of secondary sources. The sound field is separated into incident and reflected components by a microphone array close to the secondary sources, enabling the minimization of reflected components by means of optimal signals for the secondary sources. The method is purely feed-forward and assumes constant room conditions. Three different sound field separation techniques for the modeling of the reflections are investigated based on plane wave decomposition, equivalent sources, and the Spatial Fourier transform. Simulations and an experimental validation are presented, showing that the control method performs similarly well at enhancing low frequency responses with the three sound separation techniques. Resonances in the entire room are reduced, although the microphone array and secondary sources are confined to a small region close to the reflecting wall. Unlike previous control methods based on the creation of a plane wave sound field, the investigated method works in arbitrary room geometries and primary source positions.

MINE WASTE TECHNOLOGY PROGRAM - UNDERGROUND MINE SOURCE CONTROL DEMONSTRATION PROJECT

EPA Science Inventory

This report presents results of the Mine Waste Technology Program Activity III, Project 8, Underground Mine Source Control Demonstration Project implemented and funded by the U. S. Environmental Protection Agency (EPA) and jointly administered by EPA and the U. S. Department of E...

Decoding of Ankle Flexion and Extension from Cortical Current Sources Estimated from Non-invasive Brain Activity Recording Methods.

PubMed

Mejia Tobar, Alejandra; Hyoudou, Rikiya; Kita, Kahori; Nakamura, Tatsuhiro; Kambara, Hiroyuki; Ogata, Yousuke; Hanakawa, Takashi; Koike, Yasuharu; Yoshimura, Natsue

2017-01-01

The classification of ankle movements from non-invasive brain recordings can be applied to a brain-computer interface (BCI) to control exoskeletons, prosthesis, and functional electrical stimulators for the benefit of patients with walking impairments. In this research, ankle flexion and extension tasks at two force levels in both legs, were classified from cortical current sources estimated by a hierarchical variational Bayesian method, using electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) recordings. The hierarchical prior for the current source estimation from EEG was obtained from activated brain areas and their intensities from an fMRI group (second-level) analysis. The fMRI group analysis was performed on regions of interest defined over the primary motor cortex, the supplementary motor area, and the somatosensory area, which are well-known to contribute to movement control. A sparse logistic regression method was applied for a nine-class classification (eight active tasks and a resting control task) obtaining a mean accuracy of 65.64% for time series of current sources, estimated from the EEG and the fMRI signals using a variational Bayesian method, and a mean accuracy of 22.19% for the classification of the pre-processed of EEG sensor signals, with a chance level of 11.11%. The higher classification accuracy of current sources, when compared to EEG classification accuracy, was attributed to the high number of sources and the different signal patterns obtained in the same vertex for different motor tasks. Since the inverse filter estimation for current sources can be done offline with the present method, the present method is applicable to real-time BCIs. Finally, due to the highly enhanced spatial distribution of current sources over the brain cortex, this method has the potential to identify activation patterns to design BCIs for the control of an affected limb in patients with stroke, or BCIs from motor imagery in patients with spinal cord injury.

Mathematically trivial control of sound using a parametric beam focusing source.

PubMed

Tanaka, Nobuo; Tanaka, Motoki

2011-01-01

By exploiting a case regarded as trivial, this paper presents global active noise control using a parametric beam focusing source (PBFS). As with a dipole model, one is used for a primary sound source and the other for a control sound source, the control effect for minimizing a total acoustic power depends on the distance between the two. When the distance becomes zero, the total acoustic power becomes null, hence nothing less than a trivial case. Because of the constraints in practice, there exist difficulties in placing a control source close enough to a primary source. However, by projecting a sound beam of a parametric array loudspeaker onto the target sound source (primary source), a virtual sound source may be created on the target sound source, thereby enabling the collocation of the sources. In order to further ensure feasibility of the trivial case, a PBFS is then introduced in an effort to meet the size of the two sources. Reflected sound wave of the PBFS, which is tantamount to the virtual sound source output, aims to suppress the primary sound. Finally, a numerical analysis as well as an experiment is conducted, verifying the validity of the proposed methodology.

Activation and evaluation of GaN photocathodes

NASA Astrophysics Data System (ADS)

Qian, Yunsheng; Chang, Benkang; Qiao, Jiangliang; Zhang, Yijun; Fu, Rongguo; Qiu, Yafeng

2009-09-01

Gallium Nitride (GaN) photocathodes are potentially attractive as UV detective materials and electron sources. Based on the activation and evaluation system for GaAs photocathode, which consists of ultra-high vacuum (UHV) activation chamber, multi-information measurement system, X-ray photoelectron spectroscopy (XPS), and ultraviolet ray photoelectron spectroscopy (UPS), the control and measurement system for the activation of UV photocathodes was developed. The developed system, which consists of Xenon lamp, monochromator with scanner, signal-processing module, power control unit of Cs and O source, A/D adapter, digital I/O card, computer and software, can control the activation of GaN photocathodes and measure on-line the spectral response curves of GaN photocathodes. GaN materials on sapphire substrate were grown by Metal-Organic Chemical Vapor Deposition (MOCVD) with p-type Mg doping. The GaN materials were activated by Cs-O. The spectral response and quantum efficiency (QE) were measured and calculated. The experiment results are discussed.

40 CFR 63.11890 - What are my additional general requirements for complying with this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... malfunctions and required monitoring system quality assurance or quality control activities (including, as... malfunctions, or required monitoring system quality assurance or control activities in calculations used to... source, including associated air pollution control components and monitoring system components, in a...

Design and implementation of multichannel global active structural acoustic control for a device casing

NASA Astrophysics Data System (ADS)

Mazur, Krzysztof; Wrona, Stanislaw; Pawelczyk, Marek

2018-01-01

The paper presents the idea and discussion on implementation of multichannel global active noise control systems. As a test plant an active casing is used. It has been developed by the authors to reduce device noise directly at the source by controlling vibration of its casing. To provide global acoustic effect in the whole environment, where the device operates, it requires a number of secondary sources and sensors for each casing wall, thus making the whole active control structure complicated, i.e. with a large number of interacting channels. The paper discloses all details concerning hardware setup and efficient implementation of control algorithms for the multichannel case. A new formulation is presented to introduce the distributed version of the Switched-error Filtered-reference Least Mean Squares (FXLMS) algorithm together with adaptation rate enhancement. The convergence rate of the proposed algorithm is compared with original Multiple-error FXLMS. A number of hints followed from many years of authors' experience on microprocessor control systems design and signal processing algorithms optimization are presented. They can be used for various active control and signal processing applications, both for academic research and commercialization.

First Test of Fan Active Noise Control (ANC) Completed

NASA Technical Reports Server (NTRS)

2005-01-01

With the advent of ultrahigh-bypass engines, the space available for passive acoustic treatment is becoming more limited, whereas noise regulations are becoming more stringent. Active noise control (ANC) holds promise as a solution to this problem. It uses secondary (added) noise sources to reduce or eliminate the offending noise radiation. The first active noise control test on the low-speed fan test bed was a General Electric Company system designed to control either the exhaust or inlet fan tone. This system consists of a "ring source," an induct array of error microphones, and a control computer. Fan tone noise propagates in a duct in the form of spinning waves. These waves are detected by the microphone array, and the computer identifies their spinning structure. The computer then controls the "ring source" to generate waves that have the same spinning structure and amplitude, but 180 out of phase with the fan noise. This computer generated tone cancels the fan tone before it radiates from the duct and is heard in the far field. The "ring source" used in these tests is a cylindrical array of 16 flat-plate acoustic radiators that are driven by thin piezoceramic sheets bonded to their back surfaces. The resulting source can produce spinning waves up to mode 7 at levels high enough to cancel the fan tone. The control software is flexible enough to work on spinning mode orders from -6 to 6. In this test, the fan was configured to produce a tone of order 6. The complete modal (spinning and radial) structure of the tones was measured with two builtin sets of rotating microphone rakes. These rakes provide a measurement of the system performance independent from the control system error microphones. In addition, the far-field noise was measured with a semicircular array of 28 microphones. This test represents the first in a series of tests that demonstrate different active noise control concepts, each on a progressively more complicated modal structure. The tests are in preparation for a demonstration on a flight-type engine.

Active local control of propeller-aircraft run-up noise.

PubMed

Hodgson, Murray; Guo, Jingnan; Germain, Pierre

2003-12-01

Engine run-ups are part of the regular maintenance schedule at Vancouver International Airport. The noise generated by the run-ups propagates into neighboring communities, disturbing the residents. Active noise control is a potentially cost-effective alternative to passive methods, such as enclosures. Propeller aircraft generate low-frequency tonal noise that is highly compatible with active control. This paper presents a preliminary investigation of the feasibility and effectiveness of controlling run-up noise from propeller aircraft using local active control. Computer simulations for different configurations of multi-channel active-noise-control systems, aimed at reducing run-up noise in adjacent residential areas using a local-control strategy, were performed. These were based on an optimal configuration of a single-channel control system studied previously. The variations of the attenuation and amplification zones with the number of control channels, and with source/control-system geometry, were studied. Here, the aircraft was modeled using one or two sources, with monopole or multipole radiation patterns. Both free-field and half-space conditions were considered: for the configurations studied, results were similar in the two cases. In both cases, large triangular quiet zones, with local attenuations of 10 dB or more, were obtained when nine or more control channels were used. Increases of noise were predicted outside of these areas, but these were minimized as more control channels were employed. By combining predicted attenuations with measured noise spectra, noise levels after implementation of an active control system were estimated.

Gas turbine engine active clearance control

NASA Technical Reports Server (NTRS)

Deveau, Paul J. (Inventor); Greenberg, Paul B. (Inventor); Paolillo, Roger E. (Inventor)

1985-01-01

Method for controlling the clearance between rotating and stationary components of a gas turbine engine are disclosed. Techniques for achieving close correspondence between the radial position of rotor blade tips and the circumscribing outer air seals are disclosed. In one embodiment turbine case temperature modifying air is provided in flow rate, pressure and temperature varied as a function of engine operating condition. The modifying air is scheduled from a modulating and mixing valve supplied with dual source compressor air. One source supplies relatively low pressure, low temperature air and the other source supplies relatively high pressure, high temperature air. After the air has been used for the active clearance control (cooling the high pressure turbine case) it is then used for cooling the structure that supports the outer air seal and other high pressure turbine component parts.

Survivability of Autonomous Microgrid during Overload Events

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

Du, Wei; Lasseter, Robert H.; Khalsa, Amrit S.

Grid-forming sources are voltage sources that draw necessary currents to meet any load changes. A load step can cause part or all of these sources to become overloaded in a microgrid. This paper presents an overload mitigation controller that addresses the two overload issues in a microgrid by actively controlling the sources’ frequency. When part of the sources in a microgrid is overloaded, the controller autonomously transfers the extra load to other sources by rapidly reducing its frequency. The frequency difference between sources during transient results in a change of phase angle, which redistributes the power flow. When all sourcesmore » in a microgrid are overloaded, each source keeps dropping the frequency. Therefore, under frequency load shedding can be used to trip the non-critical loads resulting in the survival of microgrid. The advantages of these concepts are that communications between sources are not needed during transient, and the robust voltage control is maintained. Lastly, simulation and field tests from CERTS/AEP microgrid test site verify that the control strategy is effective in both purely inverter-based microgrids and inverter & generator mixed microgrids.« less

Survivability of Autonomous Microgrid during Overload Events

DOE PAGES

Du, Wei; Lasseter, Robert H.; Khalsa, Amrit S.

2018-04-23

Grid-forming sources are voltage sources that draw necessary currents to meet any load changes. A load step can cause part or all of these sources to become overloaded in a microgrid. This paper presents an overload mitigation controller that addresses the two overload issues in a microgrid by actively controlling the sources’ frequency. When part of the sources in a microgrid is overloaded, the controller autonomously transfers the extra load to other sources by rapidly reducing its frequency. The frequency difference between sources during transient results in a change of phase angle, which redistributes the power flow. When all sourcesmore » in a microgrid are overloaded, each source keeps dropping the frequency. Therefore, under frequency load shedding can be used to trip the non-critical loads resulting in the survival of microgrid. The advantages of these concepts are that communications between sources are not needed during transient, and the robust voltage control is maintained. Lastly, simulation and field tests from CERTS/AEP microgrid test site verify that the control strategy is effective in both purely inverter-based microgrids and inverter & generator mixed microgrids.« less

Mine Waste Technology Program. In Situ Source Control Of Acid Generation Using Sulfate-Reducing Bacteria

EPA Science Inventory

This report summarizes the results of the Mine Waste Technology Program (MWTP) Activity III, Project 3, In Situ Source Control of Acid Generation Using Sulfate-Reducing Bacteria, funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by EPA and the U.S....

40 CFR 141.521 - What updated watershed control requirements must my unfiltered system implement to continue to...

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Identify watershed characteristics and activities which may have an adverse effect on source water quality; and (b) Monitor the occurrence of activities which may have an adverse effect on source water quality. ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL...

Experience with ActiveX control for simple channel access

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

Timossi, C.; Nishimura, H.; McDonald, J.

2003-05-15

Accelerator control system applications at Berkeley Lab's Advanced Light Source (ALS) are typically deployed on operator consoles running Microsoft Windows 2000 and utilize EPICS[2]channel access for data access. In an effort to accommodate the wide variety of Windows based development tools and developers with little experience in network programming, ActiveX controls have been deployed on the operator stations. Use of ActiveX controls for use in the accelerator control environment has been presented previously[1]. Here we report on some of our experiences with the use and development of these controls.

Computer controlled fluorometer device and method of operating same

DOEpatents

Kolber, Z.; Falkowski, P.

1990-07-17

A computer controlled fluorometer device and method of operating same, said device being made to include a pump flash source and a probe flash source and one or more sample chambers in combination with a light condenser lens system and associated filters and reflectors and collimators, as well as signal conditioning and monitoring means and a programmable computer means and a software programmable source of background irradiance that is operable according to the method of the invention to rapidly, efficiently and accurately measure photosynthetic activity by precisely monitoring and recording changes in fluorescence yield produced by a controlled series of predetermined cycles of probe and pump flashes from the respective probe and pump sources that are controlled by the computer means. 13 figs.

Computer controlled fluorometer device and method of operating same

DOEpatents

Kolber, Zbigniew; Falkowski, Paul

1990-01-01

A computer controlled fluorometer device and method of operating same, said device being made to include a pump flash source and a probe flash source and one or more sample chambers in combination with a light condenser lens system and associated filters and reflectors and collimators, as well as signal conditioning and monitoring means and a programmable computer means and a software programmable source of background irradiance that is operable according to the method of the invention to rapidly, efficiently and accurately measure photosynthetic activity by precisely monitoring and recording changes in fluorescence yield produced by a controlled series of predetermined cycles of probe and pump flashes from the respective probe and pump sources that are controlled by the computer means.

Analytical investigation of adaptive control of radiated inlet noise from turbofan engines

NASA Technical Reports Server (NTRS)

Risi, John D.; Burdisso, Ricardo A.

1994-01-01

An analytical model has been developed to predict the resulting far field radiation from a turbofan engine inlet. A feedforward control algorithm was simulated to predict the controlled far field radiation from the destructive combination of fan noise and secondary control sources. Numerical results were developed for two system configurations, with the resulting controlled far field radiation patterns showing varying degrees of attenuation and spillover. With one axial station of twelve control sources and error sensors with equal relative angular positions, nearly global attenuation is achieved. Shifting the angular position of one error sensor resulted in an increase of spillover to the extreme sidelines. The complex control inputs for each configuration was investigated to identify the structure of the wave pattern created by the control sources, giving an indication of performance of the system configuration. It is deduced that the locations of the error sensors and the control source configuration are equally critical to the operation of the active noise control system.

Fabrication of selective-area growth InGaN LED by mixed-source hydride vapor-phase epitaxy

NASA Astrophysics Data System (ADS)

Bae, Sung Geun; Jeon, Injun; Jeon, Hunsoo; Kim, Kyoung Hwa; Yang, Min; Yi, Sam Nyung; Lee, Jae Hak; Ahn, Hyung Soo; Yu, Young Moon; Sawaki, Nobuhiko; Kim, Suck-Whan

2018-01-01

We prepared InGaN light-emitting diodes (LEDs) with the active layers grown from a mixed source of Ga-In-N materials on an n-type GaN substrate by a selective-area growth method and three fabrication steps: photolithography, epitaxial layer growth, and metallization. The preparation followed a previously developed experimental process using apparatus for mixed-source hydride vapor-phase epitaxy (HVPE), which consisted of a multi-graphite boat, for insulating against the high temperature and to control the growth rate of epilayers, filled with the mixed source on the inside and a radio-frequency (RF) heating coil for heating to a high temperature (T > 900 °C) and for easy control of temperature outside the source zone. Two types of LEDs were prepared, with In compositions of 11.0 and 6.0% in the InGaN active layer, and room-temperature electroluminescence measurements exhibited a main peak corresponding to the In composition at either 420 or 390 nm. The consecutive growth of InGaN LEDs by the mixed-source HVPE method provides a technique for the production of LEDs with a wide range of In compositions in the active layer.

Multiple-source multiple-harmonic active vibration control of variable section cylindrical structures: A numerical study

NASA Astrophysics Data System (ADS)

Liu, Jinxin; Chen, Xuefeng; Gao, Jiawei; Zhang, Xingwu

2016-12-01

Air vehicles, space vehicles and underwater vehicles, the cabins of which can be viewed as variable section cylindrical structures, have multiple rotational vibration sources (e.g., engines, propellers, compressors and motors), making the spectrum of noise multiple-harmonic. The suppression of such noise has been a focus of interests in the field of active vibration control (AVC). In this paper, a multiple-source multiple-harmonic (MSMH) active vibration suppression algorithm with feed-forward structure is proposed based on reference amplitude rectification and conjugate gradient method (CGM). An AVC simulation scheme called finite element model in-loop simulation (FEMILS) is also proposed for rapid algorithm verification. Numerical studies of AVC are conducted on a variable section cylindrical structure based on the proposed MSMH algorithm and FEMILS scheme. It can be seen from the numerical studies that: (1) the proposed MSMH algorithm can individually suppress each component of the multiple-harmonic noise with an unified and improved convergence rate; (2) the FEMILS scheme is convenient and straightforward for multiple-source simulations with an acceptable loop time. Moreover, the simulations have similar procedure to real-life control and can be easily extended to physical model platform.

Analytical study of acoustic response of a semireverberant enclosure with application to active noise control

NASA Technical Reports Server (NTRS)

Parrott, T. L.; Schein, D. B.; Gridley, D.

1985-01-01

The acoustic response of a semireverberant enclosure with two interacting, velocity-prescribed source distributions was analyzed using standard modal analysis techniques with a view toward a better understanding of active noise control. Different source and enclosure dimensions, source separations, and single-wall admittances were studied over representative frequency bandwidths of 10 Hz with source relative phase as a parameter. Results indicate that power radiated into the enclosure agree qualitatively with the spatial average of the mean square pressure, even though the reverberant field is nondiffuse. Decreases in acoustic power can therefore be used to estimate global noise reduction in a nondiffuse semireverberant environment. As might be expected, parametric studies indicate that maximum power reductions of up to 25 dB can be achieved when secondary and primary sources are compact and closely spaced. Although less success is achieved with increasing frequency and source separation or size, significant suppression of up to 8 dB still occurs over the 1 to 2 Hz bandwidth.

High output lamp with high brightness

DOEpatents

Kirkpatrick, Douglas A.; Bass, Gary K.; Copsey, Jesse F.; Garber, Jr., William E.; Kwong, Vincent H.; Levin, Izrail; MacLennan, Donald A.; Roy, Robert J.; Steiner, Paul E.; Tsai, Peter; Turner, Brian P.

2002-01-01

An ultra bright, low wattage inductively coupled electrodeless aperture lamp is powered by a solid state RF source in the range of several tens to several hundreds of watts at various frequencies in the range of 400 to 900 MHz. Numerous novel lamp circuits and components are disclosed including a wedding ring shaped coil having one axial and one radial lead, a high accuracy capacitor stack, a high thermal conductivity aperture cup and various other aperture bulb configurations, a coaxial capacitor arrangement, and an integrated coil and capacitor assembly. Numerous novel RF circuits are also disclosed including a high power oscillator circuit with reduced complexity resonant pole configuration, parallel RF power FET transistors with soft gate switching, a continuously variable frequency tuning circuit, a six port directional coupler, an impedance switching RF source, and an RF source with controlled frequency-load characteristics. Numerous novel RF control methods are disclosed including controlled adjustment of the operating frequency to find a resonant frequency and reduce reflected RF power, controlled switching of an impedance switched lamp system, active power control and active gate bias control.

Using particle swarm optimization to enhance PI controller performances for active and reactive power control in wind energy conversion systems

NASA Astrophysics Data System (ADS)

Taleb, M.; Cherkaoui, M.; Hbib, M.

2018-05-01

Recently, renewable energy sources are impacting seriously power quality of the grids in term of frequency and voltage stability, due to their intermittence and less forecasting accuracy. Among these sources, wind energy conversion systems (WECS) received a great interest and especially the configuration with Doubly Fed Induction Generator. However, WECS strongly nonlinear, are making their control not easy by classical approaches such as a PI. In this paper, we continue deepen study of PI controller used in active and reactive power control of this kind of WECS. Particle Swarm Optimization (PSO) is suggested to improve its dynamic performances and its robustness against parameters variations. This work highlights the performances of PSO optimized PI control against classical PI tuned with poles compensation strategy. Simulations are carried out on MATLAB-SIMULINK software.

46 CFR 112.35-7 - Activating means.

Code of Federal Regulations, 2010 CFR

2010-10-01

... POWER SYSTEMS Manually Controlled Emergency Systems Having a Storage Battery or a Diesel Engine or Gas Turbine Driven Generator as the Sole Emergency Power Source § 112.35-7 Activating means. The activating...

46 CFR 112.35-7 - Activating means.

Code of Federal Regulations, 2011 CFR

2011-10-01

... POWER SYSTEMS Manually Controlled Emergency Systems Having a Storage Battery or a Diesel Engine or Gas Turbine Driven Generator as the Sole Emergency Power Source § 112.35-7 Activating means. The activating...

Active noise attenuation in ventilation windows.

PubMed

Huang, Huahua; Qiu, Xiaojun; Kang, Jian

2011-07-01

The feasibility of applying active noise control techniques to attenuate low frequency noise transmission through a natural ventilation window into a room is investigated analytically and experimentally. The window system is constructed by staggering the opening sashes of a spaced double glazing window to allow ventilation and natural light. An analytical model based on the modal expansion method is developed to calculate the low frequency sound field inside the window and the room and to be used in the active noise control simulations. The effectiveness of the proposed analytical model is validated by using the finite element method. The performance of the active control system for a window with different source and receiver configurations are compared, and it is found that the numerical and experimental results are in good agreement and the best result is achieved when the secondary sources are placed in the center at the bottom of the staggered window. The extra attenuation at the observation points in the optimized window system is almost equivalent to the noise reduction at the error sensor and the frequency range of effective control is up to 390 Hz in the case of a single channel active noise control system. © 2011 Acoustical Society of America

Dipole source localization of event-related brain activity indicative of an early visual selective attention deficit in ADHD children.

PubMed

Jonkman, L M; Kenemans, J L; Kemner, C; Verbaten, M N; van Engeland, H

2004-07-01

This study was aimed at investigating whether attention-deficit hyperactivity disorder (ADHD) children suffer from specific early selective attention deficits in the visual modality with the aid of event-related brain potentials (ERPs). Furthermore, brain source localization was applied to identify brain areas underlying possible deficits in selective visual processing in ADHD children. A two-channel visual color selection task was administered to 18 ADHD and 18 control subjects in the age range of 7-13 years and ERP activity was derived from 30 electrodes. ADHD children exhibited lower perceptual sensitivity scores resulting in poorer target selection. The ERP data suggested an early selective-attention deficit as manifested in smaller frontal positive activity (frontal selection positivity; FSP) in ADHD children around 200 ms whereas later occipital and fronto-central negative activity (OSN and N2b; 200-400 ms latency) appeared to be unaffected. Source localization explained the FSP by posterior-medial equivalent dipoles in control subjects, which may reflect the contribution of numerous surrounding areas. ADHD children have problems with selective visual processing that might be caused by a specific early filtering deficit (absent FSP) occurring around 200 ms. The neural sources underlying these problems have to be further identified. Source localization also suggested abnormalities in the 200-400 ms time range, pertaining to the distribution of attention-modulated activity in lateral frontal areas.

Frontal and temporal lobe sources for a marker of controlled auditory attention: the negative difference (Nd) event-related potential.

PubMed

Jemel, Boutheina; Oades, Robert D; Oknina, Ljubov; Achenbach, Christiane; Röpcke, Bernd

2003-01-01

Frontal and temporal lobe sources for electrical activity associated with auditory controlled attention (negative difference, Nd) were sought for comparison with those reported to arise from the earlier detection of stimulus-change (mismatch negativity, MMN: Jemel et al. 2002). In two sessions a month apart (T1 and T2), 14 subjects were presented with a 3-tone oddball passively, then as a discrimination task. In EEG recordings (32 sites), Nd was calculated by subtraction of the event-related potential elicited by a non-attended stimulus from that after the same frequency-deviant as target Putative generators in the 180-228 ms latency-range were modelled with brain electrical source analysis and mapped to the modified Montreal brain-atlas. Initial T1-analyses located bilateral Nd dipoles in the superior temporal gyrus (BA22) and the dorsolateral prefrontal cortex (BA8). Re-test allowed estimates of the temporal and spatial extension of activity. Peak activity occurred 14 ms later. Step-by-stepanalysis showed that the best spatial fit for the inverse-solutions extended 3-6 mm from the point sources, but for temporal lobe sources this increased 15 mm caudally. The right mid-frontal source (BA10) was rostral and ventral from that in the left superior frontal gyrus (BAB). T1 and T2 dipole strengths were well correlated. Nd measures of controlled attention localised to areas associated with sustained attention, problem-solving and working-memory. Temporal lobe sources were later and more posterior and medial than for automatic change-detection. Frontal Nd sources were more dorsal on the right and more rostral on the left than MMN dipoles reported for the right inferior frontal and left anterior cingulate. The sequence of information processing is reviewed.

Active control on high-order coherence and statistic characterization on random phase fluctuation of two classical point sources.

PubMed

Hong, Peilong; Li, Liming; Liu, Jianji; Zhang, Guoquan

2016-03-29

Young's double-slit or two-beam interference is of fundamental importance to understand various interference effects, in which the stationary phase difference between two beams plays the key role in the first-order coherence. Different from the case of first-order coherence, in the high-order optical coherence the statistic behavior of the optical phase will play the key role. In this article, by employing a fundamental interfering configuration with two classical point sources, we showed that the high- order optical coherence between two classical point sources can be actively designed by controlling the statistic behavior of the relative phase difference between two point sources. Synchronous position Nth-order subwavelength interference with an effective wavelength of λ/M was demonstrated, in which λ is the wavelength of point sources and M is an integer not larger than N. Interestingly, we found that the synchronous position Nth-order interference fringe fingerprints the statistic trace of random phase fluctuation of two classical point sources, therefore, it provides an effective way to characterize the statistic properties of phase fluctuation for incoherent light sources.

X-ray source safety shutter

DOEpatents

Robinet, McLouis

1977-05-31

An apparatus is provided for controlling the activation of a high energy radiation source having a shutter. The apparatus includes magnets and magnetically responsive switches appropriately placed and interconnected so that only with the shutter and other parts of the source in proper position can safe emission of radiation out an open shutter occur.

Techniques for detection and localization of weak hippocampal and medial frontal sources using beamformers in MEG.

PubMed

Mills, Travis; Lalancette, Marc; Moses, Sandra N; Taylor, Margot J; Quraan, Maher A

2012-07-01

Magnetoencephalography provides precise information about the temporal dynamics of brain activation and is an ideal tool for investigating rapid cognitive processing. However, in many cognitive paradigms visual stimuli are used, which evoke strong brain responses (typically 40-100 nAm in V1) that may impede the detection of weaker activations of interest. This is particularly a concern when beamformer algorithms are used for source analysis, due to artefacts such as "leakage" of activation from the primary visual sources into other regions. We have previously shown (Quraan et al. 2011) that we can effectively reduce leakage patterns and detect weak hippocampal sources by subtracting the functional images derived from the experimental task and a control task with similar stimulus parameters. In this study we assess the performance of three different subtraction techniques. In the first technique we follow the same post-localization subtraction procedures as in our previous work. In the second and third techniques, we subtract the sensor data obtained from the experimental and control paradigms prior to source localization. Using simulated signals embedded in real data, we show that when beamformers are used, subtraction prior to source localization allows for the detection of weaker sources and higher localization accuracy. The improvement in localization accuracy exceeded 10 mm at low signal-to-noise ratios, and sources down to below 5 nAm were detected. We applied our techniques to empirical data acquired with two different paradigms designed to evoke hippocampal and frontal activations, and demonstrated our ability to detect robust activations in both regions with substantial improvements over image subtraction. We conclude that removal of the common-mode dominant sources through data subtraction prior to localization further improves the beamformer's ability to project the n-channel sensor-space data to reveal weak sources of interest and allows more accurate localization.

Active Noise Control of Low Speed Fan Rotor-Stator Modes

NASA Technical Reports Server (NTRS)

Sutliff, Daniel L.; Hu, Ziqiang; Pla, Frederic G.; Heidelberg, Laurence J.

1996-01-01

This report describes the Active Noise Cancellation System designed by General Electric and tested in the NASA Lewis Research Center's 48 inch Active Noise Control Fan. The goal of this study was to assess the feasibility of using wall mounted secondary acoustic sources and sensors within the duct of a high bypass turbofan aircraft engine for active noise cancellation of fan tones. The control system is based on a modal control approach. A known acoustic mode propagating in the fan duct is cancelled using an array of flush-mounted compact sound sources. Controller inputs are signals from a shaft encoder and a microphone array which senses the residual acoustic mode in the duct. The canceling modal signal is generated by a modal controller. The key results are that the (6,0) mode was completely eliminated at 920 Hz and substantially reduced elsewhere. The total tone power was reduced 9.4 dB. Farfield 2BPF SPL reductions of 13 dB were obtained. The (4,0) and (4,1) modes were reduced simultaneously yielding a 15 dB modal PWL decrease. Global attenuation of PWL was obtained using an actuator and sensor system totally contained within the duct.

Reduction of Helicopter Blade-Vortex Interaction Noise by Active Rotor Control Technology

NASA Technical Reports Server (NTRS)

Yu, Yung H.; Gmelin, Bernd; Splettstoesser, Wolf; Brooks, Thomas F.; Philippe, Jean J.; Prieur, Jean

1997-01-01

Helicopter blade-vortex interaction noise is one of the most severe noise sources and is very important both in community annoyance and military detection. Research over the decades has substantially improved basic physical understanding of the mechanisms generating rotor blade-vortex interaction noise and also of controlling techniques, particularly using active rotor control technology. This paper reviews active rotor control techniques currently available for rotor blade vortex interaction noise reduction, including higher harmonic pitch control, individual blade control, and on-blade control technologies. Basic physical mechanisms of each active control technique are reviewed in terms of noise reduction mechanism and controlling aerodynamic or structural parameters of a blade. Active rotor control techniques using smart structures/materials are discussed, including distributed smart actuators to induce local torsional or flapping deformations, Published by Elsevier Science Ltd.

Iridium-192 Production for Cancer Treatment

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

Rostelato, M.E.C.M.; Silva, C.P.G.; Rela, P.R.

2004-10-05

The purpose of this work is to settle a laboratory for Iridium -192 sources production, that is, to determine a wire activation method and to build a hot cell for the wires manipulation, quality control and packaging. The paper relates, mainly, the wire activation method and its quality control. The wire activation is carried out in our nuclear reactor, IEA- R1m.

Active Control of Fan-Generated Tone Noise

NASA Technical Reports Server (NTRS)

Gerhold, Carl H.

1995-01-01

This paper reports on an experiment to control the noise radiated from the inlet of a ducted fan using a time domain active adaptive system. The control ,sound source consists of loudspeakers arranged in a ring around the fan duct. The error sensor location is in the fan duct. The purpose of this experiment is to demonstrate that the in-duct error sensor reduces the mode spillover in the far field, thereby increasing the efficiency of the control system. The control system is found to reduce the blade passage frequency tone significantly in the acoustic far field when the mode orders of the noise source and of the control source are the same, when the dominant wave in the duct is a plane wave. The presence of higher order modes in the duct reduces the noise reduction efficiency, particularly near the mode cut-on where the standing wave component is strong, but the control system converges stably. The control system is stable and converges when the first circumferential mode is generated in the duct. The control system is found to reduce the fan noise in the far field on an arc around the fan inlet by as much as 20 dB with none of the sound amplification associated with mode spillover.

Design, Control, and Modeling of a New Voltage Source Converter for HVDC System

NASA Astrophysics Data System (ADS)

Mohan, Madhan; Singh, Bhim; Ketan Panigrahi, Bijaya

2013-05-01

Abstract: A New Voltage Source Converter (VSC) based on neutral clamped three-level circuit is proposed for High Voltage DC (HVDC) system. The proposed VSC is designed in a multipulse configuration. The converter is operated by Fundamental Frequency Switching (FFS). A new control method is developed for achieving all the necessary control aspects of HVDC system such as independent real and reactive power control, bidirectional real and reactive power control. The basic of the control method is varying the pulse width and by keeping the dc link voltage constant. The steady state and dynamic performances of HVDC system interconnecting two different frequencies network are demonstrated for active and reactive power control. Total number of transformers used in this system are reduced to half in comparison with the two-level VSCs for both active and reactive power control. The performance of the HVDC system is improved in terms of reduced harmonics level even at fundamental frequency switching. The harmonic performance of the designed converter is also studied for different value of the dead angle (β), and the optimized range of the dead angle is achieved for varying reactive power requirement. Simulation results are presented for the designed three level multipulse voltage source converters with the proposed control algorithm.

75 FR 54802 - Account Ownership and Control Report; Notice of Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-09

.... MATTERS TO BE CONSIDERED: Agenda: (1) Sources of Ownership and Control Report Data; and (2) Implementation..., control and related information for all trading accounts active on U.S. futures exchanges and other...

A high accuracy sequential solver for simulation and active control of a longitudinal combustion instability

NASA Technical Reports Server (NTRS)

Shyy, W.; Thakur, S.; Udaykumar, H. S.

1993-01-01

A high accuracy convection scheme using a sequential solution technique has been developed and applied to simulate the longitudinal combustion instability and its active control. The scheme has been devised in the spirit of the Total Variation Diminishing (TVD) concept with special source term treatment. Due to the substantial heat release effect, a clear delineation of the key elements employed by the scheme, i.e., the adjustable damping factor and the source term treatment has been made. By comparing with the first-order upwind scheme previously utilized, the present results exhibit less damping and are free from spurious oscillations, offering improved quantitative accuracy while confirming the spectral analysis reported earlier. A simple feedback type of active control has been found to be capable of enhancing or attenuating the magnitude of the combustion instability.

Active Control of Fan Noise: Feasibility Study. Volume 6; Theoretical Analysis for Coupling of Active Noise Control Actuator Ring Sources to an Annular Duct with Flow

NASA Technical Reports Server (NTRS)

Kraft, R. E.

1996-01-01

The objective of this effort is to develop an analytical model for the coupling of active noise control (ANC) piston-type actuators that are mounted flush to the inner and outer walls of an annular duct to the modes in the duct generated by the actuator motion. The analysis will be used to couple the ANC actuators to the modal analysis propagation computer program for the annular duct, to predict the effects of active suppression of fan-generated engine noise sources. This combined program will then be available to assist in the design or evaluation of ANC systems in fan engine annular exhaust ducts. An analysis has been developed to predict the modes generated in an annular duct due to the coupling of flush-mounted ring actuators on the inner and outer walls of the duct. The analysis has been combined with a previous analysis for the coupling of modes to a cylindrical duct in a FORTRAN computer program to perform the computations. The method includes the effects of uniform mean flow in the duct. The program can be used for design or evaluation purposes for active noise control hardware for turbofan engines. Predictions for some sample cases modeled after the geometry of the NASA Lewis ANC Fan indicate very efficient coupling in both the inlet and exhaust ducts for the m = 6 spinning mode at frequencies where only a single radial mode is cut-on. Radial mode content in higher order cut-off modes at the source plane and the required actuator displacement amplitude to achieve 110 dB SPL levels in the desired mode were predicted. Equivalent cases with and without flow were examined for the cylindrical and annular geometry, and little difference was found for a duct flow Mach number of 0.1. The actuator ring coupling program will be adapted as a subroutine to the cylindrical duct modal analysis and the exhaust duct modal analysis. This will allow the fan source to be defined in terms of characteristic modes at the fan source plane and predict the propagation to the arbitrarily-located ANC source plane. The actuator velocities can then be determined to generate the anti-phase mode. The resulting combined fan source/ANC pressure can then be calculated at any desired wall sensor position. The actuator velocities can be determined manually or using a simulation of a control system feedback loop. This will provide a very useful ANC system design and evaluation tool.

End of Life Decisions for Sealed Radioactive Sources

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

Pryor, Kathryn H.

Sealed radioactive sources are encountered in a wide variety of settings – from household smoke detectors and instrument check sources, through fixed industrial gauges, industrial radiography and well logging sources, to irradiators and medical teletherapy devices. In general, the higher the level of activity in the sealed source, the stricter the regulatory control that is applied to its use, control and ultimate disposition. Lower levels of attention and oversight can and do lead to sources ending up in the wrong place – as orphan sources in uncontrolled storage, disposed in a sanitary landfill, melted down in metal recycling operations andmore » incorporated into consumer products, or handled by an unsuspecting member of the public. There are a range of issues that contribute to the problem of improper disposal of sealed sources, and, in particular, to disused source disposal. General licensed sources and devices are particularly at risk of being disposed incorrectly. Higher activity general licensed sources, although required to be registered with the Nuclear Regulatory Commission (NRC) or Agreement State, receive limited regulatory oversight and are not tracked on a national scale. Users frequently do not consider the full life-cycle costs when procuring sources or devices and discover that they cannot afford to package, transport and dispose of their sources properly. The NRC requirements for decommissioning funding plans and financial assurance are not adequate to cover sealed source transport and disposal costs fully. While there are regulatory limits for storage of disused sources, enforcement is limited and there is no financial incentive for owners to dispose of the sources. In some cases, the lack of availability of approved Department of Transportation (DOT) Type B shipping casks also presents a barrier to sealed source disposal. The report of the Disused Sources Working Group does an excellent job of framing these issues. This article reviews both the issues and the report’s recommendations, which are designed to improve sealed source control and encourage proper disposal of disused sources.« less

NATIONAL MANAGEMENT MEASURES TO CONTROL NONPOINT SOURCE POLLUTION FROM HYDROMODIFICATION

EPA Science Inventory

Hydromodification What Are the Nonpoint Source-Related Problems Associated with Hydromodification? Hydromodification activities have been separated into the categories of channelization and channel modification, dams, and streambank and shoreline erosion. A frequent result of c...

Active noise control using a steerable parametric array loudspeaker.

PubMed

Tanaka, Nobuo; Tanaka, Motoki

2010-06-01

Arguably active noise control enables the sound suppression at the designated control points, while the sound pressure except the targeted locations is likely to augment. The reason is clear; a control source normally radiates the sound omnidirectionally. To cope with this problem, this paper introduces a parametric array loudspeaker (PAL) which produces a spatially focused sound beam due to the attribute of ultrasound used for carrier waves, thereby allowing one to suppress the sound pressure at the designated point without causing spillover in the whole sound field. First the fundamental characteristics of PAL are overviewed. The scattered pressure in the near field contributed by source strength of PAL is then described, which is needed for the design of an active noise control system. Furthermore, the optimal control law for minimizing the sound pressure at control points is derived, the control effect being investigated analytically and experimentally. With a view to tracking a moving target point, a steerable PAL based upon a phased array scheme is presented, with the result that the generation of a moving zone of quiet becomes possible without mechanically rotating the PAL. An experiment is finally conducted, demonstrating the validity of the proposed method.

Application of the Monte Carlo method to estimate doses due to neutron activation of different materials in a nuclear reactor

NASA Astrophysics Data System (ADS)

Ródenas, José

2017-11-01

All materials exposed to some neutron flux can be activated independently of the kind of the neutron source. In this study, a nuclear reactor has been considered as neutron source. In particular, the activation of control rods in a BWR is studied to obtain the doses produced around the storage pool for irradiated fuel of the plant when control rods are withdrawn from the reactor and installed into this pool. It is very important to calculate these doses because they can affect to plant workers in the area. The MCNP code based on the Monte Carlo method has been applied to simulate activation reactions produced in the control rods inserted into the reactor. Obtained activities are introduced as input into another MC model to estimate doses produced by them. The comparison of simulation results with experimental measurements allows the validation of developed models. The developed MC models have been also applied to simulate the activation of other materials, such as components of a stainless steel sample introduced into a training reactors. These models, once validated, can be applied to other situations and materials where a neutron flux can be found, not only nuclear reactors. For instance, activation analysis with an Am-Be source, neutrography techniques in both medical applications and non-destructive analysis of materials, civil engineering applications using a Troxler, analysis of materials in decommissioning of nuclear power plants, etc.

Processes, Procedures, and Methods to Control Pollution Resulting from Silvicultural Activities.

ERIC Educational Resources Information Center

Environmental Protection Agency, Washington, DC. Office of Water Programs.

This report presents brief documentation of silvicultural practices, both those now in use and those in stages of research and development. A majority of the text is concerned with the specific aspects of silvicultural activities which relate to nonpoint source pollution control methods. Analyzed are existing and near future pollution control…

Advanced Wavefront Sensing and Control Testbed (AWCT)

NASA Technical Reports Server (NTRS)

Shi, Fang; Basinger, Scott A.; Diaz, Rosemary T.; Gappinger, Robert O.; Tang, Hong; Lam, Raymond K.; Sidick, Erkin; Hein, Randall C.; Rud, Mayer; Troy, Mitchell

2010-01-01

The Advanced Wavefront Sensing and Control Testbed (AWCT) is built as a versatile facility for developing and demonstrating, in hardware, the future technologies of wave front sensing and control algorithms for active optical systems. The testbed includes a source projector for a broadband point-source and a suite of extended scene targets, a dispersed fringe sensor, a Shack-Hartmann camera, and an imaging camera capable of phase retrieval wavefront sensing. The testbed also provides two easily accessible conjugated pupil planes which can accommodate the active optical devices such as fast steering mirror, deformable mirror, and segmented mirrors. In this paper, we describe the testbed optical design, testbed configurations and capabilities, as well as the initial results from the testbed hardware integrations and tests.

How Patterns of Learning About Sexual Information Among Adolescents Are Related to Sexual Behaviors.

PubMed

Bleakley, Amy; Khurana, Atika; Hennessy, Michael; Ellithorpe, Morgan

2018-03-01

Parents, peers and media are informal sources of sexual information for adolescents. Although the content of sexual information communicated by these sources is known to vary, little is known about what adolescents report actually learning from each source. Data from 1,990 U.S.14-17-year-olds who participated in an online survey in 2015 were used to assess learning about four topics (sex, condoms, hormonal birth control and romantic relationships) from three informal sources (parents, peers, and television and movies). Gender and race differences in learning by source and topic were assessed using t tests. Following a factor analysis, learning about all topics was grouped by source, and regression analyses were conducted to examine associations between learning from each source and three outcomes: sexual activity, condom use and hormonal birth control use. Models included interactions between information sources and race and gender. White adolescents reported learning more from parents and less from media than black adolescents. Compared with males, females learned more about hormonal birth control and less about condoms from their parents, and more about relationships from peers and media. Learning from parents and from peers were positively associated with adolescents' sexual activity (unstandardized coefficients, 0.26 and 0.52, respectively). Learning from parents was positively associated with condom use (odds ratio, 1.5). Adolescents' learning about sex from informal sources varies by race and gender. Future research should examine whether sexual health interventions and message development can capitalize on these differences. Copyright © 2018 by the Guttmacher Institute.

Surface processes in an active rift setting: a source to sink approach from the Sperchios delta, central Greece

NASA Astrophysics Data System (ADS)

Pechlivanidou, Sofia; Cowie, Patience; Gawthorpe, Rob

2015-04-01

This study presents an integrated source to sink approach to understand the controls on the distribution of sediments source areas, sediment routing and downstream fining in the Sperchios rift system, central Greece. The Sperchios Rift forms an active half-graben basin, which is controlled by major NW-SE trending faults. Detailed sedimentological analysis (grain size, macro/micro faunal, geochemical and mineral magnetic analysis) in conjunction with 14C age constraints reveal the stratigraphic evolution of the Sperchios delta, located at the eastern part of the rift, including the presence of a Holocene transgressive - regressive wedge overlying Late Pleistocene alluvial deposits. The process-based stratigraphic model SedFlux2D is used to simulate the delta evolution and model scenarios are compared with the measured data. A series of sensitivity tests are used to explore uncertainties associated with variations in sediment supply, tectonic subsidence rate, and Holocene relative sea level. We discuss the effects of the major controls, in particular the rate of relative sea-level rise and tectonic subsidence rate, on accommodation creation and thus delta architecture in this active rift setting during the Holocene. The transition from transgression to regression is found to be mainly controlled by the slowing rate of relative sea level rise that occurred approximately 5500 kyrs ago. Finally, we compare the sediment volumes and grain size variations preserved in the Sperchios delta to onshore erosion rates inferred from data collected on bedrock erodibility, measurements of downstream fining, as well as stream-power/transport capacity for both transverse and axial drainage networks. This comparison, when combined with information on relative uplift/subsidence patterns due to active extensional tectonics, allows us to develop a semi-quantitative, process-based source-to-sink model for this area.

Future trends of global atmospheric antimony emissions from anthropogenic activities until 2050

NASA Astrophysics Data System (ADS)

Zhou, Junrui; Tian, Hezhong; Zhu, Chuanyong; Hao, Jiming; Gao, Jiajia; Wang, Yong; Xue, Yifeng; Hua, Shenbin; Wang, Kun

2015-11-01

This paper presents the scenario forecast of global atmospheric antimony (Sb) emissions from anthropogenic activities till 2050. The projection scenarios are built based on the comprehensive global antimony emission inventory for the period 1995-2010 which is reported in our previous study. Three scenarios are set up to investigate the future changes of global antimony emissions as well as their source and region contribution characteristics. Trends of activity levels specified as 5 primary source categories are projected by combining the historical trend extrapolation with EIA International energy outlook 2013, while the source-specific dynamic emission factors are determined by applying transformed normal distribution functions. If no major changes in the efficiency of emission control are introduced and keep current air quality legislations (Current Legislation scenario), global antimony emissions will increase by a factor of 2 between 2010 and 2050. The largest increase in Sb emissions is projected from Asia due to large volume of nonferrous metals production and waste incineration. In case of enforcing the pollutant emission standards (Strengthened Control scenario), global antimony emissions in 2050 will stabilize with that of 2010. Moreover, we can anticipate further declines in Sb emissions for all continents with the best emission control performances (Maximum Feasible Technological Reduction scenario). Future antimony emissions from the top 10 largest emitting countries have also been calculated and source category contributions of increasing emissions of these countries present significant diversity. Furthermore, global emission projections in 2050 are distributed within a 1° × 1°latitude/longitude grid. East Asia, Western Europe and North America present remarkable differences in emission intensity under the three scenarios, which implies that source-and-country specific control measures are necessary to be implemented for abating Sb emissions from varied continents and countries in the future.

Development of emissions inventory and identification of sources for priority control in the middle reaches of Yangtze River Urban Agglomerations.

PubMed

Sun, Xiaowei; Cheng, Shuiyuan; Lang, Jianlei; Ren, Zhenhai; Sun, Chao

2018-06-01

This paper presents the first attempt to investigate the emission source control of the Middle Reaches of Yangtze River Urban Agglomerations (MRYRUA), one of the national urban agglomerations in China. An emission inventory of the MRYRUA was developed as inputs to the CAMx model based on county-level activity data obtained by full-coverage investigation and source-based spatial surrogates. A classification technology method for priority control of atmospheric emission sources was introduced and applied in the MRYRUA for the evaluation of the emission sources control on the region-scale and city-scale, respectively. The results demonstrated that the emission sources in the Hefei-centered urban agglomerations contributed the biggest on the mean PM 2.5 concentrations of the MRYRUA and should be taken the priority to control. The emission sources in the Ma'anshan city, Xiangtan city, Hefei city and Wuhan city were the bigger contributors on the mean PM 2.5 concentrations of the MRYRUA among the cities and should be taken the priority to control. In generally, emission sources in cities along the Yangtze River and the tributary should be given the special attention for the regional air quality target attainments. This study can give an understanding of Chinese emissions and provide a valuable preference to policy makers for finding effective mitigation measures and control strategies for reducing national and regional air pollution in China. Copyright © 2017 Elsevier B.V. All rights reserved.

Micro optical fiber light source and sensor and method of fabrication thereof

DOEpatents

Kopelman, Raoul; Tan, Weihong; Shi, Zhong-You

1997-01-01

This invention relates generally to the development of and a method of fabricating a fiber optic micro-light source and sensor (50). An optical fiber micro-light source (50) is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors (22) in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material (60). This process allows significant control of the size of the micro light source (50). Furthermore, photo-chemically attaching an optically active material (60) enables the implementation of the micro-light source in a variety of sensor applications.

Micro optical fiber light source and sensor and method of fabrication thereof

DOEpatents

Kopelman, Raoul; Tan, Weihong; Shi, Zhong-You

1994-01-01

This invention relates generally to the development of and a method of fabricating a micro optical fiber light source. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications.

Micro optical fiber light source and sensor and method of fabrication thereof

DOEpatents

Kopelman, R.; Tan, W.; Shi, Z.Y.

1997-05-06

This invention relates generally to the development of and a method of fabricating a fiber optic micro-light source and sensor. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications. 10 figs.

Micro optical fiber light source and sensor and method of fabrication thereof

DOEpatents

Kopelman, R.; Tan, W.; Shi, Z.Y.

1994-11-01

This invention relates generally to the development of and a method of fabricating a micro optical fiber light source. An optical fiber micro-light source is presented whose aperture is extremely small yet able to act as an intense light source. Light sources of this type have wide ranging applications, including use as micro-sensors in NSOM. Micro-sensor light sources have excellent detection limits as well as photo stability, reversibility, and millisecond response times. Furthermore, a method for manufacturing a micro optical fiber light source is provided. It involves the photo-chemical attachment of an optically active material onto the end surface of an optical fiber cable which has been pulled to form an end with an extremely narrow aperture. More specifically, photopolymerization has been applied as a means to photo-chemically attach an optically active material. This process allows significant control of the size of the micro light source. Furthermore, photo-chemically attaching an optically active material enables the implementation of the micro-light source in a variety of sensor applications. 4 figs.

International Space Station External Contamination Status

NASA Technical Reports Server (NTRS)

Mikatarian, Ron; Soares, Carlos

2000-01-01

PResentation slides examine external contamination requirements; International Space Station (ISS) external contamination sources; ISS external contamination sensitive surfaces; external contamination control; external contamination control for pre-launch verification; flight experiments and observations; the Space Shuttle Orbiter waste water dump, materials outgassing, active vacuum vents; example of molecular column density profile, modeling and analysis tools; sources of outgassing induced contamination analyzed to date, quiescent sources, observations on optical degradation due to induced external contamination in LEO; examples of typical contaminant and depth profiles; and status of the ISS system, material outgassing, thruster plumes, and optical degradation.

40 CFR 35.3115 - Eligible activities of the SRF.

Code of Federal Regulations, 2012 CFR

2012-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE State Water Pollution Control Revolving Funds § 35.3115 Eligible... a nonpoint source pollution control management program under section 319 of the Act; and (c) For...

40 CFR 35.3115 - Eligible activities of the SRF.

Code of Federal Regulations, 2013 CFR

2013-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE State Water Pollution Control Revolving Funds § 35.3115 Eligible... a nonpoint source pollution control management program under section 319 of the Act; and (c) For...

40 CFR 35.3115 - Eligible activities of the SRF.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE State Water Pollution Control Revolving Funds § 35.3115 Eligible... a nonpoint source pollution control management program under section 319 of the Act; and (c) For...

40 CFR 35.3115 - Eligible activities of the SRF.

Code of Federal Regulations, 2014 CFR

2014-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE State Water Pollution Control Revolving Funds § 35.3115 Eligible... a nonpoint source pollution control management program under section 319 of the Act; and (c) For...

40 CFR 35.3115 - Eligible activities of the SRF.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ASSISTANCE STATE AND LOCAL ASSISTANCE State Water Pollution Control Revolving Funds § 35.3115 Eligible... a nonpoint source pollution control management program under section 319 of the Act; and (c) For...

Experimental Verification of Application of Looped System and Centralized Voltage Control in a Distribution System with Renewable Energy Sources

NASA Astrophysics Data System (ADS)

Hanai, Yuji; Hayashi, Yasuhiro; Matsuki, Junya

The line voltage control in a distribution network is one of the most important issues for a penetration of Renewable Energy Sources (RES). A loop distribution network configuration is an effective solution to resolve voltage and distribution loss issues concerned about a penetration of RES. In this paper, for a loop distribution network, the authors propose a voltage control method based on tap change control of LRT and active/reactive power control of RES. The tap change control of LRT takes a major role of the proposed voltage control. Additionally the active/reactive power control of RES supports the voltage control when voltage deviation from the upper or lower voltage limit is unavoidable. The proposed method adopts SCADA system based on measured data from IT switches, which are sectionalizing switch with sensor installed in distribution feeder. In order to check the validity of the proposed voltage control method, experimental simulations using a distribution system analog simulator “ANSWER” are carried out. In the simulations, the voltage maintenance capability in the normal and the emergency is evaluated.

40 CFR 63.51 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES Requirements for Control Technology..., activities, or both within a single contiguous area and under common control that is in a section 112(c... finding and identifying control technology options under this subpart, any information that is available...

40 CFR 63.51 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES Requirements for Control Technology..., activities, or both within a single contiguous area and under common control that is in a section 112(c... finding and identifying control technology options under this subpart, any information that is available...

40 CFR 63.51 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES Requirements for Control Technology..., activities, or both within a single contiguous area and under common control that is in a section 112(c... finding and identifying control technology options under this subpart, any information that is available...

40 CFR 63.51 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES Requirements for Control Technology..., activities, or both within a single contiguous area and under common control that is in a section 112(c... finding and identifying control technology options under this subpart, any information that is available...

40 CFR 63.51 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES Requirements for Control Technology..., activities, or both within a single contiguous area and under common control that is in a section 112(c... finding and identifying control technology options under this subpart, any information that is available...

Weak reward source memory in depression reflects blunted activation of VTA/SN and parahippocampus

PubMed Central

Dobbins, Ian G.; Pizzagalli, Diego A.

2014-01-01

Reward responses in the medial temporal lobes and dopaminergic midbrain boost episodic memory formation in healthy adults, and weak memory for emotionally positive material in depression suggests this mechanism may be dysfunctional in major depressive disorder (MDD). To test this hypothesis, we performed a study in which unmedicated adults with MDD and healthy controls encoded drawings paired with reward or zero tokens during functional magnetic resonance imaging. In a recognition test, participants judged whether drawings were previously associated with the reward token (‘reward source’) or the zero token (‘zero source’). Unlike controls, depressed participants failed to show better memory for drawings from the reward source vs the zero source. Consistent with predictions, controls also showed a stronger encoding response to reward tokens vs zero tokens in the right parahippocampus and dopaminergic midbrain, whereas the MDD group showed the opposite pattern—stronger responses to zero vs reward tokens—in these regions. Differential activation of the dopaminergic midbrain by reward vs zero tokens was positively correlated with the reward source memory advantage in controls, but not depressed participants. These data suggest that weaker memory for positive material in depression reflects blunted encoding responses in the dopaminergic midbrain and medial temporal lobes. PMID:24078019

Data-based diffraction kernels for surface waves from convolution and correlation processes through active seismic interferometry

NASA Astrophysics Data System (ADS)

Chmiel, Malgorzata; Roux, Philippe; Herrmann, Philippe; Rondeleux, Baptiste; Wathelet, Marc

2018-05-01

We investigated the construction of diffraction kernels for surface waves using two-point convolution and/or correlation from land active seismic data recorded in the context of exploration geophysics. The high density of controlled sources and receivers, combined with the application of the reciprocity principle, allows us to retrieve two-dimensional phase-oscillation diffraction kernels (DKs) of surface waves between any two source or receiver points in the medium at each frequency (up to 15 Hz, at least). These DKs are purely data-based as no model calculations and no synthetic data are needed. They naturally emerge from the interference patterns of the recorded wavefields projected on the dense array of sources and/or receivers. The DKs are used to obtain multi-mode dispersion relations of Rayleigh waves, from which near-surface shear velocity can be extracted. Using convolution versus correlation with a grid of active sources is an important step in understanding the physics of the retrieval of surface wave Green's functions. This provides the foundation for future studies based on noise sources or active sources with a sparse spatial distribution.

Development of Real Time Implementation of 5/5 Rule based Fuzzy Logic Controller Shunt Active Power Filter for Power Quality Improvement

NASA Astrophysics Data System (ADS)

Puhan, Pratap Sekhar; Ray, Pravat Kumar; Panda, Gayadhar

2016-12-01

This paper presents the effectiveness of 5/5 Fuzzy rule implementation in Fuzzy Logic Controller conjunction with indirect control technique to enhance the power quality in single phase system, An indirect current controller in conjunction with Fuzzy Logic Controller is applied to the proposed shunt active power filter to estimate the peak reference current and capacitor voltage. Current Controller based pulse width modulation (CCPWM) is used to generate the switching signals of voltage source inverter. Various simulation results are presented to verify the good behaviour of the Shunt active Power Filter (SAPF) with proposed two levels Hysteresis Current Controller (HCC). For verification of Shunt Active Power Filter in real time, the proposed control algorithm has been implemented in laboratory developed setup in dSPACE platform.

T cell immunoregulation in active ocular toxoplasmosis.

PubMed

Cordeiro, Cynthia A; Vieira, Erica L M; Castro, Vinicius M; Dutra, Walderez O; Costa, Rogerio A; Orefice, Juliana L; Campos, Wesley R; Orefice, Fernando; Young, Lucy H; Teixeira, Antonio Lucio

2017-04-01

Toxoplasma gondii infection is an important cause of infectious ocular disease. The physiopathology of retinochoroidal lesions associated with this infection is not completely understood. The present study was undertaken to investigate cytokine production by T cells from individuals with active toxoplasmic retinochoroiditis (TR) comparing with controls. Eighteen patients with active TR and 15 healthy controls (6 controls IgG + to Toxoplasma and 9 negative controls) were included in the study. Peripheral blood mononuclear cells were incubated in the presence or absence of T. gondii antigen (STAg), and stained against CD4, CD8, TNF, IL-10 and IFN-γ. Baseline expression of cytokines was higher in TR/IgG + patients in comparison with controls. Cytokine expression was not increased by STAg in vitro stimulation in controls. After stimulation, TR/IgG + patients' lymphocytes increased cytokine as compared to cultures from both controls. While T cells were the main source of IL-10, but also IFN-γ and TNF, other lymphocyte populations were relevant source of inflammatory cytokines. Interestingly, it was observed a negative correlation between ocular lesion size and IL-10 expression by CD4 + lymphocytes. This study showed that T cells are the main lymphocyte populations expressing IL-10 in patients with TR. Moreover, expression of IL-10 plays a protective role in active TR. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Source-based neurofeedback methods using EEG recordings: training altered brain activity in a functional brain source derived from blind source separation

PubMed Central

White, David J.; Congedo, Marco; Ciorciari, Joseph

2014-01-01

A developing literature explores the use of neurofeedback in the treatment of a range of clinical conditions, particularly ADHD and epilepsy, whilst neurofeedback also provides an experimental tool for studying the functional significance of endogenous brain activity. A critical component of any neurofeedback method is the underlying physiological signal which forms the basis for the feedback. While the past decade has seen the emergence of fMRI-based protocols training spatially confined BOLD activity, traditional neurofeedback has utilized a small number of electrode sites on the scalp. As scalp EEG at a given electrode site reflects a linear mixture of activity from multiple brain sources and artifacts, efforts to successfully acquire some level of control over the signal may be confounded by these extraneous sources. Further, in the event of successful training, these traditional neurofeedback methods are likely influencing multiple brain regions and processes. The present work describes the use of source-based signal processing methods in EEG neurofeedback. The feasibility and potential utility of such methods were explored in an experiment training increased theta oscillatory activity in a source derived from Blind Source Separation (BSS) of EEG data obtained during completion of a complex cognitive task (spatial navigation). Learned increases in theta activity were observed in two of the four participants to complete 20 sessions of neurofeedback targeting this individually defined functional brain source. Source-based EEG neurofeedback methods using BSS may offer important advantages over traditional neurofeedback, by targeting the desired physiological signal in a more functionally and spatially specific manner. Having provided preliminary evidence of the feasibility of these methods, future work may study a range of clinically and experimentally relevant brain processes where individual brain sources may be targeted by source-based EEG neurofeedback. PMID:25374520

General Aviation Interior Noise. Part 2; In-Flight Source/Verification

NASA Technical Reports Server (NTRS)

Unruh, James F.; Till, Paul D.; Palumbo, Daniel L. (Technical Monitor)

2002-01-01

The technical approach made use of the Cessna Model 182E aircraft used in the previous effort as a test bed for noise control application. The present phase of the project reports on flight test results during application of various passive noise treatments in an attempt to verify the noise sources and paths for the aircraft. The data presented establishes the level of interior noise control that can be expected for various passive noise control applications within the aircraft cabin. Subsequent testing will address specific testing to demonstrate the technology available to meet a specified level of noise control by application of passive and/or active noise control technology.

Remembering with gains and losses: effects of monetary reward and punishment on successful encoding activation of source memories.

PubMed

Shigemune, Yayoi; Tsukiura, Takashi; Kambara, Toshimune; Kawashima, Ryuta

2014-05-01

The motivation of getting rewards or avoiding punishments reinforces learning behaviors. Although the neural mechanisms underlying the effect of rewards on episodic memory have been demonstrated, there is little evidence of the effect of punishments on this memory. Our functional magnetic resonance imaging (fMRI) study investigated the effects of monetary rewards and punishments on activation during the encoding of source memories. During encoding, participants memorized words (item) and locations of presented words (source) under 3 conditions (Reward, Punishment, and Control). During retrieval, participants retrieved item and source memories of the words and were rewarded or penalized according to their performance. Source memories encoded with rewards or punishments were remembered better than those without such encoding. fMRI data demonstrated that the ventral tegmental area and substantia nigra and nucleus accumbens activations reflected both the processes of reward and punishment, whereas insular activation increased as a linear function of punishment. Activation in the hippocampus and parahippocampal cortex predicted subsequent retrieval success of source memories. Additionally, correlations between these reward/punishment-related regions and the hippocampus were significant. The successful encoding of source memories could be enhanced by punishments and rewards, and interactions between reward/punishment-related regions and memory-related regions could contribute to memory enhancement by reward and/or punishment.

Remembering with Gains and Losses: Effects of Monetary Reward and Punishment on Successful Encoding Activation of Source Memories

PubMed Central

Shigemune, Yayoi; Tsukiura, Takashi; Kambara, Toshimune; Kawashima, Ryuta

2014-01-01

The motivation of getting rewards or avoiding punishments reinforces learning behaviors. Although the neural mechanisms underlying the effect of rewards on episodic memory have been demonstrated, there is little evidence of the effect of punishments on this memory. Our functional magnetic resonance imaging (fMRI) study investigated the effects of monetary rewards and punishments on activation during the encoding of source memories. During encoding, participants memorized words (item) and locations of presented words (source) under 3 conditions (Reward, Punishment, and Control). During retrieval, participants retrieved item and source memories of the words and were rewarded or penalized according to their performance. Source memories encoded with rewards or punishments were remembered better than those without such encoding. fMRI data demonstrated that the ventral tegmental area and substantia nigra and nucleus accumbens activations reflected both the processes of reward and punishment, whereas insular activation increased as a linear function of punishment. Activation in the hippocampus and parahippocampal cortex predicted subsequent retrieval success of source memories. Additionally, correlations between these reward/punishment-related regions and the hippocampus were significant. The successful encoding of source memories could be enhanced by punishments and rewards, and interactions between reward/punishment-related regions and memory-related regions could contribute to memory enhancement by reward and/or punishment. PMID:23314939

Regulation of Nitrogen Metabolism by GATA Zinc Finger Transcription Factors in Yarrowia lipolytica

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

Pomraning, Kyle R.; Bredeweg, Erin L.; Baker, Scott E.

ABSTRACT Fungi accumulate lipids in a manner dependent on the quantity and quality of the nitrogen source on which they are growing. In the oleaginous yeastYarrowia lipolytica, growth on a complex source of nitrogen enables rapid growth and limited accumulation of neutral lipids, while growth on a simple nitrogen source promotes lipid accumulation in large lipid droplets. Here we examined the roles of nitrogen catabolite repression and its regulation by GATA zinc finger transcription factors on lipid metabolism inY. lipolytica. Deletion of the GATA transcription factor genesgzf3andgzf2resulted in nitrogen source-specific growth defects and greater accumulation of lipids when the cells weremore » growing on a simple nitrogen source. Deletion ofgzf1, which is most similar to activators of genes repressed by nitrogen catabolite repression in filamentous ascomycetes, did not affect growth on the nitrogen sources tested. We examined gene expression of wild-type and GATA transcription factor mutants on simple and complex nitrogen sources and found that expression of enzymes involved in malate metabolism, beta-oxidation, and ammonia utilization are strongly upregulated on a simple nitrogen source. Deletion ofgzf3results in overexpression of genes with GATAA sites in their promoters, suggesting that it acts as a repressor, whilegzf2is required for expression of ammonia utilization genes but does not grossly affect the transcription level of genes predicted to be controlled by nitrogen catabolite repression. Both GATA transcription factor mutants exhibit decreased expression of genes controlled by carbon catabolite repression via the repressormig1, including genes for beta-oxidation, highlighting the complex interplay between regulation of carbon, nitrogen, and lipid metabolism. IMPORTANCENitrogen source is commonly used to control lipid production in industrial fungi. Here we identified regulators of nitrogen catabolite repression in the oleaginous yeastY. lipolyticato determine how the nitrogen source regulates lipid metabolism. We show that disruption of both activators and repressors of nitrogen catabolite repression leads to increased lipid accumulation via activation of carbon catabolite repression through an as yet uncharacterized method.« less

Xtreme Learning Control: Examples of the Open Source Movement's Impact on Our Educational Practice in a University Setting.

ERIC Educational Resources Information Center

Dunlap, Joanna C.; Wilson, Brent G.; Young, David L.

This paper describes how Open Source philosophy, a movement that has developed in opposition to the proprietary software industry, has influenced educational practice in the pursuit of scholarly freedom and authentic learning activities for students and educators. This paper provides a brief overview of the Open Source movement, and describes…

Current steering to activate targeted neural pathways during deep brain stimulation of the subthalamic region

PubMed Central

Chaturvedi, Ashutosh; Foutz, Thomas J.; McIntyre, Cameron C.

2012-01-01

Deep brain stimulation (DBS) has steadily evolved into an established surgical therapy for numerous neurological disorders, most notably Parkinson’s disease (PD). Traditional DBS technology relies on voltage-controlled stimulation with a single source; however, recent engineering advances are providing current-controlled devices with multiple independent sources. These new stimulators deliver constant current to the brain tissue, irrespective of impedance changes that occur around the electrode, and enable more specific steering of current towards targeted regions of interest. In this study, we examined the impact of current steering between multiple electrode contacts to directly activate three distinct neural populations in the subthalamic region commonly stimulated for the treatment of PD: projection neurons of the subthalamic nucleus (STN), globus pallidus internus (GPi) fibers of the lenticular fasiculus, and internal capsule (IC) fibers of passage. We used three-dimensional finite element electric field models, along with detailed multi-compartment cable models of the three neural populations to determine their activations using a wide range of stimulation parameter settings. Our results indicate that selective activation of neural populations largely depends on the location of the active electrode(s). Greater activation of the GPi and STN populations (without activating any side-effect related IC fibers) was achieved by current steering with multiple independent sources, compared to a single current source. Despite this potential advantage, it remains to be seen if these theoretical predictions result in a measurable clinical effect that outweighs the added complexity of the expanded stimulation parameter search space generated by the more flexible technology. PMID:22277548

Low Speed, 2-D Rotor/Stator Active Noise Control at the Source Demonstration

NASA Technical Reports Server (NTRS)

Simonich, John C.; Kousen, Ken A.; Zander, Anthony C.; Bak, Michael; Topol, David A.

1997-01-01

Wake/blade-row interaction noise produced by the Annular Cascade Facility at Purdue University has been modeled using the LINFLO analysis. Actuator displacements needed for complete cancellation of the propagating acoustic response modes have been determined, along with the associated actuator power requirements. As an alternative, weighted least squares minimization of the total far-field sound power using individual actuators has also been examined. Attempts were made to translate the two-dimensional aerodynamic results into three-dimensional actuator requirements. The results lie near the limit of present actuator technology. In order to investigate the concept of noise control at the source for active rotor/stator noise control at the source, various techniques for embedding miniature actuators into vanes were examined. Numerous miniature speaker arrangements were tested and analyzed to determine their suitability as actuators for a demonstration test in the Annular Cascade Facility at Purdue. The best candidates demonstrated marginal performance. An alternative concept to using vane mounted speakers as control actuators was developed and tested. The concept uses compression drivers which are mounted externally to the stator vanes. Each compression driver is connected via a tube to an air cavity in the stator vane, from which the driver signal radiates into the working section of the experimental rig. The actual locations and dimensions of the actuators were used as input parameters for a LINFLO computational analysis of the actuator displacements required for complete cancellation of tones in the Purdue experimental rig. The actuators were designed and an arrangement determined which is compatible with the Purdue experimental rig and instrumentation. Experimental tests indicate that the actuators are capable of producing equivalent displacements greater than the requirements predicted by the LINFLO analysis. The acoustic output of the actuators was also found to be unaffected by the presence of air flow representative of the Purdue experimental rig. A test of the active noise control at the source concept for rotor/stator active noise control was demonstrated. This 2-D test demonstrated conclusively the simultaneous reduction of two acoustic modes. Reductions of over 10 dB were obtained over a wide operating range.

Preliminary experiments on active control of fan noise from a turbofan engine

NASA Technical Reports Server (NTRS)

Thomas, R. H.; Burdisso, R. A.; Fuller, C. R.; O'Brien, W. F.

1993-01-01

In the preliminary experiments reported here, active acoustic sources positioned around the circumference of a turbofan engine were used to control the fan noise radiated forward through the inlet. The main objective was to demonstrate the potential of active techniques to alleviate the noise pollution that will be produced by the next generation of larger engines. A reduction of up to 19 dB in the radiation directivity was demonstrated in a zone that encompasses a 30-deg angle, near the error sensor, while spillover effects were observed toward the lateral direction. The simultaneous control of two tones was also demonstrated using two identical controllers in a parallel control configuration.

PARTICULATE EMISSION MEASUREMENTS FROM CONTROLLED CONSTRUCTION ACTIVITIES

EPA Science Inventory

The report summarized the results of field testing of the effectiveness of control measures for sources of fugitive particulate emissions found at construction sites. The effectiveness of watering temporary, unpaved travel surfaces on emissions of particulate matter with aerodyna...

Harmattan, Saharan heat low, and West African monsoon circulation: modulations on the Saharan dust outflow towards the North Atlantic

NASA Astrophysics Data System (ADS)

Schepanski, Kerstin; Heinold, Bernd; Tegen, Ina

2017-09-01

The outflow of dust from the northern African continent towards the North Atlantic is stimulated by the atmospheric circulation over North Africa, which modulates the spatio-temporal distribution of dust source activation and consequently the entrainment of mineral dust into the boundary layer, as well as the transport of dust out of the source regions. The atmospheric circulation over the North African dust source regions, predominantly the Sahara and the Sahel, is characterized by three major circulation regimes: (1) the harmattan (trade winds), (2) the Saharan heat low (SHL), and (3) the West African monsoon circulation. The strength of the individual regimes controls the Saharan dust outflow by affecting the spatio-temporal distribution of dust emission, transport pathways, and deposition fluxes.This study aims at investigating the atmospheric circulation pattern over North Africa with regard to its role favouring dust emission and dust export towards the tropical North Atlantic. The focus of the study is on summer 2013 (June to August), during which the SALTRACE (Saharan Aerosol Long-range TRansport and Aerosol-Cloud interaction Experiment) field campaign also took place. It involves satellite observations by the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) flying on board the geostationary Meteosat Second Generation (MSG) satellite, which are analysed and used to infer a data set of active dust sources. The spatio-temporal distribution of dust source activation frequencies (DSAFs) allows for linking the diurnal cycle of dust source activations to dominant meteorological controls on dust emission. In summer, Saharan dust source activations clearly differ from dust source activations over the Sahel regarding the time of day when dust emission begins. The Sahara is dominated by morning dust source activations predominantly driven by the breakdown of the nocturnal low-level jet. In contrast, dust source activations in the Sahel are predominantly activated during the second half of the day, when downdrafts associated with deep moist convection are the major atmospheric driver. Complementary to the satellite-based analysis on dust source activations and implications from their diurnal cycle, simulations on atmosphere and dust life cycle were performed using the mesoscale atmosphere-dust model system COSMO-MUSCAT (COSMO: COnsortium for Small-scale MOdelling; MUSCAT: MUltiScale Chemistry Aerosol Transport Model). Fields from this simulation were analysed regarding the variability of the harmattan, the Saharan heat low, and the monsoon circulation as well as their impact on the variability of the Saharan dust outflow towards the North Atlantic. This study illustrates the complexity of the interaction among the three major circulation regimes and their modulation of the North African dust outflow. Enhanced westward dust fluxes frequently appear following a phase characterized by a deep SHL. Ultimately, findings from this study contribute to the quantification of the interannual variability of the atmospheric dust burden.

Active Control of Fan Noise-Feasibility Study. Volume 2: Canceling Noise Source-Design of an Acoustic Plate Radiator Using Piezoceramic Actuators

NASA Technical Reports Server (NTRS)

Pla, F. G.; Rajiyah, H.

1995-01-01

The feasibility of using acoustic plate radiators powered by piezoceramic thin sheets as canceling sources for active control of aircraft engine fan noise is demonstrated. Analytical and numerical models of actuated beams and plates are developed and validated. An optimization study is performed to identify the optimum combination of design parameters that maximizes the plate volume velocity for a given resonance frequency. Fifteen plates with various plate and actuator sizes, thicknesses, and bonding layers were fabricated and tested using results from the optimization study. A maximum equivalent piston displacement of 0.39 mm was achieved with the optimized plate samples tested with only one actuator powered, corresponding to a plate deflection at the center of over 1 millimeter. This is very close to the deflection required for a full size engine application and represents a 160-fold improvement over previous work. Experimental results further show that performance is limited by the critical stress of the piezoceramic actuator and bonding layer rather than by the maximum moment available from the actuator. Design enhancements are described in detail that will lead to a flight-worthy acoustic plate radiator by minimizing actuator tensile stresses and reducing nonlinear effects. Finally, several adaptive tuning methods designed to increase the bandwidth of acoustic plate radiators are analyzed including passive, active, and semi-active approaches. The back chamber pressurization and volume variation methods are investigated experimentally and shown to be simple and effective ways to obtain substantial control over the resonance frequency of a plate radiator. This study shows that piezoceramic-based plate radiators can be a viable acoustic source for active control of aircraft engine fan noise.

PI and fuzzy logic controllers for shunt Active Power Filter--a report.

PubMed

P, Karuppanan; Mahapatra, Kamala Kanta

2012-01-01

This paper presents a shunt Active Power Filter (APF) for power quality improvements in terms of harmonics and reactive power compensation in the distribution network. The compensation process is based only on source current extraction that reduces the number of sensors as well as its complexity. A Proportional Integral (PI) or Fuzzy Logic Controller (FLC) is used to extract the required reference current from the distorted line-current, and this controls the DC-side capacitor voltage of the inverter. The shunt APF is implemented with PWM-current controlled Voltage Source Inverter (VSI) and the switching patterns are generated through a novel Adaptive-Fuzzy Hysteresis Current Controller (A-F-HCC). The proposed adaptive-fuzzy-HCC is compared with fixed-HCC and adaptive-HCC techniques and the superior features of this novel approach are established. The FLC based shunt APF system is validated through extensive simulation for diode-rectifier/R-L loads. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

Open-Source Syringe Pump Library

PubMed Central

Wijnen, Bas; Hunt, Emily J.; Anzalone, Gerald C.; Pearce, Joshua M.

2014-01-01

This article explores a new open-source method for developing and manufacturing high-quality scientific equipment suitable for use in virtually any laboratory. A syringe pump was designed using freely available open-source computer aided design (CAD) software and manufactured using an open-source RepRap 3-D printer and readily available parts. The design, bill of materials and assembly instructions are globally available to anyone wishing to use them. Details are provided covering the use of the CAD software and the RepRap 3-D printer. The use of an open-source Rasberry Pi computer as a wireless control device is also illustrated. Performance of the syringe pump was assessed and the methods used for assessment are detailed. The cost of the entire system, including the controller and web-based control interface, is on the order of 5% or less than one would expect to pay for a commercial syringe pump having similar performance. The design should suit the needs of a given research activity requiring a syringe pump including carefully controlled dosing of reagents, pharmaceuticals, and delivery of viscous 3-D printer media among other applications. PMID:25229451

In vitro and In vivo Postprandial Glycemic Activity of Citrus limetta Peel Flour.

PubMed

Flores-Fernández, José Miguel; Barragán-Álvarez, Carla Patricia; Díaz-Martínez, Nestor Emmanuel; Villanueva-Rodríguez, Socorro; Padilla-Camberos, Eduardo

2017-01-01

Previous studies of Citrus spp. peel have shown hypoglycemic and antioxidant activities. Citrus limetta has been studied for its therapeutic properties. Diabetes mellitus (DM) is a health problem in Mexico and worldwide, that takes a vital importance due to its high incidence. Recently, scientists have searched natural sources to control the disease. In this study, we evaluated the in vitro hypoglycemic activity and in vivo postprandial glycemic effect of C. limetta peel flour by glucose adsorption and retardation assays as well as postprandial serum glucose levels using a group of female Balb-c mice, respectively. C. limetta peel flour showed a glucose adsorption capacity of 16.58 mM, having a similar effect regarding the positive control. The glucose diffusion in the dialysate was elevated, with a glucose dialysis retardation index of 33.79% in a period of 3 h, showing similar results to positive control. Postprandial serum glucose levels in the animal group treated with C. limetta peel flour showed a glucose level of 41.4 mg/dL, being this value significantly lower than negative control group and similar to positive control. Toxicity tests showed good tolerance to the dose of 2000 mg/kg. C. limetta peel flour could act as a source of functional compounds for the control of DM. Citrus limetta peel flour showed a glucose adsorption capacity similar to the positive controlThe glucose diffusion in the dialysate was elevated, showing similar results to positive controlPostprandial serum glucose levels in the animal group treated with C. limetta peel flour showed a glucose level significantly lower than negative control group and similar to positive controlToxicity tests showed good tolerance C. limetta peel flour could act as a source of functional compounds for the control of diabetes mellitus. Abbreviations used: CIATEJ: Center for Research and Assistance in Technology and Design of Jalisco; DM: Diabetes mellitus; FGC: Final glucose concentration; GDRI: Glucose dialysis retardation index; IGC: Initial glucose concentration; OECD: Organization for Economic Cooperation and Development.

40 CFR 52.1037 - Original identification of plan section.

Code of Federal Regulations, 2010 CFR

2010-07-01

... operation of new and modified major stationary sources of pollution in attainment areas. (11) Attainment... review of construction and operation of new and modified major stationary sources of pollution in non... involvement in federally funded air pollution control activities was submitted on May 28, 1980. (13) Revisions...

40 CFR 52.1037 - Original identification of plan section.

Code of Federal Regulations, 2011 CFR

2011-07-01

... operation of new and modified major stationary sources of pollution in attainment areas. (11) Attainment... review of construction and operation of new and modified major stationary sources of pollution in non... involvement in federally funded air pollution control activities was submitted on May 28, 1980. (13) Revisions...

Integrating the Public in Mosquito Management: Active Education by Community Peers Can Lead to Significant Reduction in Peridomestic Container Mosquito Habitats

PubMed Central

Healy, Kristen; Hamilton, George; Crepeau, Taryn; Healy, Sean; Unlu, Isik; Farajollahi, Ary; Fonseca, Dina M.

2014-01-01

Mosquito species that utilize peridomestic containers for immature development are commonly aggressive human biters, and because they often reach high abundance, create significant nuisance. One of these species, the Asian tiger mosquito Aedes albopictus, is an important vector of emerging infectious diseases, such as dengue, chikungunya, and Zika fevers. Integrated mosquito management (IMM) of Ae. albopictus is particularly difficult because it requires access to private yards in urban and suburban residences. It has become apparent that in the event of a public health concern due to this species, homeowners will have to be active participants in the control process by reducing mosquito habitats in their properties, an activity known as source reduction. However, limited attempts at quantifying the effect of source reduction by homeowners have had mixed results. Of note, many mosquito control programs in the US have some form of education outreach, however the primary approach is often passive focusing on the distribution of education materials as flyers. In 2010, we evaluated the use of active community peer education in a source reduction program, using AmeriCorps volunteers. The volunteers were mobilized over a 4-week period, in two areas with approximately 1,000 residences each in urban Mercer and suburban Monmouth counties in New Jersey, USA. The volunteers were first provided training on peridomestic mosquitoes and on basic approaches to reducing the number of container habitats for mosquito larvae in backyards. Within the two treatment areas the volunteers successfully engaged 758 separate homes. Repeated measures analysis of variance showed a significant reduction in container habitats in the sites where the volunteers actively engaged the community compared to untreated control areas in both counties. Our results suggest that active education using community peer educators can be an effective means of source reduction, and a critical tool in the arsenal against peridomestic mosquitoes. PMID:25255027

Sources of Variability in Working Memory in Early Childhood: A Consideration of Age, Temperament, Language, and Brain Electrical Activity

ERIC Educational Resources Information Center

Wolfe, Christy D.; Bell, Martha Ann

2007-01-01

This study investigated age-related differences in working memory and inhibitory control (WMIC) in 3 1/2-, 4-, and 4 1/2-year-olds and how these differences were associated with differences in regulatory aspects of temperament, language comprehension, and brain electrical activity. A series of cognitive control tasks was administered to measure…

Emission Inventory Development and Application Based On an Atmospheric Emission Source Priority Control Classification Technology Method, a Case Study in the Middle Reaches of Yangtze River Urban Agglomerations, China

NASA Astrophysics Data System (ADS)

Sun, X.; Cheng, S.

2017-12-01

This paper presents the first attempt to investigate the emission source control of the Middle Reaches of Yangtze River Urban Agglomerations (MRYRUA), one of the national urban agglomerations in China. An emission inventory of the MRYRUA was the first time to be developed as inputs to the CAMx model based on county-level activity data obtained by full-coverage investigation and source-based spatial surrogates. The emission inventory was proved to be acceptable owing to the atmospheric modeling verification. A classification technology method for atmospheric pollution source priority control was the first time to be introduced and applied in the MRYRUA for the evaluation of the emission sources control on the region-scale and city-scale. MICAPS (Meteorological Information comprehensive Analysis and Processing System) was applied for the regional meteorological condition and sensitivity analysis. The results demonstrated that the emission sources in the Hefei-center Urban Agglomerations contributed biggest on the mean PM2.5 concentrations of the MRYRUA and should be taken the priority to control. The emission sources in the Ma'anshan city, Xiangtan city, Hefei city and Wuhan city were the bigger contributors on the mean PM2.5 concentrations of the MRYRUA among the cities and should be taken the priority to control. In addition, the cities along the Yangtze River and the tributary should be given the special attention for the regional air quality target attainments. This study provide a valuable preference for policy makers to develop effective air pollution control strategies.

A new topology of fuel cell hybrid power source for efficient operation and high reliability

NASA Astrophysics Data System (ADS)

Bizon, Nicu

2011-03-01

This paper analyzes a new fuel cell Hybrid Power Source (HPS) topology having the feature to mitigate the current ripple of the fuel cell inverter system. In the operation of the inverter system that is grid connected or supplies AC motors in vehicle application, the current ripple normally appears at the DC port of the fuel cell HPS. Consequently, if mitigation measures are not applied, this ripple is back propagated to the fuel cell stack. Other features of the proposed fuel cell HPS are the Maximum Power Point (MPP) tracking, high reliability in operation under sharp power pulses and improved energy efficiency in high power applications. This topology uses an inverter system directly powered from the appropriate fuel cell stack and a controlled buck current source as low power source used for ripple mitigation. The low frequency ripple mitigation is based on active control. The anti-ripple current is injected in HPS output node and this has the LF power spectrum almost the same with the inverter ripple. Consequently, the fuel cell current ripple is mitigated by the designed active control. The ripple mitigation performances are evaluated by indicators that are defined to measure the mitigation ratio of the low frequency harmonics. In this paper it is shown that good performances are obtained by using the hysteretic current control, but better if a dedicated nonlinear controller is used. Two ways to design the nonlinear control law are proposed. First is based on simulation trials that help to draw the characteristic of ripple mitigation ratio vs. fuel cell current ripple. The second is based on Fuzzy Logic Controller (FLC). The ripple factor is up to 1% in both cases.

Active Control of Inlet Noise on the JT15D Turbofan Engine

NASA Technical Reports Server (NTRS)

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

1999-01-01

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

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

Green, D.W.; Heinrich, R.R.; Graczyk, D.G.

The ACL activities covered IFR fuel reprocessing, corium-concrete interactions, environmental samples, wastes, WIPP support, Advanced Photon Source, H-Tc superconductors, EBWR vessel, soils, illegal drug detection, quality control, etc.

Radiation Protection, Safety and Security Issues in Ghana.

PubMed

Boadu, Mary; Emi-Reynolds, Geoffrey; Amoako, Joseph Kwabena; Akrobortu, Emmanuel; Hasford, Francis

2016-11-01

Although the use of radioisotopes in Ghana began in 1952, the Radiation Protection Board of Ghana was established in 1993 and served as the national competent authority for authorization and inspection of practices and activities involving radiation sources until 2015. The law has been superseded by an Act of Parliament, Act 895 of 2015, mandating the Nuclear Regulatory Authority of Ghana to take charge of the regulation of radiation sources and their applications. The Radiation Protection Institute in Ghana provided technical support to the regulatory authority. Regulatory and service activities that were undertaken by the Institute include issuance of permits for handling of a radiation sources, authorization and inspection of radiation sources, radiation safety assessment, safety assessment of cellular signal towers, and calibration of radiation-emitting equipment. Practices and activities involving application of radiation are brought under regulatory control in the country through supervision by the national competent authority.

Using high-frequency sensors to identify hydroclimatological controls on storm-event variability in catchment nutrient fluxes and source zone activation

NASA Astrophysics Data System (ADS)

Blaen, Phillip; Khamis, Kieran; Lloyd, Charlotte; Krause, Stefan

2017-04-01

At the river catchment scale, storm events can drive highly variable behaviour in nutrient and water fluxes, yet short-term dynamics are frequently missed by low resolution sampling regimes. In addition, nutrient source contributions can vary significantly within and between storm events. Our inability to identify and characterise time dynamic source zone contributions severely hampers the adequate design of land use management practices in order to control nutrient exports from agricultural landscapes. Here, we utilise an 8-month high-frequency (hourly) time series of streamflow, nitrate concentration (NO3) and fluorescent dissolved organic matter concentration (FDOM) derived from optical in-situ sensors located in a headwater agricultural catchment. We characterised variability in flow and nutrient dynamics across 29 storm events. Storm events represented 31% of the time series and contributed disproportionately to nutrient loads (43% of NO3 and 36% of CDOM) relative to their duration. Principal components analysis of potential hydroclimatological controls on nutrient fluxes demonstrated that a small number of components, representing >90% of variance in the dataset, were highly significant model predictors of inter-event variability in catchment nutrient export. Hysteresis analysis of nutrient concentration-discharge relationships suggested spatially discrete source zones existed for NO3 and FDOM, and that activation of these zones varied on an event-specific basis. Our results highlight the benefits of high-frequency in-situ monitoring for characterising complex short-term nutrient dynamics and unravelling connections between hydroclimatological variability and river nutrient export and source zone activation under extreme flow conditions. These new process-based insights are fundamental to underpinning the development of targeted management measures to reduce nutrient loading of surface waters.

Noise control using a plate radiator and an acoustic resonator

NASA Technical Reports Server (NTRS)

Pla, Frederic G. (Inventor)

1996-01-01

An active noise control subassembly for reducing noise caused by a source (such as an aircraft engine) independent of the subassembly. A noise radiating panel is bendably vibratable to generate a panel noise canceling at least a portion of the source noise. A piezoceramic actuator plate is connected to the panel. A front plate is spaced apart from the panel and the first plate, is positioned generally between the source noise and the panel, and has a sound exit port. A first pair of spaced-apart side walls each generally abut the panel and the front plate so as to generally enclose a front cavity to define a resonator.

Active control of transmission loss with smart foams.

PubMed

Kundu, Abhishek; Berry, Alain

2011-02-01

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

Active Control Of Structure-Borne Noise

NASA Astrophysics Data System (ADS)

Elliott, S. J.

1994-11-01

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

Active Control of Fan Noise: Feasibility Study. Volume 3; Active Fan Noise Cancellation in the NASA Lewis Active Noise Control Fan Facility

NASA Technical Reports Server (NTRS)

Pla, Frederic G.; Hu, Ziqiang; Sutliff, Daniel L.

1996-01-01

This report describes the Active Noise Cancellation (ANC) System designed by General Electric and tested in the NASA Lewis Research Center's (LERC) 48 inch Active Noise Control Fan (ANCF). The goal of this study is to assess the feasibility of using wall mounted secondary acoustic sources and sensors within the duct of a high bypass turbofan aircraft engine for global active noise cancellation of fan tones. The GE ANC system is based on a modal control approach. A known acoustic mode propagating in the fan duct is canceled using an array of flush-mounted compact sound sources. The canceling modal signal is generated by a modal controller. Inputs to the controller are signals from a shaft encoder and from a microphone array which senses the residual acoustic mode in the duct. The key results are that the (6,0) was completely eliminated at the 920 Hz design frequency and substantially reduced elsewhere. The total tone power was reduced 6.8 dB (out of a possible 9.8 dB). Farfield reductions of 15 dB (SPL) were obtained. The (4,0) and (4,1) modes were reduced simultaneously yielding a 15 dB PWL decrease. The results indicate that global attenuation of PWL at the target frequency was obtained in the aft quadrant using an ANC actuator and sensor system totally contained within the duct. The quality of the results depended on precise mode generation. High spillover into spurious modes generated by the ANC actuator array caused less than optimum levels of PWL reduction. The variation in spillover is believed to be due to calibration procedure, but must be confirmed in subsequent tests.

Brain Areas Controlling Heart Rate Variability in Tinnitus and Tinnitus-Related Distress

PubMed Central

Vanneste, Sven; De Ridder, Dirk

2013-01-01

Background Tinnitus is defined as an intrinsic sound perception that cannot be attributed to an external sound source. Distress in tinnitus patients is related to increased beta activity in the dorsal part of the anterior cingulate and the amount of distress correlates with network activity consisting of the amygdala-anterior cingulate cortex-insula-parahippocampus. Previous research also revealed that distress is associated to a higher sympathetic (OS) tone in tinnitus patients and tinnitus suppression to increased parasympathetic (PS) tone. Methodology The aim of the present study is to investigate the relationship between tinnitus distress and the autonomic nervous system and find out which cortical areas are involved in the autonomic nervous system influences in tinnitus distress by the use of source localized resting state electroencephalogram (EEG) recordings and electrocardiogram (ECG). Twenty-one tinnitus patients were included in this study. Conclusions The results indicate that the dorsal and subgenual anterior cingulate, as well as the left and right insula are important in the central control of heart rate variability in tinnitus patients. Whereas the sympathovagal balance is controlled by the subgenual and pregenual anterior cingulate cortex, the right insula controls sympathetic activity and the left insula the parasympathetic activity. The perceived distress in tinnitus patients seems to be sympathetically mediated. PMID:23533644

Multi-frequency localization of aberrant brain activity in autism spectrum disorder.

PubMed

Xiang, Jing; Korostenskaja, Milena; Molloy, Cynthia; deGrauw, Xinyao; Leiken, Kimberly; Gilman, Carley; Meinzen-Derr, Jareen; Fujiwara, Hisako; Rose, Douglas F; Mitchell, Terry; Murray, Donna S

2016-01-01

The abnormality of intrinsic brain activity in autism spectrum disorders (ASDs) is still inconclusive. Contradictory results have been found pointing towards hyper-activity or hypo-activity in various brain regions. The present research aims to investigate the spatial and spectral signatures of aberrant brain activity in an unprecedented frequency range of 1-2884 Hz at source levels in ASD using newly developed methods. Seven ASD subjects and age- and gender-matched controls were studied using a high-sampling rate magnetoencephalography (MEG) system. Brain activity in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), low gamma (30-55 Hz), high gamma (65-90 Hz), ripples (90-200 Hz), high-frequency oscillations (HFOs, 200-1000 Hz), and very high-frequency oscillations (VHFOs, 1000-2884 Hz) was volumetrically localized and measured using wavelet and beamforming. In comparison to controls, ASD subjects had significantly higher odds of alpha activity (8-12 Hz) in the sensorimotor cortex (mu rhythm), and generally high-frequency activity (90-2884 Hz) in the frontal cortex. The source power of HFOs (200-1000 Hz) in the frontal cortex in ASD was significantly elevated as compared with controls. The results suggest that ASD has significantly altered intrinsic brain activity in both low- and high-frequency ranges. Increased intrinsic high-frequency activity in the frontal cortex may play a key role in ASD. Copyright © 2015 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Phytochemical screening and in vitro bioactivities of the extracts of aerial part of Boerhavia diffusa Linn.

PubMed

Apu, Apurba Sarker; Liza, Mahmuda Sultana; Jamaluddin, A T M; Howlader, Md Amran; Saha, Repon Kumer; Rizwan, Farhana; Nasrin, Nishat

2012-09-01

To investigate the bioactivities of crude n-hexane, ethyl acetate and methanol extracts of aerial part of Boerhavia diffusa Linn. (B. diffusa) and its phytochemical analysis. The identification of phytoconstituents and assay of antioxidant, thrombolytic, cytotoxic, antimicrobial activities were conducted using specific standard in vitro procedures. The results showed that the plant extracts were a rich source of phytoconstituents. Methanol extract showed higher antioxidant, thrombolytic activity and less cytotoxic activity than those of n-hexane and ethyl acetate extracts of B. diffusa. Among the bioactivities, antioxidant activity was the most notable compared to the positive control and thus could be a potential rich source of natural antioxidant. In case of antimicrobial screening, crude extracts of the plant showed remarkable antibacterial activity against tested microorganisms. All the extracts showed significant inhibitory activity against Candida albicuns, at a concentration of 1000 µg/disc. The present findings suggest that, the plant widely available in Bangladesh, could be a prominent source of medicinally important natural compounds.

Modeling of influencing parameters in active noise control on an enclosure wall

NASA Astrophysics Data System (ADS)

Tarabini, Marco; Roure, Alain

2008-04-01

This paper investigates, by means of a numerical model, the possibility of using an active noise barrier to virtually reduce the acoustic transparency of a partition wall inside an enclosure. The room is modeled with the image method as a rectangular enclosure with a stationary point source; the active barrier is set up by an array of loudspeakers and error microphones and is meant to minimize the squared sound pressure on a wall with the use of a decentralized control. Simulations investigate the effects of the enclosure characteristics and of the barrier geometric parameters on the sound pressure attenuation on the controlled partition, on the whole enclosure potential energy and on the diagonal control stability. Performances are analyzed in a frequency range of 25-300 Hz at discrete 25 Hz steps. Influencing parameters and their effects on the system performances are identified with a statistical inference procedure. Simulation results have shown that it is possible to averagely reduce the sound pressure on the controlled partition. In the investigated configuration, the surface attenuation and the diagonal control stability are mainly driven by the distance between the loudspeakers and the error microphones and by the loudspeakers directivity; minor effects are due to the distance between the error microphones and the wall, by the wall reflectivity and by the active barrier grid meshing. Room dimensions and source position have negligible effects. Experimental results point out the validity of the model and the efficiency of the barrier in the reduction of the wall acoustic transparency.

Active noise control using noise source having adaptive resonant frequency tuning through variable ring loading

NASA Technical Reports Server (NTRS)

Rajiyah, Harindra (Inventor); Pla, Frederic G. (Inventor); Hedeen, Robert A. (Inventor); Renshaw, Anthony A. (Inventor)

1995-01-01

A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of noise radiating structure is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating structure is tuned by a plurality of drivers arranged to contact the noise radiating structure. Excitation of the drivers causes expansion or contraction of the drivers, thereby varying the edge loading applied to the noise radiating structure. The drivers are actuated by a controller which receives input of a feedback signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the drivers, causing them to expand or contract. The noise radiating structure may be either the outer shroud of the engine or a ring mounted flush with an inner wall of the shroud or disposed in the interior of the shroud.

Active noise control using noise source having adaptive resonant frequency tuning through stress variation

NASA Technical Reports Server (NTRS)

Pla, Frederic G. (Inventor); Renshaw, Anthony A. (Inventor); Rajiyah, Harindra (Inventor); Hedeen, Robert A. (Inventor)

1995-01-01

A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of a noise radiating element is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating element is tuned by an expandable ring embedded in the noise radiating element. Excitation of the ring causes expansion or contraction of the ring, thereby varying the stress in the noise radiating element. The ring is actuated by a controller which receives input of a feedback signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the ring, causing the ring to expand or contract. Instead of a single ring embedded in the noise radiating panel, a first expandable ring can be bonded to one side of the noise radiating element, and a second expandable ring can be bonded to the other side.

A new dust source map of Central Asia derived from MODIS Terra/Aqua data using dust enhancement techniques

NASA Astrophysics Data System (ADS)

Nobakht, Mohamad; Shahgedanova, Maria; White, Kevin

2017-04-01

Central Asian deserts are a significant source of dust in the middle latitudes, where economic activity and health of millions of people are affected by dust storms. Detailed knowledge of sources of dust, controls over their activity, seasonality and atmospheric pathways are of crucial importance but to date, these data are limited. This paper presents a detailed database of sources of dust emissions in Central Asia, from western China to the Caspian Sea, obtained from the analysis of the Moderate Resolution Imaging Spectroradiometer (MODIS) data between 2003 and 2012. A dust enhancement algorithm was employed to obtain two composite images per day at 1 km resolution from MODIS Terra/Aqua acquisitions, from which dust point sources (DPS) were detected by visual analysis and recorded in a database together with meteorological variables at each DPS location. Spatial analysis of DPS has revealed several active source regions, including some which were not widely discussed in literature before (e.g. Northern Afghanistan sources, Betpak-Dala region in western Kazakhstan). Investigation of land surface characteristics and meteorological conditions at each source region revealed mechanisms for the formation of dust sources, including post-fire wind erosion (e.g. Lake Balkhash basin) and rapid desertification (e.g. the Aral Sea). Different seasonal patterns of dust emissions were observed as well as inter-annual trends. The most notable feature was an increase in dust activity in the Aral Kum.

Active wavefront control challenges of the NASA Large Deployable Reflector (LDR)

NASA Technical Reports Server (NTRS)

Meinel, Aden B.; Meinel, Marjorie P.; Manhart, Paul K.; Hochberg, Eric B.

1989-01-01

The 20-m Large Deployable Reflector will have a segmented primary mirror. Achieving diffraction-limited performance at 50 microns requires correction for the errors of tilt and piston of the primary mirror. This correction can be obtained in two ways, the use of an active primary or a correction at a demagnified pupil of the primary. A critical requirement is the means for measurement of the wavefront error and maintaining phasing during the observation of objects that may be too faint for determining the error. Absolute phasing can only be determined using a cooperative source. Maintenance of phasing can be done with an on-board source. A number of options are being explored as discussed below. The many issues concerning the assessment and control of an active segmented mirror will be addressed with an early construction of the Precision Segmented Reflector testbed.

Active wavefront control challenges of the NASA Large Deployable Reflector (LDR)

NASA Astrophysics Data System (ADS)

Meinel, Aden B.; Meinel, Marjorie P.; Manhart, Paul K.; Hochberg, Eric B.

1989-09-01

The 20-m Large Deployable Reflector will have a segmented primary mirror. Achieving diffraction-limited performance at 50 microns requires correction for the errors of tilt and piston of the primary mirror. This correction can be obtained in two ways, the use of an active primary or a correction at a demagnified pupil of the primary. A critical requirement is the means for measurement of the wavefront error and maintaining phasing during the observation of objects that may be too faint for determining the error. Absolute phasing can only be determined using a cooperative source. Maintenance of phasing can be done with an on-board source. A number of options are being explored as discussed below. The many issues concerning the assessment and control of an active segmented mirror will be addressed with an early construction of the Precision Segmented Reflector testbed.

Cancelation and its simulation using Matlab according to active noise control case study of automotive noise silencer

NASA Astrophysics Data System (ADS)

Alfisyahrin; Isranuri, I.

2018-02-01

Active Noise Control is a technique to overcome noisy with noise or sound countered with sound in scientific terminology i.e signal countered with signals. This technique can be used to dampen relevant noise in accordance with the wishes of the engineering task and reducing automotive muffler noise to a minimum. Objective of this study is to develop a Active Noise Control which should cancel the noise of automotive Exhaust (Silencer) through Signal Processing Simulation methods. Noise generator of Active Noise Control is to make the opponent signal amplitude and frequency of the automotive noise. The steps are: Firstly, the noise of automotive silencer was measured to characterize the automotive noise that its amplitude and frequency which intended to be expressed. The opposed sound which having similar character with the signal source should be generated by signal function. A comparison between the data which has been completed with simulation calculations Fourier transform field data is data that has been captured on the muffler (noise silencer) Toyota Kijang Capsule assembly 2009. MATLAB is used to simulate how the signal processing noise generated by exhaust (silencer) using FFT. This opponent is inverted phase signal from the signal source 180° conducted by Instruments of Signal Noise Generators. The process of noise cancelation examined through simulation using computer software simulation. The result is obtained that attenuation of sound (noise cancellation) has a difference of 33.7%. This value is obtained from the comparison of the value of the signal source and the signal value of the opponent. So it can be concluded that the noisy signal can be attenuated by 33.7%.

Real Time Digital Control of a Magnetostrictive Actuator

NASA Technical Reports Server (NTRS)

Zrostlik, Rick L.; Hall, David L.; Flatau, Alison B.

1996-01-01

The use of the magnetostrictive material Terfenol-D as a motion source in active vibration control (AVC) systems are being studied. Currently it is of limited use due to the nonlinear nature of the strain versus magnetization curve and the magnetic hysteresis in the Terfenol-D. One manifestation of these nonlinearities is waveform distortion in the output velocity of the transducer. For Terfenol-D to be used in ever greater numbers of AVC systems, these nonlinearities must be addressed. In this study the nonlinearities are treated as disturbances to a linear system. The acceleration output is used in simple analog and digital feedback control schemes to improve linearity of the transducer. In addition, the use of a Terfenol-D actuator in an AVC system is verified. Both analog and digital controllers are implemented and results compared. A cantilever beam system is considered for AVC applications. The second thrust of this presentation is the reduction of harmonic distortions. Two conclusions can be reached from this work. One, the linearization of Terfenol-D transducers is possible with the use of feedback controllers, both digital and analog. Second, Terfenol-D is a viable motion source in active vibration control systems utilizing either analog or digital controllers.

Active control of turbulent boundary layer-induced sound transmission through the cavity-backed double panels

NASA Astrophysics Data System (ADS)

Caiazzo, A.; Alujević, N.; Pluymers, B.; Desmet, W.

2018-05-01

This paper presents a theoretical study of active control of turbulent boundary layer (TBL) induced sound transmission through the cavity-backed double panels. The aerodynamic model used is based on the Corcos wall pressure distribution. The structural-acoustic model encompasses a source panel (skin panel), coupled through an acoustic cavity to the radiating panel (trim panel). The radiating panel is backed by a larger acoustic enclosure (the back cavity). A feedback control unit is located inside the acoustic cavity between the two panels. It consists of a control force actuator and a sensor mounted at the actuator footprint on the radiating panel. The control actuator can react off the source panel. It is driven by an amplified velocity signal measured by the sensor. A fully coupled analytical structural-acoustic model is developed to study the effects of the active control on the sound transmission into the back cavity. The stability and performance of the active control system are firstly studied on a reduced order model. In the reduced order model only two fundamental modes of the fully coupled system are assumed. Secondly, a full order model is considered with a number of modes large enough to yield accurate simulation results up to 1000 Hz. It is shown that convincing reductions of the TBL-induced vibrations of the radiating panel and the sound pressure inside the back cavity can be expected. The reductions are more pronounced for a certain class of systems, which is characterised by the fundamental natural frequency of the skin panel larger than the fundamental natural frequency of the trim panel.

Microbial cell-free extracts as sources of enzyme activities to be used for enhancement flavor development of ewe milk cheese.

PubMed

Calasso, Maria; Mancini, Leonardo; Di Cagno, Raffaella; Cardinali, Gianluigi; Gobbetti, Marco

2015-09-01

Freeze-dried cell-free extracts (CFE) from Lactobacillus casei LC01, Weissella cibaria 1XF5, Hafnia alvei Moller ATCC 51815, and Debaryomyces hansenii LCF-558 were used as sources of enzyme activities for conditioning the ripening of ewe milk cheese. Compared with control cheese (CC), CFE did not affect the gross composition and the growth of the main microbial groups of the cheeses. As shown through urea-PAGE electrophoresis of the pH 4.6-soluble nitrogen fraction and the analysis of free AA, the secondary proteolysis of the cheeses with CFE added was markedly differed from that of the CC. Compared with CC, several enzyme activities were higher in the water-soluble extracts from cheeses made with CFE. In agreement, the levels of 49 volatile compounds significantly differentiated CC from the cheeses made with CFE. The level of some alcohols, ketones, sulfur compounds, and furans were the lowest in the CC, whereas most aldehydes were the highest. Each CFE seemed to affect a specific class of chemical compounds (e.g., the CFE from H. alvei ATCC 51815 mainly influenced the synthesis of sulfur compounds). Apart from the microbial source used, the cheeses with the addition of CFE showed higher score for acceptability than the control cheese. Cheese ripening was accelerated or conditioned using CFE as sources of tailored enzyme activities. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Examination of Incubation Conditions for Production of HERICIUM ERINACEUM

NASA Astrophysics Data System (ADS)

Okumura, Ryosuke; Sasaki, Chizuru; Asada, Chikako; Nakamura, Yoshitoshi

Basidiomycetes has recently attracted considerable attention for its various physiological activities, such as antitumor, antioxidant and immunostimulating activities. Compounds isolated from fruit body of Hericium erinaceum, commonly called Yamabushitake in Japan, have interesting biological activities such as cytotoxic effectors on cancer cell (HeLa cells) and stimulators of synthesis of nerve growth factor. It is necessary for the cultivation of the fruit body of mushroom to control light, temperature, humidity. Otherwise, mycelia cultivation needs only temperature control. H. erinaceum cultivated by submerged culture have similar physiological activities to the fruit body of H. erinaceum, which suggests cultured mycelia can potentially become a promoter of synthesis of nerve growth factor. In this study, we used whey which is by-products of cheese-making process as an alternative nitrogen source in submerged cultivation of H. erinaceum mycelia, and then dry cell weight (DCW) and DCW productivity of whey medium were compared with those of chemical nutrient medium. When whey was used as a nitrogen source, DCW and DCW productivity are 1.5 times higher than those of chemical nutrient medium, 5.99 g/L and 0.60 g/L/day, respectively. It was suggested that whey could be used as an alternative nitrogen source and a growth promoting factor in H. erinaceum mycelia cultivation.

A nitrogen response pathway regulates virulence functions in Fusarium oxysporum via the protein kinase TOR and the bZIP protein MeaB.

PubMed

López-Berges, Manuel S; Rispail, Nicolas; Prados-Rosales, Rafael C; Di Pietro, Antonio

2010-07-01

During infection, fungal pathogens activate virulence mechanisms, such as host adhesion, penetration and invasive growth. In the vascular wilt fungus Fusarium oxysporum, the mitogen-activated protein kinase Fmk1 is required for plant infection and controls processes such as cellophane penetration, vegetative hyphal fusion, or root adhesion. Here, we show that these virulence-related functions are repressed by the preferred nitrogen source ammonium and restored by treatment with l-methionine sulfoximine or rapamycin, two specific inhibitors of Gln synthetase and the protein kinase TOR, respectively. Deletion of the bZIP protein MeaB also resulted in nitrogen source-independent activation of virulence mechanisms. Activation of these functions did not require the global nitrogen regulator AreA, suggesting that MeaB-mediated repression of virulence functions does not act through inhibition of AreA. Tomato plants (Solanum lycopersicum) supplied with ammonium rather than nitrate showed a significant reduction in vascular wilt symptoms when infected with the wild type but not with the DeltameaB strain. Nitrogen source also affected invasive growth in the rice blast fungus Magnaporthe oryzae and the wheat head blight pathogen Fusarium graminearum. We propose that a conserved nitrogen-responsive pathway might operate via TOR and MeaB to control virulence in plant pathogenic fungi.

Age-related differences in agenda-driven monitoring of format and task information

PubMed Central

Mitchell, Karen J.; Ankudowich, Elizabeth; Durbin, Kelly A.; Greene, Erich J.; Johnson, Marcia K.

2013-01-01

Age-related source memory deficits may arise, in part, from changes in the agenda-driven processes that control what features of events are relevant during remembering. Using fMRI, we compared young and older adults on tests assessing source memory for format (picture, word) or encoding task (self-, other-referential), as well as on old-new recognition. Behaviorally, relative to old-new recognition, older adults showed disproportionate and equivalent deficits on both source tests compared to young adults. At encoding, both age groups showed expected activation associated with format in posterior visual processing areas, and with task in medial prefrontal cortex. At test, the groups showed similar selective, agenda-related activity in these representational areas. There were, however, marked age differences in the activity of control regions in lateral and medial prefrontal cortex and lateral parietal cortex. Results of correlation analyses were consistent with the idea that young adults had greater trial-by-trial agenda-driven modulation of activity (i.e., greater selectivity) than did older adults in representational regions. Thus, under selective remembering conditions where older adults showed clear differential regional activity in representational areas depending on type of test, they also showed evidence of disrupted frontal and parietal function and reduced item-by-item modulation of test-appropriate features. This pattern of results is consistent with an age-related deficit in the engagement of selective reflective attention. PMID:23357375

Increased Error-Related Negativity (ERN) in Childhood Anxiety Disorders: ERP and Source Localization

ERIC Educational Resources Information Center

Ladouceur, Cecile D.; Dahl, Ronald E.; Birmaher, Boris; Axelson, David A.; Ryan, Neal D.

2006-01-01

Background: In this study we used event-related potentials (ERPs) and source localization analyses to track the time course of neural activity underlying response monitoring in children diagnosed with an anxiety disorder compared to age-matched low-risk normal controls. Methods: High-density ERPs were examined following errors on a flanker task…

Resident bacteria of plums and their potential for controlling brown rot after harvest

USDA-ARS?s Scientific Manuscript database

Fruit microflora has been the richest source of antagonists against fruit decays and the active ingredient in all currently available commercial biocontrol products. A comprehensive evaluation of plum bacteria for biocontrol activity against Monilinia fructicola, causing brown rot of stone fruit, w...

40 CFR 50.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... air quality, is not reasonably controllable or preventable, is an event caused by human activity that... precipitation, or air pollution relating to source noncompliance. (k) Natural event means an event in which human activity plays little or no direct causal role. (l) Exceedance with respect to a national ambient...

40 CFR 50.1 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... air quality, is not reasonably controllable or preventable, is an event caused by human activity that... precipitation, or air pollution relating to source noncompliance. (k) Natural event means an event in which human activity plays little or no direct causal role. (l) Exceedance with respect to a national ambient...

40 CFR 50.1 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... air quality, is not reasonably controllable or preventable, is an event caused by human activity that... precipitation, or air pollution relating to source noncompliance. (k) Natural event means an event in which human activity plays little or no direct causal role. (l) Exceedance with respect to a national ambient...

40 CFR 50.1 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... air quality, is not reasonably controllable or preventable, is an event caused by human activity that... precipitation, or air pollution relating to source noncompliance. (k) Natural event means an event in which human activity plays little or no direct causal role. (l) Exceedance with respect to a national ambient...

40 CFR 50.1 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... air quality, is not reasonably controllable or preventable, is an event caused by human activity that... precipitation, or air pollution relating to source noncompliance. (k) Natural event means an event in which human activity plays little or no direct causal role. (l) Exceedance with respect to a national ambient...

Enhanced Early Neuronal Processing of Food Pictures in Anorexia Nervosa: A Magnetoencephalography Study

PubMed Central

Scaife, Jessica C.; Park, Rebecca J.

2016-01-01

Neuroimaging studies in Anorexia Nervosa (AN) have shown increased activation in reward and cognitive control regions in response to food, and a behavioral attentional bias (AB) towards food stimuli is reported. This study aimed to further investigate the neural processing of food using magnetoencephalography (MEG). Participants were 13 females with restricting-type AN, 14 females recovered from restricting-type AN, and 15 female healthy controls. MEG data was acquired whilst participants viewed high- and low-calorie food pictures. Attention was assessed with a reaction time task and eye tracking. Time-series analysis suggested increased neural activity in response to both calorie conditions in the AN groups, consistent with an early AB. Increased activity was observed at 150 ms in the current AN group. Neuronal activity at this latency was at normal level in the recovered group; however, this group exhibited enhanced activity at 320 ms after stimulus. Consistent with previous studies, analysis in source space and behavioral data suggested enhanced attention and cognitive control processes in response to food stimuli in AN. This may enable avoidance of salient food stimuli and maintenance of dietary restraint in AN. A later latency of increased activity in the recovered group may reflect a reversal of this avoidance, with source space and behavioral data indicating increased visual and cognitive processing of food stimuli. PMID:27525258

In vitro and In vivo Postprandial Glycemic Activity of Citrus limetta Peel Flour

PubMed Central

Flores-Fernández, José Miguel; Barragán-Álvarez, Carla Patricia; Díaz-Martínez, Nestor Emmanuel; Villanueva-Rodríguez, Socorro; Padilla-Camberos, Eduardo

2017-01-01

Background: Previous studies of Citrus spp. peel have shown hypoglycemic and antioxidant activities. Citrus limetta has been studied for its therapeutic properties. Diabetes mellitus (DM) is a health problem in Mexico and worldwide, that takes a vital importance due to its high incidence. Recently, scientists have searched natural sources to control the disease. Materials and Methods: In this study, we evaluated the in vitro hypoglycemic activity and in vivo postprandial glycemic effect of C. limetta peel flour by glucose adsorption and retardation assays as well as postprandial serum glucose levels using a group of female Balb-c mice, respectively. Results: C. limetta peel flour showed a glucose adsorption capacity of 16.58 mM, having a similar effect regarding the positive control. The glucose diffusion in the dialysate was elevated, with a glucose dialysis retardation index of 33.79% in a period of 3 h, showing similar results to positive control. Postprandial serum glucose levels in the animal group treated with C. limetta peel flour showed a glucose level of 41.4 mg/dL, being this value significantly lower than negative control group and similar to positive control. Toxicity tests showed good tolerance to the dose of 2000 mg/kg. Conclusion: C. limetta peel flour could act as a source of functional compounds for the control of DM. SUMMARY Citrus limetta peel flour showed a glucose adsorption capacity similar to the positive controlThe glucose diffusion in the dialysate was elevated, showing similar results to positive controlPostprandial serum glucose levels in the animal group treated with C. limetta peel flour showed a glucose level significantly lower than negative control group and similar to positive controlToxicity tests showed good toleranceC. limetta peel flour could act as a source of functional compounds for the control of diabetes mellitus. Abbreviations used: CIATEJ: Center for Research and Assistance in Technology and Design of Jalisco; DM: Diabetes mellitus; FGC: Final glucose concentration; GDRI: Glucose dialysis retardation index; IGC: Initial glucose concentration; OECD: Organization for Economic Cooperation and Development. PMID:29200722

α-Amylase inhibitors: a review of raw material and isolated compounds from plant source.

PubMed

Sales, Paloma Michelle; Souza, Paula Monteiro; Simeoni, Luiz Alberto; Silveira, Damaris

2012-01-01

Inhibition of α-amylase, enzyme that plays a role in digestion of starch and glycogen, is considered a strategy for the treatment of disorders in carbohydrate uptake, such as diabetes and obesity, as well as, dental caries and periodontal diseases. Plants are an important source of chemical constituents with potential for inhibition of α-amylase and can be used as therapeutic or functional food sources. A review about crude extracts and isolated compounds from plant source that have been tested for α-amylase inhibitory activity has been done. The analysis of the results shows a variety of crude extracts that present α-amylase inhibitory activity and some of them had relevant activity when compared with controls used in the studies. Amongst the phyto-constituents that have been investigated, flavonoids are one of them that demonstrated the highest inhibitory activities with the potential of inhibition related to number of hydroxyl groups in the molecule of the compound. Several phyto-constituents and plant species as α-amylase inhibitors are being reported in this article. Majority of studies have focused on the anti-amylase phenolic compounds.

Descriptive Social Norms as Underappreciated Sources of Social Control

ERIC Educational Resources Information Center

Cialdini, Robert B.

2007-01-01

Bockenholt and van der Heijden's results regarding compliance with insurance regulations--that the enforcement activities of a regulatory agency were relatively unpredictive of compliance--are consistent with findings from other domains (e.g., tax adherence), where personal factors and informal social controls have been shown to play a more…

Adaptive powertrain control for plugin hybrid electric vehicles

DOEpatents

Kedar-Dongarkar, Gurunath; Weslati, Feisel

2013-10-15

A powertrain control system for a plugin hybrid electric vehicle. The system comprises an adaptive charge sustaining controller; at least one internal data source connected to the adaptive charge sustaining controller; and a memory connected to the adaptive charge sustaining controller for storing data generated by the at least one internal data source. The adaptive charge sustaining controller is operable to select an operating mode of the vehicle's powertrain along a given route based on programming generated from data stored in the memory associated with that route. Further described is a method of adaptively controlling operation of a plugin hybrid electric vehicle powertrain comprising identifying a route being traveled, activating stored adaptive charge sustaining mode programming for the identified route and controlling operation of the powertrain along the identified route by selecting from a plurality of operational modes based on the stored adaptive charge sustaining mode programming.

Integrity of central nervous function in diabetes mellitus assessed by resting state EEG frequency analysis and source localization.

PubMed

Frøkjær, Jens B; Graversen, Carina; Brock, Christina; Khodayari-Rostamabad, Ahmad; Olesen, Søren S; Hansen, Tine M; Søfteland, Eirik; Simrén, Magnus; Drewes, Asbjørn M

2017-02-01

Diabetes mellitus (DM) is associated with structural and functional changes of the central nervous system. We used electroencephalography (EEG) to assess resting state cortical activity and explored associations to relevant clinical features. Multichannel resting state EEG was recorded in 27 healthy controls and 24 patients with longstanding DM and signs of autonomic dysfunction. The power distribution based on wavelet analysis was summarized into frequency bands with corresponding topographic mapping. Source localization analysis was applied to explore the electrical cortical sources underlying the EEG. Compared to controls, DM patients had an overall decreased EEG power in the delta (1-4Hz) and gamma (30-45Hz) bands. Topographic analysis revealed that these changes were confined to the frontal region for the delta band and to central cortical areas for the gamma band. Source localization analysis identified sources with reduced activity in the left postcentral gyrus for the gamma band and in right superior parietal lobule for the alpha1 (8-10Hz) band. DM patients with clinical signs of autonomic dysfunction and gastrointestinal symptoms had evidence of altered resting state cortical processing. This may reflect metabolic, vascular or neuronal changes associated with diabetes. Copyright © 2017 Elsevier Inc. All rights reserved.

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

NASA Astrophysics Data System (ADS)

Ho, Jen-Hsuan; Berkhoff, Arthur

2014-03-01

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

Culturable bacteria from plum fruit surfaces and their potential for controlling brown rot after harvest

USDA-ARS?s Scientific Manuscript database

Fruit microflora has been the richest source of antagonists against fruit decays and the active ingredient in all currently available commercial biocontrol products. A comprehensive evaluation of plum bacteria for biocontrol activity against Monilinia fructicola, causing brown rot of stone fruit, w...

Tug fleet and ground operations schedules and controls. Volume 2: part 2, addenda

NASA Technical Reports Server (NTRS)

1975-01-01

The results of a study to assess the tug safing requirements at postlanding are presented. The study considered the normal (green light) conditions from orbiter landing to completion of preparations for the next launch. Normal tug ground turnaround operations include handling and transportation activities and the performance of inspections, tests, and checkout functions. These activities dictate that hazards to ground personnel, the tug, GSE, facilities, and ecology be reduced to the lowest practical level consistent with program objectives, cost, and schedules. During flight operations, the tug contains energy sources that constitute potential hazards but are required for mission accomplishment. These potential hazards have been reduced to an acceptable level for flight operation by design features and by providing for control of energy sources.

The Crc protein inhibits the production of polyhydroxyalkanoates in Pseudomonas putida under balanced carbon/nitrogen growth conditions.

PubMed

La Rosa, Ruggero; de la Peña, Fernando; Prieto, María Axiliadora; Rojo, Fernando

2014-01-01

Pseudomonas putida synthesizes polyhydroxyalkanoates (PHAs) as storage compounds. PHA synthesis is more active when the carbon source is in excess and the nitrogen source is limiting, but can also occur at a lower rate under balanced carbon/nitrogen ratios. This work shows that PHA synthesis is controlled by the Crc global regulator, a protein that optimizes carbon metabolism by inhibiting the expression of genes involved in the use of non-preferred carbon sources. Crc acts post-transcriptionally. The mRNAs of target genes contain characteristic catabolite activity (CA) motifs near the ribosome binding site. Sequences resembling CA motifs can be predicted for the phaC1 gene, which codes for a PHA polymerase, and for phaI and phaF, which encode proteins associated to PHA granules. Our results show that Crc inhibits the translation of phaC1 mRNA, but not that of phaI or phaF, reducing the amount of PHA accumulated in the cell. Crc inhibited PHA synthesis during exponential growth in media containing a balanced carbon/nitrogen ratio. No inhibition was seen when the carbon/nitrogen ratio was imbalanced. This extends the role of Crc beyond that of controlling the hierarchical utilization of carbon sources and provides a link between PHA synthesis and the global regulatory networks controlling carbon flow. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

Producing data-based sensitivity kernels from convolution and correlation in exploration geophysics.

NASA Astrophysics Data System (ADS)

Chmiel, M. J.; Roux, P.; Herrmann, P.; Rondeleux, B.

2016-12-01

Many studies have shown that seismic interferometry can be used to estimate surface wave arrivals by correlation of seismic signals recorded at a pair of locations. In the case of ambient noise sources, the convergence towards the surface wave Green's functions is obtained with the criterion of equipartitioned energy. However, seismic acquisition with active, controlled sources gives more possibilities when it comes to interferometry. The use of controlled sources makes it possible to recover the surface wave Green's function between two points using either correlation or convolution. We investigate the convolutional and correlational approaches using land active-seismic data from exploration geophysics. The data were recorded on 10,710 vertical receivers using 51,808 sources (seismic vibrator trucks). The sources spacing is the same in both X and Y directions (30 m) which is known as a "carpet shooting". The receivers are placed in parallel lines with a spacing 150 m in the X direction and 30 m in the Y direction. Invoking spatial reciprocity between sources and receivers, correlation and convolution functions can thus be constructed between either pairs of receivers or pairs of sources. Benefiting from the dense acquisition, we extract sensitivity kernels from correlation and convolution measurements of the seismic data. These sensitivity kernels are subsequently used to produce phase-velocity dispersion curves between two points and to separate the higher mode from the fundamental mode for surface waves. Potential application to surface wave cancellation is also envisaged.

Regional Patterns of Elevated Alpha and High-Frequency Electroencephalographic Activity during Nonrapid Eye Movement Sleep in Chronic Insomnia: A Pilot Study.

PubMed

Riedner, Brady A; Goldstein, Michael R; Plante, David T; Rumble, Meredith E; Ferrarelli, Fabio; Tononi, Giulio; Benca, Ruth M

2016-04-01

To examine nonrapid eye movement (NREM) sleep in insomnia using high-density electroencephalography (EEG). All-night sleep recordings with 256 channel high-density EEG were analyzed for 8 insomnia subjects (5 females) and 8 sex and age-matched controls without sleep complaints. Spectral analyses were conducted using unpaired t-tests and topographical differences between groups were assessed using statistical non-parametric mapping. Five minute segments of deep NREM sleep were further analyzed using sLORETA cortical source imaging. The initial topographic analysis of all-night NREM sleep EEG revealed that insomnia subjects had more high-frequency EEG activity (> 16 Hz) compared to good sleeping controls and that the difference between groups was widespread across the scalp. In addition, the analysis also showed that there was a more circumscribed difference in theta (4-8 Hz) and alpha (8-12 Hz) power bands between groups. When deep NREM sleep (N3) was examined separately, the high-frequency difference between groups diminished, whereas the higher regional alpha activity in insomnia subjects persisted. Source imaging analysis demonstrated that sensory and sensorimotor cortical areas consistently exhibited elevated levels of alpha activity during deep NREM sleep in insomnia subjects relative to good sleeping controls. These results suggest that even during the deepest stage of sleep, sensory and sensorimotor areas in insomnia subjects may still be relatively active compared to control subjects and to the rest of the sleeping brain. © 2016 Associated Professional Sleep Societies, LLC.

Beta activity in the premotor cortex is increased during stabilized as compared to normal walking

PubMed Central

Bruijn, Sjoerd M.; Van Dieën, Jaap H.; Daffertshofer, Andreas

2015-01-01

Walking on two legs is inherently unstable. Still, we humans perform remarkable well at it, mostly without falling. To gain more understanding of the role of the brain in controlling gait stability we measured brain activity using electro-encephalography (EEG) during stabilized and normal walking. Subjects walked on a treadmill in two conditions, each lasting 10 min; normal, and while being laterally stabilized by elastic cords. Kinematics of trunk and feet, electro-myography (EMG) of neck muscles, as well as 64-channel EEG were recorded. To assess gait stability the local divergence exponent, step width, and trunk range of motion were calculated from the kinematic data. We used independent component (IC) analysis to remove movement, EMG, and eyeblink artifacts from the EEG, after which dynamic imaging of coherent sources beamformers were determined to identify cortical sources that showed a significant difference between conditions. Stabilized walking led to a significant increase in gait stability, i.e., lower local divergence exponents. Beamforming analysis of the beta band activity revealed significant sources in bilateral pre-motor cortices. Projection of sensor data on these sources showed a significant difference only in the left premotor area, with higher beta power during stabilized walking, specifically around push-off, although only significant around contralateral push-off. It appears that even during steady gait the cortex is involved in the control of stability. PMID:26578937

Impact of head models in N170 component source imaging: results in control subjects and ADHD patients

NASA Astrophysics Data System (ADS)

Beltrachini, L.; Blenkmann, A.; von Ellenrieder, N.; Petroni, A.; Urquina, H.; Manes, F.; Ibáñez, A.; Muravchik, C. H.

2011-12-01

The major goal of evoked related potential studies arise in source localization techniques to identify the loci of neural activity that give rise to a particular voltage distribution measured on the surface of the scalp. In this paper we evaluate the effect of the head model adopted in order to estimate the N170 component source in attention deficit hyperactivity disorder (ADHD) patients and control subjects, considering faces and words stimuli. The standardized low resolution brain electromagnetic tomography algorithm (sLORETA) is used to compare between the three shell spherical head model and a fully realistic model based on the ICBM-152 atlas. We compare their variance on source estimation and analyze the impact on the N170 source localization. Results show that the often used three shell spherical model may lead to erroneous solutions, specially on ADHD patients, so its use is not recommended. Our results also suggest that N170 sources are mainly located in the right occipital fusiform gyrus for faces stimuli and in the left occipital fusiform gyrus for words stimuli, for both control subjects and ADHD patients. We also found a notable decrease on the N170 estimated source amplitude on ADHD patients, resulting in a plausible marker of the disease.

Peripheral mechanisms for vocal production in birds - differences and similarities to human speech and singing.

PubMed

Riede, Tobias; Goller, Franz

2010-10-01

Song production in songbirds is a model system for studying learned vocal behavior. As in humans, bird phonation involves three main motor systems (respiration, vocal organ and vocal tract). The avian respiratory mechanism uses pressure regulation in air sacs to ventilate a rigid lung. In songbirds sound is generated with two independently controlled sound sources, which reside in a uniquely avian vocal organ, the syrinx. However, the physical sound generation mechanism in the syrinx shows strong analogies to that in the human larynx, such that both can be characterized as myoelastic-aerodynamic sound sources. Similarities include active adduction and abduction, oscillating tissue masses which modulate flow rate through the organ and a layered structure of the oscillating tissue masses giving rise to complex viscoelastic properties. Differences in the functional morphology of the sound producing system between birds and humans require specific motor control patterns. The songbird vocal apparatus is adapted for high speed, suggesting that temporal patterns and fast modulation of sound features are important in acoustic communication. Rapid respiratory patterns determine the coarse temporal structure of song and maintain gas exchange even during very long songs. The respiratory system also contributes to the fine control of airflow. Muscular control of the vocal organ regulates airflow and acoustic features. The upper vocal tract of birds filters the sounds generated in the syrinx, and filter properties are actively adjusted. Nonlinear source-filter interactions may also play a role. The unique morphology and biomechanical system for sound production in birds presents an interesting model for exploring parallels in control mechanisms that give rise to highly convergent physical patterns of sound generation. More comparative work should provide a rich source for our understanding of the evolution of complex sound producing systems. Copyright © 2009 Elsevier Inc. All rights reserved.

The dorsal medial frontal cortex mediates automatic motor inhibition in uncertain contexts: evidence from combined fMRI and EEG studies.

PubMed

Albares, Marion; Lio, Guillaume; Criaud, Marion; Anton, Jean-Luc; Desmurget, Michel; Boulinguez, Philippe

2014-11-01

Response inhibition is commonly thought to rely on voluntary, reactive, selective, and relatively slow prefrontal mechanisms. In contrast, we suggest here that response inhibition is achieved automatically, nonselectively, within very short delays in uncertain environments. We modified a classical go/nogo protocol to probe context-dependent inhibitory mechanisms. Because no single neuroimaging method can definitely disentangle neural excitation and inhibition, we combined fMRI and EEG recordings in healthy humans. Any stimulus (go or nogo) presented in an uncertain context requiring action restraint was found to evoke activity changes in the supplementary motor complex (SMC) with respect to a control condition in which no response inhibition was required. These changes included: (1) An increase in event-related BOLD activity, (2) an attenuation of the early (170 ms) event related potential generated by a single, consistent source isolated by advanced blind source separation, and (3) an increase in the evoked-EEG Alpha power of this source. Considered together, these results suggest that the BOLD signal evoked by any stimulus in the SMC when the situation is unpredictable can be driven by automatic, nonselective, context-dependent inhibitory activities. This finding reveals the paradoxical mechanisms by which voluntary control of action may be achieved. The ability to provide controlled responses in unpredictable environments would require setting-up the automatic self-inhibitory circuitry within the SMC. Conversely, enabling automatic behavior when the environment becomes predictable would require top-down control to deactivate anticipatorily and temporarily the inhibitory set. Copyright © 2014 Wiley Periodicals, Inc.

Revealing unobserved factors underlying cortical activity with a rectified latent variable model applied to neural population recordings.

PubMed

Whiteway, Matthew R; Butts, Daniel A

2017-03-01

The activity of sensory cortical neurons is not only driven by external stimuli but also shaped by other sources of input to the cortex. Unlike external stimuli, these other sources of input are challenging to experimentally control, or even observe, and as a result contribute to variability of neural responses to sensory stimuli. However, such sources of input are likely not "noise" and may play an integral role in sensory cortex function. Here we introduce the rectified latent variable model (RLVM) in order to identify these sources of input using simultaneously recorded cortical neuron populations. The RLVM is novel in that it employs nonnegative (rectified) latent variables and is much less restrictive in the mathematical constraints on solutions because of the use of an autoencoder neural network to initialize model parameters. We show that the RLVM outperforms principal component analysis, factor analysis, and independent component analysis, using simulated data across a range of conditions. We then apply this model to two-photon imaging of hundreds of simultaneously recorded neurons in mouse primary somatosensory cortex during a tactile discrimination task. Across many experiments, the RLVM identifies latent variables related to both the tactile stimulation as well as nonstimulus aspects of the behavioral task, with a majority of activity explained by the latter. These results suggest that properly identifying such latent variables is necessary for a full understanding of sensory cortical function and demonstrate novel methods for leveraging large population recordings to this end. NEW & NOTEWORTHY The rapid development of neural recording technologies presents new opportunities for understanding patterns of activity across neural populations. Here we show how a latent variable model with appropriate nonlinear form can be used to identify sources of input to a neural population and infer their time courses. Furthermore, we demonstrate how these sources are related to behavioral contexts outside of direct experimental control. Copyright © 2017 the American Physiological Society.

Laterality of brain activity during motor imagery is modulated by the provision of source level neurofeedback.

PubMed

Boe, Shaun; Gionfriddo, Alicia; Kraeutner, Sarah; Tremblay, Antoine; Little, Graham; Bardouille, Timothy

2014-11-01

Motor imagery (MI) may be effective as an adjunct to physical practice for motor skill acquisition. For example, MI is emerging as an effective treatment in stroke neurorehabilitation. As in physical practice, the repetitive activation of neural pathways during MI can drive short- and long-term brain changes that underlie functional recovery. However, the lack of feedback about MI performance may be a factor limiting its effectiveness. The provision of feedback about MI-related brain activity may overcome this limitation by providing the opportunity for individuals to monitor their own performance of this endogenous process. We completed a controlled study to isolate neurofeedback as the factor driving changes in MI-related brain activity across repeated sessions. Eighteen healthy participants took part in 3 sessions comprised of both actual and imagined performance of a button press task. During MI, participants in the neurofeedback group received source level feedback based on activity from the left and right sensorimotor cortex obtained using magnetoencephalography. Participants in the control group received no neurofeedback. MI-related brain activity increased in the sensorimotor cortex contralateral to the imagined movement across sessions in the neurofeedback group, but not in controls. Task performance improved across sessions but did not differ between groups. Our results indicate that the provision of neurofeedback during MI allows healthy individuals to modulate regional brain activity. This finding has the potential to improve the effectiveness of MI as a tool in neurorehabilitation. Copyright © 2014 Elsevier Inc. All rights reserved.

Phytochemical screening and in vitro bioactivities of the extracts of aerial part of Boerhavia diffusa Linn.

PubMed Central

Apu, Apurba Sarker; Liza, Mahmuda Sultana; Jamaluddin, A.T.M.; Howlader, Md. Amran; Saha, Repon Kumer; Rizwan, Farhana; Nasrin, Nishat

2012-01-01

Objective To investigate the bioactivities of crude n-hexane, ethyl acetate and methanol extracts of aerial part of Boerhavia diffusa Linn. (B. diffusa) and its phytochemical analysis. Methods The identification of phytoconstituents and assay of antioxidant, thrombolytic, cytotoxic, antimicrobial activities were conducted using specific standard in vitro procedures. Results The results showed that the plant extracts were a rich source of phytoconstituents. Methanol extract showed higher antioxidant, thrombolytic activity and less cytotoxic activity than those of n-hexane and ethyl acetate extracts of B. diffusa. Among the bioactivities, antioxidant activity was the most notable compared to the positive control and thus could be a potential rich source of natural antioxidant. In case of antimicrobial screening, crude extracts of the plant showed remarkable antibacterial activity against tested microorganisms. All the extracts showed significant inhibitory activity against Candida albicuns, at a concentration of 1000 µg/disc. Conclusions The present findings suggest that, the plant widely available in Bangladesh, could be a prominent source of medicinally important natural compounds. PMID:23569993

Crew activity and motion effects on the space station

NASA Technical Reports Server (NTRS)

Rochon, Brian V.; Scheer, Steven A.

1987-01-01

Among the significant sources of internal disturbances that must be considered in the design of space station vibration control systems are the loads induced on the structure from various crew activities. Flight experiment T013, flown on the second manned mission of Skylab, measured force and moment time histories for a range of preplanned crew motions and activities. This experiment has proved itself invaluable as a source of on-orbit crew induced loads that has allowed a space station forcing function data base to be built. This will enable forced response such as acceleration and deflections, attributable to crew activity, to be calculated. The flight experiment, resultant database and structural model pre-processor, analysis examples and areas of combined research shall be described.

Source sparsity control of sound field reproduction using the elastic-net and the lasso minimizers.

PubMed

Gauthier, P-A; Lecomte, P; Berry, A

2017-04-01

Sound field reproduction is aimed at the reconstruction of a sound pressure field in an extended area using dense loudspeaker arrays. In some circumstances, sound field reproduction is targeted at the reproduction of a sound field captured using microphone arrays. Although methods and algorithms already exist to convert microphone array recordings to loudspeaker array signals, one remaining research question is how to control the spatial sparsity in the resulting loudspeaker array signals and what would be the resulting practical advantages. Sparsity is an interesting feature for spatial audio since it can drastically reduce the number of concurrently active reproduction sources and, therefore, increase the spatial contrast of the solution at the expense of a difference between the target and reproduced sound fields. In this paper, the application of the elastic-net cost function to sound field reproduction is compared to the lasso cost function. It is shown that the elastic-net can induce solution sparsity and overcomes limitations of the lasso: The elastic-net solves the non-uniqueness of the lasso solution, induces source clustering in the sparse solution, and provides a smoother solution within the activated source clusters.

Air Pollution and Control Legislation in India

NASA Astrophysics Data System (ADS)

P Bhave, Prashant; Kulkarni, Nikhil

2015-09-01

Air pollution in urban areas arises from multiple sources, which may vary with location and developmental activities. Anthropogenic activities as rampant industrialization, exploitation and over consumption of natural resources, ever growing population size are major contributors of air pollution. The presented review is an effort to discuss various aspects of air pollution and control legislation in India emphasizing on the history, present scenario, international treaties, gaps and drawbacks. The review also presents legislative controls with judicial response to certain landmark judgments related to air pollution. The down sides related to enforcement mechanism for the effective implementation of environmental laws for air pollution control have been highlighted.

Modeling study of natural emissions, source apportionment, and emission control of atmospheric mercury

NASA Astrophysics Data System (ADS)

Shetty, Suraj K.

Mercury (Hg) is a toxic pollutant and is important to understand its cycling in the environment. In this dissertation, a number of modeling investigations were conducted to better understand the emission from natural surfaces, the source-receptor relationship of the emissions, and emission reduction of atmospheric mercury. The first part of this work estimates mercury emissions from vegetation, soil and water surfaces using a number of natural emission processors and detailed (LAI) Leaf Area Index data from GIS (Geographic Information System) satellite products. East Asian domain was chosen as it contributes nearly 50% of the global anthropogenic mercury emissions into the atmosphere. The estimated annual natural mercury emissions (gaseous elemental mercury) in the domain are 834 Mg yr-1 with 462 Mg yr-1 contributing from China. Compared to anthropogenic sources, natural sources show greater seasonal variability (highest in simmer). The emissions are significant, sometimes dominant, contributors to total mercury emission in the regions. The estimates provide possible explanation for the gaps between the anthropogenic emission estimates based on activity data and the emission inferred from field observations in the regions. To understand the contribution of domestic emissions to mercury deposition in the United States, the second part of the work applies the mercury model of Community Multi-scale Air Quality Modeling system (CMAQ-Hg v4.6) to apportion the various emission sources attributing to the mercury wet and dry deposition in the 6 United States receptor regions. Contributions to mercury deposition from electric generating units (EGU), iron and steel industry (IRST), industrial point sources excluding EGU and IRST (OIPM), the remaining anthropogenic sources (RA), natural processes (NAT), and out-of-boundary transport (BC) in domain was estimated. The model results for 2005 compared reasonably well to field observations made by MDN (Mercury Deposition Network) and CAMNet (Canadian Atmospheric Mercury Measurement Network). The model estimated a total deposition of 474 Mg yr-1 to the CONUS (Contiguous United States) domain, with two-thirds being dry deposited. Reactive gaseous mercury contributed the most to 60% of deposition. Emission speciation distribution is a key factor for local deposition as contribution from large point sources can be as high as 75% near (< 100 km) the emission sources, indicating that emission reduction may result in direct deposition decrease near the source locations. Among the sources, BC contributes to about 68% to 91% of total deposition. Excluding the BC's contribution, EGU contributes to nearly 50% of deposition caused by CONUS emissions in the Northeast, Southeast and East Central regions, while emissions from natural processes are more important in the Pacific and West Central regions (contributing up to 40% of deposition). The modeling results implies that implementation of the new emission standards proposed by USEPA (United States Environmental Protection Agency) would significantly benefit regions that have larger contributions from EGU sources. Control of mercury emissions from coal combustion processes has attracted great attention due to its toxicity and the emission-control regulations and has lead to advancement in state-of-the-art control technologies that alleviate the impact of mercury on ecosystem and human health. This part of the work applies a sorption model to simulate adsorption of mercury in flue gases, onto a confined-bed of activated carbon. The model's performances were studied at various flue gas flow rates, inlet mercury concentrations and adsorption bed temperatures. The process simulated a flue gas, with inlet mercury concentration of 300 ppb, entering at a velocity of 0.3 m s-1 from the bottom into a fixed bed (inside bed diameter of 1 m and 3 m bed height; bed temperature of 25 °C) of activated carbon (particle size of 0.004 m with density of 0.5 g cm-3 and surface area of 90.25 cm2 g -1). The model result demonstrated that a batch of activated carbon bed was capable of controlling mercury emission for approximately 275 days after which further mercury uptake starts to decrease till it reaches about 500 days when additional control ceases. An increase in bed temperature significantly reduces mercury sorption capacity of the activated carbon. Increase in flue gas flow rate may result in faster consumption of sorption capacity initially but at a later stage, the sorption rate decreases due to reduced sorption capacity. Thus, overall sorption rate remains unaffected. The activated carbon's effective life (time to reach saturation) is not affected by inlet mercury concentration, implying that the designing and operation of a mercury sorption process can be done independently. The results provide quantitative indication for designing efficient confined-bed process to remove mercury from flue gases.

Effects of morphological control on the characteristics of vertical-type OTFTs using Alq3.

PubMed

Kim, Young Do; Park, Jong Wook; Kang, In Nam; Oh, Se Young

2008-09-01

We have fabricated vertical-type organic thin-film transistors (OTFTs) using tris-(8-hydroxyquinoline) aluminum (Alq(3)) as an n-type active material. Vertical-type OTFT using Alq(3) has a layered structure of Al(source electrode)/Alq(3)(active layer)/Al(gate electrode)/Alq(3)(active layer)/ITO glass(drain electrode). Alq(3) thin films containing various surface morphologies could be obtained by the control of evaporation rate and substrate temperature. The effects of the morphological control of Alq(3) thin layer on the grain size and the flatness of film surface were investigated. The characteristics of vertical-type OTFT significantly influenced the growth condition of Alq(3) layer.

A double-panel active segmented partition module using decoupled analog feedback controllers: numerical model.

PubMed

Sagers, Jason D; Leishman, Timothy W; Blotter, Jonathan D

2009-06-01

Low-frequency sound transmission has long plagued the sound isolation performance of lightweight partitions. Over the past 2 decades, researchers have investigated actively controlled structures to prevent sound transmission from a source space into a receiving space. An approach using active segmented partitions (ASPs) seeks to improve low-frequency sound isolation capabilities. An ASP is a partition which has been mechanically and acoustically segmented into a number of small individually controlled modules. This paper provides a theoretical and numerical development of a single ASP module configuration, wherein each panel of the double-panel structure is independently actuated and controlled by an analog feedback controller. A numerical model is developed to estimate frequency response functions for the purpose of controller design, to understand the effects of acoustic coupling between the panels, to predict the transmission loss of the module in both passive and active states, and to demonstrate that the proposed ASP module will produce bidirectional sound isolation.

Controlled-source seismic interferometry with one way wave fields

NASA Astrophysics Data System (ADS)

van der Neut, J.; Wapenaar, K.; Thorbecke, J. W.

2008-12-01

In Seismic Interferometry we generally cross-correlate registrations at two receiver locations and sum over an array of sources to retrieve a Green's function as if one of the receiver locations hosts a (virtual) source and the other receiver location hosts an actual receiver. One application of this concept is to redatum an area of surface sources to a downhole receiver location, without requiring information about the medium between the sources and receivers, thus providing an effective tool for imaging below complex overburden, which is also known as the Virtual Source method. We demonstrate how elastic wavefield decomposition can be effectively combined with controlled-source Seismic Interferometry to generate virtual sources in a downhole receiver array that radiate only down- or upgoing P- or S-waves with receivers sensing only down- or upgoing P- or S- waves. For this purpose we derive exact Green's matrix representations from a reciprocity theorem for decomposed wavefields. Required is the deployment of multi-component sources at the surface and multi- component receivers in a horizontal borehole. The theory is supported with a synthetic elastic model, where redatumed traces are compared with those of a directly modeled reflection response, generated by placing active sources at the virtual source locations and applying elastic wavefield decomposition on both source and receiver side.

Functional source separation and hand cortical representation for a brain–computer interface feature extraction

PubMed Central

Tecchio, Franca; Porcaro, Camillo; Barbati, Giulia; Zappasodi, Filippo

2007-01-01

A brain–computer interface (BCI) can be defined as any system that can track the person's intent which is embedded in his/her brain activity and, from it alone, translate the intention into commands of a computer. Among the brain signal monitoring systems best suited for this challenging task, electroencephalography (EEG) and magnetoencephalography (MEG) are the most realistic, since both are non-invasive, EEG is portable and MEG could provide more specific information that could be later exploited also through EEG signals. The first two BCI steps require set up of the appropriate experimental protocol while recording the brain signal and then to extract interesting features from the recorded cerebral activity. To provide information useful in these BCI stages, our aim is to provide an overview of a new procedure we recently developed, named functional source separation (FSS). As it comes from the blind source separation algorithms, it exploits the most valuable information provided by the electrophysiological techniques, i.e. the waveform signal properties, remaining blind to the biophysical nature of the signal sources. FSS returns the single trial source activity, estimates the time course of a neuronal pool along different experimental states on the basis of a specific functional requirement in a specific time period, and uses the simulated annealing as the optimization procedure allowing the exploit of functional constraints non-differentiable. Moreover, a minor section is included, devoted to information acquired by MEG in stroke patients, to guide BCI applications aiming at sustaining motor behaviour in these patients. Relevant BCI features – spatial and time-frequency properties – are in fact altered by a stroke in the regions devoted to hand control. Moreover, a method to investigate the relationship between sensory and motor hand cortical network activities is described, providing information useful to develop BCI feedback control systems. This review provides a description of the FSS technique, a promising tool for the BCI community for online electrophysiological feature extraction, and offers interesting information to develop BCI applications to sustain hand control in stroke patients. PMID:17331989

Optical interferometer testbed

NASA Technical Reports Server (NTRS)

Blackwood, Gary H.

1991-01-01

Viewgraphs on optical interferometer testbed presented at the MIT Space Research Engineering Center 3rd Annual Symposium are included. Topics covered include: space-based optical interferometer; optical metrology; sensors and actuators; real time control hardware; controlled structures technology (CST) design methodology; identification for MIMO control; FEM/ID correlation for the naked truss; disturbance modeling; disturbance source implementation; structure design: passive damping; low authority control; active isolation of lightweight mirrors on flexible structures; open loop transfer function of mirror; and global/high authority control.

The neurocognitive basis of borrowed context information.

PubMed

O'Neill, Meagan; Diana, Rachel A

2017-06-01

Falsely remembered items can be accompanied by episodic context retrieval. This finding is difficult to explain because there is no episode that binds the remembered item to the experimenter-controlled context features. The current study examines the neural correlates of false context retrieval when the context features can be traced to encoding episodes of semantically-similar items. Our neuroimaging results support a "dissociated source" mechanism for context borrowing in false memory. We found that parahippocampal cortex (PHc) activation, thought to indicate context retrieval, was greater during trials that involved context borrowing (an incorrect, but plausible source decision) than during baseline correct context retrieval. In contrast, hippocampal activation, thought to indicate retrieval of an episodic binding, was stronger during correct source retrieval than during context borrowing. Vivid context retrieval during false recollection experiences was also indicated by increased activation in visual perceptual regions for context borrowing as compared to other incorrect source judgments. The pattern of findings suggests that context borrowing can arise when unusually strong activation of a semantically-related item's contextual features drives relatively weak retrieval of the associated episodic binding with failure to confirm the item information within that binding. This dissociated source retrieval mechanism suggests that context-driven episodic retrieval does not necessarily lead to retrieval of specific item details. That is, source information can be retrieved in the absence of item memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

Causal feedforward control of a stochastically excited fuselage structure with active sidewall panel.

PubMed

Misol, Malte; Haase, Thomas; Monner, Hans Peter; Sinapius, Michael

2014-10-01

This paper provides experimental results of an aircraft-relevant double panel structure mounted in a sound transmission loss facility. The primary structure of the double panel system is excited either by a stochastic point force or by a diffuse sound field synthesized in the reverberation room of the transmission loss facility. The secondary structure, which is connected to the frames of the primary structure, is augmented by actuators and sensors implementing an active feedforward control system. Special emphasis is placed on the causality of the active feedforward control system and its implications on the disturbance rejection at the error sensors. The coherence of the sensor signals is analyzed for the two different disturbance excitations. Experimental results are presented regarding the causality, coherence, and disturbance rejection of the active feedforward control system. Furthermore, the sound transmission loss of the double panel system is evaluated for different configurations of the active system. A principal result of this work is the evidence that it is possible to strongly influence the transmission of stochastic disturbance sources through double panel configurations by means of an active feedforward control system.

Lead Exposures in U.S. Children, 2008: Implications for Prevention

PubMed Central

Levin, Ronnie; Brown, Mary Jean; Kashtock, Michael E.; Jacobs, David E.; Whelan, Elizabeth A.; Rodman, Joanne; Schock, Michael R.; Padilla, Alma; Sinks, Thomas

2008-01-01

Objective We reviewed the sources of lead in the environments of U.S. children, contributions to children’s blood lead levels, source elimination and control efforts, and existing federal authorities. Our context is the U.S. public health goal to eliminate pediatric elevated blood lead levels (EBLs) by 2010. Data sources National, state, and local exposure assessments over the past half century have identified risk factors for EBLs among U.S. children, including age, race, income, age and location of housing, parental occupation, and season. Data extraction and synthesis Recent national policies have greatly reduced lead exposure among U.S. children, but even very low exposure levels compromise children’s later intellectual development and lifetime achievement. No threshold for these effects has been demonstrated. Although lead paint and dust may still account for up to 70% of EBLs in U.S. children, the U.S. Centers for Disease Control and Prevention estimates that ≥30% of current EBLs do not have an immediate lead paint source, and numerous studies indicate that lead exposures result from multiple sources. EBLs and even deaths have been associated with inadequately controlled sources including ethnic remedies and goods, consumer products, and food-related items such as ceramics. Lead in public drinking water and in older urban centers remain exposure sources in many areas. Conclusions Achieving the 2010 goal requires maintaining current efforts, especially programs addressing lead paint, while developing interventions that prevent exposure before children are poisoned. It also requires active collaboration across all levels of government to identify and control all potential sources of lead exposure, as well as primary prevention. PMID:18941567

DEMONSTRATION OF A PAINT SPRAY BOOTH EMISSION CONTROL STRATEGY USING RECIRCULATION/PARTITIONING & UV/OZONE POLLUTION EMISSION CONTROL - VOLUME 1. TECHNICAL REPORT

EPA Science Inventory

The report describes in detail the source testing, construction, and data reduction/analysis activities that comprise the three phases of a technology demonstration program. Phase I consisted of a detailed baseline evaluation of several paint spray booths operated at the Barstow,...

Active noise control using noise source having adaptive resonant frequency tuning through stiffness variation

NASA Technical Reports Server (NTRS)

Rajiyah, Harindra (Inventor); Hedeen, Robert A. (Inventor); Pla, Frederic G. (Inventor); Renshaw, Anthony A. (Inventor)

1995-01-01

A noise source for an aircraft engine active noise cancellation system in which the resonant frequency of a noise radiating element is tuned to permit noise cancellation over a wide range of frequencies. The resonant frequency of the noise radiating element is tuned by a plurality of force transmitting mechanisms which contact the noise radiating element. Each one of the force transmitting mechanisms includes an expandable element and a spring in contact with the noise radiating element so that excitation of the element varies the spring force applied to the noise radiating element. The elements are actuated by a controller which receives input of a signal proportional to displacement of the noise radiating element and a signal corresponding to the blade passage frequency of the engine's fan. In response, the controller determines a control signal which is sent to the elements and causes the spring force applied to the noise radiating element to be varied. The force transmitting mechanisms can be arranged to either produce bending or linear stiffness variations in the noise radiating element.

Wave field synthesis, adaptive wave field synthesis and ambisonics using decentralized transformed control: Potential applications to sound field reproduction and active noise control

NASA Astrophysics Data System (ADS)

Gauthier, Philippe-Aubert; Berry, Alain; Woszczyk, Wieslaw

2005-09-01

Sound field reproduction finds applications in listening to prerecorded music or in synthesizing virtual acoustics. The objective is to recreate a sound field in a listening environment. Wave field synthesis (WFS) is a known open-loop technology which assumes that the reproduction environment is anechoic. Classical WFS, therefore, does not perform well in a real reproduction space such as room. Previous work has suggested that it is physically possible to reproduce a progressive wave field in-room situation using active control approaches. In this paper, a formulation of adaptive wave field synthesis (AWFS) introduces practical possibilities for an adaptive sound field reproduction combining WFS and active control (with WFS departure penalization) with a limited number of error sensors. AWFS includes WFS and closed-loop ``Ambisonics'' as limiting cases. This leads to the modification of the multichannel filtered-reference least-mean-square (FXLMS) and the filtered-error LMS (FELMS) adaptive algorithms for AWFS. Decentralization of AWFS for sound field reproduction is introduced on the basis of sources' and sensors' radiation modes. Such decoupling may lead to decentralized control of source strength distributions and may reduce computational burden of the FXLMS and the FELMS algorithms used for AWFS. [Work funded by NSERC, NATEQ, Université de Sherbrooke and VRQ.] Ultrasound/Bioresponse to

Lunar seismicity and tectonics

NASA Technical Reports Server (NTRS)

Lammlein, D. R.

1977-01-01

Results are presented for an analysis of all moonquake data obtained by the Apollo seismic stations during the period from November 1969 to May 1974 and a preliminary analysis of critical data obtained in the interval from May 1974 to May 1975. More accurate locations are found for previously located moonquakes, and additional sources are located. Consideration is given to the sources of natural seismic signals, lunar seismic activity, moonquake periodicities, tidal periodicities in moonquake activity, hypocentral locations and occurrence characteristics of deep and shallow moonquakes, lunar tidal control over moonquakes, lunar tectonism, the locations of moonquake belts, and the dynamics of the lunar interior. It is concluded that: (1) moonquakes are distributed in several major belts of global extent that coincide with regions of the youngest and most intense volcanic and tectonic activity; (2) lunar tides control both the small quakes occurring at great depth and the larger quakes occurring near the surface; (3) the moon has a much thicker lithosphere than earth; (4) a single tectonic mechanism may account for all lunar seismic activity; and (5) lunar tidal stresses are an efficient triggering mechanism for moonquakes.

Provider communication with adolescent and young females during sexual and reproductive health visits: findings from the 2011-2015 National Survey of Family Growth.

PubMed

Liddon, Nicole; Steiner, Riley J; Martinez, Gladys M

2018-01-01

This study assesses provider communication with adolescent and young women about birth control, emergency contraception and condoms during sexual and reproductive health visits. Using data from sexually active 15-24-year-old women in the 2011-2015 National Survey of Family Growth, we examined provider communication about contraception and condoms at sexual and reproductive health services in the past year and assessed differences by demographics, sexual behavior and source of care. Approximately two thirds of women received provider communication about condoms (65.0%) and birth control (64.0%-66.8%). Communication was higher among Title-X-funded clinic vs. private providers. Differences by age, race/ethnicity, mother's education, number of partners and condom use were also found. Most sexually active young women attending sexual and reproductive health visits received provider communication about condoms and birth control, but communication is not universal and varies by source of care, demographics and sexual behavior. Copyright © 2017. Published by Elsevier Inc.

Evaluation of the sources of contamination in the suburban area of Koropi-Markopoulo, Athens, Greece.

PubMed

Kaitantzian, Agavni; Kelepertzis, Efstratios; Kelepertsis, Akindynos

2013-07-01

Heavy metal concentrations were monitored in agricultural soils and irrigation groundwaters of Koropi-Markopoulo area, a representative agricultural suburb in Athens, Greece, aiming at the identification of the sources of contaminants. Multivariate analyses of geochemical data demonstrated that agricultural practices and industrial activities considerably affected the quality of both environmental compartments. The levels of Ni, Cr, Co, Mn and Fe in agricultural soils were associated with geological parent materials whereas Pb, Zn and Cu mainly originated from anthropic activities. Referring to groundwaters, individual major anions and cations (K⁺, Na⁺, Ca²⁺, Mg²⁺, NO₃⁻, SO₄²⁻, Cl⁻) were influenced by various natural and anthropogenic factors whereas Ni, Cr, Cu and Zn were controlled by industrial and agronomic activities. The identification of the sources of contaminants in soil and groundwater environments is a valuable basis for encouraging mitigation strategies preventing further quality degradation.

Infinite non-causality in active cancellation of random noise

NASA Astrophysics Data System (ADS)

Friot, Emmanuel

2006-03-01

Active cancellation of broadband random noise requires the detection of the incoming noise with some time advance. In an duct for example this advance must be larger than the delays in the secondary path from the control source to the error sensor. In this paper it is shown that, in some cases, the advance required for perfect noise cancellation is theoretically infinite because the inverse of the secondary path, which is required for control, can include an infinite non-causal response. This is shown to be the result of two mechanisms: in the single-channel case (one control source and one error sensor), this can arise because of strong echoes in the control path. In the multi-channel case this can arise even in free field simply because of an unfortunate placing of sensors and actuators. In the present paper optimal feedforward control is derived through analytical and numerical computations, in the time and frequency domains. It is shown that, in practice, the advance required for significant noise attenuation can be much larger than the secondary path delays. Practical rules are also suggested in order to prevent infinite non-causality from appearing.

Combining controlled-source seismology and receiver function information to derive 3-D Moho topography for Italy

NASA Astrophysics Data System (ADS)

Spada, M.; Bianchi, I.; Kissling, E.; Agostinetti, N. Piana; Wiemer, S.

2013-08-01

The accurate definition of 3-D crustal structures and, in primis, the Moho depth, are the most important requirement for seismological, geophysical and geodynamic modelling in complex tectonic regions. In such areas, like the Mediterranean region, various active and passive seismic experiments are performed, locally reveal information on Moho depth, average and gradient crustal Vp velocity and average Vp/Vs velocity ratios. Until now, the most reliable information on crustal structures stems from controlled-source seismology experiments. In most parts of the Alpine region, a relatively large number of controlled-source seismology information are available though the overall coverage in the central Mediterranean area is still sparse due to high costs of such experiments. Thus, results from other seismic methodologies, such as local earthquake tomography, receiver functions and ambient noise tomography can be used to complement the controlled-source seismology information to increase coverage and thus the quality of 3-D crustal models. In this paper, we introduce a methodology to directly combine controlled-source seismology and receiver functions information relying on the strengths of each method and in relation to quantitative uncertainty estimates for all data to derive a well resolved Moho map for Italy. To obtain a homogeneous elaboration of controlled-source seismology and receiver functions results, we introduce a new classification/weighting scheme based on uncertainty assessment for receiver functions data. In order to tune the receiver functions information quality, we compare local receiver functions Moho depths and uncertainties with a recently derived well-resolved local earthquake tomography-derived Moho map and with controlled-source seismology information. We find an excellent correlation in the Moho information obtained by these three methodologies in Italy. In the final step, we interpolate the controlled-source seismology and receiver functions information to derive the map of Moho topography in Italy and surrounding regions. Our results show high-frequency undulation in the Moho topography of three different Moho interfaces, the European, the Adriatic-Ionian, and the Liguria-Corsica-Sardinia-Tyrrhenia, reflecting the complexity of geodynamical evolution.

Entertainment and Pacification System For Car Seat

NASA Technical Reports Server (NTRS)

Elrod, Susan Vinz (Inventor); Dabney, Richard W. (Inventor)

2006-01-01

An entertainment and pacification system for use with a child car seat has speakers mounted in the child car seat with a plurality of audio sources and an anti-noise audio system coupled to the child car seat. A controllable switching system provides for, at any given time, the selective activation of i) one of the audio sources such that the audio signal generated thereby is coupled to one or more of the speakers, and ii) the anti-noise audio system such that an ambient-noise-canceling audio signal generated thereby is coupled to one or more of the speakers. The controllable switching system can receive commands generated at one of first controls located at the child car seat and second controls located remotely with respect to the child car seat with commands generated by the second controls overriding commands generated by the first controls.

Water Tunnel Studies of Dynamic Wing Flap Effects

DTIC Science & Technology

2016-06-01

applications where dynamic flaps have been studied are in the active elevon rotor and wind turbines . Any analytical or computational study needs to be...observed here that most of these pertain to other applications such as rotorcraft and wind turbine flow control. At times, a Gurney flap has been for...the flap-slices used. Source: [12]. .......................14 Figure 6. NACA 2212 at wind tunnel section. Source: [8

The Cortical Organization of Speech Processing: Feedback Control and Predictive Coding the Context of a Dual-Stream Model

ERIC Educational Resources Information Center

Hickok, Gregory

2012-01-01

Speech recognition is an active process that involves some form of predictive coding. This statement is relatively uncontroversial. What is less clear is the source of the prediction. The dual-stream model of speech processing suggests that there are two possible sources of predictive coding in speech perception: the motor speech system and the…

Evaluation of Chemical Coating Processes for AXAF

NASA Technical Reports Server (NTRS)

Engelhaupt, Darell E.

1997-01-01

The need existed at MSFC for the development and fabrication of radioisotope calibration sources of cadmium 109 and iron 55 isotopes. This was in urgent response to the AXAF program. Several issues persisted in creating manufacturing difficulties for the supplier. In order to meet the MSFC requirements very stringent control needed to be maintained for the coating quality, specific activity and thickness. Due to the difficulties in providing the precisely controlled devices for testing, the delivery of the sources was seriously delayed. It became imperative that these fabrication issues be resolved to avoid further delays in this AXAF observatory key component.

Aqueous and Organic Solvent-Extracts of Selected South African Medicinal Plants Possess Antimicrobial Activity against Drug-Resistant Strains of Helicobacter pylori: Inhibitory and Bactericidal Potential

PubMed Central

Njume, Collise; Jide, Afolayan A.; Ndip, Roland N.

2011-01-01

The aim of this study was to identify sources of cheap starting materials for the synthesis of new drugs against Helicobacter pylori. Solvent-extracts of selected medicinal plants; Combretum molle, Sclerocarya birrea, Garcinia kola, Alepidea amatymbica and a single Strychnos species were investigated against 30 clinical strains of H. pylori alongside a reference control strain (NCTC 11638) using standard microbiological techniques. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. All the plants demonstrated anti-H. pylori activity with zone diameters of inhibition between 0 and 38 mm and 50% minimum inhibitory concentration (MIC50) values ranging from 0.06 to 5.0 mg/mL. MIC50 values for amoxicillin and metronidazole ranged from 0.001 to 0.63 mg/mL and 0.004 to 5.0 mg/mL respectively. The acetone extracts of C. molle and S. birrea exhibited a remarkable bactericidal activity against H. pylori killing more than 50% of the strains within 18 h at 4× MIC and complete elimination of the organisms within 24 h. Their antimicrobial activity was comparable to the control antibiotics. However, the activity of the ethanol extract of G. kola was lower than amoxicillin (P < 0.05) as opposed to metronidazole (P > 0.05). These results demonstrate that S. birrea, C. molle and G. kola may represent good sources of compounds with anti-H. pylori activity. PMID:22016616

Aqueous and organic solvent-extracts of selected south African medicinal plants possess antimicrobial activity against drug-resistant strains of Helicobacter pylori: inhibitory and bactericidal potential.

PubMed

Njume, Collise; Jide, Afolayan A; Ndip, Roland N

2011-01-01

The aim of this study was to identify sources of cheap starting materials for the synthesis of new drugs against Helicobacter pylori. Solvent-extracts of selected medicinal plants; Combretum molle, Sclerocarya birrea, Garcinia kola, Alepidea amatymbica and a single Strychnos species were investigated against 30 clinical strains of H. pylori alongside a reference control strain (NCTC 11638) using standard microbiological techniques. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. All the plants demonstrated anti-H. pylori activity with zone diameters of inhibition between 0 and 38 mm and 50% minimum inhibitory concentration (MIC(50)) values ranging from 0.06 to 5.0 mg/mL. MIC(50) values for amoxicillin and metronidazole ranged from 0.001 to 0.63 mg/mL and 0.004 to 5.0 mg/mL respectively. The acetone extracts of C. molle and S. birrea exhibited a remarkable bactericidal activity against H. pylori killing more than 50% of the strains within 18 h at 4× MIC and complete elimination of the organisms within 24 h. Their antimicrobial activity was comparable to the control antibiotics. However, the activity of the ethanol extract of G. kola was lower than amoxicillin (P < 0.05) as opposed to metronidazole (P > 0.05). These results demonstrate that S. birrea, C. molle and G. kola may represent good sources of compounds with anti-H. pylori activity.

Hemolytic and antimicrobial activities differ among saponin-rich extracts from guar, quillaja, yucca, and soybean.

PubMed

Hassan, Sherif M; Byrd, James A; Cartwright, Aubry L; Bailey, Chris A

2010-10-01

Hemolytic and antibacterial activities of eight serial concentrations ranged from 5-666 microg/mL of saponin-rich extracts from guar meal (GM), quillaja, yucca, and soybean were tested in 96-well plates and read by enzyme-linked immunosorbent assay plate-well as 650 nm. Hemolytic assay used a 1% suspension of chicken red blood cells with water and phosphate buffered saline as positive and negative controls, respectively. Antibacterial activity against Staphylococcus aureus, Salmonella typhimurium, and Escherichia coli were evaluated using ampicillin and bacteria without saponin-rich extract as positive and negative controls, respectively. The 100% MeOH GM and commercial quillaja saponin-rich extracts were significantly the highest in both hemolytic and antibacterial activities against all bacteria at the same concentration tested. Soybean saponin-rich extract had no antibacterial activity against any of the bacteria at the concentrations tested while yucca saponin-rich extract had no antibacterial activity against the gram-negative bacteria at the concentrations tested. GM and quillaja saponin-rich extracts were hemolytic, while yucca and soybean saponin-rich extracts were not hemolytic at the concentrations tested. No saponin-rich extract source had antibacterial activity against S. typhimurium or E. coli at the concentrations tested. Both GM and quillaja saponin-rich extracts exhibited antibacterial activity against S. aureus. Saponin-rich extracts from different plant sources have different hemolytic and antibacterial activities.

Regional Patterns of Elevated Alpha and High-Frequency Electroencephalographic Activity during Nonrapid Eye Movement Sleep in Chronic Insomnia: A Pilot Study

PubMed Central

Riedner, Brady A.; Goldstein, Michael R.; Plante, David T.; Rumble, Meredith E.; Ferrarelli, Fabio; Tononi, Giulio; Benca, Ruth M.

2016-01-01

Study Objectives: To examine nonrapid eye movement (NREM) sleep in insomnia using high-density electroencephalography (EEG). Methods: All-night sleep recordings with 256 channel high-density EEG were analyzed for 8 insomnia subjects (5 females) and 8 sex and age-matched controls without sleep complaints. Spectral analyses were conducted using unpaired t-tests and topographical differences between groups were assessed using statistical non-parametric mapping. Five minute segments of deep NREM sleep were further analyzed using sLORETA cortical source imaging. Results: The initial topographic analysis of all-night NREM sleep EEG revealed that insomnia subjects had more high-frequency EEG activity (> 16 Hz) compared to good sleeping controls and that the difference between groups was widespread across the scalp. In addition, the analysis also showed that there was a more circumscribed difference in theta (4–8 Hz) and alpha (8–12 Hz) power bands between groups. When deep NREM sleep (N3) was examined separately, the high-frequency difference between groups diminished, whereas the higher regional alpha activity in insomnia subjects persisted. Source imaging analysis demonstrated that sensory and sensorimotor cortical areas consistently exhibited elevated levels of alpha activity during deep NREM sleep in insomnia subjects relative to good sleeping controls. Conclusions: These results suggest that even during the deepest stage of sleep, sensory and sensorimotor areas in insomnia subjects may still be relatively active compared to control subjects and to the rest of the sleeping brain. Citation: Riedner BA, Goldstein MR, Plante DT, Rumble ME, Ferrarelli F, Tononi G, Benca RM. Regional patterns of elevated alpha and high-frequency electroencephalographic activity during nonrapid eye movement sleep in chronic insomnia: a pilot study. SLEEP 2016;39(4):801–812. PMID:26943465

Effects of dietary organic, inorganic, and nanoparticulate selenium sources on growth, hemato-immunological, and serum biochemical parameters of common carp (Cyprinus carpio).

PubMed

Saffari, Sadegh; Keyvanshokooh, Saeed; Zakeri, Mohammad; Johari, Seyed Ali; Pasha-Zanoosi, Hossein; Mozanzadeh, Mansour Torfi

2018-04-16

An 8-week feeding trial was conducted to compare the effects of supplementing (0.7 mg kg -1 ) different dietary selenium (Se) sources including organic [selenomethionine (SeMet)], inorganic [sodium selenite (Na 2 SeO 3 )], and nanoparticulate Se (nano-Se) on physiological responses of common carp, Cyprinus carpio juveniles (9.7 ± 0.1 g). Basal diet without Se supplementation used as control. Fish fed nano-Se supplemented diet had the highest weight gain (97.2 ± 10.8%) and feed efficiency ratio (42.4 ± 0.8%). Intestinal villi height was significantly taller in fish fed nano-Se diet than in the control group in both foregut and midgut sections. Serum glutathione peroxidase and superoxide dismutase activities were significantly higher in nano-Se and SeMet groups than in control and sodium selenite groups. Fish fed Se-supplemented diets had greater red blood cell counts and hematocrit and hemoglobin values than the control group (P < 0.05). Nano-Se and SeMet groups showed a significant increase in white blood cell counts, neutrophil percentage, and serum lysozyme activity than the other groups. Fish fed nano-Se diet had the highest serum hemolytic activity, total immunoglobulin, and total protein and albumin contents, as well as the lowest serum total cholesterol and low density lipoprotein levels (P < 0.05). Overall, significant improvements in growth performance, feed utilization, intestinal morphology, and hemato-immunological and serum biochemical parameters of common carp juveniles suggest nano-Se as an efficient source for providing dietary Se in this species.

Are the Traditional Medical Uses of Muricidae Molluscs Substantiated by Their Pharmacological Properties and Bioactive Compounds?

PubMed Central

Benkendorff, Kirsten; Rudd, David; Devi Nongmaithem, Bijayalakshmi; Liu, Lei; Young, Fiona; Edwards, Vicki; Avila, Cathy; Abbott, Catherine A.

2015-01-01

Marine molluscs from the family Muricidae hold great potential for development as a source of therapeutically useful compounds. Traditionally known for the production of the ancient dye Tyrian purple, these molluscs also form the basis of some rare traditional medicines that have been used for thousands of years. Whilst these traditional and alternative medicines have not been chemically analysed or tested for efficacy in controlled clinical trials, a significant amount of independent research has documented the biological activity of extracts and compounds from these snails. In particular, Muricidae produce a suite of brominated indoles with anti-inflammatory, anti-cancer and steroidogenic activity, as well as choline esters with muscle-relaxing and pain relieving properties. These compounds could explain some of the traditional uses in wound healing, stomach pain and menstrual problems. However, the principle source of bioactive compounds is from the hypobranchial gland, whilst the shell and operculum are the main source used in most traditional remedies. Thus further research is required to understand this discrepancy and to optimise a quality controlled natural medicine from Muricidae. PMID:26295242

Design and Analysis Tools for Concurrent Blackboard Systems

NASA Technical Reports Server (NTRS)

McManus, John W.

1991-01-01

A blackboard system consists of a set of knowledge sources, a blackboard data structure, and a control strategy used to activate the knowledge sources. The blackboard model of problem solving is best described by Dr. H. Penny Nii of the Stanford University AI Laboratory: "A Blackboard System can be viewed as a collection of intelligent agents who are gathered around a blackboard, looking at pieces of information written on it, thinking about the current state of the solution, and writing their conclusions on the blackboard as they generate them. " The blackboard is a centralized global data structure, often partitioned in a hierarchical manner, used to represent the problem domain. The blackboard is also used to allow inter-knowledge source communication and acts as a shared memory visible to all of the knowledge sources. A knowledge source is a highly specialized, highly independent process that takes inputs from the blackboard data structure, performs a computation, and places the results of the computation in the blackboard data structure. This design allows for an opportunistic control strategy. The opportunistic problem-solving technique allows a knowledge source to contribute towards the solution of the current problem without knowing which of the other knowledge sources will use the information. The use of opportunistic problem-solving allows the data transfers on the blackboard to determine which processes are active at a given time. Designing and developing blackboard systems is a difficult process. The designer is trying to balance several conflicting goals and achieve a high degree of concurrent knowledge source execution while maintaining both knowledge and semantic consistency on the blackboard. Blackboard systems have not attained their apparent potential because there are no established tools or methods to guide in their construction or analyze their performance.

The engagement of cortical areas preceding exogenous vergence eye movements.

PubMed

Wojtczak-Kwaśniewska, Monika; Przekoracka-Krawczyk, Anna; Van der Lubbe, Rob H J

2018-01-01

Source analyses on event related potentials (ERPs) derived from the electroencephalogram (EEG) were performed to examine the respective roles of cortical areas preceding exogenously triggered saccades, combined convergences, and combined divergences. All eye movements were triggered by the offset of a central fixation light emitting diode (LED) and the onset of a lateral LED at various depths in an otherwise fully darkened room. Our analyses revealed that three source pairs, two located in the frontal lobe-the frontal eye fields (FEF) and an anterior frontal area-, and one located within the occipital cortex, can account for 99.2% of the observed ERPs. Overall, the comparison between source activities revealed the largest activity in the occipital cortex, while no difference in activity between FEF and the anterior frontal area was obtained. For all sources, increased activity was observed for combined vergences, especially combined convergences, relative to saccades. Behavioral results revealed that onset latencies were longest for combined convergences, intermediate for combined divergences, and the shortest for saccades. Together, these findings fit within a perspective in which both occipital and frontal areas play an important role in retinal disparity detection. In the case of saccades and combined divergences stimulus-locked activity was larger than response-locked activity, while no difference between stimulus- and response-locked activity was observed for combined convergences. These findings seem to imply that the electrophysiological activity preceding exogenous eye movements consists of a sensory-related part that is under cortical control, while subcortical structures may be held responsible for final execution.

PM RESEARCH

EPA Science Inventory

Activity Area (F03): PM Implementation NRMRL conducts research to improve the techniques used to quantify PM and PM precursor emissions from stationary, mobile, and fugitive sources and investigates the performance and cost of innovative control technology systems. The emission...

Hazardous waste management in the Pacific basin

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

Cirillo, R.R.; Chiu, S.; Chun, K.C.

1994-11-01

Hazardous waste control activities in Asia and the Pacific have been reviewed. The review includes China (mainland, Hong Kong, and Taiwan), Indonesia, Korea, Malaysia, Papua New Guinea, the Philippines, Singapore, and Thailand. It covers the sources of hazardous waste, the government structure for dealing with hazardous waste, and current hazardous waste control activities in each country. In addition, the hazardous waste program activities of US government agencies, US private-sector organizations, and international organizations are reviewed. The objective of these reviews is to provide a comprehensive picture of the current hazardous waste problems and the waste management approaches being used tomore » address them so that new program activities can be designed more efficiently.« less

40 CFR 63.11221 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2012 CFR

2012-07-01

... malfunctions or out-of-control periods, or required monitoring system quality assurance or control activities... collect data according to this section. (b) You must operate the monitoring system and collect data at all required intervals at all times the affected source is operating except for periods of monitoring system...

40 CFR 63.11221 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2011 CFR

2011-07-01

... malfunctions or out-of-control periods, or required monitoring system quality assurance or control activities... collect data according to this section. (b) You must operate the monitoring system and collect data at all required intervals at all times the affected source is operating except for periods of monitoring system...

Sperm whales reduce foraging effort during exposure to 1-2 kHz sonar and killer whale sounds.

PubMed

Isojunno, Saana; Cure, Charlotte; Kvadsheim, Petter Helgevold; Lam, Frans-Peter Alexander; Tyack, Peter Lloyd; Wensveen, Paul Jacobus; Miller, Patrick James O'Malley

2016-01-01

The time and energetic costs of behavioral responses to incidental and experimental sonar exposures, as well as control stimuli, were quantified using hidden state analysis of time series of acoustic and movement data recorded by tags (DTAG) attached to 12 sperm whales (Physeter macrocephalus) using suction cups. Behavioral state transition modeling showed that tagged whales switched to a non-foraging, non-resting state during both experimental transmissions of low-frequency active sonar from an approaching vessel (LFAS; 1-2 kHz, source level 214 dB re 1 µPa m, four tag records) and playbacks of potential predator (killer whale, Orcinus orca) sounds broadcast at naturally occurring sound levels as a positive control from a drifting boat (five tag records). Time spent in foraging states and the probability of prey capture attempts were reduced during these two types of exposures with little change in overall locomotion activity, suggesting an effect on energy intake with no immediate compensation. Whales switched to the active non-foraging state over received sound pressure levels of 131-165 dB re 1 µPa during LFAS exposure. In contrast, no changes in foraging behavior were detected in response to experimental negative controls (no-sonar ship approach or noise control playback) or to experimental medium-frequency active sonar exposures (MFAS; 6-7 kHz, source level 199 re 1 µPa m, received sound pressure level [SPL] = 73-158 dB re 1 µPa). Similarly, there was no reduction in foraging effort for three whales exposed to incidental, unidentified 4.7-5.1 kHz sonar signals received at lower levels (SPL = 89-133 dB re 1 µPa). These results demonstrate that similar to predation risk, exposure to sonar can affect functional behaviors, and indicate that increased perception of risk with higher source level or lower frequency may modulate how sperm whales respond to anthropogenic sound.

Probing the critical zone using passive- and active-source estimates of subsurface shear-wave velocities

NASA Astrophysics Data System (ADS)

Callahan, R. P.; Taylor, N. J.; Pasquet, S.; Dueker, K. G.; Riebe, C. S.; Holbrook, W. S.

2016-12-01

Geophysical imaging is rapidly becoming popular for quantifying subsurface critical zone (CZ) architecture. However, a diverse array of measurements and measurement techniques are available, raising the question of which are appropriate for specific study goals. Here we compare two techniques for measuring S-wave velocities (Vs) in the near surface. The first approach quantifies Vs in three dimensions using a passive source and an iterative residual least-squares tomographic inversion. The second approach uses a more traditional active-source seismic survey to quantify Vs in two dimensions via a Monte Carlo surface-wave dispersion inversion. Our analysis focuses on three 0.01 km2 study plots on weathered granitic bedrock in the Southern Sierra Critical Zone Observatory. Preliminary results indicate that depth-averaged velocities from the two methods agree over the scales of resolution of the techniques. While the passive- and active-source techniques both quantify Vs, each method has distinct advantages and disadvantages during data acquisition and analysis. The passive-source method has the advantage of generating a three dimensional distribution of subsurface Vs structure across a broad area. Because this method relies on the ambient seismic field as a source, which varies unpredictably across space and time, data quality and depth of investigation are outside the control of the user. Meanwhile, traditional active-source surveys can be designed around a desired depth of investigation. However, they only generate a two dimensional image of Vs structure. Whereas traditional active-source surveys can be inverted quickly on a personal computer in the field, passive source surveys require significantly more computations, and are best conducted in a high-performance computing environment. We use data from our study sites to compare these methods across different scales and to explore how these methods can be used to better understand subsurface CZ architecture.

Lead exposures in U.S. Children, 2008: implications for prevention.

PubMed

Levin, Ronnie; Brown, Mary Jean; Kashtock, Michael E; Jacobs, David E; Whelan, Elizabeth A; Rodman, Joanne; Schock, Michael R; Padilla, Alma; Sinks, Thomas

2008-10-01

We reviewed the sources of lead in the environments of U.S. children, contributions to children's blood lead levels, source elimination and control efforts, and existing federal authorities. Our context is the U.S. public health goal to eliminate pediatric elevated blood lead levels (EBLs) by 2010. National, state, and local exposure assessments over the past half century have identified risk factors for EBLs among U.S. children, including age, race, income, age and location of housing, parental occupation, and season. Recent national policies have greatly reduced lead exposure among U.S. children, but even very low exposure levels compromise children's later intellectual development and lifetime achievement. No threshold for these effects has been demonstrated. Although lead paint and dust may still account for up to 70% of EBLs in U.S. children, the U.S. Centers for Disease Control and Prevention estimates that >or=30% of current EBLs do not have an immediate lead paint source, and numerous studies indicate that lead exposures result from multiple sources. EBLs and even deaths have been associated with inadequately controlled sources including ethnic remedies and goods, consumer products, and food-related items such as ceramics. Lead in public drinking water and in older urban centers remain exposure sources in many areas. Achieving the 2010 goal requires maintaining current efforts, especially programs addressing lead paint, while developing interventions that prevent exposure before children are poisoned. It also requires active collaboration across all levels of government to identify and control all potential sources of lead exposure, as well as primary prevention.

Neutron-Activated Gamma-Emission: Technology Review

DTIC Science & Technology

2012-01-01

valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) January 2012 2. REPORT TYPE Progress 3... DATES COVERED (From - To) January to March 2010 4. TITLE AND SUBTITLE Neutron-Activated Gamma-Emission: Technology Review 5a. CONTRACT NUMBER...Backscatter Analysis Techniques........................................................................13 3. Sources of Neutrons 15 3.1 Radioisotope

Controls on the Origin and Cycling of Riverine Dissolved Inorganic Carbon in the Brazos River, Texas

NASA Astrophysics Data System (ADS)

Zeng, F.; Masiello, C. A.; Hockaday, W. C.

2008-12-01

Rivers are generally supersaturated in CO2 with respect to the atmosphere. However, there is little agreement on the sources and turnover times of excess CO2 in river waters. This is likely due to varying dominant controls on carbon sources (e.g. geologic setting, climate, land use, or human activities). In this study, we measured carbon isotopic signatures (δ13C and Δ14C) of riverine dissolved inorganic carbon (DIC), as well as solid state cross polarization/magic angle spinning (CP/MAS) 13C nuclear magnetic resonance (NMR) of particulate organic carbon (POC), to determine carbon sources fuelling respiration of the Brazos River in Texas. We found that sources of riverine CO2 varied significantly along the length of the Brazos. In the middle Brazos (between Graham and Waco), which is partially underlain by limestone, riverine DIC had average Δ14C of 74 ‰ and δ13C of -7.5 ‰, suggesting that riverine CO2 is derived almost entirely from contemporary carbon (less than 5 years old) with little evidence of carbonate input, probably due to the damming upstream of Waco. In the lower Brazos (downstream of Bryan), riverine DIC was highly depleted in 14C (average Δ14C = -148.5 ‰) and enriched in 13C (average δ13C= -9.32 ‰), indicative of the presence of old carbonate. Since there is no carbonate bedrock in contact with the river in this area, the most likely source of old carbonate is the shell used in road and building construction throughout the 19th century. Our results suggest that the effect of human activities superimposes and even surpasses the effect of natural controls (e.g. geologic setting and climate) on C cycling in the Brazos.

Auditory P3a and P3b neural generators in schizophrenia: An adaptive sLORETA P300 localization approach.

PubMed

Bachiller, Alejandro; Romero, Sergio; Molina, Vicente; Alonso, Joan F; Mañanas, Miguel A; Poza, Jesús; Hornero, Roberto

2015-12-01

The present study investigates the neural substrates underlying cognitive processing in schizophrenia (Sz) patients. To this end, an auditory 3-stimulus oddball paradigm was used to identify P3a and P3b components, elicited by rare-distractor and rare-target tones, respectively. Event-related potentials (ERP) were recorded from 31 Sz patients and 38 healthy controls. The P3a and P3b brain-source generators were identified by time-averaging of low-resolution brain electromagnetic tomography (LORETA) current density images. In contrast with the commonly used fixed window of interest (WOI), we proposed to apply an adaptive WOI, which takes into account subjects' P300 latency variability. Our results showed different P3a and P3b source activation patterns in both groups. P3b sources included frontal, parietal and limbic lobes, whereas P3a response generators were localized over bilateral frontal and superior temporal regions. These areas have been related to the discrimination of auditory stimulus and to the inhibition (P3a) or the initiation (P3b) of motor response in a cognitive task. In addition, differences in source localization between Sz and control groups were observed. Sz patients showed lower P3b source activity in bilateral frontal structures and the cingulate. P3a generators were less widespread for Sz patients than for controls in right superior, medial and middle frontal gyrus. Our findings suggest that target and distractor processing involves distinct attentional subsystems, both being altered in Sz. Hence, the study of neuroelectric brain information can provide further insights to understand cognitive processes and underlying mechanisms in Sz. Copyright © 2015 Elsevier B.V. All rights reserved.

sLORETA current source density analysis of evoked potentials for spatial updating in a virtual navigation task

PubMed Central

Nguyen, Hai M.; Matsumoto, Jumpei; Tran, Anh H.; Ono, Taketoshi; Nishijo, Hisao

2014-01-01

Previous studies have reported that multiple brain regions are activated during spatial navigation. However, it is unclear whether these activated brain regions are specifically associated with spatial updating or whether some regions are recruited for parallel cognitive processes. The present study aimed to localize current sources of event related potentials (ERPs) associated with spatial updating specifically. In the control phase of the experiment, electroencephalograms (EEGs) were recorded while subjects sequentially traced 10 blue checkpoints on the streets of a virtual town, which were sequentially connected by a green line, by manipulating a joystick. In the test phase of the experiment, the checkpoints and green line were not indicated. Instead, a tone was presented when the subjects entered the reference points where they were then required to trace the 10 invisible spatial reference points corresponding to the checkpoints. The vertex-positive ERPs with latencies of approximately 340 ms from the moment when the subjects entered the unmarked reference points were significantly larger in the test than in the control phases. Current source density analysis of the ERPs by standardized low-resolution brain electromagnetic tomography (sLORETA) indicated activation of brain regions in the test phase that are associated with place and landmark recognition (entorhinal cortex/hippocampus, parahippocampal and retrosplenial cortices, fusiform, and lingual gyri), detecting self-motion (posterior cingulate and posterior insular cortices), motor planning (superior frontal gyrus, including the medial frontal cortex), and regions that process spatial attention (inferior parietal lobule). The present results provide the first identification of the current sources of ERPs associated with spatial updating, and suggest that multiple systems are active in parallel during spatial updating. PMID:24624067

Nitrite reductase expression is regulated at the post-transcriptional level by the nitrogen source in Nicotiana plumbaginifolia and Arabidopsis thaliana.

PubMed

Crété, P; Caboche, M; Meyer, C

1997-04-01

Higher plant nitrite reductase (NiR) is a monomeric chloroplastic protein catalysing the reduction of nitrite, the product of nitrate reduction, to ammonium. The expression of this enzyme is controlled at the transcriptional level by light and by the nitrogen source. In order to study the post-transcriptional regulation of NiR, Nicotiana plumbaginifolia and Arabidopsis thaliana were transformed with a chimaeric NiR construct containing the tobacco leaf NiR1 coding sequence driven by the CaMV 35S RNA promoter. Transformed plants did not show any phenotypic difference when compared with the wild-type, although they overexpressed NiR activity in the leaves. When these plants were grown in vitro on media containing either nitrate or ammonium as sole nitrogen source, NiR mRNA derived from transgene expression was constitutively expressed, whereas NiR activity and protein level were strongly reduced on ammonium-containing medium. These results suggest that, together with transcriptional control, post-transcriptional regulation by the nitrogen source is operating on NiR expression. This post-transcriptional regulation of tobacco leaf NiR1 expression was observed not only in the closely related species N. plumbaginifolia but also in the more distant species A. thaliana.

Analysis and control of computer cooling fan noise

NASA Astrophysics Data System (ADS)

Wong, Kam

This thesis is divided into three parts: the study of the source mechanisms and their separation, passive noise control, and active noise control. The mechanisms of noise radiated by a typical computer cooling fan is investigated both theoretically and experimentally focusing on the dominant rotor-stator interaction. The unsteady force generated by the aerodynamic interaction between the rotor blades and struts is phase locked with the blade rotation and radiates tonal noise. Experimentally, synchronous averaging with the rotation signal extracts the tones made by the deterministic part of the rotor-strut interaction mechanism. This averaged signal is called the rotary noise. The difference between the overall noise and rotary noise is defined as random noise which is broadband in the spectrum. The deterministic tonal peaks are certainly more annoying than the broadband, so the suppression of the tones is the focus of this study. Based on the theoretical study of point force formulation, methods are devised to separate the noise radiated by the two components of drag and thrust forces on blades and struts. The source separation is also extended to the leading and higher order modes of the spinning pressure pattern. By using the original fan rotor and installing it in various casings, the noise sources of the original fan are decomposed into elementary sources through directivity measurements. Details of the acoustical directivity for the original fan and its various modifications are interpreted. For the sample fan, two common features account for most of the tonal noise radiated. The two features are the inlet flow distortion caused by the square fan casing, and the large strut carrying the electric wires for the motor. When the inlet bellmouth is installed and the large strut is trimmed down to size, a significant reduction of 12 dB in tonal sound power is achieved. These structural corrections constitute the passive noise control. However, the end product still features the leading mode drag noise. Further reduction of this noise is left to the active noise control. The feasibility of the active noise control technique is demonstrated for the cancellation of both thrust and drag noise radiated at their leading modes. An open loop, feed-forward system is used to maximize the simplicity of the rig in order to deliver an appropriate technology for a small ventilation fan. (Abstract shortened by UMI.)

Coping with Chronic Illness in Childhood and Adolescence

PubMed Central

Compas, Bruce E.; Jaser, Sarah S.; Dunn, Madeleine J.; Rodriguez, Erin M.

2012-01-01

Chronic illnesses and medical conditions present millions of children and adolescents with significant stress that is associated with risk for emotional and behavioral problems and interferes with adherence to treatment regimens. We review research on the role of child and adolescent coping with stress as an important feature of the process of adaptation to illness. Recent findings support a control-based model of coping that includes primary control or active coping (efforts to act on the source of stress or one’s emotions), secondary control or accommodative coping (efforts to adapt to the source of stress), and disengagement or passive coping (efforts to avoid or deny the stressor). Evidence suggests the efficacy of secondary control coping in successful adaptation to chronic illness in children and adolescents, disengagement coping is associated with poorer adjustment, and findings for primary control coping are mixed. Avenues for future research are highlighted. PMID:22224836

Using spacecraft trace contaminant control systems to cure sick building syndrome

NASA Technical Reports Server (NTRS)

Graf, John C.

1994-01-01

Many residential and commercial buildings with centralized, recirculating, heating ventilation and air conditioning systems suffer from 'Sick Building Syndrome.' Ventilation rates are reduced to save energy costs, synthetic building materials off-gas contaminants, and unsafe levels of volatile organic compounds (VOC's) accumulate. These unsafe levels of contaminants can cause irritation of eyes and throat, fatigue and dizziness to building occupants. Increased ventilation, the primary method of treating Sick Building Syndrome is expensive (due to increased energy costs) and recently, the effectiveness of increased ventilation has been questioned. On spacecraft venting is not allowed, so the primary methods of air quality control are; source control, active filtering, and destruction of VOC's. Four non-venting contaminant removal technologies; strict material selection to provide source control, ambient temperature catalytic oxidation, photocatalytic oxidation, and uptake by higher plants, may have potential application for indoor air quality control.

Contamination control of the space shuttle Orbiter crew compartment

NASA Technical Reports Server (NTRS)

Bartelson, Donald W.

1986-01-01

Effective contamination control as applied to manned space flight environments is a discipline characterized and controlled by many parameters. An introduction is given to issues involving Orbiter crew compartment contamination control. An effective ground processing contamination control program is an essential building block to a successful shuttle mission. Personnel are required to don cleanroom-grade clothing ensembles before entering the crew compartment and follow cleanroom rules and regulations. Prior to crew compartment entry, materials and equipment must be checked by an orbiter integrity clerk stationed outside the white-room entrance for compliance to program requirements. Analysis and source identification of crew compartment debris studies have been going on for two years. The objective of these studies is to determine and identify particulate generating materials and activities in the crew compartment. Results show a wide spectrum of many different types of materials. When source identification is made, corrective action is implemented to minimize or curtail further contaminate generation.

Structural tuning of nanogaps using electromigration induced by field emission current with bipolar biasing

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

Yagi, Mamiko; Ito, Mitsuki; Shirakashi, Jun-ichi, E-mail: shrakash@cc.tuat.ac.jp

We report a new method for fabrication of Ni nanogaps based on electromigration induced by a field emission current. This method is called “activation” and is demonstrated here using a current source with alternately reversing polarities. The activation procedure with alternating current bias, in which the current source polarity alternates between positive and negative bias conditions, is performed with planar Ni nanogaps defined on SiO{sub 2}/Si substrates at room temperature. During negative biasing, a Fowler-Nordheim field emission current flows from the source (cathode) to the drain (anode) electrode. The Ni atoms at the tip of the drain electrode are thusmore » activated and then migrate across the gap from the drain to the source electrode. In contrast, in the positive bias case, the field emission current moves the activated atoms from the source to the drain electrode. These two procedures are repeated until the tunnel resistance of the nanogaps is successively reduced from 100 TΩ to 48 kΩ. Scanning electron microscopy and atomic force microscopy studies showed that the gap separation narrowed from approximately 95 nm to less than 10 nm because of the Ni atoms that accumulated at the tips of both the source and drain electrodes. These results show that the alternately biased activation process, which is a newly proposed atom transfer technique, can successfully control the tunnel resistance of the Ni nanogaps and is a suitable method for formation of ultrasmall nanogap structures.« less

Shear bond strength to enamel after power bleaching activated by different sources.

PubMed

Can-Karabulut, Deniz C; Karabulut, Baris

2010-01-01

The purpose of the present study was to evaluate enamel bond strength of a composite resin material after hydrogen peroxide bleaching, activated by a diode laser (LaserSmile), an ozone device (HealOzone), a light-emitting diode (BT Cool whitening system), and a quartz-Plus. Fifty extracted caries-free permanent incisors were used in this study. Thirty-eight percent hydrogen peroxidegel was applied to sound, flattened labial enamel surfaces and activated by different sources. Enamel surfaces that had received no treatment were used as control samples. Bonding agent was applied according to the manufacturer's instructions and the adhesion test was performed according to ISO/TS 11405. Statistical analysis showed significant influence of the different activation technique of hydrogen peroxide on shear bond strength to enamel (ANOVA, LSD, P < 0.05). The data in this vitro explorative study suggest the activation of hydrogen peroxide by different sources may further affect the shear bond strength of subsequent composite resin restoration to enamel. Within the limitations of this in vitro study, further studies examining the structural changes of activated hydrogen peroxide-treated enamel are needed. Due to the different activation methods; duration of light irradiation effects, longer time periods may be needed before application of adhesive restorations to enamel, compared with non-activated bleaching.

Active Noise Control for Dishwasher noise

NASA Astrophysics Data System (ADS)

Lee, Nokhaeng; Park, Youngjin

2016-09-01

The dishwasher is a useful home appliance and continually used for automatically washing dishes. It's commonly placed in the kitchen with built-in style for practicality and better use of space. In this environment, people are easily exposed to dishwasher noise, so it is an important issue for the consumers, especially for the people living in open and narrow space. Recently, the sound power levels of the noise are about 40 - 50 dBA. It could be achieved by removal of noise sources and passive means of insulating acoustical path. For more reduction, such a quiet mode with the lower speed of cycle has been introduced, but this deteriorates the washing capacity. Under this background, we propose active noise control for dishwasher noise. It is observed that the noise is propagating mainly from the lower part of the front side. Control speakers are placed in the part for the collocation. Observation part of estimating sound field distribution and control part of generating the anti-noise are designed for active noise control. Simulation result shows proposed active noise control scheme could have a potential application for dishwasher noise reduction.

Depression and anxious apprehension distinguish frontocingulate cortical activity during top-down attentional control.

PubMed

Silton, Rebecca Levin; Heller, Wendy; Engels, Anna S; Towers, David N; Spielberg, Jeffrey M; Edgar, J Christopher; Sass, Sarah M; Stewart, Jennifer L; Sutton, Bradley P; Banich, Marie T; Miller, Gregory A

2011-05-01

A network consisting of left dorsolateral prefrontal cortex (LDLPFC) and dorsal anterior cingulate cortex (dACC) has been implicated in top-down attentional control. Few studies have systematically investigated how this network is altered in psychopathology, despite evidence that depression and anxiety are associated with attentional control impairments. Functional MRI and dense-array event-related brain potential (ERP) data were collected in separate sessions from 100 participants during a color-word Stroop task. Functional MRI results guided ERP source modeling to characterize the time course of activity in LDLPFC (300-440 ms) and dACC (520-680 ms). At low levels of depression, LDLPFC activity was indirectly related to Stroop interference and only via dACC activity. In contrast, at high levels of depression, dACC did not play an intervening role, and increased LDLPFC activity was directly related to decreased Stroop interference. Specific to high levels of anxious apprehension, higher dACC activity was related to more Stroop interference. Results indicate that depression and anxious apprehension modulate temporally and functionally distinct aspects of the frontocingulate network involved in top-down attention control.

Relative Impact of Emissions Controls and Meteorology on Air Pollution Mitigation Associated with the Asia-Pacific Economic Cooperation (APEC) Conference in Beijing, China

NASA Astrophysics Data System (ADS)

Zhang, Y.; Wang, Y.; Schauer, J. J.; de Foy, B.

2016-12-01

The Beijing government and its surrounding provinces implemented a series of measures to ensure haze-free skies during the 22nd Asia-Pacific Economic Cooperation (APEC) conference (November 10th - 11th, 2014). These measures included restrictions on traffic, construction, and industrial activity. Twelve hour measurements of the concentration and composition of ambient fine particulate matter (PM2.5) were performed for 5 consecutive months near the APEC conference site before (September 11th - November 2nd, 2014), during (November 3rd - 12th, 2014) and after (November 13th, 2014 - January 31st, 2015). The measurements are used in a positive matrix factorization model to determine the contributions from seven sources of PM2.5: secondary aerosols, mobile source, industrial emission, road dust, soil dust, biomass burning and residual oil combustion. The source apportionment results are integrated with backward trajectory analysis using Weather Research and Forecast (WRF) meteorological simulations, which determine the relative influence of new regulation and meteorology upon improved air quality during the APEC conference. Data show that controls are very effective, but meteorology must be taken into account to determine the actual influence of the controls on pollution reduction. The Industry source control is the most effective for reducing concentrations, follows by secondary aerosol and biomass controls, while the least effective control is for the residual oil combustion source. The largest reductions in concentrations occur when air mass transport is from the west-northwest (Ulanqab). Secondary aerosol and mobile source reductions are most significant for air mass transport from the north-northwest (Xilingele League) origin, and least significant for northeast transport (Chifeng via Tangshan conditions). The largest reductions of soil dust, biomass burning, and industrial source are distinctly seen for Ulanqab conditions and least distinct for Xilingele League.

The role of source memory in gambling task decision making.

PubMed

Whitney, Paul; Hinson, John M

2012-01-01

The role of memory in the Iowa Gambling Task (IGT) was tested in two experiments that dissociated item memory (memory for losses obtained) from source memory (the deck that produced a given loss). In Experiment 1, participants observed 75 choices that had been made by controls or patients in previous research, followed by memory tests, and then 25 active choices from the participant. In Experiment 2, participants made choices for 75 trials, performed the memory tests, and then made 25 final choices. The data show that item and source memory can diverge within the IGT, and that source memory makes a significant contribution to IGT performance.

Final Environmental Impact Statement for Langley

NASA Technical Reports Server (NTRS)

1971-01-01

The Langley Research Center is described, together with the nature of its activities, from which it can be seen that the Center is basically not a major pollution source. Geographical, geological, and climatic charateristics of the site are also described. inasmuch as they influence both the choice of disposal methods and the environmental effects of the pollutants. The known or probable pollution sources at the Center are described. Where the intensities of these sources might exceed the recommended guide-lines, the corrective actions that have been taken or are being taken are described. The entire inventory of pollution sources and control methods is summarized in an appendix.

Model predictive direct power control for active power decoupled single-phase quasi- Z -source inverter

DOE PAGES

Liu, Yushan; Ge, Baoming; Abu-Rub, Haitham; ...

2016-06-14

In this study, the active power filter (APF) that consists of a half-bridge leg and an ac capacitor is integrated in the single-phase quasi-Z-source inverter (qZSI) in this paper to avoid the second harmonic power flowing into the dc side. The capacitor of APF buffers the second harmonic power of the load, and the ac capacitor allows highly pulsating ac voltage, so that the capacitances of both dc and ac sides can be small. A model predictive direct power control (DPC) is further proposed to achieve the purpose of this newtopology through predicting the capacitor voltage of APF at eachmore » sampling period and ensuring the APF power to track the second harmonic power of single-phase qZSI. Simulation and experimental results verify the model predictive DPC for the APF-integrated single-phase qZSI.« less

Mercury Emissions Capture Efficiency with Activated Carbon ...

EPA Pesticide Factsheets

This EPA-led project, conducted in collaboration with UNEP, the Swedish Environmental Institute and various Russian Institutes, that demonstrates that the mercury emission control efficiencies of activated carbon injection technologies applied at a Russian power plant burning Russian coals are similar to those found at U.S. plants burning US coals. (The US funding was from funds provided to the EPA by the Department of State pursuant to the Bio-Chemical Redirect Program which engages former Russian (and other former Soviet) weapons scientists in research projects with US collaborators.) Among other things, this report will aid the major task, of developing guidance on best available mercury control technology/best environmental practices (BAT/BEP) for coal-fired power plants, a major source a global anthropogenic emissions. (The new Minamata Convention requires BAT/BEP for new power plants and other major emission sources within five years of treaty ratification.)

Conjoint Analysis for New Service Development on Electricity Distribution in Indonesia

NASA Astrophysics Data System (ADS)

Widaningrum, D. L.; Chynthia; Astuti, L. D.; Seran, M. A. B.

2017-07-01

Many cases of illegal use of electricity in Indonesia is still rampant, especially for activities where the power source is not available, such as in the location of street vendors. It is not only detrimental to the state, but also harm the perpetrators of theft of electricity and the surrounding communities. The purpose of this study is to create New Service Development (NSD) to provide a new electricity source for street vendors' activity based on their preferences. The methods applied in NSD is Conjoint Analysis, Cluster Analysis, Quality Function Deployment (QFD), Service Blueprint, Process Flow Diagrams and Quality Control Plan. The results of this study are the attributes and their importance in the new electricity’s service based on street vendors’ preferences as customers, customer segmentation, service design for new service, designing technical response, designing operational procedures, the quality control plan of any existing operational procedures.

Model predictive direct power control for active power decoupled single-phase quasi- Z -source inverter

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

Liu, Yushan; Ge, Baoming; Abu-Rub, Haitham

In this study, the active power filter (APF) that consists of a half-bridge leg and an ac capacitor is integrated in the single-phase quasi-Z-source inverter (qZSI) in this paper to avoid the second harmonic power flowing into the dc side. The capacitor of APF buffers the second harmonic power of the load, and the ac capacitor allows highly pulsating ac voltage, so that the capacitances of both dc and ac sides can be small. A model predictive direct power control (DPC) is further proposed to achieve the purpose of this newtopology through predicting the capacitor voltage of APF at eachmore » sampling period and ensuring the APF power to track the second harmonic power of single-phase qZSI. Simulation and experimental results verify the model predictive DPC for the APF-integrated single-phase qZSI.« less

Application of Semi Active Control Techniques to the Damping Suppression Problem of Solar Sail Booms

NASA Technical Reports Server (NTRS)

Adetona, O.; Keel, L. H.; Whorton, M. S.

2007-01-01

Solar sails provide a propellant free form for space propulsion. These are large flat surfaces that generate thrust when they are impacted by light. When attached to a space vehicle, the thrust generated can propel the space vehicle to great distances at significant speeds. For optimal performance the sail must be kept from excessive vibration. Active control techniques can provide the best performance. However, they require an external power-source that may create significant parasitic mass to the solar sail. However, solar sails require low mass for optimal performance. Secondly, active control techniques typically require a good system model to ensure stability and performance. However, the accuracy of solar sail models validated on earth for a space environment is questionable. An alternative approach is passive vibration techniques. These do not require an external power supply, and do not destabilize the system. A third alternative is referred to as semi-active control. This approach tries to get the best of both active and passive control, while avoiding their pitfalls. In semi-active control, an active control law is designed for the system, and passive control techniques are used to implement it. As a result, no external power supply is needed so the system is not destabilize-able. Though it typically underperforms active control techniques, it has been shown to out-perform passive control approaches and can be unobtrusively installed on a solar sail boom. Motivated by this, the objective of this research is to study the suitability of a Piezoelectric (PZT) patch actuator/sensor based semi-active control system for the vibration suppression problem of solar sail booms. Accordingly, we develop a suitable mathematical and computer model for such studies and demonstrate the capabilities of the proposed approach with computer simulations.

Biological Control Potential of Bacillus amyloliquefaciens KB3 Isolated from the Feces of Allomyrina dichotoma Larvae

PubMed Central

Nam, Hyo-Song; Yang, Hyun-Ju; Oh, Byung Jun; Anderson, Anne J.; Kim, Young Cheol

2016-01-01

Most biocontrol agents for plant diseases have been isolated from sources such as soils and plants. As an alternative source, we examined the feces of tertiary larvae of the herbivorous rhino beetle, Allomyrina dichotoma for presence of biocontrol-active microbes. The initial screen was performed to detect antifungal activity against two common fungal plant pathogens. The strain with strongest antifungal activity was identified as Bacillus amyloliquefaciens KB3. The inhibitory activity of this strain correlated with lipopeptide productions, including iturin A and surfactin. Production of these surfactants in the KB3 isolate varied with the culture phase and growth medium used. In planta biocontrol activities of cell-free culture filtrates of KB3 were similar to those of the commercial biocontrol agent, B. subtilis QST-713. These results support the presence of microbes with the potential to inhibit fungal growth, such as plant pathogens, in diverse ecological niches. PMID:27298603

Changes of soil functional diversity induced by the use of different fertilizers

NASA Astrophysics Data System (ADS)

Onica, Bogdan-Mihai; Sandor, Valentina; Brad, Traian; Vidican, Roxana; Sandor, Mignon

2017-04-01

Agricultural practices like fertilization can change the structure and function of soil microbial community. Monitoring and assessing the soil microbiota and its dynamic related to different factors can be a powerful tool for understanding basic and applied ecological contexts. An important tool to assess changes of community level physiological profile is MicroResp, a colorimetric method that uses a 96-well microtitre plate, 16 carbon sources and a detection plate to quantify the respiratory activity of the soil microbial community. The main objective of this work is to assess the changes of the community level physiological profile when different fertilizers were used. In order to achieve this goal, a microcosm experiment was designed and performed under controlled temperature and humidity, and the soil samples were analyzed using the MicroResp technique. The experiment was designed with two types of soil (chernozem and luvisol), four types of fertilizers (mineral fertilizer, mustard as green manure, slurry manure and cattle manure) with three replicates for each and a control. Soil samples analyzed with MicroResp technique were prepared and loaded into the deep-well plates and incubated for six hours at 25 oC with the 15 carbon sources which were used at the concentration of 30 mg g-1 soil H2O, one in each well and water as control. The detection plates were read with a spectrophotometer before and after six hours incubation at a wavelength of 570 nm. Highest respiratory activity between the two types of soil used in experiment was given by the luvisol compared with chernozem. Regarding to the differences between the types of fertilizers, we observed that the highest microbial metabolic activity was given by green manure followed in order by cattle manure, slurry manure, control and mineral fertilizer with the lowest respiratory values. This pattern was same for both soils. However, highest respiratory activity was given by α-ketoglutaric acid, malic acid, oxalic acid, citric acid carbon sources, while the lowest respiratory activity was obtained in case of arginine.

Passive and active vibration isolation systems using inerter

NASA Astrophysics Data System (ADS)

Alujević, N.; Čakmak, D.; Wolf, H.; Jokić, M.

2018-03-01

This paper presents a theoretical study on passive and active vibration isolation schemes using inerter elements in a two degree of freedom (DOF) mechanical system. The aim of the work is to discuss basic capabilities and limitations of the vibration control systems at hand using simple and physically transparent models. Broad frequency band dynamic excitation of the source DOF is assumed. The purpose of the isolator system is to prevent vibration transmission to the receiving DOF. The frequency averaged kinetic energy of the receiving mass is used as the metric for vibration isolation quality. It is shown that the use of inerter element in the passive vibration isolation scheme can enhance the isolation effect. In the active case, a feedback disturbance rejection scheme is considered. Here, the error signal is the receiving body absolute velocity which is directly fed to a reactive force actuator between the source and the receiving bodies. In such a scheme, the so-called subcritical vibration isolation problems exist. These problems are characterised by the uncoupled natural frequency of the receiving body larger than the uncoupled natural frequency of the source body. In subcritical vibration isolation problems, the performance of the active control is limited by poor stability margins. This is because the stable feedback gain is restricted in a narrow range between a minimum and a maximum. However, with the inclusion of an inerter in the isolator, one of the two stability margins can be opened. This enables large, theoretically unlimited negative feedback gains and large active damping of the receiving body vibration. A simple expression for the required inertance is derived.

A Design Basis for Spacecraft Cabin Trace Contaminant Control

NASA Technical Reports Server (NTRS)

Perry, Jay L.

2009-01-01

Successful trace chemical contamination control is one of the components necessary for achieving good cabin atmospheric quality. While employing seemingly simple process technologies, sizing the active contamination control equipment must employ a reliable design basis for the trace chemical load in the cabin atmosphere. A simplified design basis that draws on experience gained from the International Space Station program is presented. The trace chemical contamination control design load refines generation source magnitudes and includes key chemical functional groups representing both engineering and toxicology challenges.

Area-wide management of Aedes albopictus. Part 2: gauging the efficacy of traditional integrated pest control measures against urban container mosquitoes.

PubMed

Fonseca, Dina M; Unlu, Isik; Crepeau, Taryn; Farajollahi, Ary; Healy, Sean P; Bartlett-Healy, Kristen; Strickman, Daniel; Gaugler, Randy; Hamilton, George; Kline, Daniel; Clark, Gary G

2013-12-01

Aedes (Stegomyia) albopictus (Skuse) is an important disease vector and biting nuisance. During the 2009 active season, six ∼1000-parcel sites were studied, three in urban and three in suburban areas of New Jersey, United States, to examine the efficacy of standard integrated urban mosquito control strategies applied area wide. Active source reduction, larviciding, adulticiding and public education (source reduction through education) were implemented in one site in each county, an education-only approach was developed in a second site and a third site was used as an untreated experimental control. Populations were surveyed weekly with BG-Sentinel traps and ovitraps. A substantial reduction in Ae. albopictus populations was achieved in urban sites, but only modest reductions in suburban sites. Education alone achieved significant reductions in urban adult Ae. albopictus. Egg catches echoed adult catches only in suburban sites. There are significant socioeconomic and climatic differences between urban and suburban sites that impact upon Ae. albopictus populations and the efficacy of the control methods tested. An integrated pest management approach can affect abundances, but labor-intensive, costly source reduction was not enough to maintain Ae. albopictus counts below a nuisance threshold. Nighttime adult population suppression using truck-mounted adulticides can be effective. Area-wide cost-effective strategies are necessary. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Atmospheric CO2 at Waliguan station in China: Transport climatology, temporal patterns and source-sink region representativeness

NASA Astrophysics Data System (ADS)

Cheng, Siyang; An, Xingqin; Zhou, Lingxi; Tans, Pieter P.; Jacobson, Andy

2017-06-01

In order to explore where the source and sink have the greatest impact on CO2 background concentration at Waliguan (WLG) station, a statistical method is here proposed to calculate the representative source-sink region. The key to this method is to find the best footprint threshold, and the study is carried out in four parts. Firstly, transport climatology, expressed by total monthly footprint, was simulated by FLEXPART on a 7-day time scale. Surface CO2 emissions in Eurasia frequently transported to WLG station. WLG station was mainly influenced by the westerlies in winter and partly controlled by the Southeast Asian monsoon in summer. Secondly, CO2 concentrations, simulated by CT2015, were processed and analyzed through data quality control, screening, fitting and comparing. CO2 concentrations displayed obvious seasonal variation, with the maximum and minimum concentration appearing in April and August, respectively. The correlation of CO2 fitting background concentrations was R2 = 0.91 between simulation and observation. The temporal patterns were mainly correlated with CO2 exchange of biosphere-atmosphere, human activities and air transport. Thirdly, for the monthly CO2 fitting background concentrations from CT2015, a best footprint threshold was found based on correlation analysis and numerical iteration using the data of footprints and emissions. The grid cells where monthly footprints were greater than the best footprint threshold were the best threshold area corresponding to representative source-sink region. The representative source-sink region of maximum CO2 concentration in April was primarily located in Qinghai province, but the minimum CO2 concentration in August was mainly influenced by emissions in a wider region. Finally, we briefly presented the CO2 source-sink characteristics in the best threshold area. Generally, the best threshold area was a carbon sink. The major source and sink were relatively weak owing to less human activities and vegetation types in this high altitude area. CO2 concentrations were more influenced by human activities when air mass passed through many urban areas in summer. Therefore, the combination of footprints and emissions is an effective approach for assessing the source-sink region representativeness of CO2 background concentration.

Effects of supplementation with two sources and two levels of copper on meat lipid oxidation, meat colour and superoxide dismutase and glutathione peroxidase enzyme activities in Nellore beef cattle.

PubMed

Correa, Lísia Bertonha; Zanetti, Marcus Antonio; Del Claro, Gustavo Ribeiro; de Paiva, Fernanda Alves; da Luz e Silva, Saulo; Netto, Arlindo Saran

2014-10-28

In the present study, thirty-five Nellore bulls were used to determine the effects of two levels and two sources (organic and inorganic) of Cu supplementation on the oxidative stability of lipids, measured by the thiobarbituric acid-reactive substance (TBARS) test, meat colour and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) enzyme activities. The following treatments were used: (1) control (C) - basal diet without supplementation of Cu (7 mg Cu/kg DM); (2) I10 - basal diet supplemented with 10 mg Cu/kg DM in the form of copper sulphate (inorganic form); (3) I40 - basal diet supplemented with 40 mg Cu/kg DM in the form of copper sulphate; (4) O10 - basal diet supplemented with 10 mg Cu/kg DM in the form of copper proteinate (organic form); (5) O40 - basal diet supplemented with 40 mg Cu/kg DM in the form of copper proteinate. Lipid oxidation was determined in meat samples exposed to display, modified atmosphere (MA) and vacuum packaging (VC) conditions and in liver samples using the TBARS test. These samples were also evaluated for meat discolouration after exposure to air. The activities of SOD and GSH-Px enzymes were determined in liver samples. In display, MA and VC conditions, the TBARS values of samples from animals supplemented with 40 mg Cu/kg DM were lower than those of samples from control animals. There was no effect of treatment on the colour variables (L*, a*, b*). There was also no significant effect of treatment on hepatic TBARS concentrations and GSH-Px activity. Supplementation with Cu at 40 mg/kg, regardless of the source, induced higher hepatic SOD activity compared with the control treatment. In conclusion, Cu supplementation improved the oxidative stability of lipids in samples exposed to display, MA and VC conditions, demonstrating the antioxidant effect of this mineral.

The time course of activity in dorsolateral prefrontal cortex and anterior cingulate cortex during top-down attentional control.

PubMed

Silton, Rebecca Levin; Heller, Wendy; Towers, David N; Engels, Anna S; Spielberg, Jeffrey M; Edgar, J Christopher; Sass, Sarah M; Stewart, Jennifer L; Sutton, Bradley P; Banich, Marie T; Miller, Gregory A

2010-04-15

A network of brain regions has been implicated in top-down attentional control, including left dorsolateral prefrontal cortex (LDLPFC) and dorsal anterior cingulate cortex (dACC). The present experiment evaluated predictions of the cascade-of-control model (Banich, 2009), which predicts that during attentionally-demanding tasks, LDLPFC imposes a top-down attentional set which precedes late-stage selection performed by dACC. Furthermore, the cascade-of-control model argues that dACC must increase its activity to compensate when top-down control by LDLPFC is poor. The present study tested these hypotheses using fMRI and dense-array ERP data collected from the same 80 participants in separate sessions. fMRI results guided ERP source modeling to characterize the time course of activity in LDLPFC and dACC. As predicted, dACC activity subsequent to LDLPFC activity distinguished congruent and incongruent conditions on the Stroop task. Furthermore, when LDLPFC activity was low, the level of dACC activity was related to performance outcome. These results demonstrate that dACC responds to attentional demand in a flexible manner that is dependent on the level of LDLPFC activity earlier in a trial. Overall, results were consistent with the temporal course of regional brain function proposed by the cascade-of-control model. Copyright 2009 Elsevier Inc. All rights reserved.

Luminopsins integrate opto- and chemogenetics by using physical and biological light sources for opsin activation

PubMed Central

Berglund, Ken; Clissold, Kara; Li, Haofang E.; Wen, Lei; Park, Sung Young; Gleixner, Jan; Klein, Marguerita E.; Lu, Dongye; Barter, Joseph W.; Rossi, Mark A.; Augustine, George J.; Yin, Henry H.; Hochgeschwender, Ute

2016-01-01

Luminopsins are fusion proteins of luciferase and opsin that allow interrogation of neuronal circuits at different temporal and spatial resolutions by choosing either extrinsic physical or intrinsic biological light for its activation. Building on previous development of fusions of wild-type Gaussia luciferase with channelrhodopsin, here we expanded the utility of luminopsins by fusing bright Gaussia luciferase variants with either channelrhodopsin to excite neurons (luminescent opsin, LMO) or a proton pump to inhibit neurons (inhibitory LMO, iLMO). These improved LMOs could reliably activate or silence neurons in vitro and in vivo. Expression of the improved LMO in hippocampal circuits not only enabled mapping of synaptic activation of CA1 neurons with fine spatiotemporal resolution but also could drive rhythmic circuit excitation over a large spatiotemporal scale. Furthermore, virus-mediated expression of either LMO or iLMO in the substantia nigra in vivo produced not only the expected bidirectional control of single unit activity but also opposing effects on circling behavior in response to systemic injection of a luciferase substrate. Thus, although preserving the ability to be activated by external light sources, LMOs expand the use of optogenetics by making the same opsins accessible to noninvasive, chemogenetic control, thereby allowing the same probe to manipulate neuronal activity over a range of spatial and temporal scales. PMID:26733686

Diagnostics for Hypersonic Engine Control

DTIC Science & Technology

2015-02-01

modeling efforts and/or lead to the development of sensors that can be used as part of scramjet engine control strategies. Activities included work on...of a model scramjet engine cannot rely on the presence of water. Instead, light sources operating at wavelengths resonant with molecular oxygen are...transmitted beam amplitude fluctuations (scintillation). Frequency axis is normalized. Figure 3. Oxygen absorption feature recorded using direct

Active Control of the Forced and Transient Response of a Finite Beam. M.S. Thesis

NASA Technical Reports Server (NTRS)

Post, John Theodore

1989-01-01

When studying structural vibrations resulting from a concentrated source, many structures may be modelled as a finite beam excited by a point source. The theoretical limit on cancelling the resulting beam vibrations by utilizing another point source as an active controller is explored. Three different types of excitation are considered, harmonic, random, and transient. In each case, a cost function is defined and minimized for numerous parameter variations. For the case of harmonic excitation, the cost function is obtained by integrating the mean squared displacement over a region of the beam in which control is desired. A controller is then found to minimize this cost function in the control interval. The control interval and controller location are continuously varied for several frequencies of excitation. The results show that control over the entire beam length is possible only when the excitation frequency is near a resonant frequency of the beam, but control over a subregion may be obtained even between resonant frequencies at the cost of increasing the vibration outside of the control region. For random excitation, the cost function is realized by integrating the expected value of the displacement squared over the interval of the beam in which control is desired. This is shown to yield the identical cost function as obtained by integrating the cost function for harmonic excitation over all excitation frequencies. As a result, it is always possible to reduce the cost function for random excitation whether controlling the entire beam or just a subregion, without ever increasing the vibration outside the region in which control is desired. The last type of excitation considered is a single, transient pulse. A cost function representative of the beam vibration is obtained by integrating the transient displacement squared over a region of the beam and over all time. The form of the controller is chosen a priori as either one or two delayed pulses. Delays constrain the controller to be causal. The best possible control is then examined while varying the region of control and the controller location. It is found that control is always possible using either one or two control pulses. The two pulse controller gives better performance than a single pulse controller, but finding the optimal delay time for the additional controllers increases as the square of the number of control pulses.

Understanding narrative effects in physical activity promotion: the influence of breast cancer survivor testimony on exercise beliefs, self-efficacy, and intention in breast cancer patients.

PubMed

Falzon, Charlène; Radel, Rémi; Cantor, Ambre; d'Arripe-Longueville, Fabienne

2015-03-01

Research in health communication has shown that narratives contribute more positively to changing health behaviors than informational messages. The main purposes of this study were to examine and to compare the effects of two messages promoting physical activity, one narrative and the other informational, on the perceptions and behavioral intentions of cancer patients. A total of 158 women with breast cancer, undergoing chemotherapy and sedentary, were assigned to read the testimony of a breast cancer survivor who had been physically active during and after treatment (TE group), a content-equivalent message composed of expert recommendations about physical activity in breast cancer patients (RE group), or no message (control group). Source trust was higher in TE group than RE group (p < 0.001). Exercise self-efficacy and exercise intention were higher in TE group than RE and control groups (p < 0.001). However, scores in RE group were higher than those of TE group for beliefs about exercise benefits (p < 0.001) and lower than those of TE and control groups for beliefs about exercise risks (p < 0.001). Source trust, exercise self-efficacy, and beliefs about exercise benefits and risks mediated the relationship between the message and exercise intention. The results suggest that narratives may be more effective in improving perceived physical abilities and involvement in physical activity, whereas informational messages seem to be more appropriate to convey the benefits and the absence of risks related to physical activity.

Payload/orbiter contamination control requirement study

NASA Technical Reports Server (NTRS)

Bareiss, L. E.; Rantanen, R. O.; Ress, E. B.

1974-01-01

A study was conducted to determine and quantify the expected particulate and molecular on-orbit contaminant environment for selected space shuttle payloads as a result of major shuttle orbiter contamination sources. Individual payload susceptibilities to contamination are reviewed. The risk of payload degradation is identified and preliminary recommendations are provided concerning the limiting factors which may depend on operational activities associated with the payload/orbiter interface or upon independent payload functional activities. A basic computer model of the space shuttle orbiter which includes a representative payload configuration is developed. The major orbiter contamination sources, locations, and flux characteristics based upon available data have been defined and modeled.

MHC class I target recognition, immunophenotypes and proteomic profiles of natural killer cells within the spleens of day-14 chick embryos

USDA-ARS?s Scientific Manuscript database

Chicken natural killer (NK) cells are not well defined, so little is known about the molecular interactions controlling their activity. At day 14 of embryonic development, chick spleens are a rich source of T-cellfree CD8aa+, CD3_ cells with natural killing activity. Cell-mediated cytotoxicity assay...

Top-Down Control of Visual Alpha Oscillations: Sources of Control Signals and Their Mechanisms of Action

PubMed Central

Wang, Chao; Rajagovindan, Rajasimhan; Han, Sahng-Min; Ding, Mingzhou

2016-01-01

Alpha oscillations (8–12 Hz) are thought to inversely correlate with cortical excitability. Goal-oriented modulation of alpha has been studied extensively. In visual spatial attention, alpha over the region of visual cortex corresponding to the attended location decreases, signifying increased excitability to facilitate the processing of impending stimuli. In contrast, in retention of verbal working memory, alpha over visual cortex increases, signifying decreased excitability to gate out stimulus input to protect the information held online from sensory interference. According to the prevailing model, this goal-oriented biasing of sensory cortex is effected by top-down control signals from frontal and parietal cortices. The present study tests and substantiates this hypothesis by (a) identifying the signals that mediate the top-down biasing influence, (b) examining whether the cortical areas issuing these signals are task-specific or task-independent, and (c) establishing the possible mechanism of the biasing action. High-density human EEG data were recorded in two experimental paradigms: a trial-by-trial cued visual spatial attention task and a modified Sternberg working memory task. Applying Granger causality to both sensor-level and source-level data we report the following findings. In covert visual spatial attention, the regions exerting top-down control over visual activity are lateralized to the right hemisphere, with the dipoles located at the right frontal eye field (FEF) and the right inferior frontal gyrus (IFG) being the main sources of top-down influences. During retention of verbal working memory, the regions exerting top-down control over visual activity are lateralized to the left hemisphere, with the dipoles located at the left middle frontal gyrus (MFG) being the main source of top-down influences. In both experiments, top-down influences are mediated by alpha oscillations, and the biasing effect is likely achieved via an inhibition-disinhibition mechanism. PMID:26834601

Carbon Catabolite Repression and Impranil Polyurethane Degradation in Pseudomonas protegens Strain Pf-5.

PubMed

Hung, Chia-Suei; Zingarelli, Sandra; Nadeau, Lloyd J; Biffinger, Justin C; Drake, Carrie A; Crouch, Audra L; Barlow, Daniel E; Russell, John N; Crookes-Goodson, Wendy J

2016-10-15

Polyester polyurethane (PU) coatings are widely used to help protect underlying structural surfaces but are susceptible to biological degradation. PUs are susceptible to degradation by Pseudomonas species, due in part to the degradative activity of secreted hydrolytic enzymes. Microorganisms often respond to environmental cues by secreting enzymes or secondary metabolites to benefit their survival. This study investigated the impact of exposing several Pseudomonas strains to select carbon sources on the degradation of the colloidal polyester polyurethane Impranil DLN (Impranil). The prototypic Pseudomonas protegens strain Pf-5 exhibited Impranil-degrading activities when grown in sodium citrate but not in glucose-containing medium. Glucose also inhibited the induction of Impranil-degrading activity by citrate-fed Pf-5 in a dose-dependent manner. Biochemical and mutational analyses identified two extracellular lipases present in the Pf-5 culture supernatant (PueA and PueB) that were involved in degradation of Impranil. Deletion of the pueA gene reduced Impranil-clearing activities, while pueB deletion exhibited little effect. Removal of both genes was necessary to stop degradation of the polyurethane. Bioinformatic analysis showed that putative Cbr/Hfq/Crc-mediated regulatory elements were present in the intergenic sequences upstream of both pueA and pueB genes. Our results confirmed that both PueA and PueB extracellular enzymes act in concert to degrade Impranil. Furthermore, our data showed that carbon sources in the growth medium directly affected the levels of Impranil-degrading activity but that carbon source effects varied among Pseudomonas strains. This study uncovered an intricate and complicated regulation of P. protegens PU degradation activity controlled by carbon catabolite repression. Polyurethane (PU) coatings are commonly used to protect metals from corrosion. Microbiologically induced PU degradation might pose a substantial problem for the integrity of these coatings. Microorganisms from diverse genera, including pseudomonads, possess the ability to degrade PUs via various means. This work identified two extracellular lipases, PueA and PueB, secreted by P. protegens strain Pf-5, to be responsible for the degradation of a colloidal polyester PU, Impranil. This study also revealed that the expression of the degradative activity by strain Pf-5 is controlled by glucose carbon catabolite repression. Furthermore, this study showed that the Impranil-degrading activity of many other Pseudomonas strains could be influenced by different carbon sources. This work shed light on the carbon source regulation of PU degradation activity among pseudomonads and identified the polyurethane lipases in P. protegens. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Carbon Catabolite Repression and Impranil Polyurethane Degradation in Pseudomonas protegens Strain Pf-5

PubMed Central

Hung, Chia-Suei; Zingarelli, Sandra; Nadeau, Lloyd J.; Biffinger, Justin C.; Drake, Carrie A.; Crouch, Audra L.; Barlow, Daniel E.; Russell, John N.

2016-01-01

ABSTRACT Polyester polyurethane (PU) coatings are widely used to help protect underlying structural surfaces but are susceptible to biological degradation. PUs are susceptible to degradation by Pseudomonas species, due in part to the degradative activity of secreted hydrolytic enzymes. Microorganisms often respond to environmental cues by secreting enzymes or secondary metabolites to benefit their survival. This study investigated the impact of exposing several Pseudomonas strains to select carbon sources on the degradation of the colloidal polyester polyurethane Impranil DLN (Impranil). The prototypic Pseudomonas protegens strain Pf-5 exhibited Impranil-degrading activities when grown in sodium citrate but not in glucose-containing medium. Glucose also inhibited the induction of Impranil-degrading activity by citrate-fed Pf-5 in a dose-dependent manner. Biochemical and mutational analyses identified two extracellular lipases present in the Pf-5 culture supernatant (PueA and PueB) that were involved in degradation of Impranil. Deletion of the pueA gene reduced Impranil-clearing activities, while pueB deletion exhibited little effect. Removal of both genes was necessary to stop degradation of the polyurethane. Bioinformatic analysis showed that putative Cbr/Hfq/Crc-mediated regulatory elements were present in the intergenic sequences upstream of both pueA and pueB genes. Our results confirmed that both PueA and PueB extracellular enzymes act in concert to degrade Impranil. Furthermore, our data showed that carbon sources in the growth medium directly affected the levels of Impranil-degrading activity but that carbon source effects varied among Pseudomonas strains. This study uncovered an intricate and complicated regulation of P. protegens PU degradation activity controlled by carbon catabolite repression. IMPORTANCE Polyurethane (PU) coatings are commonly used to protect metals from corrosion. Microbiologically induced PU degradation might pose a substantial problem for the integrity of these coatings. Microorganisms from diverse genera, including pseudomonads, possess the ability to degrade PUs via various means. This work identified two extracellular lipases, PueA and PueB, secreted by P. protegens strain Pf-5, to be responsible for the degradation of a colloidal polyester PU, Impranil. This study also revealed that the expression of the degradative activity by strain Pf-5 is controlled by glucose carbon catabolite repression. Furthermore, this study showed that the Impranil-degrading activity of many other Pseudomonas strains could be influenced by different carbon sources. This work shed light on the carbon source regulation of PU degradation activity among pseudomonads and identified the polyurethane lipases in P. protegens. PMID:27496773

Activation patterns in superficial layers of neocortex change between experiences independent of behavior, environment, or the hippocampus.

PubMed

Takehara-Nishiuchi, Kaori; Insel, Nathan; Hoang, Lan T; Wagner, Zachary; Olson, Kathy; Chawla, Monica K; Burke, Sara N; Barnes, Carol A

2013-09-01

Previous work suggests that activation patterns of neurons in superficial layers of the neocortex are more sensitive to spatial context than activation patterns in deep cortical layers. A possible source of this laminar difference is the distribution of contextual information to the superficial cortical layers carried by hippocampal efferents that travel through the entorhinal cortex and subiculum. To evaluate the role that the hippocampus plays in determining context sensitivity in superficial cortical layers, behavior-induced expression of the immediate early gene Arc was examined in hippocampus-lesioned and control rats after exposing them to 2 distinct contexts. Contrary to expectations, hippocampal lesions had no observable effect on Arc expression in any neocortical layer relative to controls. Furthermore, another group of intact animals was exposed to the same environment twice, to determine the reliability of Arc-expression patterns across identical contextual and behavioral episodes. Although this condition included no difference in external input between 2 epochs, the significant layer differences in Arc expression still remained. Thus, laminar differences in activation or plasticity patterns are not likely to arise from hippocampal sources or differences in external inputs, but are more likely to be an intrinsic property of the neocortex.

Beam wavefront and farfield control for ICF laser driver

NASA Astrophysics Data System (ADS)

Dai, Wanjun; Deng, Wu; Zhang, Xin; Jiang, Xuejun; Zhang, Kun; Zhou, Wei; Zhao, Junpu; Hu, Dongxia

2010-10-01

Five main problems of beam wavefront and farfield control in ICF laser driver are synthetically discussed, including control requirements, beam propagation principle, distortions source control, system design and adjustment optimization, active wavefront correction technology. We demonstrate that beam can be propagated well and the divergence angle of the TIL pulses can be improved to less than 60μrad with solving these problems, which meets the requirements of TIL. The results can provide theoretical and experimental support for wavefront and farfield control designing requirements of the next large scale ICF driver.

40 CFR 122.27 - Silvicultural activities (applicable to State NPDES programs, see § 123.25).

Code of Federal Regulations, 2010 CFR

2010-07-01

..., prescribed burning, pest and fire control, harvesting operations, surface drainage, or road construction and... roads) may involve point source discharges of dredged or fill material which may require a CWA section...

Noise pollution resources compendium

NASA Technical Reports Server (NTRS)

1973-01-01

Abstracts of reports concerning noise pollution are presented. The abstracts are grouped in the following areas of activity: (1) sources of noise, (2) noise detection and measurement, (3) noise abatement and control, (4) physical effects of noise and (5) social effects of noise.

[Active surveillance of adverse drug reaction in the era of big data: challenge and opportunity for control selection].

PubMed

Wang, S F; Zhan, S Y

2016-07-01

Electronic healthcare databases have become an important source for active surveillance of drug safety in the era of big data. The traditional epidemiology research designs are needed to confirm the association between drug use and adverse events based on these datasets, and the selection of the comparative control is essential to each design. This article aims to explain the principle and application of each type of control selection, introduce the methods and parameters for method comparison, and describe the latest achievements in the batch processing of control selection, which would provide important methodological reference for the use of electronic healthcare databases to conduct post-marketing drug safety surveillance in China.

Multi-Frequency Microwaves Plasma Production for Active Profile Control of Ion Beams on a Large Bore ECR Ion Source with Permanent Magnets

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

Sakamoto, Naoki; Kato, Yushi; Kiriyama, Ryutaro

2011-01-07

A new concept on magnetic field of plasma production and confinement by using permanent magnets, i.e. cylindrically comb-shaped magnets, has been proposed to enhance efficiency of an electron cyclotron resonance (ECR) plasma for broad and dense ion beam source under the low pressure and also the low microwave power. The resonance zones corresponding to the fundamental ECR for 2.45 GHz and 11-13 GHz frequency are constructed at different positions. The profiles of the plasma parameters in the ECR ion source are different from each frequency of microwave. Large bore extractor is set at the opposite side against the microwave feeds.more » It is found that differences of their profiles also appear at those of ion beam profiles. We conducted to launch simultaneously multiplex frequency microwaves controlled individually, and tried to control the profiles of the plasma parameters and then those of extracted ion beam.« less

The Basal Ganglia Striosomes Affect the Modulation of Conflicts by Subliminal Information-Evidence from X-Linked Dystonia Parkinsonism.

PubMed

Beste, Christian; Mückschel, Moritz; Rosales, Raymond; Domingo, Aloysius; Lee, Lillian; Ng, Arlene; Klein, Christine; Münchau, Alexander

2018-07-01

Cognitive control is relevant when distracting information induces behavioral conflicts. Such conflicts can be produced consciously and by subliminally processed information. Interestingly, both sources of conflict interact suggesting that they share neural mechanisms. Here, we ask whether conjoint effects between different sources of conflict are modulated by microstructural basal ganglia dysfunction. To this end, we carried out an electroencephalography study and examined event-related potentials (ERPs) including source localization using a combined flanker-subliminal priming task in patients with X-linked dystonia Parkinsonism (XDP) and a group of healthy controls. XDP in its early stages is known to predominantly affect the basal ganglia striosomes. The results suggest that conjoint effects between subliminal and conscious sources of conflicts are modulated by the striosomes and were stronger in XDP patients. The neurophysiological data indicate that this effect is related to modulations in conflict monitoring and response selection (N2 ERP) mechanisms engaging the anterior cingulate cortex. Bottom-up perceptual gating, attentional selection, and motor response activation processes in response to the stimuli (P1, N1, and lateralized readiness potential ERPs) were unaffected. Taken together, these data indicate that striosomes modulate the processing of conscious and subliminal sources of conflict suggesting that microstructural basal ganglia properties are relevant for cognitive control.

Behavioral Science as a New Frontier for Transformational ...

EPA Pesticide Factsheets

Over the last 40 years, tremendous progress has been made toward protecting our life-sustaining resources of air, water, and land and improving ecosystems and public health despite increasing population pressures. Many disciplines have provided the scientific underpinnings for this progress, but perhaps none have been more influential than exposure science. Exposure science has fostered a receptor- rather than source-based perspective regarding strategies for monitoring and controlling pollution to protect public health and the environment. We have achieved many gains through control of far-field sources. Near-field sources related to consumer products and activities in the home, vehicle, school, and work environments present the next challenge. These near-field sources tend to dominate our exposures and are direct results of our behaviors in purchasing and using consumer products. Therefore, these types of sources are less amenable to traditional regulatory approaches for exposure reduction. Behavior determines not only the presence or absence of consumer product and use, but also the details that largely define critical chemical exposure metrics including amount, concentration, frequency, duration, and pathway of exposure. Thus, it is becoming increasingly evident that in order to both predict and control near-field chemical exposures, we need to better understand human behavior and the knowledge, attitudes and beliefs that underlie consumer product rel

Nonpoint source pollution of urban stormwater runoff: a methodology for source analysis.

PubMed

Petrucci, Guido; Gromaire, Marie-Christine; Shorshani, Masoud Fallah; Chebbo, Ghassan

2014-09-01

The characterization and control of runoff pollution from nonpoint sources in urban areas are a major issue for the protection of aquatic environments. We propose a methodology to quantify the sources of pollutants in an urban catchment and to analyze the associated uncertainties. After describing the methodology, we illustrate it through an application to the sources of Cu, Pb, Zn, and polycyclic aromatic hydrocarbons (PAH) from a residential catchment (228 ha) in the Paris region. In this application, we suggest several procedures that can be applied for the analysis of other pollutants in different catchments, including an estimation of the total extent of roof accessories (gutters and downspouts, watertight joints and valleys) in a catchment. These accessories result as the major source of Pb and as an important source of Zn in the example catchment, while activity-related sources (traffic, heating) are dominant for Cu (brake pad wear) and PAH (tire wear, atmospheric deposition).

Footwall degradation styles and associated sedimentary facies distribution in SE Crete: Insights into tilt-block extensional basins on continental margins

NASA Astrophysics Data System (ADS)

Alves, Tiago M.; Cupkovic, Tomas

2018-05-01

Depositional facies resulting from footwall degradation in extensional basins of SE Crete are studied based on detailed geological maps, regional transects, lithological columns and outcrop photos. During an extensional episode affecting Crete in the late Miocene-early Pliocene, depocentres trending N20°E and N70°E were filled with fan deltas, submarine mass-wasting deposits, sandy turbidites and fine-grained hemipelagites sourced from both nearby and distal sediment sources. Deposition of proximal continental and shallow-marine units, and relatively deep (marine) turbidites and mass-transport deposits, occurred within a complex mosaic of tectonically controlled depocentres. The new geological maps and transects in this work reveal that depositional facies in SE Crete were controlled by: a) their relative proximity to active faults and uplifting footwall blocks, b) the relative position (depth and relative height above sea level) of hanging-wall basins, and c) the nature of the basement units eroded from adjacent footwall blocks. Distal sediment sources supplied background siliciclastic sediment ('hemipelagites'), which differ markedly from strata sourced from local footwalls. In parallel, mass-transport of sediment was ubiquitous on tectonically active slopes, and so was the presence of coarse-grained sediment with sizes varying from large blocks > 50 m-wide to heterolithic mass-transport deposits and silty-sandy turbidites. We expect similar tectono-sedimentary settings to have predominated in tectonically active Miocene basins of the eastern Mediterranean, in which hydrocarbon exploration is occurring at present, and on rifted continental margins across the world.

EEG background activity is abnormal in the temporal and inferior parietal cortex in benign rolandic epilepsy of childhood: a LORETA study.

PubMed

Besenyei, M; Varga, E; Fekete, I; Puskás, S; Hollódy, K; Fogarasi, A; Emri, M; Opposits, G; Kis, S A; Clemens, B

2012-01-01

Benign rolandic epilepsy of childhood (BERS) is an epilepsy syndrome with presumably genetic-developmental etiology. The pathological basis of this syndrome is completely unknown. We postulated that a developmental abnormality presumably results in abnormal EEG background activity findings. 20 children with typical BERS and an age- and sex-matched group of healthy control children underwent EEG recording and analysis. 60×2 s epochs of waking EEG background activity (without epileptiform potentials and artifacts) were analyzed in the 1-25 Hz frequency range, in very narrow bands (VNB, 1 Hz bandwidth). LORETA (Low Resolution Electromagnetic Tomography) localized multiple distributed sources of EEG background activity in the Talairach space. LORETA activity (current source density) was computed for 2394 voxels and 25 VNBs. Normalized LORETA data were processed to voxel-wise comparison between the BERS and control groups. Bonferroni-corrected p<0.05 Student's t-values were accepted as statistically significant. Increased LORETA activity was found in the BERS group (as compared to the controls) in the left and right temporal lobes (fusiform gyri, posterior parts of the superior, middle and inferior temporal gyri) and in the angular gyri in the parietal lobes, in the 4-6 Hz VNBs, mainly at 5 Hz. (1) Areas of abnormal LORETA activity exactly correspond to the temporal and parietal cortical areas that are major components of the Mirsky attention model and also the perisylvian speech network. Thus the LORETA findings may correspond to impaired attention and speech in BERS patients. (2) The LORETA findings may contribute to delineating the epileptic network in BERS. The novel findings may contribute to investigating neuropsychological disturbances and organization of the epileptic network in BERS. Copyright © 2011 Elsevier B.V. All rights reserved.

Environmental Verification Experiment for the Explorer Platform (EVEEP)

NASA Technical Reports Server (NTRS)

Norris, Bonnie; Lorentson, Chris

1992-01-01

Satellites and long-life spacecraft require effective contamination control measures to ensure data accuracy and maintain overall system performance margins. Satellite and spacecraft contamination can occur from either molecular or particulate matter. Some of the sources of the molecular species are as follows: mass loss from nonmetallic materials; venting of confined spacecraft or experiment volumes; exhaust effluents from attitude control systems; integration and test activities; and improper cleaning of surfaces. Some of the sources of particulates are as follows: leaks or purges which condense upon vacuum exposure; abrasion of movable surfaces; and micrometeoroid impacts. The Environmental Verification Experiment for the Explorer Platform (EVEEP) was designed to investigate the following aspects of spacecraft contamination control: materials selection; contamination modeling of existing designs; and thermal vacuum testing of a spacecraft with contamination monitors.

A Systematic Review of Surgical Randomized Controlled Trials: Part 2. Funding Source, Conflict of Interest, and Sample Size in Plastic Surgery.

PubMed

Voineskos, Sophocles H; Coroneos, Christopher J; Ziolkowski, Natalia I; Kaur, Manraj N; Banfield, Laura; Meade, Maureen O; Chung, Kevin C; Thoma, Achilleas; Bhandari, Mohit

2016-02-01

The authors examined industry support, conflict of interest, and sample size in plastic surgery randomized controlled trials that compared surgical interventions. They hypothesized that industry-funded trials demonstrate statistically significant outcomes more often, and randomized controlled trials with small sample sizes report statistically significant results more frequently. An electronic search identified randomized controlled trials published between 2000 and 2013. Independent reviewers assessed manuscripts and performed data extraction. Funding source, conflict of interest, primary outcome direction, and sample size were examined. Chi-squared and independent-samples t tests were used in the analysis. The search identified 173 randomized controlled trials, of which 100 (58 percent) did not acknowledge funding status. A relationship between funding source and trial outcome direction was not observed. Both funding status and conflict of interest reporting improved over time. Only 24 percent (six of 25) of industry-funded randomized controlled trials reported authors to have independent control of data and manuscript contents. The mean number of patients randomized was 73 per trial (median, 43, minimum, 3, maximum, 936). Small trials were not found to be positive more often than large trials (p = 0.87). Randomized controlled trials with small sample size were common; however, this provides great opportunity for the field to engage in further collaboration and produce larger, more definitive trials. Reporting of trial funding and conflict of interest is historically poor, but it greatly improved over the study period. Underreporting at author and journal levels remains a limitation when assessing the relationship between funding source and trial outcomes. Improved reporting and manuscript control should be goals that both authors and journals can actively achieve.

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

Simpson, L.; Britt, J.; Birkmire, R.

ITN Energy Systems, Inc., and Global Solar Energy, Inc., assisted by NREL's PV Manufacturing R&D program, have continued to advance CIGS production technology by developing trajectory-oriented predictive/control models, fault-tolerance control, control platform development, in-situ sensors, and process improvements. Modeling activities included developing physics-based and empirical models for CIGS and sputter-deposition processing, implementing model-based control, and applying predictive models to the construction of new evaporation sources and for control. Model-based control is enabled by implementing reduced or empirical models into a control platform. Reliability improvement activities include implementing preventive maintenance schedules; detecting failed sensors/equipment and reconfiguring to tinue processing; and systematicmore » development of fault prevention and reconfiguration strategies for the full range of CIGS PV production deposition processes. In-situ sensor development activities have resulted in improved control and indicated the potential for enhanced process status monitoring and control of the deposition processes. Substantial process improvements have been made, including significant improvement in CIGS uniformity, thickness control, efficiency, yield, and throughput. In large measure, these gains have been driven by process optimization, which in turn have been enabled by control and reliability improvements due to this PV Manufacturing R&D program.« less

Ferric Citrate Controls Phosphorus and Delivers Iron in Patients on Dialysis

PubMed Central

Sika, Mohammed; Koury, Mark J.; Chuang, Peale; Schulman, Gerald; Smith, Mark T.; Whittier, Frederick C.; Linfert, Douglas R.; Galphin, Claude M.; Athreya, Balaji P.; Nossuli, A. Kaldun Kaldun; Chang, Ingrid J.; Blumenthal, Samuel S.; Manley, John; Zeig, Steven; Kant, Kotagal S.; Olivero, Juan Jose; Greene, Tom; Dwyer, Jamie P.

2015-01-01

Patients on dialysis require phosphorus binders to prevent hyperphosphatemia and are iron deficient. We studied ferric citrate as a phosphorus binder and iron source. In this sequential, randomized trial, 441 subjects on dialysis were randomized to ferric citrate or active control in a 52-week active control period followed by a 4-week placebo control period, in which subjects on ferric citrate who completed the active control period were rerandomized to ferric citrate or placebo. The primary analysis compared the mean change in phosphorus between ferric citrate and placebo during the placebo control period. A sequential gatekeeping strategy controlled study-wise type 1 error for serum ferritin, transferrin saturation, and intravenous iron and erythropoietin-stimulating agent usage as prespecified secondary outcomes in the active control period. Ferric citrate controlled phosphorus compared with placebo, with a mean treatment difference of −2.2±0.2 mg/dl (mean±SEM) (P<0.001). Active control period phosphorus was similar between ferric citrate and active control, with comparable safety profiles. Subjects on ferric citrate achieved higher mean iron parameters (ferritin=899±488 ng/ml [mean±SD]; transferrin saturation=39%±17%) versus subjects on active control (ferritin=628±367 ng/ml [mean±SD]; transferrin saturation=30%±12%; P<0.001 for both). Subjects on ferric citrate received less intravenous elemental iron (median=12.95 mg/wk ferric citrate; 26.88 mg/wk active control; P<0.001) and less erythropoietin-stimulating agent (median epoetin-equivalent units per week: 5306 units/wk ferric citrate; 6951 units/wk active control; P=0.04). Hemoglobin levels were statistically higher on ferric citrate. Thus, ferric citrate is an efficacious and safe phosphate binder that increases iron stores and reduces intravenous iron and erythropoietin-stimulating agent use while maintaining hemoglobin. PMID:25060056

Vegetation and other development options for mitigating urban air pollution impacts

EPA Science Inventory

In addition to installing air pollution control devices and reducing emissions activities, urban air pollution can be further mitigated through planning and design strategies including vegetation planting, building design, installing roadside and near source structures, and modif...

Activated sludge is a potential source for production of biodegradable plastics from wastewater.

PubMed

Khardenavis, A; Guha, P K; Kumar, M S; Mudliar, S N; Chakrabarti, T

2005-05-01

Increased utilization of synthetic plastics caused severe environmental pollution due to their non-biodegradable nature. In the search for environmentally friendly materials to substitute for conventional plastics, different biodegradable plastics have been developed by microbial fermentations. However, limitations of these materials still exist due to high cost. This study aims at minimization of cost for the production of biodegradable plastics P(3HB) and minimization of environmental pollution. The waste biological sludge generated at wastewater treatment plants is used for the production of P(3HB) and wastewater is used as carbon source. Activated sludge was induced by controlling the carbon: nitrogen ratio to accumulate storage polymer. Initially polymer accumulation was studied by using different carbon and nitrogen sources. Maximum accumulation of polymer was observed with carbon source acetic acid and diammonium hydrogen phosphate (DAHP) as nitrogen source. Further studies were carried out to optimize the carbon: nitrogen ratios using acetic acid and DAHP. A maximum of 65.84% (w/w) P(3HB) production was obtained at C/N ratio of 50 within 96 hours of incubation.

Renewable Molecular Flasks with NADH Models: Combination of Light-Driven Proton Reduction and Biomimetic Hydrogenation of Benzoxazinones.

PubMed

Zhao, Liang; Wei, Jianwei; Lu, Junhua; He, Cheng; Duan, Chunying

2017-07-17

Using small molecules with defined pockets to catalyze chemical transformations resulted in attractive catalytic syntheses that echo the remarkable properties of enzymes. By modulating the active site of a nicotinamide adenine dinucleotide (NADH) model in a redox-active molecular flask, we combined biomimetic hydrogenation with in situ regeneration of the active site in a one-pot transformation using light as a clean energy source. This molecular flask facilitates the encapsulation of benzoxazinones for biomimetic hydrogenation of the substrates within the inner space of the flask using the active sites of the NADH models. The redox-active metal centers provide an active hydrogen source by light-driven proton reduction outside the pocket, allowing the in situ regeneration of the NADH models under irradiation. This new synthetic platform, which offers control over the location of the redox events, provides a regenerating system that exhibits high selectivity and efficiency and is extendable to benzoxazinone and quinoxalinone systems. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

PubMed

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

2018-04-01

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

Biofiltration: an innovative air pollution control technology for VOC emissions.

PubMed

Leson, G; Winer, A M

1991-08-01

Biofiltration is a relatively recent air pollution control (APC) technology in which off-gases containing biodegradable volatile organic compounds (VOC) or inorganic air toxics are vented through a biologically active material. This technology has been successfully applied in Germany and The Netherlands in many full-scale applications to control odors, VOC and air toxic emissions from a wide range of industrial and public sector sources. Control efficiencies of more than 90 percent have been achieved for many common air pollutants. Due to lower operating costs, biofiltration can provide significant economic advantages over other APC technologies if applied to off-gases that contain readily biodegradable pollutants in low concentrations. Environmental benefits include low energy requirements and the avoidance of cross media transfer of pollutants. This paper reviews the history and current status of biofiltration, outlines its underlying scientific and engineering principles, and discusses the applicability of biofilters for a wide range of specific emission sources.

Source apportionment of PM2.5 for supporting control strategies in the Monterrey Metropolitan Area, Mexico.

PubMed

Martínez-Cinco, Marco; Santos-Guzmán, Jesús; Mejía-Velázquez, Gerardo

2016-06-01

The Monterrey Metropolitan Area (MMA) in Northeast Mexico has shown high PM2.5 concentrations since 2003. The data shows that the annual average concentration exceeds from 2 to 3 times the Mexican PM2.5 annual air quality standard of 12 µg/m(3). In a previous work we studied the chemical characterization of PM2.5 in two sites of the MMA during the winter season. Among the most important components we found ammonium sulfate and nitrate, elemental and organic carbon, and crustal matter. In this work we present the results of a second chemical characterization study performed during the summer time and the application of the chemical mass balance (CMB) model to determine the source apportionment of air pollutants in the region. The chemical analysis results show that the chemical composition of PM2.5 is similar in both sites and periods of the year. The results of the chemical analysis and the CMB model show that industrial, traffic, and combustion activities in the area are the major sources of primary PM2.5 and precursor gases of secondary inorganic and organic aerosol (SO2, NOx, NH3, and volatile organic compounds [VOCs]). We also found that black carbon and organic carbon are important components of PM2.5 in the MMA. These results are consistent with the MMA emission inventory that reports as major sources of particles and SO2 a refinery and fuel combustion, as well as nitrogen oxides and ammonium from transportation and industrial activities in the MMA and ammonium form agricultural activities in the state. The results of this work are important to identify and support effective actions to reduce direct emissions of PM2.5 and its precursor gases to improve air quality in the MMA. The Monterrey Metropolitan Area (MMA) has been classified as the most air-polluted area in Mexico by the World Health Organization (WHO). Effective actions need to be taken to control primary sources of PM2.5 and its precursors, reducing health risks on the population exposed and their associated costs. The results of this study identify the main sources and their estimated contribution to PM2.5 mass concentration, providing valuable information to the local environmental authorities to take decisions on PM2.5 control strategies in the MMA.

The congestion control algorithm based on queue management of each node in mobile ad hoc networks

NASA Astrophysics Data System (ADS)

Wei, Yifei; Chang, Lin; Wang, Yali; Wang, Gaoping

2016-12-01

This paper proposes an active queue management mechanism, considering the node's own ability and its importance in the network to set the queue threshold. As the network load increases, local congestion of mobile ad hoc network may lead to network performance degradation, hot node's energy consumption increase even failure. If small energy nodes congested because of forwarding data packets, then when it is used as the source node will cause a lot of packet loss. This paper proposes an active queue management mechanism, considering the node's own ability and its importance in the network to set the queue threshold. Controlling nodes buffer queue in different levels of congestion area probability by adjusting the upper limits and lower limits, thus nodes can adjust responsibility of forwarding data packets according to their own situation. The proposed algorithm will slow down the send rate hop by hop along the data package transmission direction from congestion node to source node so that to prevent further congestion from the source node. The simulation results show that, the algorithm can better play the data forwarding ability of strong nodes, protect the weak nodes, can effectively alleviate the network congestion situation.

Variable Frequency Diverter Actuation for Flow Control

NASA Technical Reports Server (NTRS)

Culley, Dennis E.

2006-01-01

The design and development of an actively controlled fluidic actuator for flow control applications is explored. The basic device, with one input and two output channels, takes advantage of the Coanda effect to force a fluid jet to adhere to one of two axi-symmetric surfaces. The resultant flow is bi-stable, producing a constant flow from one output channel, until a disturbance force applied at the control point causes the flow to switch to the alternate output channel. By properly applying active control the output flows can be manipulated to provide a high degree of modulation over a wide and variable range of frequency and duty cycle. In this study the momentary operative force is applied by small, high speed isolation valves of which several different types are examined. The active fluidic diverter actuator is shown to work in several configurations including that in which the operator valves are referenced to atmosphere as well as to a source common with the power stream.

Supramolecular Approaches to Nanoscale Morphological Control in Organic Solar Cells

PubMed Central

Haruk, Alexander M.; Mativetsky, Jeffrey M.

2015-01-01

Having recently surpassed 10% efficiency, solar cells based on organic molecules are poised to become a viable low-cost clean energy source with the added advantages of mechanical flexibility and light weight. The best-performing organic solar cells rely on a nanostructured active layer morphology consisting of a complex organization of electron donating and electron accepting molecules. Although much progress has been made in designing new donor and acceptor molecules, rational control over active layer morphology remains a central challenge. Long-term device stability is another important consideration that needs to be addressed. This review highlights supramolecular strategies for generating highly stable nanostructured organic photovoltaic active materials by design. PMID:26110382

The Quabbin controlled deer hunt 1991 - 2001: limitations of a controlled hunt

Treesearch

Beth E. Cohen; David K. Loomis

2003-01-01

The Quabbin Reservoir, built in the 1930's as a water supply for Boston, is an unfiltered source of water. The agency responsible for managing the reservoir wants it to remain unfiltered. As a result, human activity is kept to a minimum, including (until recently) a prohibition on hunting. The lack of natural predators and the ban on recreational hunting allowed...

Integrated Broadband Quantum Cascade Laser

NASA Technical Reports Server (NTRS)

Mansour, Kamjou (Inventor); Soibel, Alexander (Inventor)

2016-01-01

A broadband, integrated quantum cascade laser is disclosed, comprising ridge waveguide quantum cascade lasers formed by applying standard semiconductor process techniques to a monolithic structure of alternating layers of claddings and active region layers. The resulting ridge waveguide quantum cascade lasers may be individually controlled by independent voltage potentials, resulting in control of the overall spectrum of the integrated quantum cascade laser source. Other embodiments are described and claimed.

Plastic waste in the marine environment: A review of sources, occurrence and effects.

PubMed

Li, W C; Tse, H F; Fok, L

2016-10-01

This review article summarises the sources, occurrence, fate and effects of plastic waste in the marine environment. Due to its resistance to degradation, most plastic debris will persist in the environment for centuries and may be transported far from its source, including great distances out to sea. Land- and ocean-based sources are the major sources of plastic entering the environment, with domestic, industrial and fishing activities being the most important contributors. Ocean gyres are particular hotspots of plastic waste accumulation. Both macroplastics and microplastics pose a risk to organisms in the natural environment, for example, through ingestion or entanglement in the plastic. Many studies have investigated the potential uptake of hydrophobic contaminants, which can then bioaccumulate in the food chain, from plastic waste by organisms. To address the issue of plastic pollution in the marine environment, governments should first play an active role in addressing the issue of plastic waste by introducing legislation to control the sources of plastic debris and the use of plastic additives. In addition, plastics industries should take responsibility for the end-of-life of their products by introducing plastic recycling or upgrading programmes. Copyright © 2016 Elsevier B.V. All rights reserved.

Human mesenchymal stem cells generate a distinct pericellular zone of MMP activities via binding of MMPs and secretion of high levels of TIMPs.

PubMed

Lozito, Thomas P; Jackson, Wesley M; Nesti, Leon J; Tuan, Rocky S

2014-02-01

Mesenchymal stem cells (MSCs) are attractive candidates for inclusion in cell-based therapies by virtue of their abilities to home to wound sites. However, in-depth characterization of the specific effects of MSCs on their microenvironments is needed to realize their full therapeutic potentials. Furthermore, since MSCs of varying properties can be isolated from a diverse spectrum of tissues, a strategic and rational approach in MSC sourcing for a particular application has yet to be achieved. For example, MSCs that activate their proteolytic environments may promote tissue remodeling, while those from different tissue sources may inhibit proteases and promote tissue stabilization. This study attempts to address these issues by analyzing MSCs isolated from three adult tissue sources in terms of their effects on their proteolytic microenvironments. Human bone marrow, adipose, and traumatized muscle derived MSCs were compared in their soluble and cellular-associated MMP components and activity. For all types of MSCs, MMP activity associated with the cell surface, but activity levels and MMP profiles differed with tissue source. All MSC types bound exogenous active MMPs at their surfaces. MSCs were also able to activate exogenous proMMP-2 and proMMP-13. This is in marked contrast to the MSC soluble compartment, which strongly inhibited MMPs via endogenous TIMPs. The exact TIMP used to inhibit the exogenous MMP differed with MSC type. Thus, MSCs saturate their environment with both MMPs and TIMPs. Since they bind and activate MMPs at their surfaces, the net result is a very controlled pericellular localization of MMP activities by MSCs. © 2013.

Chemical constituents and their acetyl cholinesterase inhibitory and antioxidant activities from leaves of Acanthopanax henryi: potential complementary source against Alzheimer's disease.

PubMed

Zhang, Xiao Dan; Liu, Xiang Qian; Kim, Yang Hee; Whang, Wan Kyunn

2014-05-01

The aim of this study was to investigate chemical constituents of the leaves of Acanthopanax henryi, and their antioxidant, acetyl cholinesterase inhibitory activities. Caffeoyl quinic acid derivates and flavonoids were obtained from A. henry, through column chromatography technologies, and the content of major constituents was determined by the HPLC-UV method. Anti-oxidant activity of the isolated metabolites was evaluated by free radical scavenging (DPPH, ABTS radicals) and superoxide anion scavenging. The results showed that di-caffeoyl quinic acid derivates had stronger antioxidant activity than positive controls (ascorbic acid, trolox and allopurinol). Acetyl cholinesterase inhibitory activity was estimated on the constituents, among which, quercetin, 4-caffeoyl-quinic acid and 4,5-caffeoyl quinic acid were found to have strong acetyl cholinesterase inhibitory activity with IC50 values ranging from 62.6 to 121.9 μM. The present study showed that some of the tested constituents from the leaves of A. henryi exhibit strong antioxidant and acetyl cholinesterase inhibitory effects. This suggest that the leaves of A. henryi can be used as a new natural complementary source of acetyl cholinesterase inhibitors and anti-oxidant agents, thus being a promising potential complementary source against Alzheimer's disease.

The Effect of Defense R&D Expenditures on Military Capability and Technological Spillover

DTIC Science & Technology

2013-03-01

ix List of Figures Page Figure 1. Decision Tree for Sectoring R&D Units...approach, often called sectoring , categorizes R&D activities by funding source, and the functional approach categorizes R&D activities by their objective...economic objectives (defense, and control and care of environment) (OECD, 2002). Figure 1 shows the decision tree for sectoring R&D units and

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

PubMed

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

2016-07-01

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

Development of a (147)Pm source for beta-backscatter thickness gauge applications.

PubMed

Kumar, Manoj; Udhayakumar, J; Nuwad, J; Shukla, Rakesh; Pillai, C G S; Dash, Ashutosh; Venkatesh, Meera

2011-03-01

This paper describes a method for the preparation of (147)Pm sources, utilized in the determination of graphite coating thickness on the inner surface of the zircaloy cladding tube of nuclear fuels. (147)Pm was adsorbed on a limited surface area [1.5mm (ϕ)×2mm (l)] of a cylindrical aluminum rod [1.5mm (ϕ)×10mm (l)]. In brief, the selected tip area [1.5mm (ϕ)×2mm (l)] was anodized at a current density of 15mA/cm(2) at 15°C in 3M·H(2)SO(4) for 2h followed by immersion of this area in 10μL of (147)Pm solution containing 37MBq (1mCi) of activity at pH 6.0 for 24h. The radioactive area was subsequently covered with a thin layer of Polymethyl Methacrylate (PMMA) to prevent leaching of (147)Pm from the source. The quantity of incorporated (147)Pm activity was assayed in a calibrated ion chamber. Quality control tests were carried out to ensure nonleachability, uniform distribution of activity and stability of the sources. Copyright © 2010 Elsevier Ltd. All rights reserved.

Tuberculosis outbreak investigation of a U.S. Navy amphibious ship crew and the Marine expeditionary unit aboard, 1998.

PubMed

Lamar, James E; Malakooti, Mark A

2003-07-01

A Marine deployed aboard a U.S. Navy amphibious ship had smear-positive, cavitary pulmonary tuberculosis (TB). Contact investigation ultimately found 21 active cases of TB among sailors and Marines who were aboard the affected ship. Approximately 3 months lapsed between onset of the source patient's illness and appropriate diagnosis and treatment. During the contact investigation, 3,338 persons received tuberculin skin tests and 712 were identified as new latent tuberculosis infection cases. Four persons diagnosed with latent tuberculosis infection developed active TB because of poor compliance with treatment. After personnel disembarked from the ship, persistent efforts to identify persons with active disease and latent infections were successful in controlling further spread of tuberculosis in military units and local communities. The Mycobacterium tuberculosis bacteria isolated from the source patient and 16 of the other active cases were susceptible to all drugs commonly used to treat TB.

Antioxidant activities of crude phlorotannins from Sargassum hemiphyllum.

PubMed

Zhao, Zhi-Li; Yang, Xiao-Qing; Gong, Zhong-Qing; Pan, Ming-Zhu; Han, Ya-Li; Liu, Yi

2016-06-01

Brown algae are well known as a source of biologically active compounds, especially those having antioxidant activities, such as phlorotannins. In this study we examined the antioxidant activities of crude phlorotannins extracts (CPEs) obtained from Sargassum hemiphyllum (SH) and fractionated according to the molecular weights. When CPEs were administrated at a dose of 30 mg/kg to Kunming mice pre-treated with carbon tetrachloride (CCl4), the levels of oxidative stress indicators in the liver, kidney and brain were significantly reduced in vivo. All the components of various molecular weight fractions of CPEs exhibited greater scavenging capacities in clearing hydroxyl free radical and superoxide anion than the positive controls gallic acid, vitamin C and vitamin E. Particularly, the components greater than 30 kD obtained from ethyl acetate phase showed the highest antioxidant capacities. These results indicated that SH is a potential source for extracting phlorotannins, the algal antioxidant compounds.

Active control of thermoacoustic amplification in a thermo-acousto-electric engine

NASA Astrophysics Data System (ADS)

Olivier, Come; Penelet, Guillaume; Poignand, Gaelle; Lotton, Pierrick

2014-05-01

In this paper, a new approach is proposed to control the operation of a thermoacoustic Stirling electricity generator. This control basically consists in adding an additional acoustic source to the device, connected through a feedback loop to a reference microphone, a phase-shifter, and an audio amplifier. Experiments are performed to characterize the impact of the feedback loop (and especially that of the controlled phase-shift) on the overall efficiency of the thermal to electric energy conversion performed by the engine. It is demonstrated that this external forcing of thermoacoustic self-sustained oscillations strongly impacts the performance of the engine, and that it is possible under some circumstances to improve the efficiency of the thermo-electric transduction, compared to the one reached without active control. Applicability and further directions of investigation are also discussed.

OpenNFT: An open-source Python/Matlab framework for real-time fMRI neurofeedback training based on activity, connectivity and multivariate pattern analysis.

PubMed

Koush, Yury; Ashburner, John; Prilepin, Evgeny; Sladky, Ronald; Zeidman, Peter; Bibikov, Sergei; Scharnowski, Frank; Nikonorov, Artem; De Ville, Dimitri Van

2017-08-01

Neurofeedback based on real-time functional magnetic resonance imaging (rt-fMRI) is a novel and rapidly developing research field. It allows for training of voluntary control over localized brain activity and connectivity and has demonstrated promising clinical applications. Because of the rapid technical developments of MRI techniques and the availability of high-performance computing, new methodological advances in rt-fMRI neurofeedback become possible. Here we outline the core components of a novel open-source neurofeedback framework, termed Open NeuroFeedback Training (OpenNFT), which efficiently integrates these new developments. This framework is implemented using Python and Matlab source code to allow for diverse functionality, high modularity, and rapid extendibility of the software depending on the user's needs. In addition, it provides an easy interface to the functionality of Statistical Parametric Mapping (SPM) that is also open-source and one of the most widely used fMRI data analysis software. We demonstrate the functionality of our new framework by describing case studies that include neurofeedback protocols based on brain activity levels, effective connectivity models, and pattern classification approaches. This open-source initiative provides a suitable framework to actively engage in the development of novel neurofeedback approaches, so that local methodological developments can be easily made accessible to a wider range of users. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Design and vibration control of vehicle engine mount activated by MR fluid and piezoelectric actuator

NASA Astrophysics Data System (ADS)

Lee, D. Y.; Park, Y. K.; Choi, S. B.; Lee, H. G.

2009-07-01

An engine is one of the most dominant noise and vibration sources in vehicle systems. Therefore, in order to resolve noise and vibration problems due to engine, various types of engine mounts have been proposed. This work presents a new type of active engine mount system featuring a magneto-rheological (MR) fluid and a piezostack actuator. As a first step, six degrees-of freedom dynamic model of an in-line four-cylinder engine which has three points mounting system is derived by considering the dynamic behaviors of MR mount and piezostack mount. In the configuration of engine mount system, two MR mounts are installed for vibration control of roll mode motion whose energy is very high in low frequency range, while one piezostack mount is installed for vibration control of bounce and pitch mode motion whose energy is relatively high in high frequency range. As a second step, linear quadratic regulator (LQR) controller is synthesized to actively control the imposed vibration. In order to demonstrate the effectiveness of the proposed active engine mount, vibration control performances are evaluated under various engine operating speeds (wide frequency range).

Bio-inspired Computing for Robots

NASA Technical Reports Server (NTRS)

Laufenberg, Larry

2003-01-01

Living creatures may provide algorithms to enable active sensing/control systems in robots. Active sensing could enable planetary rovers to feel their way in unknown environments. The surface of Jupiter's moon Europa consists of fractured ice over a liquid sea that may contain microbes similar to those on Earth. To explore such extreme environments, NASA needs robots that autonomously survive, navigate, and gather scientific data. They will be too far away for guidance from Earth. They must sense their environment and control their own movements to avoid obstacles or investigate a science opportunity. To meet this challenge, CICT's Information Technology Strategic Research (ITSR) Project is funding neurobiologists at NASA's Jet Propulsion Laboratory (JPL) and selected universities to search for biologically inspired algorithms that enable robust active sensing and control for exploratory robots. Sources for these algorithms are living creatures, including rats and electric fish.

Dissociable neural mechanisms underlying response-based and familiarity-based conflict in working memory.

PubMed

Nelson, James K; Reuter-Lorenz, Patricia A; Sylvester, Ching-Yune C; Jonides, John; Smith, Edward E

2003-09-16

Cognitive control requires the resolution of interference among competing and potentially conflicting representations. Such conflict can emerge at different points between stimulus input and response generation, with the net effect being that of compromising performance. The goal of this article was to dissociate the neural mechanisms underlying different sources of conflict to elucidate the architecture of the neural systems that implement cognitive control. By using functional magnetic resonance imaging and a verbal working memory task (item recognition), we examined brain activity related to two kinds of conflict with comparable behavioral consequences. In a trial of our item-recognition task, participants saw four letters, followed by a retention interval, and a probe letter that did or did not match one of the letters held in working memory (positive probe and negative probe, respectively). On some trials, conflict arose solely because of the current negative probe having a high familiarity, due to its membership in the immediately preceding trial's target set. On other trials, additional conflict arose because of the current negative probe having also been a positive probe on the immediately preceding trial, producing response-level conflict. Consistent with previous work, conflict due to high familiarity was associated with left prefrontal activation, but not with anterior cingulate activation. The response-conflict condition, when compared with high-familiarity conflict trials, was associated with anterior cingulate cortex activation, but with no additional left prefrontal activation. This double dissociation points to differing contributions of specific cortical areas to cognitive control, which are based on the source of conflict.

Efforts to reduce exposure at Japanese PWRs: CVCS improvement

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

Terada, Ryosuke

1995-03-01

Many reports have been focused on the reduction of radiation sources and related occupational exposures. The radiation sources mainly consist of corrosion products. Radiation dose rate is determined by the amount of the activated corrosion products on the surface of the primary loop components of Pressurized Water Reactor (PWR) plants. Therefore, reducing the amount of the corrosion product will contribute to the reduction of occupational exposures. In order to reduce the corrosion products, Chemical and Volume Control System (CVCS) has been improved in Japanese PWRs as follows: (a) Cation Bed Demineralizer Flowrate Control; (b) Hydrogen Peroxide Injection System; (c) Purificationmore » Flowrate During Plant Shutdown; (d) Fine Mesh Filters Upstream of Mixed Bed Demineralizers.« less

QPA-CLIPS: A language and representation for process control

NASA Technical Reports Server (NTRS)

Freund, Thomas G.

1994-01-01

QPA-CLIPS is an extension of CLIPS oriented towards process control applications. Its constructs define a dependency network of process actions driven by sensor information. The language consists of three basic constructs: TASK, SENSOR, and FILTER. TASK's define the dependency network describing alternative state transitions for a process. SENSOR's and FILTER's define sensor information sources used to activate state transitions within the network. Deftemplate's define these constructs and their run-time environment is an interpreter knowledge base, performing pattern matching on sensor information and so activating TASK's in the dependency network. The pattern matching technique is based on the repeatable occurrence of a sensor data pattern. QPA-CIPS has been successfully tested on a SPARCStation providing supervisory control to an Allen-Bradley PLC 5 controller driving molding equipment.

Abnormalities of P300 before and after antidepressant treatment in depression: an ERP-sLORETA study.

PubMed

Zhou, Lina; Wang, Gaohua; Wang, Huiling

2018-02-07

Despite a wide range of reports on depression-induced P300 changes, it is still debatable whether P300 can return to a pattern characteristic of healthy individuals following antidepressant treatment. Thus, the present study aims to compare P300 and its underlying neural activation in depressed patients before and after antidepressant treatment to explore the brain regions related to pathogenesis and to evaluate the prognosis after treatment. P300 was evoked by the oddball auditory paradigm and collected from 14 sex-matched, age-matched, and education level-matched patients and controls. P300 was also collected in the same patients after treatment. sLORETA was used to explore the source activation of P300 components. Depressed patients before and after antidepressant treatment tended to show lower P300 amplitudes compared with healthy controls, and their P300 amplitudes of F3 electrodes were correlated negatively to their scores on the 24-item Hamilton Depression Rating Scale, the Snaith-Hamilton Pleasure Scale, and the nine-item Patient Health Questionnaire. P300 amplitudes of P4 electrodes were correlated negatively with their scores on the Dysfunctional Attitude Scale. P300 source activation of depressed patients before antidepressant treatment was reduced in the left superior parietal lobule and the precuneus compared with healthy controls and depressed patients after treatment. No difference was found between healthy controls and depressed patients after treatment. The left superior parietal lobule and the precuneus might be therapeutic targets of depression.

Silica exposure during construction activities: statistical modeling of task-based measurements from the literature.

PubMed

Sauvé, Jean-François; Beaudry, Charles; Bégin, Denis; Dion, Chantal; Gérin, Michel; Lavoué, Jérôme

2013-05-01

Many construction activities can put workers at risk of breathing silica containing dusts, and there is an important body of literature documenting exposure levels using a task-based strategy. In this study, statistical modeling was used to analyze a data set containing 1466 task-based, personal respirable crystalline silica (RCS) measurements gathered from 46 sources to estimate exposure levels during construction tasks and the effects of determinants of exposure. Monte-Carlo simulation was used to recreate individual exposures from summary parameters, and the statistical modeling involved multimodel inference with Tobit models containing combinations of the following exposure variables: sampling year, sampling duration, construction sector, project type, workspace, ventilation, and controls. Exposure levels by task were predicted based on the median reported duration by activity, the year 1998, absence of source control methods, and an equal distribution of the other determinants of exposure. The model containing all the variables explained 60% of the variability and was identified as the best approximating model. Of the 27 tasks contained in the data set, abrasive blasting, masonry chipping, scabbling concrete, tuck pointing, and tunnel boring had estimated geometric means above 0.1mg m(-3) based on the exposure scenario developed. Water-fed tools and local exhaust ventilation were associated with a reduction of 71 and 69% in exposure levels compared with no controls, respectively. The predictive model developed can be used to estimate RCS concentrations for many construction activities in a wide range of circumstances.

Controlled release of molecular components of dendrimer/bioactive complexes

DOEpatents

Segalman, Daniel J.; Wallace, J. Shield

1998-01-01

A method for releasing molecules (guest molecules) from the matrix formed by the structure of another molecule (host molecule) in a controllable manner has been invented. This method has many applications in science and industry. In addition, applications based on such molecular systems may revolutionize significant areas of medicine, in particular the treatment of cancer and of viral infection. Similar effects can also be obtained by controlled fragmentation of a source molecule, where the molecular fragments form the active principle.

Controlled release of molecular components of dendrimer/bioactive complexes

DOEpatents

Segalman, D.J.; Wallace, J.S.

1998-08-18

A method for releasing molecules (guest molecules) from the matrix formed by the structure of another molecule (host molecule) in a controllable manner has been invented. This method has many applications in science and industry. In addition, applications based on such molecular systems may revolutionize significant areas of medicine, in particular the treatment of cancer and of viral infection. Similar effects can also be obtained by controlled fragmentation of a source molecule, where the molecular fragments form the active principle. 13 figs.

The Pseudomonas aeruginosa Catabolite Repression Control Protein Crc Is Devoid of RNA Binding Activity

PubMed Central

Djinovic-Carugo, Kristina; Bläsi, Udo

2013-01-01

The Crc protein has been shown to mediate catabolite repression control in Pseudomonas, leading to a preferential assimilation of carbon sources. It has been suggested that Crc acts as a translational repressor of mRNAs, encoding functions involved in uptake and breakdown of different carbon sources. Moreover, the regulatory RNA CrcZ, the level of which is increased in the presence of less preferred carbon sources, was suggested to bind to and sequester Crc, resulting in a relief of catabolite repression. Here, we determined the crystal structure of Pseudomonas aeruginosa Crc, a member of apurinic/apyrimidinic (AP) endonuclease family, at 1.8 Å. Although Crc displays high sequence similarity with its orthologs, there are amino acid alterations in the area corresponding to the active site in AP proteins. Unlike typical AP endonuclease family proteins, Crc has a reduced overall positive charge and the conserved positively charged amino-acid residues of the DNA-binding surface of AP proteins are partially substituted by negatively charged, polar and hydrophobic residues. Crc protein purified to homogeneity from P. aeruginosa did neither display DNase activity, nor did it bind to previously identified RNA substrates. Rather, the RNA chaperone Hfq was identified as a contaminant in His-tagged Crc preparations purified by one step Ni-affinity chromatography from Escherichia coli, and was shown to account for the RNA binding activity observed with the His-Crc preparations. Taken together, these data challenge a role of Crc as a direct translational repressor in carbon catabolite repression in P. aeruginosa. PMID:23717639

The Pseudomonas aeruginosa catabolite repression control protein Crc is devoid of RNA binding activity.

PubMed

Milojevic, Tetyana; Grishkovskaya, Irina; Sonnleitner, Elisabeth; Djinovic-Carugo, Kristina; Bläsi, Udo

2013-01-01

The Crc protein has been shown to mediate catabolite repression control in Pseudomonas, leading to a preferential assimilation of carbon sources. It has been suggested that Crc acts as a translational repressor of mRNAs, encoding functions involved in uptake and breakdown of different carbon sources. Moreover, the regulatory RNA CrcZ, the level of which is increased in the presence of less preferred carbon sources, was suggested to bind to and sequester Crc, resulting in a relief of catabolite repression. Here, we determined the crystal structure of Pseudomonas aeruginosa Crc, a member of apurinic/apyrimidinic (AP) endonuclease family, at 1.8 Å. Although Crc displays high sequence similarity with its orthologs, there are amino acid alterations in the area corresponding to the active site in AP proteins. Unlike typical AP endonuclease family proteins, Crc has a reduced overall positive charge and the conserved positively charged amino-acid residues of the DNA-binding surface of AP proteins are partially substituted by negatively charged, polar and hydrophobic residues. Crc protein purified to homogeneity from P. aeruginosa did neither display DNase activity, nor did it bind to previously identified RNA substrates. Rather, the RNA chaperone Hfq was identified as a contaminant in His-tagged Crc preparations purified by one step Ni-affinity chromatography from Escherichia coli, and was shown to account for the RNA binding activity observed with the His-Crc preparations. Taken together, these data challenge a role of Crc as a direct translational repressor in carbon catabolite repression in P. aeruginosa.

A single-phase multi-level D-STATCOM inverter using modular multi-level converter (MMC) topology for renewable energy sources

NASA Astrophysics Data System (ADS)

Sotoodeh, Pedram

This dissertation presents the design of a novel multi-level inverter with FACTS capability for small to mid-size (10-20kW) permanent-magnet wind installations using modular multi-level converter (MMC) topology. The aim of the work is to design a new type of inverter with D-STATCOM option to provide utilities with more control on active and reactive power transfer of distribution lines. The inverter is placed between the renewable energy source, specifically a wind turbine, and the distribution grid in order to fix the power factor of the grid at a target value, regardless of wind speed, by regulating active and reactive power required by the grid. The inverter is capable of controlling active and reactive power by controlling the phase angle and modulation index, respectively. The unique contribution of the proposed work is to combine the two concepts of inverter and D-STATCOM using a novel voltage source converter (VSC) multi-level topology in a single unit without additional cost. Simulations of the proposed inverter, with 5 and 11 levels, have been conducted in MATLAB/Simulink for two systems including 20 kW/kVAR and 250 W/VAR. To validate the simulation results, a scaled version (250 kW/kVAR) of the proposed inverter with 5 and 11 levels has been built and tested in the laboratory. Experimental results show that the reduced-scale 5- and 11-level inverter is able to fix PF of the grid as well as being compatible with IEEE standards. Furthermore, total cost of the prototype models, which is one of the major objectives of this research, is comparable with market prices.

Site-controlled crystalline InN growth from the V-pits of a GaN substrate

NASA Astrophysics Data System (ADS)

Kuo, Chien-Ting; Hsu, Lung-Hsing; Lai, Yung-Yu; Cheng, Shan-Yun; Kuo, Hao-Chung; Lin, Chien-Chung; Cheng, Yuh-Jen

2017-05-01

A site-controlled crystalline InN growth from the V-pits of a GaN substrate was investigated. The V- pits were fabricated by epitaxial lateral growth of GaN over SiO2 disks patterned on a sapphire substrate. InN crystals were found to preferably grow on the inclined {10-11} crystal planes of the V-pits. A V-pit size of 1 μm or less can provide precise site-controlled InN nucleation at the V-pit bottom, while no InN was grown on the rest of the exposed GaN surfaces. The site-controlled nucleation is attributed to the low surface energy point created by the converging six {10-11} crystal facets at the V-pit bottom. When In source supply is below a certain value, this V-pit bottom is the only location able to aggregate enough active sources to start nucleation, thereby providing site-controlled crystal growth.

Activated platelets are the source of elevated levels of soluble CD40 ligand in the circulation of inflammatory bowel disease patients.

PubMed

Danese, S; Katz, J A; Saibeni, S; Papa, A; Gasbarrini, A; Vecchi, M; Fiocchi, C

2003-10-01

The CD40/CD40L system, a key regulator and amplifier of immune reactivity, is activated in inflammatory bowel disease (IBD) mucosa. To determine whether plasma levels of sCD40L are elevated in Crohn's disease (CD) and ulcerative colitis (UC) patients compared with normal controls, to investigate the cellular source of sCD40L, and to explore CD40L induction mechanisms. CD, UC, and normal control subjects were studied. The concentration of sCD40L in plasma and supernatants of freshly isolated platelets and autologous peripheral blood T cells (PBT) was measured by ELISA. Surface CD40L expression level was measured by flow cytometry in resting and thrombin activated platelets, and unstimulated and CD3/CD28 stimulated PBT before and after coculture with human intestinal microvascular endothelial cells (HIMEC). Compared with normal controls, plasma sCD40L levels were significantly higher in both CD and UC patients and proportional to the extent of mucosal inflammation. Platelets from IBD patients displayed a significantly higher surface CD40L expression than those from control subjects, and released greater amounts of sCD40L than autologous PBT. Contact with IL-1beta activated HIMEC induced significant upregulation of CD40L surface expression and release by platelets. Elevated levels of sCD40L in the circulation of IBD patients reflect enhanced surface expression and release of CD40L by platelets. This phenomenon translates to an increased platelet activation state apparently induced by passage through an inflamed mucosal microvascular bed, a conclusion supported by the positive correlation of plasma sCD40L levels with the extent of anatomical involvement by IBD. These results suggest that platelet-endothelial interactions critically contribute to activation of the CD40 pathway in IBD.

Air-coupled acoustic thermography for in-situ evaluation

NASA Technical Reports Server (NTRS)

Zalameda, Joseph N. (Inventor); Winfree, William P. (Inventor); Yost, William T. (Inventor)

2010-01-01

Acoustic thermography uses a housing configured for thermal, acoustic and infrared radiation shielding. For in-situ applications, the housing has an open side adapted to be sealingly coupled to a surface region of a structure such that an enclosed chamber filled with air is defined. One or more acoustic sources are positioned to direct acoustic waves through the air in the enclosed chamber and towards the surface region. To activate and control each acoustic source, a pulsed signal is applied thereto. An infrared imager focused on the surface region detects a thermal image of the surface region. A data capture device records the thermal image in synchronicity with each pulse of the pulsed signal such that a time series of thermal images is generated. For enhanced sensitivity and/or repeatability, sound and/or vibrations at the surface region can be used in feedback control of the pulsed signal applied to the acoustic sources.

Mitigation of nonpoint source pollution in rural areas: From control to synergies of multi ecosystem services.

PubMed

Wu, Yonghong; Liu, Junzhuo; Shen, Renfang; Fu, Bojie

2017-12-31

Nonpoint source (NPS) pollution produced by human activities in rural areas has induced excessive nutrient input into surface waters and the decline of water quality. The essence of NPS pollution is the transport of nutrients between soil and water. Traditional NPS pollution control strategies, however, are mainly based on the solid and liquid phases, with little focus on the bio-phase between water and soil. The pollutants produced from NPS can be regarded as a resource if recycled or reused in an appropriate way in the agricultural ecosystem. This mini review proposes novel strategies for NPS pollution control based on three phases (liquid, solid and bio-phase) and highlights the regulating services of an agricultural ecosystem by optimizing land use/cover types. Copyright © 2017 Elsevier B.V. All rights reserved.

RACT/BACT/LAER Clearninghouse (RBLC)

EPA Pesticide Factsheets

OAR's RACT, BACT, LAER Clearinghouse (RBLC) data asset contains summary information on selected air permitting actions from EPA, state, and local permitting agencies across the U.S., as well as a number of international permit records supplied by air pollution control agencies in Mexico and Canada. The acronyms refer to program requirements of the New Source Review (NSR) program: RACT is Reasonably Available Control Technology and applies to existing sources in areas that are not meeting national ambient air quality standards (i.e., non-attainment areas); BACT is Best Available Control Technology and applies to major new or modified sources in clean areas (i.e., attainment areas). LAER, or Lowest Achievable Emission Rate, is required on major new or modified sources in non-attainment areas. As of 2012, RBLC includes approximately 6,500 entries. With the exception of LAER permit determinations, whose inclusion in RBLC is mandatory, participation is voluntary. Coverage is therefore not complete or necessarily representative.Required under Section 108 of the 1990 Amendments to the Clean Air Act, RBLC provides users 00e2?? typically permit writers, permit applicants or holders, and the public 00e2?? with references and personal contacts to support ongoing air pollution control activities. Information is detailed enough for users to know whether a permit is applicable to their needs. Users may then contact the appropriate agency to access the permit or discuss it wit

Prepared by: U.S. Environmental Protection Agency Office of Water Regulations and Standards Office of Wetlands Protection June 1990

EPA Pesticide Factsheets

Information and guidance on the coordination of State and Federal Non-Point Source (CWA, Section 319) control and wetland programs (CWA, Section 404)and the implementation of activities that can benefit both programs

Influence of Three Contrasting Detrital Carbon Sources on Planktonic Bacterial Metabolism in a Mesotrophic Lake.

PubMed

Wehr; Petersen; Findlay

1999-01-01

Abstract Lakes receive organic carbon from a diversity of sources which vary in their contribution to planktonic microbial food webs. We conducted a mesocosm study to test the effects of three different detrital carbon sources (algae, aquatic macrophytes, terrestrial leaves) on several measures of microbial metabolism in a small meso-eutrophic lake (DOC approximately 5 mg/L). Small DOC additions (DeltaC < 1 mg/L) affected bacterial numbers, growth, and pathways of carbon acquisition. Macrophyte and leaf detritus significantly increased TDP and color, but bacterial densities initially (+12 h) were unaffected. After 168 h, densities in systems amended with terrestrial detritus were 60% less than in controls, while production rates in mesocosms with macrophyte detritus were 4-fold greater. Detritus treatments resulted in greater per-cell production rates either through stable cell numbers and greater growth rates (macrophyte-C) or lower densities with stable production rates (terrestrial-C). After only 12 h, rates of leucine aminopeptidase (LAPase) activity were 2.5x greater in macrophyte-C systems than in controls, but LAPase and beta-N-acetylglucosamindase activities in systems amended with terrestrial-C were only 50% of rates in controls. After 168 h, beta-xylosidase rates were significantly greater in communities with terrestrial and phytoplankton detritus. Microbial utilization of >20% of 102 carbon sources tested were affected by at least one detritus addition. Macrophyte-C had positive (6% of substrates) and negative (14%) effects on substrate use; terrestrial detritus had mainly positive effects. An ordination based on carbon-use profiles (+12 h) revealed a cluster of macrophyte-amended communities with greater use of psicose, lactulose, and succinamic acid; controls and algal-detritus systems were more effective in metabolizing two common sugars and cellobiose. After 168 h, communities receiving terrestrial detritus were most tightly clustered, exhibiting greater use of raffinose, pyroglutamic acid, and sebacic acid. Results suggest that pelagic bacterial communities respond to changes in organic carbon source rapidly and by different routes, including shifts in per-cell production rates and variations in degradation of a variety of compounds comprising the DOC pool.

Seasonal variation of nitrogen-concentration in the surface water and its relationship with land use in a catchment of northern China.

PubMed

Chen, Li-ding; Peng, Hong-jia; Fu, Bo-Jie; Qiu, Jun; Zhang, Shu-rong

2005-01-01

Surface waters can be contaminated by human activities in two ways: (1) by point sources, such as sewage treatment discharge and storm-water runoff; and (2) by non-point sources, such as runoff from urban and agricultural areas. With point-source pollution effectively controlled, non-point source pollution has become the most important environmental concern in the world. The formation of non-point source pollution is related to both the sources such as soil nutrient, the amount of fertilizer and pesticide applied, the amount of refuse, and the spatial complex combination of land uses within a heterogeneous landscape. Land-use change, dominated by human activities, has a significant impact on water resources and quality. In this study, fifteen surface water monitoring points in the Yuqiao Reservoir Basin, Zunhua, Hebei Province, northern China, were chosen to study the seasonal variation of nitrogen concentration in the surface water. Water samples were collected in low-flow period (June), high-flow period (July) and mean-flow period (October) from 1999 to 2000. The results indicated that the seasonal variation of nitrogen concentration in the surface water among the fifteen monitoring points in the rainfall-rich year is more complex than that in the rainfall-deficit year. It was found that the land use, the characteristics of the surface river system, rainfall, and human activities play an important role in the seasonal variation of N-concentration in surface water.

Parameter Measurement Methods for Interfacing Hydraulic Systems with Microelectronic Instruments and Controllers.

DTIC Science & Technology

1983-11-01

successfully. I- Accession For NTIS -GO iiiONa DTIC TAB t Unannounced - Justificatio Distribution/ I Availability Codes vail and/or DIst Special IA-11...terms of initial signal power. An active sensor must be excited externally. Such a sensor receives its power from an external source and merely modulates...electrons in the material to gain L enough energy to be emitted. The voltage source causes a positive potential to be felt on the collector, thus causing the

Angiotensin-converting enzyme-inhibitory activity in protein hydrolysates from normal and anthracnose disease-damaged Phaseolus vulgaris seeds.

PubMed

Hernández-Álvarez, Alan Javier; Carrasco-Castilla, Janet; Dávila-Ortiz, Gloria; Alaiz, Manuel; Girón-Calle, Julio; Vioque-Peña, Javier; Jacinto-Hernández, Carmen; Jiménez-Martínez, Cristian

2013-03-15

Bean seeds are an inexpensive source of protein. Anthracnose disease caused by the fungus Colletotrichum lindemuthianum results in serious losses in common bean (Phaseolus vulgaris L.) crops worldwide, affecting any above-ground plant part, and protein dysfunction, inducing the synthesis of proteins that allow plants to improve their stress tolerance. The aim of this study was to evaluate the use of beans damaged by anthracnose disease as a source of peptides with angiotensin-converting enzyme (ACE-I)-inhibitory activity. Protein concentrates from beans spoiled by anthracnose disease and from regular beans as controls were prepared by alkaline extraction and precipitation at isolelectric pH and hydrolysed using Alcalase 2.4 L. The hydrolysates from spoiled beans had ACE-I-inhibitory activity (IC(50) 0.0191 mg protein mL(-1)) and were very similar to those from control beans in terms of ACE-I inhibition, peptide electrophoretic profile and kinetics of hydrolysis. Thus preparation of hydrolysates using beans affected by anthracnose disease would allow for revalorisation of this otherwise wasted product. The present results suggest the use of spoiled bean seeds, e.g. anthracnose-damaged beans, as an alternative for the isolation of ACE-I-inhibitory peptides to be further introduced as active ingredients in functional foods. © 2012 Society of Chemical Industry.

A novel control process of cyanobacterial bloom using cyanobacteriolytic bacteria immobilized in floating biodegradable plastic carriers.

PubMed

Nakamura, N; Nakano, K; Sugiura, N; Matsumura, M

2003-12-01

A process using a floating carrier for immobilization of cyanobacteriolytic bacteria, B.cereus N-14, was proposed to realize an effective in situ control of natural floating cyanobacterial blooms. The critical concentrations of the cyanobacteriolytic substance and B.cereus N-14 cells required to exhibit cyanobacteriolytic activity were investigated. The results indicated the necessity of cell growth to produce sufficiently high amounts of the cyanobacteriolytic substance to exhibit its activity and also for conditions enabling good contact between high concentrations of the cyanobacteriolytic substance and cyanobacteria. Floating biodegradable plastics made of starch were applied as a carrier material to maintain close contact between the immobilized cyanobacteriolytic bacteria and floating cyanobacteria. The floating starch-carriers could eliminate 99% of floating cyanobacteria in 4 d. Since B.cereus N-14 could produce the cyanobacteriolytic substance under the presence of starch and some amino acids, the cyanobacteriolytic activity could be attributed to carbon source fed from starch carrier and amino acids eluted from lysed cyanobacteria. Therefore, the effect of using a floating starch-carrier was confirmed from both view points as a carrier for immobilization and a nutrient source to stimulate cyanobacteriolytic activity. The new concept to apply a floating carrier immobilizing useful microorganisms for intensive treatment of a nuisance floating target was demonstrated.

Regional-scale controls on the spatial activity of rockfalls (Turtmann Valley, Swiss Alps) - A multivariate modeling approach

NASA Astrophysics Data System (ADS)

Messenzehl, Karoline; Meyer, Hanna; Otto, Jan-Christoph; Hoffmann, Thomas; Dikau, Richard

2017-06-01

In mountain geosystems, rockfalls are among the most effective sediment transfer processes, reflected in the regional-scale distribution of talus slopes. However, the understanding of the key controlling factors seems to decrease with increasing spatial scale, due to emergent and complex system behavior and not least to recent methodological shortcomings in rockfall modeling research. In this study, we aim (i) to develop a new approach to identify major regional-scale rockfall controls and (ii) to quantify the relative importance of these controls. Using a talus slope inventory in the Turtmann Valley (Swiss Alps), we applied for the first time the decision-tree based random forest algorithm (RF) in combination with a principal component logistic regression (PCLR) to evaluate the spatial distribution of rockfall activity. This study presents new insights into the discussion on whether periglacial rockfall events are controlled more by topo-climatic, cryospheric, paraglacial or/and rock mechanical properties. Both models explain the spatial rockfall pattern very well, given the high areas under the Receiver Operating Characteristic (ROC) curves of > 0.83. Highest accuracy was obtained by the RF, correctly predicting 88% of the rockfall source areas. The RF appears to have a great potential in geomorphic research involving multicollinear data. The regional permafrost distribution, coupled to the bedrock curvature and valley topography, was detected to be the primary rockfall control. Rockfall source areas cluster within a low-radiation elevation belt (2900-3300 m a.s.l,) consistent with a permafrost probability of > 90%. The second most important factor is the time since deglaciation, reflected by the high abundance of rockfalls along recently deglaciated (< 100 years), north-facing slopes. However, our findings also indicate a strong rock mechanical control on the paraglacial rockfall activity, declining either exponentially or linearly since deglaciation. The study demonstrates the benefit of combined statistical approaches for predicting rockfall activity in deglaciated, permafrost-affected mountain valleys and highlights the complex interplay between rock mechanical, paraglacial and topo-climatic controls at the regional scale.

A Radiation Laboratory Curriculum Development at Western Kentucky University

NASA Astrophysics Data System (ADS)

Barzilov, Alexander P.; Novikov, Ivan S.; Womble, Phil C.

2009-03-01

We present the latest developments for the radiation laboratory curriculum at the Department of Physics and Astronomy of Western Kentucky University. During the last decade, the Applied Physics Institute (API) at WKU accumulated various equipment for radiation experimentation. This includes various neutron sources (computer controlled d-t and d-d neutron generators, and isotopic 252 Cf and PuBe sources), the set of gamma sources with various intensities, gamma detectors with various energy resolutions (NaI, BGO, GSO, LaBr and HPGe) and the 2.5-MeV Van de Graaff particle accelerator. XRF and XRD apparatuses are also available for students and members at the API. This equipment is currently used in numerous scientific and teaching activities. Members of the API also developed a set of laboratory activities for undergraduate students taking classes from the physics curriculum (Nuclear Physics, Atomic Physics, and Radiation Biophysics). Our goal is to develop a set of radiation laboratories, which will strengthen the curriculum of physics, chemistry, geology, biology, and environmental science at WKU. The teaching and research activities are integrated into real-world projects and hands-on activities to engage students. The proposed experiments and their relevance to the modern status of physical science are discussed.

Topographic analysis of individual activation patterns in medial frontal cortex in schizophrenia

PubMed Central

Stern, Emily R.; Welsh, Robert C.; Fitzgerald, Kate D.; Taylor, Stephan F.

2009-01-01

Individual variability in the location of neural activations poses a unique problem for neuroimaging studies employing group averaging techniques to investigate the neural bases of cognitive and emotional functions. This may be especially challenging for studies examining patient groups, which often have limited sample sizes and increased intersubject variability. In particular, medial frontal cortex (MFC) dysfunction is thought to underlie performance monitoring dysfunction among patients with previous studies using group averaging to have yielded conflicting results. schizophrenia, yet compare schizophrenic patients to controls To examine individual activations in MFC associated with two aspects of performance monitoring, interference and error processing, functional magnetic resonance imaging (fMRI) data were acquired while 17 patients with schizophrenia and 21 healthy controls performed an event-related version of the multi-source interference task. Comparisons of averaged data revealed few differences between the groups. By contrast, topographic analysis of individual activations for errors showed that control subjects exhibited activations spanning across both posterior and anterior regions of MFC while patients primarily activated posterior MFC, possibly reflecting an impaired emotional response to errors in schizophrenia. This discrepancy between topographic and group-averaged results may be due to the significant dispersion among individual activations, particularly among healthy controls, highlighting the importance of considering intersubject variability when interpreting the medial frontal response to error commission. PMID:18819107

Environmental effects of energy production and utilization in the U. S. Volume I. Sources, trends, and costs of control

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

Newkirk, H.W.

1976-05-01

Volume I deals with sources (what the emissions are and where they come from), trends (quantities of emissions and their dispersion with time), and costs of control (what it takes in time, energy, and money to meet minimum standards). Volume II concerns itself with the public health effects of energy production and utilization. Volume III summarizes the various techniques for controlling emissions, technological as well as economic, social, and political. (For abstracts of Vols. II and III, see ERDA Energy Research Abstracts, Vol. 2, Absts. 5764 and 5670, respectively) Each volume is divided into sections dealing with the atmosphere, water,more » land, and social activities--each division indicating a particular sphere of man's environment affected by energy production and use. The sources of information that were used in this study included textbooks, journal articles, technical reports, memoranda, letters, and personal communications. These are cited in the text at the end of each subsection and on the applicable tables and figures.« less

Preliminary phytochemical screening and in vitro anti-Helicobacter pylori activity of acetone and aqueous extracts of the stem bark of Sclerocarya birrea (Anacardiaceae).

PubMed

Njume, Collise; Afolayan, Anthony J; Ndip, Roland N

2011-04-01

Helicobacter pylori antibiotic resistance and other problems associated with combination therapy have generated a considerable interest in the search for alternative therapeutic agents. In order to identify novel sources of such agents, the antimicrobial activity of five solvent extracts of the stem bark of Sclerocarya birrea was investigated against 30 clinical strains of H. pylori and a reference strain NCTC 11638 using standard microbiological techniques. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. The active phytocomponents were detected by TLC and indirect bioautography. All the extracts exhibited anti-H. pylori activity with zone diameters of inhibition between 0 and 21 mm. The acetone and aqueous extracts showed potent anti-H. pylori activity with minimum inhibitory concentration (MIC(90)) values ranging from 0.06-2.50 mg/mL, whereas those for the control antibiotics ranged from 0.001-5.0 mg/mL. The acetone extract was highly bactericidal at 1.2 mg/mL with complete elimination of the organisms within 18 h. The activity of both acetone and aqueous extracts was better than metronidazole (p<0.05). Most of the active phytocomponents were located in the acetone extract; R(f)≤0.62 with >90% inhibition. These results demonstrate that the acetone and aqueous extracts of S. birrea may contain compounds with therapeutic activity; therefore, they may represent potential sources of new anti-H. pylori regimen. Copyright © 2011 IMSS. Published by Elsevier Inc. All rights reserved.

Active noise control: A tutorial for HVAC designers

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

Gelin, L.J.

1997-08-01

This article will identify the capabilities and limitations of ANC in its application to HVAC noise control. ANC can be used in ducted HVAC systems to cancel ductborne, low-frequency fan noise by injecting sound waves of equal amplitude and opposite phase into an air duct, as close as possible to the source of the unwanted noise. Destructive interference of the fan noise and injected noise results in sound cancellation. The noise problems that it solves are typically described as rumble, roar or throb, all of which are difficult to address using traditional noise control methods. This article will also contrastmore » the use of active against passive noise control techniques. The main differences between the two noise control measures are acoustic performance, energy consumption, and design flexibility. The article will first present the fundamentals and basic physics of ANC. The application to real HVAC systems will follow.« less

Controls on water vapor isotopes over Roorkee, India: Impact of convective activities and depression systems

NASA Astrophysics Data System (ADS)

Saranya, P.; Krishan, Gopal; Rao, M. S.; Kumar, Sudhir; Kumar, Bhishm

2018-02-01

The study evaluates the water vapor isotopic compositions and its controls with special reference to Indian Summer Monsoon (ISM) season at Roorkee, India. Precipitation is usually a discrete event spatially and temporally in this part of the country, therefore, the information provided is limited, while, the vapors have all time availability and have a significant contribution in the hydrological cycle locally or over a regional scale. Hence for understanding the processes altering the various sources, its isotopic signatures were studied. The Isotope Water Vapour Line (Iso Val) was drawn together with the Global Meteoric Water Line (GMWL) and the best fit line was δD = 5.42 * δ18O + 27.86. The precipitation samples were also collected during the study period and were best fitted with δD = 8.20(±0.18) * δ18O + 9.04(±1.16) in the Local Meteoric Water Line (LMWL). From the back trajectory analysis of respective vapor samples, it is unambiguous that three major sources viz; local vapor, western disturbance and monsoon vapor are controlling the fate of moisture over Roorkee. The d-excess in ground-level vapor (GLV) reveals the supply of recycled moisture from continental water bodies and evapo-transpiration as additional moisture sources to the study area. The intensive depletion in isotopic ratios was associated with the large-scale convective activity and low-pressure/cyclonic/depression systems formed over Bay of Bengal.

Antioxidation status and histidine dipeptides content in broiler blood and muscles depending on protein sources in feed.

PubMed

Kopeć, W; Jamroz, D; Wiliczkiewicz, A; Biazik, E; Hikawczuk, T; Skiba, T; Pudło, A; Orda, J

2013-06-01

One-day-old chickens were fed mixtures containing different raw materials (fish by-products meal, porcine blood cells meal, blood meal, wheat gluten, fodder yeast), as a source of histidine and β-alanine - components of carnosine. Control birds were administered a feed mixture, in which soy bean meal was the main protein source. The bodyweight, feed consumption and conversion, antioxidant characteristics and histidine dipeptides content in blood and muscles, and also amino acid composition of chicken meat on day 34 post-hatch were recorded. The best (p < 0.05) performance and feed conversion were observed in chickens fed mixture containing porcine blood cells meal. In blood plasma of control chickens, a significantly (p < 0.01) higher ability to scavenge DPPH radicals was found. However, the highest catalase activity in erythrocytes was determined in chickens fed mixtures with blood by-products. Insignificant differences in both carnosine and anserine levels in plasma between treatments were noted. Breast muscles from control birds were characterized by lower activity of glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) (p < 0.05; p < 0.01), than those from chickens fed blood by-products. Improved ability to reduce ferric ions (FRAP) (p < 0.01) and carnosine content in meat from chickens fed blood cell meal were recorded. No direct relations between amino acids content in feed mixtures and in meat were observed. © 2012 Blackwell Verlag GmbH.

EXAMINING THE ROLE AND RESEARCH CHALLENGES OF SOCIAL MEDIA AS A TOOL FOR NONPROLIFERATION AND ARMS CONTROL TREATY VERIFICATION

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

Henry, Michael J.; Cramer, Nicholas O.; Benz, Jacob M.

Traditional arms control treaty verification activities typically involve a combination of technical measurements via physical and chemical sensors, state declarations, political agreements, and on-site inspections involving international subject matter experts. However, the ubiquity of the internet, and the electronic sharing of data that it enables, has made available a wealth of open source information with the potential to benefit verification efforts. Open source information is already being used by organizations such as the International Atomic Energy Agency to support the verification of state-declared information, prepare inspectors for in-field activities, and to maintain situational awareness . The recent explosion in socialmore » media use has opened new doors to exploring the attitudes, moods, and activities around a given topic. Social media platforms, such as Twitter, Facebook, and YouTube, offer an opportunity for individuals, as well as institutions, to participate in a global conversation at minimal cost. Social media data can also provide a more data-rich environment, with text data being augmented with images, videos, and location data. The research described in this paper investigates the utility of applying social media signatures as potential arms control and nonproliferation treaty verification tools and technologies, as determined through a series of case studies. The treaty relevant events that these case studies touch upon include detection of undeclared facilities or activities, determination of unknown events recorded by the International Monitoring System (IMS), and the global media response to the occurrence of an Indian missile launch. The case studies examine how social media can be used to fill an information gap and provide additional confidence to a verification activity. The case studies represent, either directly or through a proxy, instances where social media information may be available that could potentially augment the evaluation of an event. The goal of this paper is to instigate a discussion within the verification community as to where and how social media can be effectively utilized to complement and enhance traditional treaty verification efforts. In addition, this paper seeks to identify areas of future research and development necessary to adapt social media analytic tools and techniques, and to form the seed for social media analytics to aid and inform arms control and nonproliferation policymakers and analysts. While social media analysis (as well as open source analysis as a whole) will not ever be able to replace traditional arms control verification measures, they do supply unique signatures that can augment existing analysis.« less

Disruption of melatonin synthesis is associated with impaired 14-3-3 and miR-451 levels in patients with autism spectrum disorders.

PubMed

Pagan, Cécile; Goubran-Botros, Hany; Delorme, Richard; Benabou, Marion; Lemière, Nathalie; Murray, Kerren; Amsellem, Frédérique; Callebert, Jacques; Chaste, Pauline; Jamain, Stéphane; Fauchereau, Fabien; Huguet, Guillaume; Maronde, Erik; Leboyer, Marion; Launay, Jean-Marie; Bourgeron, Thomas

2017-05-18

Autism spectrum disorders (ASD) are characterized by a wide genetic and clinical heterogeneity. However, some biochemical impairments, including decreased melatonin (crucial for circadian regulation) and elevated platelet N-acetylserotonin (the precursor of melatonin) have been reported as very frequent features in individuals with ASD. To address the mechanisms of these dysfunctions, we investigated melatonin synthesis in post-mortem pineal glands - the main source of melatonin (9 patients and 22 controls) - and gut samples - the main source of serotonin (11 patients and 13 controls), and in blood platelets from 239 individuals with ASD, their first-degree relatives and 278 controls. Our results elucidate the enzymatic mechanism for melatonin deficit in ASD, involving a reduction of both enzyme activities contributing to melatonin synthesis (AANAT and ASMT), observed in the pineal gland as well as in gut and platelets of patients. Further investigations suggest new, post-translational (reduced levels of 14-3-3 proteins which regulate AANAT and ASMT activities) and post-transcriptional (increased levels of miR-451, targeting 14-3-3ζ) mechanisms to these impairments. This study thus gives insights into the pathophysiological pathways involved in ASD.

100 s extraction of negative ion beams by using actively temperature-controlled plasma grid

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

Kojima, A., E-mail: kojima.atsushi@jaea.go.jp; Hanada, M.; Yoshida, M.

2014-02-15

Long pulse beam extraction with a current density of 120 A/m{sup 2} for 100 s has been achieved with a newly developed plasma grid (PG) for the JT-60SA negative ion source which is designed to produce high power and long pulse beams with a negative ion current of 130 A/m{sup 2} (22 A) and a pulse length of 100 s. The PG temperature is regulated by fluorinated fluids in order to keep the high PG temperature for the cesium-seeded negative ion production. The time constant for temperature controllability of the PG was measured to be below 10 s, which wasmore » mainly determined by the heat transfer coefficient of the fluorinated fluid. The measured decay time of the negative ion current extracted from the actively temperature-controlled PG was 430 s which was sufficient for the JT-60SA requirement, and much longer than that by inertial-cooling PG of 60 s. Obtained results of the long pulse capability are utilized to design the full size PG for the JT-60SA negative ion source.« less

[Neurofeedback for the treatment of chronic tinnitus : Review and future perspectives].

PubMed

Kleinjung, T; Thüring, C; Güntensperger, D; Neff, P; Meyer, M

2018-03-01

Neurofeedback is a noninvasive neuromodulation technique employing real-time display of brain activity in terms of electroencephalography (EEG) signals to teach self-regulation of distinct patterns of brain activity or influence brain activity in a targeted manner. The benefit of this approach for control of symptoms in attention deficit disorders, hyperactivity, depression, and migraine has been proven. Studies in recent years have also repeatedly shown this treatment to improve tinnitus symptoms, although it has not become established as routine therapy. The primary focus of this review is the rational of EEG neurofeedback for tinnitus treatment and the currently available data from published studies. Furthermore, alternative neurofeedback protocols using real-time functional magnetic resonance imaging (fMRI) measurements for tinnitus control are considered. Finally, this article highlights how modern EEG analysis (source localization, connectivity) and the improving understanding of tinnitus pathology can contribute to development of more focused neurofeedback protocols for more sustainable control of tinnitus.

Atmospheric effects on active illumination

NASA Astrophysics Data System (ADS)

Shaw, Scot E. J.; Kansky, Jan E.

2005-08-01

For some beam-control applications, we can rely on the cooperation of the target when gathering information about the target location and the state of the atmosphere between the target and the beam-control system. The typical example is a cooperative point-source beacon on the target. Light from such a beacon allows the beam-control system to track the target accurately, and, if higher-order adaptive optics is to be employed, to make wave-front measurements and apply appropriate corrections with a deformable mirror. In many applications, including directed-energy weapons, the target is not cooperative. In the absence of a cooperative beacon, we must find other ways to collect the relevant information. This can be accomplished with an active-illumination system. Typically, this means shining one or more lasers at the target and observing the reflected light. In this paper, we qualitatively explore a number of difficulties inherent to active illumination, and suggest some possible mitigation techniques.

Magnetoencephalography of frontotemporal dementia: spatiotemporally localized changes during semantic decisions

PubMed Central

Nestor, Peter J.; Hodges, John R.; Rowe, James B.

2011-01-01

Behavioural variant frontotemporal dementia is a neurodegenerative disorder with dysfunction and atrophy of the frontal lobes leading to changes in personality, behaviour, empathy, social conduct and insight, with relative preservation of language and memory. As novel treatments begin to emerge, biomarkers of frontotemporal dementia will become increasingly important, including functionally relevant neuroimaging indices of the neurophysiological basis of cognition. We used magnetoencephalography to examine behavioural variant frontotemporal dementia using a semantic decision task that elicits both frontal and temporal activity in healthy people. Twelve patients with behavioural variant frontotemporal dementia (age 50–75) and 16 matched controls made categorical semantic judgements about 400 pictures during continuous magnetoencephalography. Distributed source analysis was used to compare patients and controls. The patients had normal early responses to picture confrontation, indicating intact visual processing. However, a predominantly posterior set of regions including temporoparietal cortex showed reduced source activity 250–310 ms after stimulus onset, in proportion to behavioural measures of semantic association. In contrast, a left frontoparietal network showed reduced source activity at 550–650 ms, proportional to patients’ deficits in attention and orientation. This late deficit probably reflects impairment in the neural substrate of goal-oriented decision making. The results demonstrate behaviourally relevant neural correlates of semantic processing and decision making in behavioural variant frontotemporal dementia, and show for the first time that magnetoencephalography can be used to study cognitive systems in the context of frontotemporal dementia. PMID:21840892

Cost effectiveness of recombinant activated factor VII for the control of bleeding in patients with severe blunt trauma injuries in the United Kingdom.

PubMed

Morris, S; Ridley, S; Munro, V; Christensen, M C

2007-01-01

The aim of this study was to assess the lifetime cost effectiveness of recombinant activated factor VII vs placebo as adjunctive therapy for control of bleeding in patients with severe blunt trauma in the UK. We developed a cost-effectiveness model based on patient level data from a 30-day international, randomised, placebo-controlled Phase II trial. The data were supplemented with secondary data from UK sources to estimate lifetime costs and benefits. The model produced a baseline estimate of the incremental cost per life year gained with recombinant activated factor VII relative to placebo of 12 613 UK pounds. The incremental cost per quality adjusted life year gained was 18 825 UK pounds. These estimates are sensitive to the choice of discount rate and health state utility values used. Preliminary results suggest that relative to placebo, recombinant activated factor VII may be a cost-effective therapy to the UK National Health Service.

76 FR 5212 - Employment and Training Administration

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-28

... Collection for Internal Fraud and Overpayment Detection and Recovery Activities (OMB Control No. 1205-0187... of data on a revised form ETA 9000 that provides information about Internal Fraud and Overpayment...: I. Background The ETA 9000 is the only data source available on: (1) Instances of internal fraud...

Bibliography of Water Quality Research Reports.

ERIC Educational Resources Information Center

Environmental Protection Agency, Washington, DC. Office of Research and Development.

Prepared for the Environmental Protection Agency (EPA), this bibliography of published reports covers information concerning the advancement of water pollution control technology and knowledge. The reports provide a central source of information on the research, development, and demonstration activities in the water research program of the EPA,…

PHARMACEUTICALS AND PERSONAL CARE PRODUCTS IN THE ENVIRONMENT: OVERARCHING ISSUES AND OVERVIEW

EPA Science Inventory

While the point-source emissions of pollutants from manufacturing waste streams have long been monitored and subject to controls, the environmental impact of the public's (i.e., the individual's) activities regarding the use of chemicals is more difficult to assess. Of particula...

Neutral particle beam intensity controller

DOEpatents

Dagenhart, William K.

1986-01-01

A neutral beam intensity controller is provided for a neutral beam generator in which a neutral beam is established by accelerating ions from an ion source into a gas neutralizer. An amplitude modulated, rotating magnetic field is applied to the accelerated ion beam in the gas neutralizer to defocus the resultant neutral beam in a controlled manner to achieve intensity control of the neutral beam along the beam axis at constant beam energy. The rotating magnetic field alters the orbits of ions in the gas neutralizer before they are neutralized, thereby controlling the fraction of neutral particles transmitted out of the neutralizer along the central beam axis to a fusion device or the like. The altered path or defocused neutral particles are sprayed onto an actively cooled beam dump disposed perpendicular to the neutral beam axis and having a central open for passage of the focused beam at the central axis of the beamline. Virtually zero therough 100% intensity control is achieved by varying the magnetic field strength without altering the ion source beam intensity or its species yield.

A Look at the Future of Controlled-Source Seismology

NASA Astrophysics Data System (ADS)

Keller, G. R.; Klemperer, S.; Hole, J.; Snelson, C.

2008-12-01

Facilities like EarthScope and IRIS/PASSCAL offer a framework in which to re-assess the role of our highest- resolution geophysical tool, controlled-source seismology. This tool is effective in near surface studies that focus on the upper 100 m of the crust to studies that focus on Moho structure and the lithospheric mantle. IRIS has now existed for over two decades and has transformed the way in which passive-source seismology in particular is carried out. Progress over these two decades has led to major discoveries about continental architecture and evolution through the development of three-dimensional images of the upper mantle and lithosphere. Simultaneously the hydrocarbon exploration industry has mapped increasingly large fractions of our sedimentary basins in three-dimensions and at unprecedented resolution and fidelity. Thanks to the additional instruments in the EarthScope facility, a clear scientific need and opportunity exists to map, at similar resolution, all of the crust - the igneous/metamorphic basement, the non-petroliferous basins that contain the record of continental evolution, and the seismogenic faults and active volcanoes that are the principal natural hazards we face. Controlled-source seismology remains the fundamental technology behind exploration for all fossil fuels and many water resources, and as such is a multi-billion-dollar industry centered in the USA. Academic scientists are leaders in developing the algorithms to process the most advanced industry data, but lack the academic data sets to which to apply this technology. University and government controlled-source seismologists, and their students who will populate the exploration industry, are increasingly divorced from that industry by their reliance on sparse spatial recording of usually only a single-component of the wavefield, generated by even sparser seismic sources. However, if we can find the resources, the technology now exists to provide seismic images of immense scientific and societal value that play a key role in fulfilling the ambitious missions of EarthScope and other NSF programs, as well as, those of agencies such as the U. S. Geological Survey and Department of Energy. US controlled-source community has self-organized to form an IASPEI U.S. National Committee on Controlled-Source Seismology to facilitate communication and to present and pursue the fundamental needs to sustain this scientific community as a resource for all earth scientists.

Designing and testing a classroom curriculum to teach preschoolers about the biology of physical activity: The respiration system as an underlying biological causal mechanism

NASA Astrophysics Data System (ADS)

Ewing, Tracy S.

The present study examined young children's understanding of respiration and oxygen as a source of vital energy underlying physical activity. Specifically, the purpose of the study was to explore whether a coherent biological theory, characterized by an understanding that bodily parts (heart and lungs) and processes (oxygen in respiration) as part of a biological system, can be taught as a foundational concept to reason about physical activity. The effects of a biology-based intervention curriculum designed to teach preschool children about bodily functions as a part of the respiratory system, the role of oxygen as a vital substance and how physical activity acts an energy source were examined. Participants were recruited from three private preschool classrooms (two treatment; 1 control) in Southern California and included a total of 48 four-year-old children (30 treatment; 18 control). Findings from this study suggested that young children could be taught relevant biological concepts about the role of oxygen in respiratory processes. Children who received biology-based intervention curriculum made significant gains in their understanding of the biology of respiration, identification of physical and sedentary activities. In addition these children demonstrated that coherence of conceptual knowledge was correlated with improved accuracy at activity identification and reasoning about the inner workings of the body contributing to endurance. Findings from this study provided evidence to support the benefits of providing age appropriate but complex coherent biological instruction to children in early childhood settings.

Impact of red versus blue light on tolerability and efficacy of PDT: a randomized controlled trial.

PubMed

Gholam, Patrick; Bosselmann, Ina; Enk, Alexander; Fink, Christine

2018-06-01

Various light sources may be used for photodynamic therapy of actinic keratosis since photosensitizing agents are activated by different wavelengths. However, the relative impact of red and blue light irradiation on the efficacy and tolerability of therapy is controversial. The aim of this study is to compare the efficacy and tolerability of therapy with red versus blue light sources, as well as the patients' evaluation of cosmetic results, clinical response, painfulness and preferred light source for future photodynamic treatments. This is a prospective, single-center, randomized, controlled, open-label study with 28 patients undergoing elective photodynamic therapy. Red and blue light sources both showed very good results with a complete response rate of 84 % and 85 % respectively. Pain during photodynamic therapy was 6.1 vs. 5.4 (and 2.1 vs. 1.5 eight hours after therapy) on the visual analogue scale. Although these differences were statistically significant, the clinical relevance is low, since the number of therapy interruptions were equally distributed in both groups, and patients' subjective evaluation of the treatment showed no personal preference towards the light sources. Both light sources showed very good clinical results and satisfactory tolerability in this study. © 2018 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Constitutively active 5-HT2/α1 receptors facilitate muscle spasms after human spinal cord injury

PubMed Central

D'Amico, Jessica M.; Murray, Katherine C.; Li, Yaqing; Chan, K. Ming; Finlay, Mark G.; Bennett, David J.

2013-01-01

In animals, the recovery of motoneuron excitability in the months following a complete spinal cord injury is mediated, in part, by increases in constitutive serotonin (5-HT2) and norepinephrine (α1) receptor activity, which facilitates the reactivation of calcium-mediated persistent inward currents (CaPICs) without the ligands serotonin and norepinephrine below the injury. In this study we sought evidence for a similar role of constitutive monoamine receptor activity in the development of spasticity in human spinal cord injury. In chronically injured participants with partially preserved sensory and motor function, the serotonin reuptake inhibitor citalopram facilitated long-lasting reflex responses (spasms) previously shown to be mediated by CaPICs, suggesting that in incomplete spinal cord injury, functional descending sources of monoamines are present to activate monoamine receptors below the lesion. However, in participants with motor or motor/sensory complete injuries, the inverse agonist cyproheptadine, which blocks both ligand and constitutive 5-HT2/α1 receptor activity, decreased long-lasting reflexes, whereas the neutral antagonist chlorpromazine, which only blocks ligand activation of these receptors, had no effect. When tested in noninjured control participants having functional descending sources of monoamines, chlorpromazine was effective in reducing CaPIC-mediated motor unit activity. On the basis of these combined results, it appears that in severe spinal cord injury, facilitation of persistent inward currents and muscle spasms is mainly mediated by the activation of constitutive 5-HT2 and α1 receptor activity. Drugs that more selectively block these constitutively active monoamine receptors may provide better oral control of spasticity, especially in motor complete spinal cord injury where reducing motoneuron excitability is the primary goal. PMID:23221402

Noise levels from a model turbofan engine with simulated noise control measures applied

NASA Technical Reports Server (NTRS)

Hall, David G.; Woodward, Richard P.

1993-01-01

A study of estimated full-scale noise levels based on measured levels from the Advanced Ducted Propeller (ADP) sub-scale model is presented. Testing of this model was performed in the NASA Lewis Low Speed Anechoic Wind Tunnel at a simulated takeoff condition of Mach 0.2. Effective Perceived Noise Level (EPNL) estimates for the baseline configuration are documented, and also used as the control case in a study of the potential benefits of two categories of noise control. The effect of active noise control is evaluated by artificially removing various rotor-stator interaction tones. Passive noise control is simulated by applying a notch filter to the wind tunnel data. Cases with both techniques are included to evaluate hybrid active-passive noise control. The results for EPNL values are approximate because the original source data was limited in bandwidth and in sideline angular coverage. The main emphasis is on comparisons between the baseline and configurations with simulated noise control measures.

Development of multi-pixel x-ray source using oxide-coated cathodes.

PubMed

Kandlakunta, Praneeth; Pham, Richard; Khan, Rao; Zhang, Tiezhi

2017-07-07

Multiple pixel x-ray sources facilitate new designs of imaging modalities that may result in faster imaging speed, improved image quality, and more compact geometry. We are developing a high-brightness multiple-pixel thermionic emission x-ray (MPTEX) source based on oxide-coated cathodes. Oxide cathodes have high emission efficiency and, thereby, produce high emission current density at low temperature when compared to traditional tungsten filaments. Indirectly heated micro-rectangular oxide cathodes were developed using carbonates, which were converted to semiconductor oxides of barium, strontium, and calcium after activation. Each cathode produces a focal spot on an elongated fixed anode. The x-ray beam ON and OFF control is performed by source-switching electronics, which supplies bias voltage to the cathode emitters. In this paper, we report the initial performance of the oxide-coated cathodes and the MPTEX source.

Out of focus - brain attention control deficits in adult ADHD.

PubMed

Salmi, Juha; Salmela, Viljami; Salo, Emma; Mikkola, Katri; Leppämäki, Sami; Tani, Pekka; Hokkanen, Laura; Laasonen, Marja; Numminen, Jussi; Alho, Kimmo

2018-04-24

Modern environments are full of information, and place high demands on the attention control mechanisms that allow the selection of information from one (focused attention) or multiple (divided attention) sources, react to changes in a given situation (stimulus-driven attention), and allocate effort according to demands (task-positive and task-negative activity). We aimed to reveal how attention deficit hyperactivity disorder (ADHD) affects the brain functions associated with these attention control processes in constantly demanding tasks. Sixteen adults with ADHD and 17 controls performed adaptive visual and auditory discrimination tasks during functional magnetic resonance imaging (fMRI). Overlapping brain activity in frontoparietal saliency and default-mode networks, as well as in the somato-motor, cerebellar, and striatal areas were observed in all participants. In the ADHD participants, we observed exclusive activity enhancement in the brain areas typically considered to be primarily involved in other attention control functions: During auditory-focused attention, we observed higher activation in the sensory cortical areas of irrelevant modality and the default-mode network (DMN). DMN activity also increased during divided attention in the ADHD group, in turn decreasing during a simple button-press task. Adding irrelevant stimulation resulted in enhanced activity in the salience network. Finally, the irrelevant distractors that capture attention in a stimulus-driven manner activated dorsal attention networks and the cerebellum. Our findings suggest that attention control deficits involve the activation of irrelevant sensory modality, problems in regulating the level of attention on demand, and may encumber top-down processing in cases of irrelevant information. Copyright © 2018. Published by Elsevier B.V.

Nowcasting influenza outbreaks using open-source media report.

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

Ray, Jaideep; Brownstein, John S.

We construct and verify a statistical method to nowcast influenza activity from a time-series of the frequency of reports concerning influenza related topics. Such reports are published electronically by both public health organizations as well as newspapers/media sources, and thus can be harvested easily via web crawlers. Since media reports are timely, whereas reports from public health organization are delayed by at least two weeks, using timely, open-source data to compensate for the lag in %E2%80%9Cofficial%E2%80%9D reports can be useful. We use morbidity data from networks of sentinel physicians (both the Center of Disease Control's ILINet and France's Sentinelles network)more » as the gold standard of influenza-like illness (ILI) activity. The time-series of media reports is obtained from HealthMap (http://healthmap.org). We find that the time-series of media reports shows some correlation ( 0.5) with ILI activity; further, this can be leveraged into an autoregressive moving average model with exogenous inputs (ARMAX model) to nowcast ILI activity. We find that the ARMAX models have more predictive skill compared to autoregressive (AR) models fitted to ILI data i.e., it is possible to exploit the information content in the open-source data. We also find that when the open-source data are non-informative, the ARMAX models reproduce the performance of AR models. The statistical models are tested on data from the 2009 swine-flu outbreak as well as the mild 2011-2012 influenza season in the U.S.A.« less

Oxidative potential of ambient PM2.5 in the coastal cities of the Bohai Sea, northern China: Seasonal variation and source apportionment.

PubMed

Liu, WeiJian; Xu, YunSong; Liu, WenXin; Liu, QingYang; Yu, ShuangYu; Liu, Yang; Wang, Xin; Tao, Shu

2018-05-01

Emissions of air pollutants from primary and secondary sources in China are considerably higher than those in developed countries, and exposure to air pollution is main risk of public health. Identifying specific particulate matter (PM) compositions and sources are essential for policy makers to propose effective control measures for pollutant emissions. Ambient PM 2.5 samples covered a whole year were collected from three coastal cities of the Bohai Sea. Oxidative potential (OP) was selected as the indicator to characterize associated PM compositions and sources most responsible for adverse impacts on human health. Positive matrix factorization (PMF) and multiple linear regression (MLR) were employed to estimate correlations of PM 2.5 sources with OP. The volume- and mass-based dithiothreitol (DTT v and DTT m ) activities of PM 2.5 were significantly higher in local winter or autumn (p < 0.01). Spatial and seasonal variations in DTT v and DTT m were much larger than mass concentrations of PM 2.5 , indicated specific chemical components are responsible for PM 2.5 derived OP. Strong correlations (r > 0.700, p < 0.01) were found between DTT activity and water-soluble organic carbon (WSOC) and some transition metals. Using PMF, source fractions of PM 2.5 were resolved as secondary source, traffic source, biomass burning, sea spray and urban dust, industry, coal combustion, and mineral dust. Further quantified by MLR, coal combustion, biomass burning, secondary sources, industry, and traffic source were dominant contributors to the water-soluble DTT v activity. Our results also suggested large differences in seasonal contributions of different sources to DTT v variability. A higher contribution of DTT v was derived from coal combustion during the local heating period. Secondary sources exhibited a greater fraction of DTT v in summer, when there was stronger solar radiation. Traffic sources exhibited a prevailing contribution in summer, and industry contributed larger proportions in spring and winter. Future abatement priority of air pollution should reduce the sources contributing to OP of PM 2.5 . Copyright © 2018 Elsevier Ltd. All rights reserved.

Application of a combined approach including contamination indexes, geographic information system and multivariate statistical models in levels, distribution and sources study of metals in soils in Northern China

PubMed Central

Huang, Kuixian; Luo, Xingzhang

2018-01-01

The purpose of this study is to recognize the contamination characteristics of trace metals in soils and apportion their potential sources in Northern China to provide a scientific basis for basic of soil environment management and pollution control. The data set of metals for 12 elements in surface soil samples was collected. The enrichment factor and geoaccumulation index were used to identify the general geochemical characteristics of trace metals in soils. The UNMIX and positive matrix factorizations (PMF) models were comparatively applied to apportion their potential sources. Furthermore, geostatistical tools were used to study the spatial distribution of pollution characteristics and to identify the affected regions of sources that were derived from apportionment models. The soils were contaminated by Cd, Hg, Pb and Zn to varying degree. Industrial activities, agricultural activities and natural sources were identified as the potential sources determining the contents of trace metals in soils with contributions of 24.8%–24.9%, 33.3%–37.2% and 38.0%–41.8%, respectively. The slightly different results obtained from UNMIX and PMF might be caused by the estimations of uncertainty and different algorithms within the models. PMID:29474412

Carbon allocation, source-sink relations and plant growth: do we need to revise our carbon centric concepts?

NASA Astrophysics Data System (ADS)

Körner, Christian

2014-05-01

Since the discovery that plants 'eat air' 215 years ago, carbon supply was considered the largely unquestioned top driver of plant growth. The ease at which CO2 uptake (C source activity) can be measured, and the elegant algorithms that describe the responses of photosynthesis to light, temperature and CO2 concentration, explain why carbon driven growth and productivity became the starting point of all process based vegetation models. Most of these models, nowadays adopt other environmental drivers, such as nutrient availability, as modulating co-controls, but the carbon priority is retained. Yet, if we believe in the basic rules of stoichometry of all life, there is an inevitable need of 25-30 elements other then carbon, oxygen and hydrogen to build a healthy plant body. Plants compete for most of these elements, and their availability (except for N) is finite per unit land area. Hence, by pure plausibility, it is a highly unlikely situation that carbon plays the rate limiting role of growth under natural conditions, except in deep shade or on exceptionally fertile soils. Furthermore, water shortage and low temperature, both act directly upon tissue formation (meristems) long before photosynthetic limitations come into play. Hence, plants will incorporate C only to the extent other environmental drivers permit. In the case of nutrients and mature ecosystems, this sink control of plant growth may be masked in the short term by a tight, almost closed nutrient cycle or by widening the C to other element ratio. Because source and sink activity must match in the long term, it is not possible to identify the hierarchy of growth controls without manipulating the environment. Dry matter allocation to C rich structures and reserves may provide some stoichimetric leeway or periodic escapes from the more fundamental, long-term environmental controls of growth and productivity. I will explain why carbon centric explanations of growth are limited or arrive at plausible answers for the wrong reason. Suggested reading: Fatichi, Leuzinger, Körner (2013) Moving beyond photosynthesis: from carbon source to sink-driven vegetation modeling. New Phytologist. Körner C (2013) Growth controls photosynthesis - mostly. Nova Acta Leopoldina 391:273-283.

Size-Tuned Plastic Flow Localization in Irradiated Materials at the Submicron Scale

NASA Astrophysics Data System (ADS)

Cui, Yinan; Po, Giacomo; Ghoniem, Nasr

2018-05-01

Three-dimensional discrete dislocation dynamics (3D-DDD) simulations reveal that, with reduction of sample size in the submicron regime, the mechanism of plastic flow localization in irradiated materials transitions from irradiation-controlled to an intrinsic dislocation source controlled. Furthermore, the spatial correlation of plastic deformation decreases due to weaker dislocation interactions and less frequent cross slip as the system size decreases, thus manifesting itself in thinner dislocation channels. A simple model of discrete dislocation source activation coupled with cross slip channel widening is developed to reproduce and physically explain this transition. In order to quantify the phenomenon of plastic flow localization, we introduce a "deformation localization index," with implications to the design of radiation-resistant materials.

Effectiveness of an Internet Community for Severely Obese Women.

PubMed

Chomutare, Taridzo; Årsand, Eirik; Hartvigsen, Gunnar

2016-01-01

While Internet communities have become thriving sources of support, little is yet known about their effectiveness. We retrospectively sampled morbidly obese (Body Mass Index, BMI > 40) women who were active for at least a year in an Internet community. We compared self-reported weight changes between women who had high online participation levels (n = 71) versus those with low participation levels as control (n = 69). Women who actively participated online lost on average 7.52%, while those who were passive lost 5.39% of their original body weight. For active women, there was positive, albeit weak, correlation (r = 0.22, p < 0.05) between online participation levels and weight loss, while no significant correlation was noted for the control. Current results indicate modest evidence supporting active participation in Internet groups as an effective weight loss strategy for the target group.

Controlled activation of retrotransposition for plant breeding.

PubMed

Paszkowski, Jerzy

2015-04-01

Plant genomes consist to a large extent of transposable elements (TEs), predominantly retrotransposons. Their accumulation through periodic transposition bursts has shaped the structure and regulatory organization of plant genomes, often contributing to phenotypic traits. Transposon-generated phenotypes selected by humans during plant domestication have been maintained under strict selection during subsequent plant breeding. Our knowledge of the epigenetic, environmental, and developmental regulation of TE activity has advanced considerably in recent years. Here I will consider TEs as an attractive endogenous source of genetic variation that can be liberated in a controlled fashion and thus offer novel phenotypic diversity to be selected for crop improvement. Copyright © 2015 Elsevier Ltd. All rights reserved.

MEDICATION DISPOSAL AS A SOURCE FOR DRUGS AS ...

EPA Pesticide Factsheets

The major routes by which pharmaceuticals enter the environment are excretion, bathing, anddisposal of leftover, unwanted medications. Pharmaceuticals designed for humans and animalsoften remain unused. Leftover, accumulated drugs represent potentially environmentallyunsound disposal and suboptimal delivery of health care. They also can pose acute exposurerisks for humans and wildlife. Active pharmaceutical ingredients (APIs) directly enter theenvironment primarily via sewage. Among the three routes of entry, the relative contributions ofeach are poorly understood. In contrast to excretion, which as a source comprises continual lowlevelcontributions from multitudes of people, drug disposal comprises acute but transient andepisodic contributions from fewer people. The only route that is subject most easily to pollutionprevention or source control measures is disposal.A major unknown with respect to drugs as pollutants is what fractions of drug residues occurringin the ambient environment result from discarding leftover drugs. No studies exist that provideobjective data from well-defined populations to support any type of conclusion. Given theimportance of environmental stewardship to sustainability, a means for assessing the relativecontributions of APIs resulting from disposal would be useful in justifying the resources thatmight be devoted to controlling this source - - for example, by way of consumer

Unexpected dominance of parent-material strontium in a tropical forest on highly weathered soils

USGS Publications Warehouse

Bern, C.R.; Townsend, A.R.; Farmer, G.L.

2005-01-01

Controls over nutrient supply are key to understanding the structure and functioning of terrestrial ecosystems. Conceptual models once held that in situ mineral weathering was the primary long-term control over the availability of many plant nutrients, including the base cations calcium (Ca), magnesium (Mg), and potassium (K). Recent evidence has shown that atmospheric sources of these "rock-derived" nutrients can dominate actively cycling ecosystem pools, especially in systems on highly weathered soils. Such studies have relied heavily on the use of strontium isotopes as a proxy for base-cation cycling. Here we show that vegetation and soil-exchangeable pools of strontium in a tropical rainforest on highly weathered soils are still dominated by local rock sources. This pattern exists despite substantial atmospheric inputs of Sr, Ca, K, and Mg, and despite nearly 100% depletion of these elements from the top 1 m of soil. We present a model demonstrating that modest weathering inputs, resulting from tectonically driven erosion, could maintain parent-material dominance of actively cycling Sr. The majority of tropical forests are on highly weathered soils, but our results suggest that these forests may still show considerable variation in their primary sources of essential nutrients. ?? 2005 by the Ecological Society of America.

Detection of active noise control on the standard motorcycle exhaust Supra X 125 D using PVC pipe technique form Y

NASA Astrophysics Data System (ADS)

Isranuri, I.; Alfisyahrin; Nasution, A. R.

2018-02-01

This detection aims to obtain noise reduction on the supra X 125D motorcycle exhaust by using the Active Noise Control Method. The technique is done using a Y-shaped PVC pipe to be bolted on the exhaust, which then branch Y PVC is placed loudspeaker with impermeable conditions. The function of this loudspeaker is as a secondary noise to counter the primary noise of the sound of exhaust motorcycle Supra X 125D. The sound generator in this study is the ISD 4004 module, which serves to generate noise to counter the source noise. How this ISD 4004 module works is by recording source noise then recording the source noise and then reversed the phase 180° by phase reversing circuit. So that, the noise generated by the sound generator will hit the source noise and encounter or such as addition of two different phase of sound will result in noise reduction when detected at the end of the Y-shaped PVC pipe. Inverted phase reversed using feed-back resistor 1 kΩ and 2 kΩ input resistors, 16V capacitor 2500μf and as amplifier using ICL 7660 and TL 702 CP. Test results on the highest 1000 rpm rotation engine speed on the Z axis of 2 dB, and at the highest 2000 rpm rotation engine speed also occurs on the Z axis of 1.5 dB.

Innovative methodology for intercomparison of radionuclide calibrators using short half-life in situ prepared radioactive sources

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

Oliveira, P. A.; Santos, J. A. M., E-mail: joao.santos@ipoporto.min-saude.pt; Serviço de Física Médica do Instituto Português de Oncologia do Porto Francisco Gentil, EPE, Porto

2014-07-15

Purpose: An original radionuclide calibrator method for activity determination is presented. The method could be used for intercomparison surveys for short half-life radioactive sources used in Nuclear Medicine, such as{sup 99m}Tc or most positron emission tomography radiopharmaceuticals. Methods: By evaluation of the resulting net optical density (netOD) using a standardized scanning method of irradiated Gafchromic XRQA2 film, a comparison of the netOD measurement with a previously determined calibration curve can be made and the difference between the tested radionuclide calibrator and a radionuclide calibrator used as reference device can be calculated. To estimate the total expected measurement uncertainties, a carefulmore » analysis of the methodology, for the case of{sup 99m}Tc, was performed: reproducibility determination, scanning conditions, and possible fadeout effects. Since every factor of the activity measurement procedure can influence the final result, the method also evaluates correct syringe positioning inside the radionuclide calibrator. Results: As an alternative to using a calibrated source sent to the surveyed site, which requires a relatively long half-life of the nuclide, or sending a portable calibrated radionuclide calibrator, the proposed method uses a source preparedin situ. An indirect activity determination is achieved by the irradiation of a radiochromic film using {sup 99m}Tc under strictly controlled conditions, and cumulated activity calculation from the initial activity and total irradiation time. The irradiated Gafchromic film and the irradiator, without the source, can then be sent to a National Metrology Institute for evaluation of the results. Conclusions: The methodology described in this paper showed to have a good potential for accurate (3%) radionuclide calibrators intercomparison studies for{sup 99m}Tc between Nuclear Medicine centers without source transfer and can easily be adapted to other short half-life radionuclides.« less

Identification of hydrogeochemical processes and pollution sources of groundwater nitrate in Leiming Basin of Hainan island, Southern China

NASA Astrophysics Data System (ADS)

Shaowen, Y.; Zhan, Y., , Dr; Li, Q.

2017-12-01

Identifying the evolution of groundwater quality is important for the control and management of groundwater resources. The main aims of the present study are to identify the major factors affecting hydrogeochemistry of groundwater resources and to evaluate the potential sources of groundwater nitrate in Leiming basin using chemical and isotopic methods. The majority of samples belong to Na-Cl water type and are followed by Ca-HCO3 and mixed Ca-Na-HCO3. The δ18O and δ2H values in groundwater indicate that the shallow fissure groundwater is mainly recharged by rainfall. The evaporated surface water is another significant origin of groundwater. The weathering and dissolution of different rocks and minerals, input of precipitation, evaporation, ion exchange and anthropogenic activities, especially agricultural activities, influence the hydrogeochemistry of the study area. NO- 3 concentration in the groundwater varies from 0.7 to 51.7 mg/L and high values are mainly occurred in the densely populated area. The combined use of isotopic values and hydrochemical data suggests that the NO- 3 load in Leiming basin is not only derived from agricultural activities but also from other sources such as waste water and atmospheric deposition. Fertilizer is considered as the major source of NO- 3 in the groundwater in Leiming basin.

Seismic Monitoring of Permafrost During Controlled Thaw: An Active-Source Experiment Using a Surface Orbital Vibrator and Fiber-Optic DAS Arrays

NASA Astrophysics Data System (ADS)

Dou, S.; Wood, T.; Lindsey, N.; Ajo Franklin, J. B.; Freifeld, B. M.; Gelvin, A.; Morales, A.; Saari, S.; Ekblaw, I.; Wagner, A. M.; Daley, T. M.; Robertson, M.; Martin, E. R.; Ulrich, C.; Bjella, K.

2016-12-01

Thawing of permafrost can cause ground deformations that threaten the integrity of civil infrastructure. It is essential to develop early warning systems that can identify critically warmed permafrost and issue warnings for hazard prevention and control. Seismic methods can play a pivotal role in such systems for at least two reasons: First, seismic velocities are indicative of mechanical strength of the subsurface and thus are directly relevant to engineering properties; Second, seismic velocities in permafrost systems are sensitive to pre-thaw warming, which makes it possible to issue early warnings before the occurrence of hazardous subsidence events. However, several questions remain: What are the seismic signatures that can be effectively used for early warning of permafrost thaw? Can seismic methods provide enough warning times for hazard prevention and control? In this study, we investigate the feasibility of using permanently installed seismic networks for early warnings of permafrost thaw. We conducted continuous active-source seismic monitoring of permafrost that was under controlled heating at CRREL's Fairbanks permafrost experiment station. We used a permanently installed surface orbital vibrator (SOV) as source and surface-trenched DAS arrays as receivers. The SOV is characterized by its excellent repeatability, automated operation, high energy level, and the rich frequency content (10-100 Hz) of the generated wavefields. The fiber-optic DAS arrays allow continuous recording of seismic data with dense spatial sampling (1-meter channel spacing), low cost, and low maintenance. This combination of SOV-DAS provides unique seismic datasets for observing time-lapse changes of warming permafrost at the field scale, hence providing an observational basis for design and development of early warning systems for permafrost thaw.

Plant extracts as potential mosquito larvicides

PubMed Central

Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

2012-01-01

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

Plant extracts as potential mosquito larvicides.

PubMed

Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

2012-05-01

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

The Interplay Between Hardware and Control System Design in the Development of the Active Rack Isolation System

NASA Technical Reports Server (NTRS)

Fialho, Ian J.; Thampi, Sreekumar

2000-01-01

A primary mission of the International Space Station (ISS) is to provide a premier microgravity laboratory environment for conducting acceleration sensitive scientific research. In order to accomplish this goal, vibroacoustic disturbances caused by station activities that occur during the microgravity mode of operation, must be controlled. In addition to source isolation and other passive isolation methods, the ISS uses active isolation at the receiver, through the use of an Active Rack Isolation System (ARIS), as part of its overall vibration isolation strategy. A schematic diagram of a typical ARIS payload rack is shown. The ARIS isolation control system senses rack acceleration via three triaxial accelerometer heads and uses eight pushrod actuators to perform active vibration attenuation. Position sensors housed in the actuator assembly are used to sense the relative position between the rack and the station. Electrical power, data and other essential resources are routed through a set of umbilicals that interface with a passthrough panel at the bottom of the rack. A representative umbilical set is shown.

Medical catheters thermally manipulated by fiber optic bundles

DOEpatents

Chastagner, Philippe

1992-01-01

A maneuverable medical catheter comprising a flexible tube having a functional tip. The catheter is connected to a control source. The functional tip of the catheter carries a plurality of temperature activated elements arranged in parallel and disposed about the functional tip and held in spaced relation at each end. These elements expand when they are heated. A plurality of fiber optic bundles, each bundle having a proximal end attached to the control source and a distal end attached to one of the elements carry light into the elements where the light is absorbed as heat. By varying the optic fiber that is carrying the light and the intensity of the light, the bending of the elements can be controlled and thus the catheter steered. In an alternate embodiment, the catheter carries a medical instrument for gathering a sample of tissue. The instrument may also be deployed and operated by thermal expansion and contraction of its moving parts.

Modeling study of a proposed field calibration source using K-40 and high-Z targets for sodium iodide detectors

DOE PAGES

Rogers, Jeremy; Marianno, Craig; Kallenbach, Gene; ...

2016-06-01

Calibration sources based on the primordial isotope potassium-40 ( 40K) have reduced controls on the source’s activity due to its terrestrial ubiquity and very low specific activity. Potassium–40’s beta emissions and 1,460.8 keV gamma ray can be used to induce K-shell fluorescence x rays in high-Z metals between 60 and 80 keV. A gamma ray calibration source that uses potassium chloride salt and a high-Z metal to create a two-point calibration for a sodium iodide field gamma spectroscopy instrument is thus proposed. The calibration source was designed in collaboration with the Sandia National Laboratory using the Monte Carlo N-Particle eXtendedmore » (MCNPX) transport code. Two methods of x-ray production were explored. First, a thin high-Z layer (HZL) was interposed between the detector and the potassium chloride-urethane source matrix. Second, bismuth metal powder was homogeneously mixed with a urethane binding agent to form a potassium chloride-bismuth matrix (KBM). The bismuth-based source was selected as the development model because it is inexpensive, nontoxic, and outperforms the high-Z layer method in simulation. As a result, based on the MCNPX studies, sealing a mixture of bismuth powder and potassium chloride into a thin plastic case could provide a light, inexpensive field calibration source.« less

40 CFR 63.7832 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2011 CFR

2011-07-01

... and collect data to demonstrate continuous compliance? (a) Except for monitoring malfunctions, out-of... control activities (including as applicable, calibration checks and required zero and span adjustments... source is operating. (b) You may not use data recorded during monitoring malfunctions, associated repairs...

40 CFR 63.9922 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2013 CFR

2013-07-01

... demonstrate continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero... all times an affected source is operating. (b) You may not use data recorded during monitoring...

40 CFR 63.7832 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2013 CFR

2013-07-01

... and collect data to demonstrate continuous compliance? (a) Except for monitoring malfunctions, out-of... control activities (including as applicable, calibration checks and required zero and span adjustments... source is operating. (b) You may not use data recorded during monitoring malfunctions, associated repairs...

40 CFR 63.9922 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2014 CFR

2014-07-01

... demonstrate continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero... all times an affected source is operating. (b) You may not use data recorded during monitoring...

40 CFR 63.7832 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2014 CFR

2014-07-01

... and collect data to demonstrate continuous compliance? (a) Except for monitoring malfunctions, out-of... control activities (including as applicable, calibration checks and required zero and span adjustments... source is operating. (b) You may not use data recorded during monitoring malfunctions, associated repairs...

40 CFR 63.9633 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2013 CFR

2013-07-01

... continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including as applicable, calibration checks and required zero and span... affected source is operating. (b) You may not use data recorded during monitoring malfunctions, associated...

40 CFR 63.7832 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2010 CFR

2010-07-01

... and collect data to demonstrate continuous compliance? (a) Except for monitoring malfunctions, out-of... control activities (including as applicable, calibration checks and required zero and span adjustments... source is operating. (b) You may not use data recorded during monitoring malfunctions, associated repairs...

40 CFR 63.9922 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2012 CFR

2012-07-01

... demonstrate continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero... all times an affected source is operating. (b) You may not use data recorded during monitoring...

40 CFR 63.9922 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2010 CFR

2010-07-01

... demonstrate continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including, as applicable, calibration checks and required zero... all times an affected source is operating. (b) You may not use data recorded during monitoring...

40 CFR 63.7832 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2012 CFR

2012-07-01

... and collect data to demonstrate continuous compliance? (a) Except for monitoring malfunctions, out-of... control activities (including as applicable, calibration checks and required zero and span adjustments... source is operating. (b) You may not use data recorded during monitoring malfunctions, associated repairs...

40 CFR 63.9633 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2010 CFR

2010-07-01

... continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including as applicable, calibration checks and required zero and span... affected source is operating. (b) You may not use data recorded during monitoring malfunctions, associated...

40 CFR 63.9633 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2014 CFR

2014-07-01

... continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including as applicable, calibration checks and required zero and span... affected source is operating. (b) You may not use data recorded during monitoring malfunctions, associated...

40 CFR 63.9633 - How do I monitor and collect data to demonstrate continuous compliance?

Code of Federal Regulations, 2012 CFR

2012-07-01

... continuous compliance? (a) Except for monitoring malfunctions, associated repairs, and required quality assurance or control activities (including as applicable, calibration checks and required zero and span... affected source is operating. (b) You may not use data recorded during monitoring malfunctions, associated...

48 CFR 9.204 - Responsibilities for establishment of a qualification requirement.

Code of Federal Regulations, 2010 CFR

2010-10-01

... requirements. If active competition on anticipated future qualification requirements is likely to be fewer than... establishing the production, quality control, or other system to be tested and evaluated) for a small business... additional qualified sources or products are likely to result in cost savings from increased competition for...

Investigation of active structural intensity control in finite beams: theory and experiment

PubMed

Audrain; Masson; Berry

2000-08-01

An investigation of structural intensity control is presented in this paper. As opposed to previous work, the instantaneous intensity is completely taken into account in the control algorithm, i.e., all the terms are considered in the real-time control process and, in particular, the evanescent waves are considered in this approach. A finite difference approach using five accelerometers is used as the sensing scheme. A feedforward filtered-X least mean square algorithm is adapted to this energy-based control problem, involving a nonpositive definite quadratic form in general. In this respect, the approach is limited to cases where the geometry is such that the intensity component will have the same sign for the control source and the primary disturbance. Results from numerical simulations are first presented to illustrate the benefit of using a cost function based on structural intensity. Experimental validation of the approach is conducted on a free-free beam covered with viscoelastic material. A comparison is made between classical acceleration control and structural intensity control and the performance of both approaches is presented. These results confirm that using intensity control allows the error sensors to be placed closer to the control source and the primary disturbance, while preserving a good control performance.

Factors Associated With Exposure to Antismoking Information Among Adults in Vietnam, Global Adult Tobacco Survey, 2010

PubMed Central

Giang, Kim Bao; Nga, Pham Quynh; Hai, Phan Thi; Quan, Nguyen The; Tong, Van T.; Xuan, Le Thi Thanh; Hsia, Jason

2013-01-01

Introduction The media play a critical role in tobacco control. Knowledge about the exposure of a population to antismoking information can provide information for planning communication activities in tobacco control. We examined exposure to antismoking information associated with socioeconomic and demographic factors among adults (≥15 years) in Vietnam. Methods The Global Adult Tobacco Survey (GATS) is a nationally representative household survey of noninstitutionalized men and women aged 15 years or older and was conducted in Vietnam in 2010 (N = 9,925). We used GATS data on exposure to sources of antismoking information and analyzed associations among socioeconomic and demographic groups. Results An estimated 91.6% of the adult population was exposed to at least 1 source of antismoking information, and the mean number of sources of exposure was 3.7. Compared with their counterparts, respondents who were older, had higher education levels, higher economic status, and higher knowledge levels about the health consequences of smoking were more likely to be exposed to any source of antismoking information and to more informational sources. The most common source of exposure was television (85.9%). Respondents of higher social class (education, occupation, wealth) had more exposure through modern media sources (television), and respondents of lower social class were exposed to more traditional sources such as radio or loudspeakers. Conclusion Exposure to at least 1 source of antismoking information is high in Vietnam, and the number and type of source varied by sociodemographic group. Use of multiple communication channels is recommended to reinforce antismoking messages and to reach different groups in the population. PMID:24028833

Biofiltration: An innovative air pollution control technology for VOC emissions

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

Leson, G.; Winer, A.M.

1991-08-01

Biofiltration is a relatively recent air pollution control (APC) technology in which off-gases containing biodegradable volatile organic compounds (VOC) or inorganic air toxics are vented through a biologically active material. This technology has been successfully applied in Germany and The Netherlands in many full-scale applications to control odors, VOC and air toxic emissions from a wide range of industrial and public sector sources. Control efficiencies of more than 90 percent have been achieved for many common air pollutants. Due to lower operating costs, biofiltration can provide significant economic advantages over other APC technologies if applied to off-gases that contain readilymore » biodegradable pollutants in low concentrations. Environmental benefits include low energy requirements and the avoidance of cross media transfer of pollutants. This paper reviews the history and current status of biofiltration, outlines its underlying scientific and engineering principles, and discusses the applicability of biofilters for a wide range of specific emission sources.« less

An Integrated WRF-CAMx Modeling Approach for Impact Analysis of Implementing the Emergency PM2.5 Control Measures during Red Alerts in Beijing in December 2015

NASA Astrophysics Data System (ADS)

Jia, J.; Cheng, S.; Lei, L.; Lang, J.

2017-12-01

In December 2015, the Beijing-Tianjin-Hebei (BTH) region experienced several episodes of heavy air pollution. Beijing municipal government therefore issued 2 red alerts on December 7 and 19, respectively, and also implemented emergency control measures to alleviate the negative effects of pollution. It is estimated that the heavy pollutions in 2 red alert periods in Beijing were due mainly to the accumulation of air pollutants from local emission sources and the transboundary transport of pollutants from surrounding areas. The collected meteorological and PM2.5 data indicate that the severity of air pollutions were enlarged by the poor meteorological conditions along with lower mixing layer height. In this study, the WRF-CAMx modeling system was utilized not only for analyzing the contributions of PM2.5 from different sources, but also for quantitatively assessing the effects of implementing various emergency control measures on PM2.5 pollution control during the red alert periods. The modeling results show that local emissions were the most dominant contributors (64.8%-83.5%) among all emission sources, while the main external contributions came from the city of Baoding (3.4%-9.3%). In addition, among 5 different emission source categories, coal and traffic were the two dominant contributors to PM2.5 concentration in urban area of Beijing. Then four pollution control scenarios were designed particularly to investigate the effectiveness of the emergency control measures, and the results show that, generally these emergency control measures have positive effects on air pollution reduction. In particular, restrictive measures of traffic volume control and industrial activity shutdown/suspension have been found as the most effective measures in comparison to other emergency control measures. It is recommended that such effective measures should be considered to implement when next time similar heavy air pollutions occur in the city of Beijing.

Ecological response to climate change and human activities indicated by n-alkane proxy during the mid- to late Holocene: a case study from an alpine lake

NASA Astrophysics Data System (ADS)

Zhang, C.; Zhao, C.

2017-12-01

Paleolimonological records provide long-term dynamics information of past climate, environment, human activities and ecological variations and give evolutionary perspectives to understand responses process of ecological shift to internal or external trigger. In this study, a powerful biomarkers, n-alkanes, was used to reconstruct the past 5000 years organic matter sources and ecological evolution history of Beilianchi Lake in the southwestern of Loess Plateau after preliminary investigation of modern samples. Climate-environment change and human activities were also traced by total organic matter (TOC), magnetic susceptibility (MS) and relevant proxies. The results showed that the ecosystem related to organic matter composition in Beilianchi Lake might be mainly controlled by climate change before 1400 cal B.P., whereas after that, it was significantly influenced by soil erosion induced by increasing population and enhanced human activities. Lake ecosystem experienced periodical change from relatively stable stage with combination of allochthonous-autochthonous organic sources prior to 1400 cal B.P. to extremely instability and final return to steady state with allochthonous-dominant organic source since 300 cal B.P.. During the period of instability, organic matter composition during 1400-800 cal B.P. indicated a obvious bimodal distribution based on probability density distribution analysis, which reflected the lake ecosystem might stay at bistable state and switched repeatedly from more-macrophytes state (regime A with low ACL) towards less-macrophytes state (regime B with high ACL) controlled by disturbance of soil erosion. The flickering during this period could serve as the early warning signal of transition towards more-macrophytes state or less-macrophytes state in lake ecosystems.

Oscillatory support for rapid frequency change processing in infants.

PubMed

Musacchia, Gabriella; Choudhury, Naseem A; Ortiz-Mantilla, Silvia; Realpe-Bonilla, Teresa; Roesler, Cynthia P; Benasich, April A

2013-11-01

Rapid auditory processing and auditory change detection abilities are crucial aspects of speech and language development, particularly in the first year of life. Animal models and adult studies suggest that oscillatory synchrony, and in particular low-frequency oscillations play key roles in this process. We hypothesize that infant perception of rapid pitch and timing changes is mediated, at least in part, by oscillatory mechanisms. Using event-related potentials (ERPs), source localization and time-frequency analysis of event-related oscillations (EROs), we examined the neural substrates of rapid auditory processing in 4-month-olds. During a standard oddball paradigm, infants listened to tone pairs with invariant standard (STD, 800-800 Hz) and variant deviant (DEV, 800-1200 Hz) pitch. STD and DEV tone pairs were first presented in a block with a short inter-stimulus interval (ISI) (Rapid Rate: 70 ms ISI), followed by a block of stimuli with a longer ISI (Control Rate: 300 ms ISI). Results showed greater ERP peak amplitude in response to the DEV tone in both conditions and later and larger peaks during Rapid Rate presentation, compared to the Control condition. Sources of neural activity, localized to right and left auditory regions, showed larger and faster activation in the right hemisphere for both rate conditions. Time-frequency analysis of the source activity revealed clusters of theta band enhancement to the DEV tone in right auditory cortex for both conditions. Left auditory activity was enhanced only during Rapid Rate presentation. These data suggest that local low-frequency oscillatory synchrony underlies rapid processing and can robustly index auditory perception in young infants. Furthermore, left hemisphere recruitment during rapid frequency change discrimination suggests a difference in the spectral and temporal resolution of right and left hemispheres at a very young age. © 2013 Elsevier Ltd. All rights reserved.

Relative impact of emissions controls and meteorology on air pollution mitigation associated with the Asia-Pacific Economic Cooperation (APEC) conference in Beijing, China.

PubMed

Wang, Yuqin; Zhang, Yang; Schauer, James Jay; de Foy, Benjamin; Guo, Bo; Zhang, Yuanxun

2016-11-15

The Beijing government and its surrounding provinces implemented a series of measures to ensure haze-free skies during the 22(nd) Asia-Pacific Economic Cooperation (APEC) conference (November 10(th)-11(th), 2014). These measures included restrictions on traffic, construction, and industrial activity. Twelve hour measurements of the concentration and composition of ambient fine particulate matter (PM2.5) were performed for 5 consecutive months near the APEC conference site before (September 11(th)-November 2(nd), 2014), during (November 3(rd)-12(th), 2014) and after (November 13(th), 2014-January 31(st), 2015). The measurements are used in a positive matrix factorization model to determine the contributions from seven sources of PM2.5: secondary aerosols, traffic exhaust, industrial emission, road dust, soil dust, biomass burning and residual oil combustion. The source apportionment results are integrated with backward trajectory analysis using Weather Research and Forecast (WRF) meteorological simulations, which determine the relative influence of new regulation and meteorology upon improved air quality during the APEC conference. Data show that controls are very effective, but meteorology must be taken into account to determine the actual influence of the controls on pollution reduction. The industry source control is the most effective for reducing concentrations, followed by secondary aerosol and biomass controls, while the least effective control is for the residual oil combustion source. The largest reductions in concentrations occur when air mass transport is from the west-northwest (Ulanqab). Secondary aerosol and traffic exhaust reductions are most significant for air mass transport from the north-northwest (Xilingele League) origin, and least significant for northeast transport (Chifeng via Tangshan conditions). The largest reductions of soil dust, biomass burning, and industrial source are distinctly seen for Ulanqab conditions and least distinct for Xilingele League. Copyright © 2016 Elsevier B.V. All rights reserved.

Adsorbents for capturing mercury in coal-fired boiler flue gas.

PubMed

Yang, Hongqun; Xu, Zhenghe; Fan, Maohong; Bland, Alan E; Judkins, Roddie R

2007-07-19

This paper reviews recent advances in the research and development of sorbents used to capture mercury from coal-fired utility boiler flue gas. Mercury emissions are the source of serious health concerns. Worldwide mercury emissions from human activities are estimated to be 1000 to 6000 t/annum. Mercury emissions from coal-fired power plants are believed to be the largest source of anthropogenic mercury emissions. Mercury emissions from coal-fired utility boilers vary in total amount and speciation, depending on coal types, boiler operating conditions, and configurations of air pollution control devices (APCDs). The APCDs, such as fabric filter (FF) bag house, electrostatic precipitator (ESP), and wet flue gas desulfurization (FGD), can remove some particulate-bound and oxidized forms of mercury. Elemental mercury often escapes from these devices. Activated carbon injection upstream of a particulate control device has been shown to have the best potential to remove both elemental and oxidized mercury from the flue gas. For this paper, NORIT FGD activated carbon was extensively studied for its mercury adsorption behavior. Results from bench-, pilot- and field-scale studies, mercury adsorption by coal chars, and a case of lignite-burned mercury control were reviewed. Studies of brominated carbon, sulfur-impregnated carbon and chloride-impregnated carbon were also reviewed. Carbon substitutes, such as calcium sorbents, petroleum coke, zeolites and fly ash were analyzed for their mercury-adsorption performance. At this time, brominated activated carbon appears to be the best-performing mercury sorbent. A non-injection regenerable sorbent technology is briefly introduced herein, and the issue of mercury leachability is briefly covered. Future research directions are suggested.

Altered Cortical Swallowing Processing in Patients with Functional Dysphagia: A Preliminary Study

PubMed Central

Wollbrink, Andreas; Warnecke, Tobias; Winkels, Martin; Pantev, Christo; Dziewas, Rainer

2014-01-01

Objective Current neuroimaging research on functional disturbances provides growing evidence for objective neuronal correlates of allegedly psychogenic symptoms, thereby shifting the disease concept from a psychological towards a neurobiological model. Functional dysphagia is such a rare condition, whose pathogenetic mechanism is largely unknown. In the absence of any organic reason for a patient's persistent swallowing complaints, sensorimotor processing abnormalities involving central neural pathways constitute a potential etiology. Methods In this pilot study we measured cortical swallow-related activation in 5 patients diagnosed with functional dysphagia and a matched group of healthy subjects applying magnetoencephalography. Source localization of cortical activation was done with synthetic aperture magnetometry. To test for significant differences in cortical swallowing processing between groups, a non-parametric permutation test was afterwards performed on individual source localization maps. Results Swallowing task performance was comparable between groups. In relation to control subjects, in whom activation was symmetrically distributed in rostro-medial parts of the sensorimotor cortices of both hemispheres, patients showed prominent activation of the right insula, dorsolateral prefrontal cortex and lateral premotor, motor as well as inferolateral parietal cortex. Furthermore, activation was markedly reduced in the left medial primary sensory cortex as well as right medial sensorimotor cortex and adjacent supplementary motor area (p<0.01). Conclusions Functional dysphagia - a condition with assumed normal brain function - seems to be associated with distinctive changes of the swallow-related cortical activation pattern. Alterations may reflect exaggerated activation of a widely distributed vigilance, self-monitoring and salience rating network that interferes with down-stream deglutition sensorimotor control. PMID:24586948

Tuberculosis in the tropics.

PubMed

Krause, V L; Britton, W J

1993-09-20

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

The Fate of Trace Contaminants in a Crewed Spacecraft Cabin Environment

NASA Technical Reports Server (NTRS)

Perry, Jay L.; Kayatin, Matthew J.

2016-01-01

Trace chemical contaminants produced via equipment offgassing, human metabolic sources, and vehicle operations are removed from the cabin atmosphere by active contamination control equipment and incidental removal by other air quality control equipment. The fate of representative trace contaminants commonly observed in spacecraft cabin atmospheres is explored. Removal mechanisms are described and predictive mass balance techniques are reviewed. Results from the predictive techniques are compared to cabin air quality analysis results. Considerations are discussed for an integrated trace contaminant control architecture suitable for long duration crewed space exploration missions.

Experience of disused source management in Latin America

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

Pimenta Mourao, R.

2008-07-01

The Centro de Desenvolvimento da Tecnologia Nuclear (Center for the Development of Nuclear Technology) - CDTN - has been actively engaged in cooperation programs for disused source management throughout the Latin American and the Caribbean region since 1996. The CDTN source conditioning team participated in the preparation of the technical procedures established for the different tasks involved in the radium sources conditioning operations, like preparation of the packaging for conditioning; sources conditioning; capsule welding; leak test in radium-containing capsule; and radiation protection planning for the conditioning of disused radium sources. The team also carried out twelve radium sources conditioning operationmore » in the region, besides in-house operations, which resulted in a total conditioned activity of approximately 525 GBq, or 14,200 mg of radium. Additionally, one operation was carried out in Nicaragua to safely condition three Cobalt teletherapy heads stored under very precarious conditions in the premises of an old hospital. More recently, the team started its participation in an IAEA- and US State Department-sponsored program for the repatriation of disused or excess transuranic sources presently stored at users' premises or under regulatory control in different countries in the region. In September 2007 the team attended a theoretical and practical training in transuranic sources management, including the participation in the conditioning of different neutron sources in certified packages. It is expected that the trained team will carry out similar operations in other Latin American countries. Finally, the team is expected be involved in the near future in the repatriation of US-origin teletherapy heads and industrial gauges. (authors)« less

Toward Active X-ray Telescopes II

NASA Technical Reports Server (NTRS)

O'Dell, Stephen L.; Aldroft, Thomas L.; Atkins, Carolyn; Button, Timothy W.; Cotroneo, Vincenzo; Davis, William N.; Doel, Peter; Feldman, Charlotte H.; Freeman, Mark D.; Gubarev, Mikhail V.;

Comprehensive Design Reliability Activities for Aerospace Propulsion Systems

NASA Technical Reports Server (NTRS)

Christenson, R. L.; Whitley, M. R.; Knight, K. C.

2000-01-01

This technical publication describes the methodology, model, software tool, input data, and analysis result that support aerospace design reliability studies. The focus of these activities is on propulsion systems mechanical design reliability. The goal of these activities is to support design from a reliability perspective. Paralleling performance analyses in schedule and method, this requires the proper use of metrics in a validated reliability model useful for design, sensitivity, and trade studies. Design reliability analysis in this view is one of several critical design functions. A design reliability method is detailed and two example analyses are provided-one qualitative and the other quantitative. The use of aerospace and commercial data sources for quantification is discussed and sources listed. A tool that was developed to support both types of analyses is presented. Finally, special topics discussed include the development of design criteria, issues of reliability quantification, quality control, and reliability verification.

The Stellar Imager (SI) Project: Resolving Stellar Surfaces, Interiors, and Magnetic Activity

NASA Technical Reports Server (NTRS)

Carpenter, Kenneth G.; Schrijver, K.; Karovska, M.

2007-01-01

The Stellar Imager (SI) is a UV/Optical. Space-Based Interferometer designed to enable 0.1 milli-arcsec (mas) spectral imaging of stellar surfaces and, via asteroseismology, stellar interiors and of the Universe in general. The ultra-sharp images of SI will revolutionize our view of many dynamic astrophysical processes by transforming point sources into extended sources, and snapshots into evolving views. The science of SI focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. Its prime goal is to enable long-term forecasting of solar activity and the space weather that it drives. SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes in the Universe. In this paper we discuss the science goals, technology needs, and baseline design of the SI mission.

Lateralization as a symmetry breaking process in birdsong

NASA Astrophysics Data System (ADS)

Trevisan, M. A.; Cooper, B.; Goller, F.; Mindlin, G. B.

2007-03-01

The singing by songbirds is a most convincing example in the animal kingdom of functional lateralization of the brain, a feature usually associated with human language. Lateralization is expressed as one or both of the bird’s sound sources being active during the vocalization. Normal songs require high coordination between the vocal organ and respiratory activity, which is bilaterally symmetric. Moreover, the physical and neural substrate used to produce the song lack obvious asymmetries. In this work we show that complex spatiotemporal patterns of motor activity controlling airflow through the sound sources can be explained in terms of spontaneous symmetry breaking bifurcations. This analysis also provides a framework from which to study the effects of imperfections in the system’ s symmetries. A physical model of the avian vocal organ is used to generate synthetic sounds, which allows us to predict acoustical signatures of the song and compare the predictions of the model with experimental data.

SI: The Stellar Imager

NASA Technical Reports Server (NTRS)

Carpenter, Kenneth G.; Schrijver, Carolus J.; Karovska, Margarita

2006-01-01

The ultra-sharp images of the Stellar Imager (SI) will revolutionize our view of many dynamic astrophysical processes: The 0.1 milliarcsec resolution of this deep-space telescope will transform point sources into extended sources, and simple snapshots into spellbinding evolving views. SI s science focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. SI s prime goal is to enable long-term forecasting of solar activity and the space weather that it drives in support of the Living With a Star program in the Exploration Era by imaging a sample of magnetically active stars with enough resolution to map their evolving dynamo patterns and their internal flows. By exploring the Universe at ultra-high resolution, SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magnetohydrodynamically controlled structures and processes in the Universe.

Application of chemometric analysis based on physicochemical and chromatographic data for the differentiation origin of plant protection products containing chlorpyrifos.

PubMed

Miszczyk, Marek; Płonka, Marlena; Bober, Katarzyna; Dołowy, Małgorzata; Pyka, Alina; Pszczolińska, Klaudia

2015-01-01

The aim of this study was to investigate the similarities and dissimilarities between the pesticide samples in form of emulsifiable concentrates (EC) formulation containing chlorpyrifos as active ingredient coming from different sources (i.e., shops and wholesales) and also belonging to various series. The results obtained by the Headspace Gas Chromatography-Mass Spectrometry method and also some selected physicochemical properties of examined pesticides including pH, density, stability, active ingredient and water content in pesticides tested were compared using two chemometric methods. Applicability of simple cluster analysis and also principal component analysis of obtained data in differentiation of examined plant protection products coming from different sources was confirmed. It would be advantageous in the routine control of originality and also in the detection of counterfeit pesticides, respectively, among commercially available pesticides containing chlorpyrifos as an active ingredient.

Disturbance Source Separation in Shear Flows Using Blind Source Separation Methods

NASA Astrophysics Data System (ADS)

Gluzman, Igal; Cohen, Jacob; Oshman, Yaakov

2017-11-01

A novel approach is presented for identifying disturbance sources in wall-bounded shear flows. The method can prove useful for active control of boundary layer transition from laminar to turbulent flow. The underlying idea is to consider the flow state, as measured in sensors, to be a mixture of sources, and to use Blind Source Separation (BSS) techniques to recover the separate sources and their unknown mixing process. We present a BSS method based on the Degenerate Unmixing Estimation Technique. This method can be used to identify any (a priori unknown) number of sources by using the data acquired by only two sensors. The power of the new method is demonstrated via numerical and experimental proofs of concept. Wind tunnel experiments involving boundary layer flow over a flat plate were carried out, in which two hot-wire anemometers were used to separate disturbances generated by disturbance generators such as a single dielectric barrier discharge plasma actuator and a loudspeaker.

Phase 3 experiments of the JAERI/USDOE collaborative program on fusion blanket neutronics. Volume 1: Experiment

NASA Astrophysics Data System (ADS)

Oyama, Yukio; Konno, Chikara; Ikeda, Yujiro; Maekawa, Fujio; Kosako, Kazuaki; Nakamura, Tomoo; Maekawa, Hiroshi; Youssef, Mahmoud Z.; Kumar, Anil; Abdou, Mohamed A.

1994-02-01

A pseudo-line source has been realized by using an accelerator based D-T point neutron source. The pseudo-line source is obtained by time averaging of continuously moving point source or by superposition of finely distributed point sources. The line source is utilized for fusion blanket neutronics experiments with an annular geometry so as to simulate a part of a tokamak reactor. The source neutron characteristics were measured for two operational modes for the line source, continuous and step-wide modes, with the activation foil and the NE213 detectors, respectively. In order to give a source condition for a successive calculational analysis on the annular blanket experiment, the neutron source characteristics was calculated by a Monte Carlo code. The reliability of the Monte Carlo calculation was confirmed by comparison with the measured source characteristics. The shape of the annular blanket system was a rectangular with an inner cavity. The annular blanket was consist of 15 mm-thick first wall (SS304) and 406 mm-thick breeder zone with Li2O at inside and Li2CO3 at outside. The line source was produced at the center of the inner cavity by moving the annular blanket system in the span of 2 m. Three annular blanket configurations were examined; the reference blanket, the blanket covered with 25 mm thick graphite armor and the armor-blanket with a large opening. The neutronics parameters of tritium production rate, neutron spectrum and activation reaction rate were measured with specially developed techniques such as multi-detector data acquisition system, spectrum weighting function method and ramp controlled high voltage system. The present experiment provides unique data for a higher step of benchmark to test a reliability of neutronics design calculation for a realistic tokamak reactor.

Effects of whole flaxseed, raw soybeans, and calcium salts of fatty acids on measures of cellular immune function of transition dairy cows.

PubMed

Gandra, J R; Barletta, R V; Mingoti, R D; Verdurico, L C; Freitas, J E; Oliveira, L J; Takiya, C S; Kfoury, J R; Wiltbank, M C; Renno, F P

2016-06-01

The objective of the current study was to evaluate the effects of supplemental n-3 and n-6 fatty acid (FA) sources on cellular immune function of transition dairy cows. Animals were randomly assigned to receive 1 of 4 diets: control (n=11); whole flaxseed (n-3 FA source; n=11), 60 and 80g/kg of whole flaxseed [diet dry matter (DM) basis] during pre- and postpartum, respectively; whole raw soybeans (n-6 FA source; n=10), 120 and 160g/kg of whole raw soybeans (diet DM basis) during pre- and postpartum, respectively; and calcium salts of unsaturated FA (Megalac-E, n-6 FA source; n=10), 24 and 32g/kg of calcium salts of unsaturated FA (diet DM basis) during pre- and postpartum, respectively. Supplemental FA did not alter DM intake and milk yield but increased energy balance during the postpartum period. Diets containing n-3 and n-6 FA sources increased phagocytosis capacity of leukocytes and monocytes and phagocytosis activity of monocytes. Furthermore, n-3 FA source increased phagocytic capacity of leukocytes and neutrophils and increased phagocytic activity in monocytes and neutrophils when compared with n-6 FA sources. Supplemental FA effects on adaptive immune system included increased percentage of T-helper cells, T-cytotoxic cells, cells that expressed IL-2 receptors, and CD62 adhesion molecules. The results of this study suggest that unsaturated FA can modulate innate and adaptive cellular immunity and trigger a proinflammatory response. The n-3 FA seems to have a greater effect on phagocytic capacity and activity of leukocytes when compared with n-6 FA. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Lateral prefrontal cortex activity during cognitive control of emotion predicts response to social stress in schizophrenia

PubMed Central

Tully, Laura M.; Lincoln, Sarah Hope; Hooker, Christine I.

2014-01-01

LPFC dysfunction is a well-established neural impairment in schizophrenia and is associated with worse symptoms. However, how LPFC activation influences symptoms is unclear. Previous findings in healthy individuals demonstrate that lateral prefrontal cortex (LPFC) activation during cognitive control of emotional information predicts mood and behavior in response to interpersonal conflict, thus impairments in these processes may contribute to symptom exacerbation in schizophrenia. We investigated whether schizophrenia participants show LPFC deficits during cognitive control of emotional information, and whether these LPFC deficits prospectively predict changes in mood and symptoms following real-world interpersonal conflict. During fMRI, 23 individuals with schizophrenia or schizoaffective disorder and 24 healthy controls completed the Multi-Source Interference Task superimposed on neutral and negative pictures. Afterwards, schizophrenia participants completed a 21-day online daily-diary in which they rated the extent to which they experienced mood and schizophrenia-spectrum symptoms, as well as the occurrence and response to interpersonal conflict. Schizophrenia participants had lower dorsal LPFC activity (BA9) during cognitive control of task-irrelevant negative emotional information. Within schizophrenia participants, DLPFC activity during cognitive control of emotional information predicted changes in positive and negative mood on days following highly distressing interpersonal conflicts. Results have implications for understanding the specific role of LPFC in response to social stress in schizophrenia, and suggest that treatments targeting LPFC-mediated cognitive control of emotion could promote adaptive response to social stress in schizophrenia. PMID:25379415

Model-based Bayesian signal extraction algorithm for peripheral nerves

NASA Astrophysics Data System (ADS)

Eggers, Thomas E.; Dweiri, Yazan M.; McCallum, Grant A.; Durand, Dominique M.

2017-10-01

Objective. Multi-channel cuff electrodes have recently been investigated for extracting fascicular-level motor commands from mixed neural recordings. Such signals could provide volitional, intuitive control over a robotic prosthesis for amputee patients. Recent work has demonstrated success in extracting these signals in acute and chronic preparations using spatial filtering techniques. These extracted signals, however, had low signal-to-noise ratios and thus limited their utility to binary classification. In this work a new algorithm is proposed which combines previous source localization approaches to create a model based method which operates in real time. Approach. To validate this algorithm, a saline benchtop setup was created to allow the precise placement of artificial sources within a cuff and interference sources outside the cuff. The artificial source was taken from five seconds of chronic neural activity to replicate realistic recordings. The proposed algorithm, hybrid Bayesian signal extraction (HBSE), is then compared to previous algorithms, beamforming and a Bayesian spatial filtering method, on this test data. An example chronic neural recording is also analyzed with all three algorithms. Main results. The proposed algorithm improved the signal to noise and signal to interference ratio of extracted test signals two to three fold, as well as increased the correlation coefficient between the original and recovered signals by 10-20%. These improvements translated to the chronic recording example and increased the calculated bit rate between the recovered signals and the recorded motor activity. Significance. HBSE significantly outperforms previous algorithms in extracting realistic neural signals, even in the presence of external noise sources. These results demonstrate the feasibility of extracting dynamic motor signals from a multi-fascicled intact nerve trunk, which in turn could extract motor command signals from an amputee for the end goal of controlling a prosthetic limb.

Mission Control Center (MCC) system specification for the shuttle Orbital Flight Test (OFT) timeframe

NASA Technical Reports Server (NTRS)

1978-01-01

The Mission Control Center Shuttle (MCC) Shuttle Orbital Flight Test (OFT) Data System (OFTDS) provides facilities for flight control and data systems personnel to monitor and control the Shuttle flights from launch (tower clear) to rollout (wheels stopped on runway). It also supports the preparation for flight (flight planning, flight controller and crew training, and integrated vehicle and network testing activities). The MCC Shuttle OFTDS is described in detail. Three major support systems of the OFTDS and the data types and sources of data entering or exiting the MCC were illustrated. These systems are the communication interface system, the data computation complex, and the display and control system.

Remember the source: dissociating frontal and parietal contributions to episodic memory.

PubMed

Donaldson, David I; Wheeler, Mark E; Petersen, Steve E

2010-02-01

Event-related fMRI studies reveal that episodic memory retrieval modulates lateral and medial parietal cortices, dorsal middle frontal gyrus (MFG), and anterior PFC. These regions respond more for recognized old than correctly rejected new words, suggesting a neural correlate of retrieval success. Despite significant efforts examining retrieval success regions, their role in retrieval remains largely unknown. Here we asked the question, to what degree are the regions performing memory-specific operations? And if so, are they all equally sensitive to successful retrieval, or are other factors such as error detection also implicated? We investigated this question by testing whether activity in retrieval success regions was associated with task-specific contingencies (i.e., perceived targetness) or mnemonic relevance (e.g., retrieval of source context). To do this, we used a source memory task that required discrimination between remembered targets and remembered nontargets. For a given region, the modulation of neural activity by a situational factor such as target status would suggest a more domain-general role; similarly, modulations of activity linked to error detection would suggest a role in monitoring and control rather than the accumulation of evidence from memory per se. We found that parietal retrieval success regions exhibited greater activity for items receiving correct than incorrect source responses, whereas frontal retrieval success regions were most active on error trials, suggesting that posterior regions signal successful retrieval whereas frontal regions monitor retrieval outcome. In addition, perceived targetness failed to modulate fMRI activity in any retrieval success region, suggesting that these regions are retrieval specific. We discuss the different functions that these regions may support and propose an accumulator model that captures the different pattern of responses seen in frontal and parietal retrieval success regions.

Storm water management in an urban catchment: effects of source control and real-time management of sewer systems on receiving water quality.

PubMed

Frehmann, T; Nafo, I; Niemann, A; Geiger, W F

2002-01-01

For the examination of the effects of different storm water management strategies in an urban catchment area on receiving water quality, an integrated simulation of the sewer system, wastewater treatment plant and receiving water is carried out. In the sewer system real-time control measures are implemented. As examples of source control measures the reduction of wastewater and the reduction of the amount of impervious surfaces producing storm water discharges are examined. The surface runoff calculation and the simulation of the sewer system and the WWTP are based on a MATLAB/SIMULINK simulation environment. The impact of the measures on the receiving water is simulated using AQUASIM. It can be shown that the examined storm water management measures, especially the source control measures, can reduce the combined sewer overflow volume and the pollutant discharge load considerably. All examined measures also have positive effects on the receiving water quality. Moreover, the reduction of impervious surfaces avoids combined sewer overflow activities, and in consequence prevents pollutants from discharging into the receiving water after small rainfall events. However, the receiving water quality improvement may not be seen as important enough to avoid acute receiving water effects in general.

Sedimentation as a Control for Large Submarine Landslides: Mechanical Modeling and Analysis of the Santa Barbara Basin

NASA Astrophysics Data System (ADS)

Stoecklin, A.; Friedli, B.; Puzrin, A. M.

2017-11-01

The volume of submarine landslides is a key controlling factor for their damage potential. Particularly large landslides are found in active sedimentary regions. However, the mechanism controlling their volume, and in particular their thickness, remains unclear. Here we present a mechanism that explains how rapid sedimentation can lead to localized slope failure at a preferential depth and set the conditions for the emergence of large-scale slope-parallel landslides. We account for the contractive shearing behavior of the sediments, which locally accelerates the development of overpressures in the pore fluid, even on very mild slopes. When applied to the Santa Barbara basin, the mechanism offers an explanation for the regional variation in landslide thickness and their sedimentation-controlled recurrence. Although earthquakes are the most likely trigger for these mass movements, our results suggest that the sedimentation process controls the geometry of their source region. The mechanism introduced here is generally applicable and can provide initial conditions for subsequent landslide triggering, runout, and tsunami-source analyses in sedimentary regions.

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

PubMed

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

2012-05-01

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

Active Control of Aerodynamic Noise Sources

NASA Technical Reports Server (NTRS)

Reynolds, Gregory A.

2001-01-01

Aerodynamic noise sources become important when propulsion noise is relatively low, as during aircraft landing. Under these conditions, aerodynamic noise from high-lift systems can be significant. The research program and accomplishments described here are directed toward reduction of this aerodynamic noise. Progress toward this objective include correction of flow quality in the Low Turbulence Water Channel flow facility, development of a test model and traversing mechanism, and improvement of the data acquisition and flow visualization capabilities in the Aero. & Fluid Dynamics Laboratory. These developments are described in this report.

Single Active Switch PV Inverter

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

Ramanan, V. R.; Pan, Zhiguo

This report presents a new PV inverter topology that uses only one active switch instead of 7 active switches in a conventional PV inverter. It has a buck boost converter and operates at discontinuous current control mode, which can reduce the output stage from an active switch bridge to a thyristor bridge. This concept, if successfully demonstrated, may have great cost and size/weight benefits over conventional solutions. Since the proposed topology is completely different from the traditional boost converter plus voltage source inverter approach, there is no existing control/modulation scheme available. A new modulation scheme for both the main switchmore » and the thyristors has been developed. An active clamping circuit has also been proposed to reduce switching losses and voltage spike during the switching transient. A simulation model has been set up to validate the control algorithm and clamping circuit. Simulated results show that a proposed 10 kW PV inverter can reach 5% total harmonic distortion (THD), 98.8% peak efficiency with only one main active switch, and an inductor weighing less than 3 kg. Based on that, a 10 kW prototype converter has been designed and built.« less

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

Simpson, L.

ITN Energy Systems, Inc., and Global Solar Energy, Inc., with the assistance of NREL's PV Manufacturing R&D program, have continued the advancement of CIGS production technology through the development of trajectory-oriented predictive/control models, fault-tolerance control, control-platform development, in-situ sensors, and process improvements. Modeling activities to date include the development of physics-based and empirical models for CIGS and sputter-deposition processing, implementation of model-based control, and application of predictive models to the construction of new evaporation sources and for control. Model-based control is enabled through implementation of reduced or empirical models into a control platform. Reliability improvement activities include implementation of preventivemore » maintenance schedules; detection of failed sensors/equipment and reconfiguration to continue processing; and systematic development of fault prevention and reconfiguration strategies for the full range of CIGS PV production deposition processes. In-situ sensor development activities have resulted in improved control and indicated the potential for enhanced process status monitoring and control of the deposition processes. Substantial process improvements have been made, including significant improvement in CIGS uniformity, thickness control, efficiency, yield, and throughput. In large measure, these gains have been driven by process optimization, which, in turn, have been enabled by control and reliability improvements due to this PV Manufacturing R&D program. This has resulted in substantial improvements of flexible CIGS PV module performance and efficiency.« less

Independent Component Analysis-motivated Approach to Classificatory Decomposition of Cortical Evoked Potentials

PubMed Central

Smolinski, Tomasz G; Buchanan, Roger; Boratyn, Grzegorz M; Milanova, Mariofanna; Prinz, Astrid A

2006-01-01

Background Independent Component Analysis (ICA) proves to be useful in the analysis of neural activity, as it allows for identification of distinct sources of activity. Applied to measurements registered in a controlled setting and under exposure to an external stimulus, it can facilitate analysis of the impact of the stimulus on those sources. The link between the stimulus and a given source can be verified by a classifier that is able to "predict" the condition a given signal was registered under, solely based on the components. However, the ICA's assumption about statistical independence of sources is often unrealistic and turns out to be insufficient to build an accurate classifier. Therefore, we propose to utilize a novel method, based on hybridization of ICA, multi-objective evolutionary algorithms (MOEA), and rough sets (RS), that attempts to improve the effectiveness of signal decomposition techniques by providing them with "classification-awareness." Results The preliminary results described here are very promising and further investigation of other MOEAs and/or RS-based classification accuracy measures should be pursued. Even a quick visual analysis of those results can provide an interesting insight into the problem of neural activity analysis. Conclusion We present a methodology of classificatory decomposition of signals. One of the main advantages of our approach is the fact that rather than solely relying on often unrealistic assumptions about statistical independence of sources, components are generated in the light of a underlying classification problem itself. PMID:17118151

Tracking the voluntary control of auditory spatial attention with event-related brain potentials.

PubMed

Störmer, Viola S; Green, Jessica J; McDonald, John J

2009-03-01

A lateralized event-related potential (ERP) component elicited by attention-directing cues (ADAN) has been linked to frontal-lobe control but is often absent when spatial attention is deployed in the auditory modality. Here, we tested the hypothesis that ERP activity associated with frontal-lobe control of auditory spatial attention is distributed bilaterally by comparing ERPs elicited by attention-directing cues and neutral cues in a unimodal auditory task. This revealed an initial ERP positivity over the anterior scalp and a later ERP negativity over the parietal scalp. Distributed source analysis indicated that the anterior positivity was generated primarily in bilateral prefrontal cortices, whereas the more posterior negativity was generated in parietal and temporal cortices. The anterior ERP positivity likely reflects frontal-lobe attentional control, whereas the subsequent ERP negativity likely reflects anticipatory biasing of activity in auditory cortex.

Plasmonic beaming and active control over fluorescent emission.

PubMed

Jun, Young Chul; Huang, Kevin C Y; Brongersma, Mark L

2011-01-01

Nanometallic optical antennas are rapidly gaining popularity in applications that require exquisite control over light concentration and emission processes. The search is on for high-performance antennas that offer facile integration on chips. Here we demonstrate a new, easily fabricated optical antenna design that achieves an unprecedented level of control over fluorescent emission by combining concepts from plasmonics, radiative decay engineering and optical beaming. The antenna consists of a nanoscale plasmonic cavity filled with quantum dots coupled to a miniature grating structure that can be engineered to produce one or more highly collimated beams. Electromagnetic simulations and confocal microscopy were used to visualize the beaming process. The metals defining the plasmonic cavity can be utilized to electrically control the emission intensity and wavelength. These findings facilitate the realization of a new class of active optical antennas for use in new optical sources and a wide range of nanoscale optical spectroscopy applications.

Topography, power, and current source density of θ oscillations during reward processing as markers for alcohol dependence.

PubMed

Kamarajan, Chella; Rangaswamy, Madhavi; Manz, Niklas; Chorlian, David B; Pandey, Ashwini K; Roopesh, Bangalore N; Porjesz, Bernice

2012-05-01

Recent studies have linked alcoholism with a dysfunctional neural reward system. Although several electrophysiological studies have explored reward processing in healthy individuals, such studies in alcohol-dependent individuals are quite rare. The present study examines theta oscillations during reward processing in abstinent alcoholics. The electroencephalogram (EEG) was recorded in 38 abstinent alcoholics and 38 healthy controls as they performed a single outcome gambling task, which involved outcomes of either loss or gain of an amount (10 or 50¢) that was bet. Event-related theta band (3.0-7.0 Hz) power following each outcome stimulus was computed using the S-transform method. Theta power at the time window of the outcome-related negativity (ORN) and positivity (ORP) (200-500 ms) was compared across groups and outcome conditions. Additionally, behavioral data of impulsivity and task performance were analyzed. The alcoholic group showed significantly decreased theta power during reward processing compared to controls. Current source density (CSD) maps of alcoholics revealed weaker and diffuse source activity for all conditions and weaker bilateral prefrontal sources during the Loss 50 condition when compared with controls who manifested stronger and focused midline sources. Furthermore, alcoholics exhibited increased impulsivity and risk-taking on the behavioral measures. A strong association between reduced anterior theta power and impulsive task-performance was observed. It is suggested that decreased power and weaker and diffuse CSD in alcoholics may be due to dysfunctional neural reward circuitry. The relationship among alcoholism, theta oscillations, reward processing, and impulsivity could offer clues to understand brain circuitries that mediate reward processing and inhibitory control. Copyright © 2011 Wiley-Liss, Inc.

Topography, Power and Current Source Density of Theta Oscillations during Reward Processing as Markers for Alcohol Dependence

PubMed Central

Kamarajan, Chella; Rangaswamy, Madhavi; Manz, Niklas; Chorlian, David B.; Pandey, Ashwini K.; Roopesh, Bangalore N.; Porjesz, Bernice

2013-01-01

Recent studies have linked alcoholism with a dysfunctional neural reward system. Although several electrophysiological studies have explored reward processing in healthy individuals, such studies in alcohol dependent individuals are quite rare. The present study examines theta oscillations during reward processing in abstinent alcoholics. The electroencephalogram (EEG) was recorded in 38 abstinent alcoholics and 38 healthy controls as they performed a single outcome gambling task which involved outcomes of either loss or gain of an amount (10¢ or 50¢) that was bet. Event-related theta band (3.0–7.0 Hz) power following each outcome stimulus was computed using the S-transform method. Theta power at the time window of the outcome-related negativity (ORN) and positivity (ORP) (200–500 ms) was compared across groups and outcome conditions. Additionally, behavioral data of impulsivity and task performance were analyzed. The alcoholic group showed significantly decreased theta power during reward processing compared to controls. Current Source Density (CSD) maps of alcoholics revealed weaker and diffuse source activity for all conditions and weaker bilateral prefrontal sources during the Loss 50 condition as compared to controls who manifested stronger and focused midline sources. Further, alcoholics exhibited increased impulsivity and risk-taking on the behavioral measures. A strong association between reduced anterior theta power and impulsive task-performance was observed. It is suggested that decreased power and weaker and diffuse CSD in alcoholics may be due to dysfunctional neural reward circuitry. The relationship among alcoholism, theta oscillations, reward processing and impulsivity could offer clues to understand brain circuitries that mediate reward processing and inhibitory control. PMID:21520344

Sources, transformations, and hydrological processes that control stream nitrate and dissolved organic matter concentrations during snowmelt in an upland forest

USGS Publications Warehouse

Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.; Kendall, Carol; Doctor, Daniel H.; Aiken, George R.; Ohte, Nobuhito

2008-01-01

We explored catchment processes that control stream nutrient concentrations at an upland forest in northeastern Vermont, USA, where inputs of nitrogen via atmospheric deposition are among the highest in the nation and affect ecosystem functioning. We traced sources of water, nitrate, and dissolved organic matter (DOM) using stream water samples collected at high frequency during spring snowmelt. Hydrochemistry, isotopic tracers, and end‐member mixing analyses suggested the timing, sources, and source areas from which water and nutrients entered the stream. Although stream‐dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) both originated from leaching of soluble organic matter, flushing responses between these two DOM components varied because of dynamic shifts of hydrological flow paths and sources that supply the highest concentrations of DOC and DON. High concentrations of stream water nitrate originated from atmospheric sources as well as nitrified sources from catchment soils. We detected nitrification in surficial soils during late snowmelt which affected the nitrate supply that was available to be transported to streams. However, isotopic tracers showed that the majority of nitrate in upslope surficial soil waters after the onset of snowmelt originated from atmospheric sources. A fraction of the atmospheric nitrogen was directly delivered to the stream, and this finding highlights the importance of quick flow pathways during snowmelt events. These findings indicate that interactions among sources, transformations, and hydrologic transport processes must be deciphered to understand why concentrations vary over time and over space as well as to elucidate the direct effects of human activities on nutrient dynamics in upland forest streams.

Production of single-walled carbon nanotube grids

DOEpatents

Hauge, Robert H; Xu, Ya-Qiong; Pheasant, Sean

2013-12-03

A method of forming a nanotube grid includes placing a plurality of catalyst nanoparticles on a grid framework, contacting the catalyst nanoparticles with a gas mixture that includes hydrogen and a carbon source in a reaction chamber, forming an activated gas from the gas mixture, heating the grid framework and activated gas, and controlling a growth time to generate a single-wall carbon nanotube array radially about the grid framework. A filter membrane may be produced by this method.

Attention improves memory by suppressing spiking-neuron activity in the human anterior temporal lobe.

PubMed

Wittig, John H; Jang, Anthony I; Cocjin, John B; Inati, Sara K; Zaghloul, Kareem A

2018-06-01

We identify a memory-specific attention mechanism in the human anterior temporal lobe, an area implicated in semantic processing and episodic memory formation. Spiking neuron activity is suppressed and becomes more reliable in preparation for verbal memory formation. Intracranial electroencephalography signals implicate this region as a source of executive control for attentional selection. Consistent with this interpretation, its surgical removal causes significant memory impairment for attended words relative to unattended words.

Pouteria torta epicarp as a useful source of α-amylase inhibitor in the control of type 2 diabetes.

PubMed

de Sales, Paloma Michelle; de Souza, Paula Monteiro; Dartora, Mariana; Resck, Inês Sabioni; Simeoni, Luiz Alberto; Fonseca-Bazzo, Yris Maria; de Oliveira Magalhães, Pérola; Silveira, Dâmaris

2017-11-01

Type 2 diabetes plays a major role in public health, affecting about 400 million adults. One of the used strategies to control type 2 diabetes is the inhibition of α-amylase activity to reduce post-prandial blood glucose levels. Therefore, in past decades, the search of new α-amylase inhibitors has led to the evaluation of natural products as a source of these compounds. Pouteria torta (Sapotaceae) is widespread in Brazil and bears edible fruits. Epicarp and pulp crude extracts of fresh fruits were studied for in vitro α-amylase inhibition activity. The pulp did not present activity while epicarp, usually considered as waste, showed a high α-amylase inhibitory capacity when compared with acarbose and Triticum aestivum. Therefore, an assay-guided fractionation study of epicarp crude extract was performed. Fraction VI shows very high inhibitory activity with IC 50 of 9 μg/mL. However, subsequent fractionation led to lower inhibition potential (IC 50 of 22.1 μg/mL). The qualitative characterization of fraction VI were performed by chromatographic and spectrometric analysis and showed the presence of epicatechin, catechin, sucrose, glucose, and fructose. Total phenolic and flavonoid contents and antioxidant capacity were also assessed and there seemed to be no correlation between phenolic or flavonoids-rich fractions and antioxidant capacity or α-amylase inhibitory activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evidence of Jovian active longitude: 3. Observational constraints

NASA Astrophysics Data System (ADS)

Galopeau, P. H. M.; Boudjada, M. Y.

2010-12-01

The occurrence probability of the Io-controlled Jovian decameter radio emissions depends on the central meridian longitude and the orbital phase of the satellite Io. Investigations by Galopeau et al. (2004, 2007) have shown that some specific Jovian "active" longitudes favor the radiation. The authors proposed a model which involves the cyclotron maser instability (CMI) as the mechanism at the origin of the Jovian radio emissions produced near the local gyrofrequency, along an active magnetic field line carried away by Io through its revolution around Jupiter. Those studies brought out the existence of an active longitude anchored in Jupiter's magnetic field and directly related to the efficiency of the CMI. In the present analysis, we model the four occurrence regions associated to Io-controlled sources. This approach is in a reverse way of the parametric method developed by Galopeau et al. (2007). The properties of the propagation and polarization of the radio wave, derived from the CMI, are the key ingredients for the study of the beaming cone. It is shown that the lead angle of the active magnetic field line relative to Io has a significant effect on both the selection of the propagation conditions and the limit between the right- and left-hand polarization states. The modeled and observed occurrence regions are found to be similar for a lead angle of about 20°. However, it seems that the behaviors of the southern and northern sources are not alike despite a common generation mechanism.

Potentiated processing of negative feedback in depression is attenuated by anhedonia

PubMed Central

Mueller, E. M.; Pechtel, P.; Cohen, A.L.; Douglas, S.R.; Pizzagalli, D.A.

2014-01-01

Background Although cognitive theories of depression have postulated enhanced processing of negatively valenced information, previous EEG studies have shown both increased and reduced sensitivity for negative performance feedback in MDD. To reconcile these paradoxical findings, it has been speculated that sensitivity for negative feedback is potentiated in moderate MDD but reduced in highly anhedonic subjects. The goal of this study was to test this hypothesis by analyzing the feedback-related negativity (FRN), frontomedial theta power (FMT), and source-localized anterior midcingulate cortex (aMCC) activity after negative feedback. Methods Fourteen unmedicated participants with MDD and 15 control participants performed a reinforcement learning task while 128-channel EEG was recorded. FRN, FMT and LORETA source-localized aMCC activity after negative and positive feedback were compared between groups. Results The MDD group showed higher FRN amplitudes and aMCC activation to negative feedback than controls. Moreover, aMCC activation to negative feedback was inversely related to self-reported anhedonia. In contrast, self-reported anxiety correlated with feedback-evoked frontomedial theta (FMT) within the depression group. Conclusions The present findings suggest that, among depressed and anxious individuals, enhanced processing of negative feedback occurs relatively early in the information processing stream. These results extend prior work and indicate that although moderate depression is associated with elevated sensitivity for negative feedback, high levels of anhedonia may attenuate this effect. PMID:25620272

A Nitrogen Response Pathway Regulates Virulence Functions in Fusarium oxysporum via the Protein Kinase TOR and the bZIP Protein MeaB[C][W

PubMed Central

López-Berges, Manuel S.; Rispail, Nicolas; Prados-Rosales, Rafael C.; Di Pietro, Antonio

2010-01-01

During infection, fungal pathogens activate virulence mechanisms, such as host adhesion, penetration and invasive growth. In the vascular wilt fungus Fusarium oxysporum, the mitogen-activated protein kinase Fmk1 is required for plant infection and controls processes such as cellophane penetration, vegetative hyphal fusion, or root adhesion. Here, we show that these virulence-related functions are repressed by the preferred nitrogen source ammonium and restored by treatment with l-methionine sulfoximine or rapamycin, two specific inhibitors of Gln synthetase and the protein kinase TOR, respectively. Deletion of the bZIP protein MeaB also resulted in nitrogen source–independent activation of virulence mechanisms. Activation of these functions did not require the global nitrogen regulator AreA, suggesting that MeaB-mediated repression of virulence functions does not act through inhibition of AreA. Tomato plants (Solanum lycopersicum) supplied with ammonium rather than nitrate showed a significant reduction in vascular wilt symptoms when infected with the wild type but not with the ΔmeaB strain. Nitrogen source also affected invasive growth in the rice blast fungus Magnaporthe oryzae and the wheat head blight pathogen Fusarium graminearum. We propose that a conserved nitrogen-responsive pathway might operate via TOR and MeaB to control virulence in plant pathogenic fungi. PMID:20639450

Membrane stabilization activity as anti-inflammatory mechanisms of Vernonia amygdalina leaves extracts

NASA Astrophysics Data System (ADS)

Nuryanto, MK; Paramita, S.; Iskandar, A.

2018-04-01

Inflammation is a normal process in the human body as a response to injury from healing process. Meanwhile, chronic inflammation will cause new health problems to patients. Anti-inflammatory agents generally used for those conditions, have several side effects to patients. The aim of this research was to find alternative anti-inflammatory agents, especially from natural sources. Vernonia amygdalina knew locally as “daun afrika” belong to family Apiaceae is one of those potential natural sources for alternative anti-inflammatory agents. This plant is known astraditionalmedicine from East Kalimantanfor health problems caused by the muscle stiffness and used as material in this research. The experimental method of anti-inflammatory measurement using membrane stabilization activity for V. amygdalina leaves extracts. The results showed that significant differences of EC50(p<0.05)achieved between indomethacin as the positive control (26.39 ± 2.91 µg/mL) with V. amygdalina leaves extracts for concentration 1% (131.81 ± 2.95 µg/mL) and 10% (62.54 ± 2.05 µg/mL). EC50 of V.amygdalina leaves extracts showed the potential anti-inflammatory activities. It could be concluded that V. amygdalina leaves extracts to have anti-inflammatory activities, which could be further developed as a new natural source of the anti-inflammatory agents.

Do Increases in Patient Activation Result in Improved Self-Management Behaviors?

PubMed Central

Hibbard, Judith H; Mahoney, Eldon R; Stock, Ronald; Tusler, Martin

2007-01-01

Objective The purpose of this study is to determine whether patient activation is a changing or changeable characteristic and to assess whether changes in activation also are accompanied by changes in health behavior. Study Methods To obtain variability in activation and self-management behavior, a controlled trial with chronic disease patients randomized into either intervention or control conditions was employed. In addition, changes in activation that occurred in the total sample were also examined for the study period. Using Mplus growth models, activation latent growth classes were identified and used in the analysis to predict changes in health behaviors and health outcomes. Data Sources Survey data from the 479 participants were collected at baseline, 6 weeks, and 6 months. Principal Findings Positive change in activation is related to positive change in a variety of self-management behaviors. This is true even when the behavior in question is not being performed at baseline. When the behavior is already being performed at baseline, an increase in activation is related to maintaining a relatively high level of the behavior over time. The impact of the intervention, however, was less clear, as the increase in activation in the intervention group was matched by nearly equal increases in the control group. Conclusions Results suggest that if activation is increased, a variety of improved behaviors will follow. The question still remains, however, as to what interventions will improve activation. PMID:17610432

10 CFR 835.1201 - Sealed radioactive source control.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled, and...

10 CFR 835.1201 - Sealed radioactive source control.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 4 2011-01-01 2011-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled, and...

10 CFR 835.1201 - Sealed radioactive source control.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 4 2013-01-01 2013-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled, and...

10 CFR 835.1201 - Sealed radioactive source control.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 4 2014-01-01 2014-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled, and...

10 CFR 835.1201 - Sealed radioactive source control.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 4 2012-01-01 2012-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled, and...

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

Stavrov, Andrei; Yamamoto, Eugene

Radiation Portal Monitors (RPM) with plastic detectors represent the main instruments used for primary border (customs) radiation control. RPM are widely used because they are simple, reliable, relatively inexpensive and have a high sensitivity. However, experience using the RPM in various countries has revealed the systems have some grave shortcomings. There is a dramatic decrease of the probability of detection of radioactive sources under high suppression of the natural gamma background (radiation control of heavy cargoes, containers and, especially, trains). NORM (Naturally Occurring Radioactive Material) existing in objects under control trigger the so-called 'nuisance alarms', requiring a secondary inspection formore » source verification. At a number of sites, the rate of such alarms is so high it significantly complicates the work of customs and border officers. This paper presents a brief description of new variant of algorithm ASIA-New (New Advanced Source Identification Algorithm), which was developed by the Rapiscan company. It also demonstrates results of different tests and the capability of a new system to overcome the shortcomings stated above. New electronics and ASIA-New enables RPM to detect radioactive sources under a high background suppression (tested at 15-30%) and to verify the detected NORM (KCl) and the artificial isotopes (Co- 57, Ba-133 and other). New variant of ASIA is based on physical principles, a phenomenological approach and analysis of some important parameter changes during the vehicle passage through the monitor control area. Thanks to this capability main advantage of new system is that this system can be easily installed into any RPM with plastic detectors. Taking into account that more than 4000 RPM has been installed worldwide their upgrading by ASIA-New may significantly increase probability of detection and verification of radioactive sources even masked by NORM. This algorithm was tested for 1,395 passages of different transports (cars, trucks and trailers) without radioactive sources. It also was tested for 4,015 passages of these transports with radioactive sources of different activity (Co-57, Ba-133, Cs-137, Co-60, Ra-226, Th-232) and these sources masked by NORM (K-40) as well. (authors)« less

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.

Effects of UPR and ERAD pathway on the prolyl endopeptidase production in Pichia pastoris by controlling of nitrogen source.

PubMed

Wang, Xiao-Dong; Jiang, Ting; Yu, Xiao-Wei; Xu, Yan

2017-07-01

Prolyl endopeptidase (PEP) is very useful in various industries, while the high cost of enzyme production remains a major obstacle for its industrial applications. Pichia pastoris has been used for the PEP production; however, the fermentation process has not be investigated and little is known about the impact of excessive PEP production on the host cell physiology. Here, we optimized the nitrogen source to improve the PEP expression level and further evaluated the cellular response including UPR and ERAD. During methanol induction phase the PEP activity (1583 U/L) was increased by 1.48-fold under the optimized nitrogen concentration of NH 4 + (300 mmol/L) and casamino acids [1.0% (w/v)] in a 3-L bioreactor. Evaluated by RT-PCR the UPR and ERAD pathways were confirmed to be activated. Furthermore, a strong decrease of ERAD-related gene transcription was observed with the addition of nitrogen source, which contributed to a higher PEP expression level.

Interactions of oversulfated chondroitin sulfate (OSCS) from different sources with unfractionated heparin.

PubMed

Gray, Angel; Litinas, Evangelos; Jeske, Walter; Fareed, Jawed; Hoppensteadt, Debra

2012-01-01

In 2008, oversulfated chondroitin sulfate (OSCS) was identified as the main contaminant in recalled heparin. Oversulfated chondroitin sulfate can be prepared from bovine (B), porcine (P), shark (Sh), or skate (S) origin and may produce changes in the antithrombotic, bleeding, and hemodynamic profile of heparins. This study examines the interactions of various OSCSs on heparin in animal models of thrombosis and bleeding, as well as on the anticoagulant and antiprotease effects in in vitro assays. Mixtures of 70% unfractionated heparin (UFH) with 30% OSCS from different sources were tested. In the in vitro activated partial thromboplastin time (aPTT) assay, all contaminant mixtures showed a decrease in clotting times. In addition, a significant increase in bleeding time compared to the control (UFH/saline) was observed. In the thrombosis model, no significant differences were observed. The OSCSs significantly increased anti-Xa activity in ex vivo blood samples. These results indicate that various sources of OSCS affect the hemostatic properties of heparin.

An analysis of job placement patterns of black and non-black male and female undergraduates at the University of Virginia and Hampton Institute. Ph.D. Thesis - Virginia Univ.

NASA Technical Reports Server (NTRS)

Anderson, A. F.

1974-01-01

Research questions were proposed to determine the relationship between independent variables (race, sex, and institution attended) and dependent variables (number of job offers received, salary received, and willingness to recommend source of employer contact). The control variables were academic major, grade point average, placement registration, nonemployment activity, employer, and source of employer contact. An analysis of the results revealed no statistical significance of the institution attended as a predictor of job offers or salary, although significant relationships were found between race and sex and number of job offers received. It was found that academic major, grade point average, and source of employer contact were more useful than race in the prediction of salary. Sex and nonemployment activity were found to be the most important variables in the model. The analysis also indicated that Black students received more job offers than non-Black students.

Seal Investigations of an Active Clearance Control System Concept

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.; Taylor, Shawn; Oswald, Jay; DeCastro, Jonathan A.

2006-01-01

In an effort to improve upon current thermal active clearance control methods, a first generation, fast-acting mechanically actuated, active clearance control system has been designed and installed into a non-rotating test rig. In order to harvest the benefit of tighter blade tip clearances, low-leakage seals are required for the actuated carrier segments of the seal shroud to prevent excessive leakage of compressor discharge (P3) cooling air. The test rig was designed and fabricated to facilitate the evaluation of these types of seals, identify seal leakage sources, and test other active clearance control system concepts. The objective of this paper is to present both experimental and analytical investigations into the nature of the face-seal to seal-carrier interface. Finite element analyses were used to examine face seal contact pressures and edge-loading under multiple loading conditions, varied E-seal positions and two new face seal heights. The analyses indicated that moving the E-seal inward radially and reducing face seal height would lead to more uniform contact conditions between the face seal and the carriers. Lab testing confirmed that moving the balance diameter inward radially caused a decrease in overall system leakage.

The use of current source density as electrophysiological correlates in neuropsychiatric disorders: a review of human studies

PubMed Central

Kamarajan, Chella; Pandey, Ashwini K.; Chorlian, David B.; Porjesz, Bernice

2014-01-01

The use of current source density (CSD), the Laplacian of the scalp surface voltage, to map the electrical activity of the brain is a powerful method in studies of cognitive and affective phenomena. During the last few decades, mapping of CSD has been successfully applied to characterize several neuropsychiatric conditions such as alcoholism, schizophrenia, depression, anxiety disorders, childhood/developmental disorders, and neurological conditions (i.e., epilepsy and brain lesions) using electrophysiological data from resting state and during cognitive performance. Use of CSD and Laplacian measures has proven effective in elucidating topographic and activation differences between groups: i) patients with a specific diagnosis vs. healthy controls, ii) subjects at high risk for a specific diagnosis vs. low risk or normal controls, and iii) patients with specific symptom(s) vs. patients without these symptom(s). The present review outlines and summarizes the studies that have employed CSD measures in investigating several neuropsychiatric conditions. The advantages and potential of CSD-based methods in clinical and research applications along with some of the limitations inherent in the CSD-based methods are discussed in the review, as well as future directions to expand the implementation of CSD to other potential clinical applications. As CSD methods have proved to be more advantageous than using scalp potential data to understand topographic and source activations, its clinical applications offer promising potential, not only for a better understanding of a range of psychiatric conditions, but also for a variety of focal neurological disorders, including epilepsy and other conditions involving brain lesions and surgical interventions. PMID:25448264

40 CFR 60.4905 - What are the monitoring and calibration requirements for compliance with my operating limits?

Code of Federal Regulations, 2014 CFR

2014-07-01

... malfunctions, or required monitoring system quality assurance or control activities conducted during monitoring... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What are the monitoring and calibration... SOURCES Standards of Performance for New Sewage Sludge Incineration Units Performance Testing, Monitoring...

40 CFR 60.4905 - What are the monitoring and calibration requirements for compliance with my operating limits?

Code of Federal Regulations, 2011 CFR

2011-07-01

... malfunctions, or required monitoring system quality assurance or control activities conducted during monitoring... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What are the monitoring and calibration... SOURCES Standards of Performance for New Sewage Sludge Incineration Units Performance Testing, Monitoring...

40 CFR 60.4905 - What are the monitoring and calibration requirements for compliance with my operating limits?

Code of Federal Regulations, 2012 CFR

2012-07-01

... malfunctions, or required monitoring system quality assurance or control activities conducted during monitoring... 40 Protection of Environment 7 2012-07-01 2012-07-01 false What are the monitoring and calibration... SOURCES Standards of Performance for New Sewage Sludge Incineration Units Performance Testing, Monitoring...

40 CFR 60.4905 - What are the monitoring and calibration requirements for compliance with my operating limits?

Code of Federal Regulations, 2013 CFR

2013-07-01

... malfunctions, or required monitoring system quality assurance or control activities conducted during monitoring... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What are the monitoring and calibration... SOURCES Standards of Performance for New Sewage Sludge Incineration Units Performance Testing, Monitoring...

Independent Oscillatory Patterns Determine Performance Fluctuations in Children with Attention Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

Yordanova, Juliana; Albrecht, Bjorn; Uebel, Henrik; Kirov, Roumen; Banaschewski, Tobias; Rothenberger, Aribert; Kolev, Vasil

2011-01-01

The maintenance of stable goal-directed behaviour is a hallmark of conscious executive control in humans. Notably, both correct and error human actions may have a subconscious activation-based determination. One possible source of subconscious interference may be the default mode network that, in contrast to attentional network, manifests…

THE DISTRIBUTION OF CHLORPYRIFOS FOLLOWING A CRACK AND CREVICE TYPE APPLICAITON IN THE U.S. EPA INDOOR AIR QUALITY (IAQ) TEST HOUSE

EPA Science Inventory

Pesticides found in homes may result from indoor applications to control household pests or by translocation from outdoor sources. Pesticides disperse according to their physical properties and other factors such as human activity, residential air exchange, temperature and humi...

Sources of Strength: Women and Culture. A Teacher's Guide.

ERIC Educational Resources Information Center

Hunter, Lisa K.; And Others

The document presents teaching methods, content, and learning activities for units in multicultural women's studies for secondary students. The major objective is to help students answer the question, "How much control can a person exercise over her/his own life?" Students learn about the ways women have lived their lives and perceived…

Application of Preventative Legal Considerations to the Alumni Affairs Administrator.

ERIC Educational Resources Information Center

Miles, Albert S.; Miller, Michael T.

Colleges and universities increasingly rely on fund raising activities as a major source of operating revenue, a process which is wrought with legal pitfalls. This document provides an overview of the legal considerations of fund raising for the alumni and development officer, focusing particularly on span of control considerations between alumni…

THE SPATIAL AND TEMPORAL DISTRIBUTION OF CHLORPYRIFOS IN THE U.S. EPA INDOOR AIR QUALITY (IAQ) TEST HOUSE FOLLOWING CRACK AND CREVICE TYPE APPLICATIONS

EPA Science Inventory

Pesticides found in homes may result from indoor applications to control household pests or by translocation from outdoor sources. Pesticides disperse according to their physical properties and other factors such as human activity, air exchange, temperature and humidity. Insect...

A wirelessly controlled implantable LED system for deep brain optogenetic stimulation

PubMed Central

Rossi, Mark A.; Go, Vinson; Murphy, Tracy; Fu, Quanhai; Morizio, James; Yin, Henry H.

2015-01-01

In recent years optogenetics has rapidly become an essential technique in neuroscience. Its temporal and spatial specificity, combined with efficacy in manipulating neuronal activity, are especially useful in studying the behavior of awake behaving animals. Conventional optogenetics, however, requires the use of lasers and optic fibers, which can place considerable restrictions on behavior. Here we combined a wirelessly controlled interface and small implantable light-emitting diode (LED) that allows flexible and precise placement of light source to illuminate any brain area. We tested this wireless LED system in vivo, in transgenic mice expressing channelrhodopsin-2 in striatonigral neurons expressing D1-like dopamine receptors. In all mice tested, we were able to elicit movements reliably. The frequency of twitches induced by high power stimulation is proportional to the frequency of stimulation. At lower power, contraversive turning was observed. Moreover, the implanted LED remains effective over 50 days after surgery, demonstrating the long-term stability of the light source. Our results show that the wireless LED system can be used to manipulate neural activity chronically in behaving mice without impeding natural movements. PMID:25713516

Selective neural activation in a histologically derived model of peripheral nerve

NASA Astrophysics Data System (ADS)

Butson, Christopher R.; Miller, Ian O.; Normann, Richard A.; Clark, Gregory A.

2011-06-01

Functional electrical stimulation (FES) is a general term for therapeutic methods that use electrical stimulation to aid or replace lost ability. For FES systems that communicate with the nervous system, one critical component is the electrode interface through which the machine-body information transfer must occur. In this paper, we examine the influence of inhomogeneous tissue conductivities and positions of nodes of Ranvier on activation of myelinated axons for neuromuscular control as a function of electrode configuration. To evaluate these effects, we developed a high-resolution bioelectric model of a fascicle from a stained cross-section of cat sciatic nerve. The model was constructed by digitizing a fixed specimen of peripheral nerve, extruding the image along the axis of the nerve, and assigning each anatomical component to one of several different tissue types. Electrodes were represented by current sources in monopolar, transverse bipolar, and longitudinal bipolar configurations; neural activation was determined using coupled field-neuron simulations with myelinated axon cable models. We found that the use of an isotropic tissue medium overestimated neural activation thresholds compared with the use of physiologically based, inhomogeneous tissue medium, even after controlling for mean impedance levels. Additionally, the positions of the cathodic sources relative to the nodes of Ranvier had substantial effects on activation, and these effects were modulated by the electrode configuration. Our results indicate that physiologically based tissue properties cause considerable variability in the neural response, and the inclusion of these properties is an important component in accurately predicting activation. The results are used to suggest new electrode designs to enable selective stimulation of small diameter fibers.

A second chance: meanings of body weight, diet, and physical activity to women who have experienced cancer.

PubMed

Maley, Mary; Warren, Barbour S; Devine, Carol M

2013-01-01

To understand the meanings of diet, physical activity, and body weight in the context of women's cancer experiences. Grounded theory using 15 qualitative interviews and 3 focus groups. Grassroots community cancer organizations in the northeastern United States. Thirty-six white women cancer survivors; 86% had experienced breast cancer. Participants' views of the meanings of body weight, diet, and physical activity in the context of the cancer. Procedures adapted from the constant comparative method of qualitative analysis using iterative open coding. Themes emerged along 3 intersecting dimensions: vulnerability and control, stress and living well, and uncertainty and confidence. Diet and body weight were seen as sources of increased vulnerability and distress. Uncertainty about diet heightened distress and lack of control. Physical activity was seen as a way to regain control and reduce distress. Emergent themes of vulnerability-control, stress-living well, and uncertainty-confidence may aid in understanding and promoting health behaviors in the growing population of cancer survivors. Messages that resonated with participants included taking ownership over one's body, physical activity as stress reduction, healthy eating for overall health and quality of life, and a second chance to get it right. Copyright © 2013 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Shape memory alloy actuated adaptive exhaust nozzle for jet engine

NASA Technical Reports Server (NTRS)

Ma, Ning (Inventor); Song, Gangbing (Inventor)

2009-01-01

The proposed adaptive exhaust nozzle features an innovative use of the shape memory alloy (SMA) actuators for actively control of the opening area of the exhaust nozzle for jet engines. The SMA actuators remotely control the opening area of the exhaust nozzle through a set of mechanism. An important advantage of using SMA actuators is the reduction of weight of the actuator system for variable area exhaust nozzle. Another advantage is that the SMA actuator can be activated using the heat from the exhaust and eliminate the need of other energy source. A prototype has been designed and fabricated. The functionality of the proposed SMA actuated adaptive exhaust nozzle is verified in the open-loop tests.

Modelling of piezoelectric actuator dynamics for active structural control

NASA Technical Reports Server (NTRS)

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

1990-01-01

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

Converter topologies and control

DOEpatents

Rodriguez, Fernando; Qin, Hengsi; Chapman, Patrick

2018-05-01

An inverter includes a transformer that includes a first winding, a second winding, and a third winding, a DC-AC inverter electrically coupled to the first winding of the transformer, a cycloconverter electrically coupled to the second winding of the transformer, an active filter electrically coupled to the third winding of the transformer. The DC-AC inverter is adapted to convert the input DC waveform to an AC waveform delivered to the transformer at the first winding. The cycloconverter is adapted to convert an AC waveform received at the second winding of the transformer to the output AC waveform having a grid frequency of the AC grid. The active filter is adapted to sink and source power with one or more energy storage devices based on a mismatch in power between the DC source and the AC grid.

Metabolic control of the epigenome in systemic Lupus erythematosus

PubMed Central

Oaks, Zachary; Perl, Andras

2014-01-01

Epigenetic mechanisms are proposed to underlie aberrant gene expression in systemic lupus erythematosus (SLE) that results in dysregulation of the immune system and loss of tolerance. Modifications of DNA and histones require substrates derived from diet and intermediary metabolism. DNA and histone methyltransferases depend on S-adenosylmethionine (SAM) as a methyl donor. SAM is generated from adenosine triphosphate (ATP) and methionine by methionine adenosyltransferase (MAT), a redox-sensitive enzyme in the SAM cycle. The availability of B vitamins and methionine regulate SAM generation. The DNA of SLE patients is hypomethylated, indicating dysfunction in the SAM cycle and methyltransferase activity. Acetyl-CoA, which is necessary for histone acetylation, is generated from citrate produced in mitochondria. Mitochondria are also responsible for de novo synthesis of flavin adenine dinucleotide (FAD) for histone demethylation. Mitochondrial oxidative phosphorylation is the dominant source of ATP. The depletion of ATP in lupus T cells may affect MAT activity as well as adenosine monophosphate (AMP) activated protein kinase (AMPK), which phosphorylates histones and inhibits mechanistic target of rapamycin (mTOR). In turn, mTOR can modify epigenetic pathways including methylation, demethylation, and histone phosphorylation and mediates enhanced T-cell activation in SLE. Beyond their role in metabolism, mitochondria are the main source of reactive oxygen intermediates (ROI), which activate mTOR and regulate the activity of histone and DNA modifying enzymes. In this review we will focus on the sources of metabolites required for epigenetic regulation and how the flux of the underlying metabolic pathways affects gene expression. PMID:24128087

Participatory health impact assessment for the development of local government regulation on hazard control

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

Inmuong, Uraiwan, E-mail: uraiwan@kku.ac.t; Faculty of Public Health, Khon Kaen University, Thailand 123 Mittrapharb Road, Khon Kaen 40002; Rithmak, Panee, E-mail: panrit@kku.ac.t

The Thai Public Health Act 1992 required the Thai local governments to issue respective regulations to take control of any possible health-hazard related activities, both from commercial and noncommercial sources. Since 1999, there has been centrally decentralized of power to a new form of local government establishment, namely Sub-district Administrative Organization (SAO). The SAO is asmall-scale local governing structure while its legitimate function is for community services, including control of health impact related activities. Most elected SAO administrators and officers are new and less experience with any of public health code of practice, particularly on health-hazard control. This action researchmore » attempted to introduce and apply a participatory health impact assessment (HIA) tool for the development of SAO health-hazard control regulation. The study sites were at Ban Meang and Kok See SAOs, Khon Kaen Province, Thailand, while all intervention activities conducted during May 2005-April 2006. A set of cooperative activities between researchers and community representatives were planned and organized by; surveying and identifying place and service base locally causing local environmental health problems, organizing community participatory workshops for drafting and proposing the health-hazard control regulation, and appropriate practices for health-hazard controlling measures. This action research eventually could successfully enable the SAO administrators and officers understanding of local environmental-related health problem, as well as development of imposed health-hazard control regulation for local community.« less

Impact of Source Control in Patients With Severe Sepsis and Septic Shock.

PubMed

Martínez, María Luisa; Ferrer, Ricard; Torrents, Eva; Guillamat-Prats, Raquel; Gomà, Gemma; Suárez, David; Álvarez-Rocha, Luis; Pozo Laderas, Juan Carlos; Martín-Loeches, Ignacio; Levy, Mitchell M; Artigas, Antonio

2017-01-01

Time to clearance of pathogens is probably critical to outcome in septic shock. Current guidelines recommend intervention for source control within 12 hours after diagnosis. We aimed to determine the epidemiology of source control in the management of sepsis and to analyze the impact of timing to source control on mortality. Prospective observational analysis of the Antibiotic Intervention in Severe Sepsis study, a Spanish national multicenter educational intervention to improve antibiotherapy in sepsis. Ninety-nine medical-surgical ICUs in Spain. We enrolled 3,663 patients with severe sepsis or septic shock during three 4-month periods between 2011 and 2013. Source control and hospital mortality. A total of 1,173 patients (32%) underwent source control, predominantly for abdominal, urinary, and soft-tissue infections. Compared with patients who did not require source control, patients who underwent source control were older, with a greater prevalence of shock, major organ dysfunction, bacteremia, inflammatory markers, and lactic acidemia. In addition, compliance with the resuscitation bundle was worse in those undergoing source control. In patients who underwent source control, crude ICU mortality was lower (21.2% vs 25.1%; p = 0.010); after adjustment for confounding factors, hospital mortality was also lower (odds ratio, 0.809 [95% CI, 0.658-0.994]; p = 0.044). In this observational database analysis, source control after 12 hours was not associated with higher mortality (27.6% vs 26.8%; p = 0.789). Despite greater severity and worse compliance with resuscitation bundles, mortality was lower in septic patients who underwent source control than in those who did not. The time to source control could not be linked to survival in this observational database.

Modeling and analysis of secondary sources coupling for active sound field reduction in confined spaces

NASA Astrophysics Data System (ADS)

Montazeri, Allahyar; Taylor, C. James

2017-10-01

This article addresses the coupling of acoustic secondary sources in a confined space in a sound field reduction framework. By considering the coupling of sources in a rectangular enclosure, the set of coupled equations governing its acoustical behavior are solved. The model obtained in this way is used to analyze the behavior of multi-input multi-output (MIMO) active sound field control (ASC) systems, where the coupling of sources cannot be neglected. In particular, the article develops the analytical results to analyze the effect of coupling of an array of secondary sources on the sound pressure levels inside an enclosure, when an array of microphones is used to capture the acoustic characteristics of the enclosure. The results are supported by extensive numerical simulations showing how coupling of loudspeakers through acoustic modes of the enclosure will change the strength and hence the driving voltage signal applied to the secondary loudspeakers. The practical significance of this model is to provide a better insight on the performance of the sound reproduction/reduction systems in confined spaces when an array of loudspeakers and microphones are placed in a fraction of wavelength of the excitation signal to reduce/reproduce the sound field. This is of particular importance because the interaction of different sources affects their radiation impedance depending on the electromechanical properties of the loudspeakers.

Nitrogen transport within an agricultural landscape: insights on how hydrology, biogeochemistry, and the landscape intersect to control the fate and transport of nitrogen in the Mississippi Delta

USGS Publications Warehouse

Barlow, Jeannie R.; Kröger, Robert

2014-01-01

Nitrogen (N) is a ubiquitous contaminant throughout agricultural landscapes due to both the application of inorganic and organic fertilizers to agricultural fields and the general persistence of nitrate (NO3 ) in oxygenated aqueous environments (Denver et al. 2010; Domagalski et al. 2008; Green et al. 2008; Coupe 2001; Nolan and Stoner 2000). In order to understand why excess N occurs various hydrologic systems (environments), it is important to consider potential sources, the locations of these sources in the watershed, and the timing of the application of sources with respect to the movement of water. To learn how to manage N in a watershed, it is necessary to identify and quantify flow paths and biogeochemical conditions, which ultimately combine to determine transport and fate. If sources, transport mechanisms, and biogeochemical controls were uniformly distributed, it would be possible to manage N uniformly throughout a watershed. However, uniform conditions are rare to nonexistent in the natural world and in the landscape altered for agricultural production. In order to adjust management activities on the landscape to have the greatest effect, it is important to understand the fate and transport N within the intersection of hydrology and biogeochemistry, that is, to understand the extent and duration of the hydrologic and biogeochemical controls as N is routed through and among each hydrologic compartment.

Complement factor H protects mice from ischemic acute kidney injury but is not critical for controlling complement activation by glomerular IgM.

PubMed

Goetz, Lindsey; Laskowski, Jennifer; Renner, Brandon; Pickering, Matthew C; Kulik, Liudmila; Klawitter, Jelena; Stites, Erik; Christians, Uwe; van der Vlag, Johan; Ravichandran, Kameswaran; Holers, V Michael; Thurman, Joshua M

2018-05-01

Natural IgM binds to glomerular epitopes in several progressive kidney diseases. Previous work has shown that IgM also binds within the glomerulus after ischemia/reperfusion (I/R) but does not fully activate the complement system. Factor H is a circulating complement regulatory protein, and congenital or acquired deficiency of factor H is a strong risk factor for several types of kidney disease. We hypothesized that factor H controls complement activation by IgM in the kidney after I/R, and that heterozygous factor H deficiency would permit IgM-mediated complement activation and injury at this location. We found that mice with targeted heterozygous deletion of the gene for factor H developed more severe kidney injury after I/R than wild-type controls, as expected, but that complement activation within the glomeruli remained well controlled. Furthermore, mice that are unable to generate soluble IgM were not protected from renal I/R, even in the setting of heterozygous factor H deficiency. These results demonstrate that factor H is important for limiting injury in the kidney after I/R, but it is not critical for controlling complement activation by immunoglobulin within the glomerulus in this setting. IgM binds to glomerular epitopes after I/R, but it is not a significant source of injury. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design of a variable width pulse generator feasible for manual or automatic control

NASA Astrophysics Data System (ADS)

Vegas, I.; Antoranz, P.; Miranda, J. M.; Franco, F. J.

2017-01-01

A variable width pulse generator featuring more than 4-V peak amplitude and less than 10-ns FWHM is described. In this design the width of the pulses is controlled by means of the control signal slope. Thus, a variable transition time control circuit (TTCC) is also developed, based on the charge and discharge of a capacitor by means of two tunable current sources. Additionally, it is possible to activate/deactivate the pulses when required, therefore allowing the creation of any desired pulse pattern. Furthermore, the implementation presented here can be electronically controlled. In conclusion, due to its versatility, compactness and low cost it can be used in a wide variety of applications.

Charting a Path to Location Intelligence for STD Control.

PubMed

Gerber, Todd M; Du, Ping; Armstrong-Brown, Janelle; McNutt, Louise-Anne; Coles, F Bruce

2009-01-01

This article describes the New York State Department of Health's GeoDatabase project, which developed new methods and techniques for designing and building a geocoding and mapping data repository for sexually transmitted disease (STD) control. The GeoDatabase development was supported through the Centers for Disease Control and Prevention's Outcome Assessment through Systems of Integrated Surveillance workgroup. The design and operation of the GeoDatabase relied upon commercial-off-the-shelf tools that other public health programs may also use for disease-control systems. This article provides a blueprint of the structure and software used to build the GeoDatabase and integrate location data from multiple data sources into the everyday activities of STD control programs.

[Three types of self-esteem: its characteristic differences of contingency and contentment of sources of self-esteem].

PubMed

Ito, Masaya; Kawasaki, Naoki; Kodama, Masahiro

2011-02-01

Previous research and theory (Crocker & Wolfe, 2001; Kernis, 2003) suggests that adaptive self-esteem stems from just being oneself, and is characterized by a sense of authenticity (SOA). Maladaptive self-esteem is derived from meeting external standards and social comparisons, and is characterized by a sense of superiority (SOS). Thus, the qualitative difference between SOA and SOS depends on the sources of self-esteem. We hypothesized that SOA is related to internal sources of self-esteem, while SOS is related to external sources. In order to control for covariance, global self-esteem was also examined in a questionnaire survey of self-esteem that was administered to 273 university students. The results of a partial correlation analysis showed that SOA was positively correlated with internal sources of self-esteem such as committed activities and efforts for self-development. In contrast, SOS was positively correlated with external sources of self-esteem such as approval from others and appearance. These results mainly support our hypotheses.

Comparison of the air pollution biomonitoring ability of three Tillandsia species and the lichen Ramalina celastri in Argentina.

PubMed

Bermudez, Gonzalo M A; Rodriguez, Judith H; Pignata, María L

2009-01-01

Bioaccumulation ability and response to air pollution sources were evaluated for Tillandsia capillaris Ruíz and Pav. f. capillaris, T. recurvata L., T. tricholepis Baker and the lichen Ramalina celastri (Spreng.) Krog. and Swinsc. Epiphyte samples collected from a non contaminated area in the province of Córdoba were transplanted to a control site and three areas categorised according to agricultural, urban and industrial (metallurgical and metal-mechanical) emission sources. Bioindicators were exposed for 3-, 6- and 9-month periods. A foliar damage index was established for Tillandsia and a pollution index for the lichen, and S, Fe, Mn and Zn concentrations were determined. An order of efficiency for the species and conditions studied is proposed taking into account heavy metal accumulation: T. recurvata >T. tricholepis >R. celastri >T. capillaris. All species studied showed Mn to be related to agricultural activity and Fe to industries and soil particles, and Zn was related to urban and industrial sources. As far as physiological response is concerned, T. tricholepis and T. capillaris were more sensitive to agricultural activities, whereas T. recurvata was sensitive to urban and industrial sources, and only partially to agricultural sources. No relationship was found for R. celastri.

MultiElec: A MATLAB Based Application for MEA Data Analysis.

PubMed

Georgiadis, Vassilis; Stephanou, Anastasis; Townsend, Paul A; Jackson, Thomas R

2015-01-01

We present MultiElec, an open source MATLAB based application for data analysis of microelectrode array (MEA) recordings. MultiElec displays an extremely user-friendly graphic user interface (GUI) that allows the simultaneous display and analysis of voltage traces for 60 electrodes and includes functions for activation-time determination, the production of activation-time heat maps with activation time and isoline display. Furthermore, local conduction velocities are semi-automatically calculated along with their corresponding vector plots. MultiElec allows ad hoc signal suppression, enabling the user to easily and efficiently handle signal artefacts and for incomplete data sets to be analysed. Voltage traces and heat maps can be simply exported for figure production and presentation. In addition, our platform is able to produce 3D videos of signal progression over all 60 electrodes. Functions are controlled entirely by a single GUI with no need for command line input or any understanding of MATLAB code. MultiElec is open source under the terms of the GNU General Public License as published by the Free Software Foundation, version 3. Both the program and source code are available to download from http://www.cancer.manchester.ac.uk/MultiElec/.

A method for closed-loop presentation of sensory stimuli conditional on the internal brain-state of awake animals

PubMed Central

Rutishauser, Ueli; Kotowicz, Andreas; Laurent, Gilles

2013-01-01

Brain activity often consists of interactions between internal—or on-going—and external—or sensory—activity streams, resulting in complex, distributed patterns of neural activity. Investigation of such interactions could benefit from closed-loop experimental protocols in which one stream can be controlled depending on the state of the other. We describe here methods to present rapid and precisely timed visual stimuli to awake animals, conditional on features of the animal’s on-going brain state; those features are the presence, power and phase of oscillations in local field potentials (LFP). The system can process up to 64 channels in real time. We quantified its performance using simulations, synthetic data and animal experiments (chronic recordings in the dorsal cortex of awake turtles). The delay from detection of an oscillation to the onset of a visual stimulus on an LCD screen was 47.5 ms and visual-stimulus onset could be locked to the phase of ongoing oscillations at any frequency ≤40 Hz. Our software’s architecture is flexible, allowing on-the-fly modifications by experimenters and the addition of new closed-loop control and analysis components through plugins. The source code of our system “StimOMatic” is available freely as open-source. PMID:23473800

Transgenic cotton over-producing spinach sucrose phosphate synthase showed enhanced leaf sucrose synthesis and improved fiber quality under controlled environmental conditions.

PubMed

Haigler, Candace H; Singh, Bir; Zhang, Deshui; Hwang, Sangjoon; Wu, Chunfa; Cai, Wendy X; Hozain, Mohamed; Kang, Wonhee; Kiedaisch, Brett; Strauss, Richard E; Hequet, Eric F; Wyatt, Bobby G; Jividen, Gay M; Holaday, A Scott

2007-04-01

Prior data indicated that enhanced availability of sucrose, a major product of photosynthesis in source leaves and the carbon source for secondary wall cellulose synthesis in fiber sinks, might improve fiber quality under abiotic stress conditions. To test this hypothesis, a family of transgenic cotton plants (Gossypium hirsutum cv. Coker 312 elite) was produced that over-expressed spinach sucrose-phosphate synthase (SPS) because of its role in regulation of sucrose synthesis in photosynthetic and heterotrophic tissues. A family of 12 independent transgenic lines was characterized in terms of foreign gene insertion, expression of spinach SPS, production of spinach SPS protein, and development of enhanced extractable V (max) SPS activity in leaf and fiber. Lines with the highest V (max) SPS activity were further characterized in terms of carbon partitioning and fiber quality compared to wild-type and transgenic null controls. Leaves of transgenic SPS over-expressing lines showed higher sucrose:starch ratio and partitioning of (14)C to sucrose in preference to starch. In two growth chamber experiments with cool nights, ambient CO(2) concentration, and limited light below the canopy, the transgenic line with the highest SPS activity in leaf and fiber had higher fiber micronaire and maturity ratio associated with greater thickness of the cellulosic secondary wall.

Assessment of both environmental cytotoxicity and trace metal pollution using Populus simonii Carr. as a bioindicator.

PubMed

Sluchyk, Victor; Sluchyk, Iryna; Shyichuk, Alexander

2014-10-01

The level of environmental pollution in the city of Ivano-Frankivsk (Western Ukraine) has been assessed by means of roadside poplar trees as bioindicators. Dividable apical meristem cells of rudimentary leaves were quantitatively analysed for mitotic activity and distribution. Anaphases were further examined for chromosomal aberrations. Male catkins were also examined for sterile pollens. Accumulation of trace elements in vegetative buds was also evaluated in order to reveal source(s) of environmental pollution. Poplar trees growing in the urban environment proved to have increased chromosomal aberrations (up to 4-fold) and increased pollen sterility (up to 4-fold) as well as decreased mitotic activity (by factor 1.5) as compared to control sampling site. The biomarker data correlate moderately with increased (up to 4-fold) concentrations of Ni, Zn, Pb, Cd and Cu in vegetative tissues suggesting that probable cause of the environmental cytotoxicity may be vehicle emissions. The maximum increase in chromosomal aberrations (7-fold) and the minimum mitotic activity (half of the control one) were recorded in poplar trees growing in industrial suburb in vicinity of large cement production plant. Taking in mind insignificant bioaccumulation of trace elements in the industrial suburb, the high environmental toxicity has been ascribed to contamination in cement and asbestos particulates.

Low-frequency acoustic pressure, velocity, and intensity thresholds in a bottlenose dolphin (Tursiops truncatus) and white whale (Delphinapterus leucas)

NASA Astrophysics Data System (ADS)

Finneran, James J.; Carder, Donald A.; Ridgway, Sam H.

2002-01-01

The relative contributions of acoustic pressure and particle velocity to the low-frequency, underwater hearing abilities of the bottlenose dolphin (Tursiops truncatus) and white whale (Delphinapterus leucas) were investigated by measuring (masked) hearing thresholds while manipulating the relationship between the pressure and velocity. This was accomplished by varying the distance within the near field of a single underwater sound projector (experiment I) and using two underwater sound projectors and an active sound control system (experiment II). The results of experiment I showed no significant change in pressure thresholds as the distance between the subject and the sound source was changed. In contrast, velocity thresholds tended to increase and intensity thresholds tended to decrease as the source distance decreased. These data suggest that acoustic pressure is a better indicator of threshold, compared to particle velocity or mean active intensity, in the subjects tested. Interpretation of the results of experiment II (the active sound control system) was difficult because of complex acoustic conditions and the unknown effects of the subject on the generated acoustic field; however, these data also tend to support the results of experiment I and suggest that odontocete thresholds should be reported in units of acoustic pressure, rather than intensity.

Direct and inverse modelling for environmental risk assessment and emission control

NASA Astrophysics Data System (ADS)

Penenko, V.; Baklanov, A.; Tsvetova, E.; Mahura, A.

2009-04-01

A concept of environmental modelling and its applications for Siberian regions are presented. The regions are considered both as sources and receptors of pollution as elements of the global climatic system. A methodology has been developed to build the combined methods of forward and inverse modelling for the problems of the air quality, environmental risk assessment and control. It is based on variational principles and methods of adjoint sensitivity theory. This allows obtaining the optimal numerical schemes and universal algorithm of the forward-inverse modelling. Following the concept, the functionals (describing the generalised characteristics of the processes, data, and models) are considered together with the basic model components. To combine all these elements in the frames of forward and inverse relations, we suppose that each of them may contain uncertainty. In this case, it is naturally to formulate a weak-constraint variational principle for the augmented functional which contains the model description in the form of integral identity and the cost functional including the total measure of all uncertainties. The stationary conditions for the augmented functional with respect to the variations its functional arguments define the mutually agreed structure of numerical schemes for forward and adjoint problems, and sensitivity relations. For quantitative risk assessment the following characteristics are useful: (i) values of goal functionals and their variations in a form of sensitivity relations; (ii) risk and sensitivity functions to the variations of the sources. It is convenient to take the risk function multiplied by the source function as a distributed risk measure. The variational technique provides the backward propagation of information, contained in the target functionals, to parameters and sources of the models through the sensitivity and uncertainty functions. This gives a base for realisation of the feedback algorithms and methods of control theory, which are necessary for formulation of multi-criteria optimisation accounting different constraints of ecological, economical, and social essence while solving environmental problems such as air pollution control, placement design for new industrial units, etc. The problems of the long-term environmental forecasting demand revealing the dynamical active zones and the areas of increased sensitivity to the variations of forcings (model parameters). The proposed methodology of accounting the climatic data into environmental studies is suitable for studying such problems. Analysis of the long-term behaviour of the global climatic system and orthogonal decomposition of the multivariate series of meteorological data with respect to the scales of processes allows identifying the activity centers and using this information for construction of scenarios for assessment of risk/vulnerability for sources/receptors. Such analysis for Siberian regions showed that Siberia is situated in areas which separate circulation systems of high energy activity. For winter, they are the Pacific and Atlantic energy-active zones, whereas the Arctic and South-Asian zones withstand in Siberia in summer. These facts allow an interpretation of climatic instability inherent in the region. During the autumn-winter season, the instability expresses as sharp alteration of weather cycles. The formation of Altai-Sayan cyclogenesis (which is of the same intensity as the Mediterranean) is observed for the warm seasons in the southern Siberia. In climatology it is referred as a lee-type cyclogenesis. This is the large scale phenomenon in the climatic system of the central part of Eurasia. Such specific hydrodynamic background defines environment quality in Siberia. From the point of view of system analysis, the methods of sensitivity theory, risk assessment and control along with scenario approach offer a tool which allows bringing the results of the global atmospheric and climatic studies onto the regional level. Namely, this level puts the concrete questions on the environment quality and its changes such as a choice of plausible strategy for sources control and mitigation of the man-induced impact on environment. Some environmental problems for Siberian regions are discussed, and a number of forward, adjoint and inverse problems for different risk sites and goal functionals are presented.

The impact of supplemental dietary methionine sources on volatile compound concentrations in broiler excreta.

PubMed

Chavez, C; Coufal, C D; Carey, J B; Lacey, R E; Beier, R C; Zahn, J A

2004-06-01

The impact of different Met sources on broiler fecal odor volatiles was determined by evaluating the types of sulfur compounds produced in broiler excreta. Two experiments were conducted using straight-run broiler chicks randomly distributed in battery cages, with 3 replicate pens of 16 birds each. The treatment groups were 1) dry Met hydroxy analogue (dry MetHA), 2) sodium methioninate aqueous solution (NaMet), 3) liquid Met hydroxy analogue (Liq MetHA), 4) D,L- Met, and 5) no supplemental Met (control group). The Met activities of each Met source were 52, 45.9, 88, and 98%, respectively. All diets were formulated to contain either 0.8% (experiment 1) total Met activity or 0.5% Met activity in the starter and 0.38% Met activity in the grower (experiment 2) (except the control group, 0.35% Met activity), but otherwise met NRC nutrient requirements (NRC, 1994). Diets were fed ad libitum from d 1 to 6 wk of age. There were no significant differences in BW among the treatments. All excreta were collected in litter pans lined with aluminum foil. In experiment 1, at wk 6, broiler excreta were collected for a 24-h period, and 4.5 g of broiler excreta from each treatment group was collected into 15-mL headspace vials. Samples were analyzed by gas chromatography/mass spectrometry (GC/MS). The volatile sulfur compounds that were identified and quantified in the broiler excreta were H2S, carbonyl sulfide (COS), methyl mercaptan (CH3SH), dimethyl disulfide (CH3SSCH3), and dimethyl trisulfide (CH3SSSCH3). The NaMet treatment group had significantly higher concentrations of H2S, COS, and CH3SSCH3 compared with all other treatment groups. The Liq MetHA group had significantly lower concentrations of H2S, COS, CH3SH, and CH3SSCH3 compared with the other treatment groups. The dry MetHA group significantly had the highest concentration of CH4SH. The D,L-Met treatment group had the significantly highest concentration of CH3SSSCH3 and the lowest concentration of H2S. The control group had the significantly lowest concentrations of CH3SH, CH3SSCH3, and CH3SSSCH3 compared with the other treatment groups. In experiment 2, at wk 6, an electronic nose was used to evaluate 15 air samples per treatment group. In addition, 15 air samples (containing 6 to 8 L of air in a Tedlar bag, 3 samples per treatment group) were collected for odor evaluation by a sensory panel. Electronic nose sensor data revealed that volatile compounds in broiler excreta from the control group were significantly different from the other 4 treatment groups. Evaluation of the air samples by a sensory panel determined that there was a statistically significant difference in odor threshold detection between the control group and the other treatment groups. The dilutions to threshold of control group, NaMet, dry MetHA, Liq MetHA, and D,L-Met were 350, 492, 568, 496, and 526 odor units, respectively. These findings demonstrate that dietary Met sources significantly influenced odorous volatile concentrations in broiler excreta.

The biofilm-controlling functions of rechargeable antimicrobial N-halamine dental unit waterline tubing.

PubMed

Porteous, Nuala; Schoolfield, John; Luo, Jie; Sun, Yuyu

2011-01-01

A study was conducted to test the biofilm-controlling functions of N-halamine tubing over an eight-month period. A laboratory system, simulating a teaching dental clinic, was used to test rechargeable N-halamine tubing (T) compared to an untreated control (C) using the unit manufacturer's tubing. For the long-term study, a recharged tubing (RC) treated with bleach was used to compare with the test (T) and the control (C) tubing. Source tap water was cycled through the lines at 1.4 mL/minute, five minutes on and 25 minutes off, eight hours/day, five days/week. Every three weeks, samples of effluent, recovered adherent bacteria from inside tubing surfaces, and SEM images were examined for bacterial and biofilm growth. After sampling, a recharging solution of chlorine bleach (1 : 10 dilution) was run through T and RC lines, left overnight, and rinsed out the next morning. One-way ANOVAs and Spearman correlations were performed to detect significant differences for T, RC, and C, and determine significance with time period and source water, respectively. Mean log CFU/mL for C effluent > T (p = 0.028), and C tubing > T (p = 0.035). Spearman correlations were significant between effluent and source water level for T (rho = 0.817), and T tubing (0.750); between RC tubing and source water level (rho = 0.836), and time (rho = 0.745); and between C and time (rho = 0.873). SEM imaging confirmed the presence of biofilm inside RC and C, but not inside T. N-halamine tubing completely inhibited biofilm formation without negatively affecting the physical properties of the effluent water. Further research on N-halamine tubing using a pure water source is recommended, as T effluent bacterial levels reflected the source tap water quality and proliferation of planktonic bacteria with no biofilm activity.

The Biofilm-Controlling Functions of Rechargeable Antimicrobial N-halamine Dental Unit Waterline Tubing

PubMed Central

Porteous, Nuala; Schoolfield, John; Luo, Jie; Sun, Yuyu

2015-01-01

Objective A study was conducted to test the biofilm-controlling functions of N-halamine tubing over an eight-month period. Methods A laboratory system, simulating a teaching dental clinic, was used to test rechargeable N-halamine tubing (T) compared to an untreated control (C) using the unit manufacturer’s tubing. For the long-term study, a recharged tubing (RC) treated with bleach was used to compare with the test (T) and the control (C) tubing. Source tap water was cycled through the lines at 1.4 mL/minute, five minutes on and 25 minutes off, eight hours/day, five days/week. Every three weeks, samples of effluent, recovered adherent bacteria from inside tubing surfaces, and SEM images were examined for bacterial and biofilm growth. After sampling, a recharging solution of chlorine bleach (1:10 dilution) was run through T and RC lines, left overnight, and rinsed out the next morning. One-way ANOVAs and Spearman correlations were performed to detect significant differences for T, RC, and C, and determine significance with time period and source water, respectively. Results Mean log CFU/mL for C effluent > T (p = 0.028), and C tubing > T (p = 0.035). Spearman correlations were significant between effluent and source water level for T (rho = 0.817), and T tubing (0.750); between RC tubing and source water level (rho = 0.836), and time (rho = 0.745); and between C and time (rho = 0.873). SEM imaging confirmed the presence of biofilm inside RC and C, but not inside T. Conclusion N-halamine tubing completely inhibited biofilm formation without negatively affecting the physical properties of the effluent water. Further research on N-halamine tubing using a pure water source is recommended, as T effluent bacterial levels reflected the source tap water quality and proliferation of planktonic bacteria with no biofilm activity. PMID:22403982

SOXF factors regulate murine satellite cell self-renewal and function through inhibition of β-catenin activity.

PubMed

Alonso-Martin, Sonia; Auradé, Frédéric; Mademtzoglou, Despoina; Rochat, Anne; Zammit, Peter S; Relaix, Frédéric

2018-06-08

Muscle satellite cells are the primary source of stem cells for postnatal skeletal muscle growth and regeneration. Understanding genetic control of satellite cell formation, maintenance, and acquisition of their stem cell properties is on-going, and we have identified SOXF (SOX7, SOX17, SOX18) transcriptional factors as being induced during satellite cell specification. We demonstrate that SOXF factors regulate satellite cell quiescence, self-renewal and differentiation. Moreover, ablation of Sox17 in the muscle lineage impairs postnatal muscle growth and regeneration. We further determine that activities of SOX7, SOX17 and SOX18 overlap during muscle regeneration, with SOXF transcriptional activity requisite. Finally, we show that SOXF factors also control satellite cell expansion and renewal by directly inhibiting the output of β-catenin activity, including inhibition of Ccnd1 and Axin2 . Together, our findings identify a key regulatory function of SoxF genes in muscle stem cells via direct transcriptional control and interaction with canonical Wnt/β-catenin signaling. © 2018, Alonso-Martin et al.

Clinical and scientific importance of source control in abdominal infections: summary of a symposium

PubMed Central

Bohnen, John M.A.; Marshall, John C.; Fry, Donald E.; Johnson, Steven B.; Solomkin, Joseph S.

1999-01-01

In May 1997, a panel of surgeon-investigators met to discuss the clinical importance and research implications of controlling the source of abdominal infections. It was concluded that source control is critical to therapeutic success and that antimicrobial therapy and other adjunctive interventions will fail if the source of infection is not controlled by resection, exteriorization or other means. The panelists presented different definitions of source control, depending on the scientific purpose of the definition. All participants agreed that failure to consider the adequacy of source control of infection has limited the value of most clinical trials of therapeutic anti-infective agents. Besides recognizing source control as an essential goal of patient care, the panelists emphasized the need for further investigative work to define, record and stratify the adequacy of source control in clinical trials of therapeutic agents for abdominal infections. PMID:10223073

Mechanisms and models of REM sleep control.

PubMed

McCarley, R W

2004-07-01

The first sections of this paper survey the history and recent developments relevant to the major neurotransmitters and neuromodulators involved in REM sleep control. The last portion of this paper proposes a structural model of cellular interaction that produces the REM sleep cycle, and constitutes a further revision of the reciprocal interaction model This paper proposes seven criteria to define a causal role in REM sleep control for putative neuro-transmitters/modulators. The principal criteria are measurements during behavioral state changes of the extracellular concentrations of the putative substances, and electrophysiological recording of their neuronal source. A cautionary note is that, while pharmacological manipulations are suggestive, they alone do not provide definitive causal evidence. The extensive body of in vivo and in vitro evidence supporting cholinergic promotion of REM sleep via LDT/PPT neuronal activity is surveyed. An interesting question raised by some studies is whether cholinergic influences in rat are less puissant than in cat. At least some of the apparent lesser REM-inducing effect of carbachol in the rat may be due to incomplete control of circadian influences; almost all experiments have been run only in the daytime, inactive period, when REM sleep is more prominent, rather than in the REM-sparse nighttime inactive period. Monoaminergic inhibition of cholinergic neurons, once thought to be the most shaky proposal of the reciprocal interaction model, now enjoys considerable support from both in vivo and in vitro data. However, the observed time course of monoaminergic neurons, their "turning off" discharge activity as REM sleep is approached and entered would seem to be difficult to produce from feedback inhibition, as originally postulated by the reciprocal interaction model. New data suggest the possibility that GABAergic inhibition of Locus Coeruleus and Dorsal Raphe monoaminergic neurons may account for the "REM-off" neurons turning off. However, the source(s) of GABAergic influences suggested by anatomical studies has yet to be definitively identified by electrophysiological recordings of GABAergic neurons that show the requisite inverse time course of activity relative to monoaminergic neurons. New and still preliminary microdialysis data suggest that reticular formation neurons, the effector neurons for REM sleep phenomena, might be disinhibited during REM sleep by decreased GABAergic influence, perhaps stemming from REM-on cholinergic neuronal inhibition of reticular formation GABAergic neurons. Whether the postulated cholinergic inhibition of GABAergic neurons is present is testable with in vitro recordings and double labeling. Taking into account the observed data on neuro-modulators/transmitters, a structural model incorporating interaction of REM-on and REM-off neurons and GABAergic influences is proposed. Finally, with respect to orexin and REM sleep, it is hypothesized that orexinergic activity may be a principal factor controlling REM sleep's absence from the active period in strongly circadian animals such as rat and man.

Bacteriophages and dairy fermentations

PubMed Central

Marcó, Mariángeles Briggiler; Moineau, Sylvain; Quiberoni, Andrea

2012-01-01

This review highlights the main strategies available to control phage infection during large-scale milk fermentation by lactic acid bacteria. The topics that are emphasized include the factors influencing bacterial activities, the sources of phage contamination, the methods available to detect and quantify phages, as well as practical solutions to limit phage dispersion through an adapted factory design, the control of air flow, the use of adequate sanitizers, the restricted used of recycled products, and the selection and growth of bacterial cultures. PMID:23275866

Respiratory source control using a surgical mask: An in vitro study.

PubMed

Patel, Rajeev B; Skaria, Shaji D; Mansour, Mohamed M; Smaldone, Gerald C

2016-07-01

Cough etiquette and respiratory hygiene are forms of source control encouraged to prevent the spread of respiratory infection. The use of surgical masks as a means of source control has not been quantified in terms of reducing exposure to others. We designed an in vitro model using various facepieces to assess their contribution to exposure reduction when worn at the infectious source (Source) relative to facepieces worn for primary (Receiver) protection, and the factors that contribute to each. In a chamber with various airflows, radiolabeled aerosols were exhaled via a ventilated soft-face manikin head using tidal breathing and cough (Source). Another manikin, containing a filter, quantified recipient exposure (Receiver). The natural fit surgical mask, fitted (SecureFit) surgical mask and an N95-class filtering facepiece respirator (commonly known as an "N95 respirator") with and without a Vaseline-seal were tested. With cough, source control (mask or respirator on Source) was statistically superior to mask or unsealed respirator protection on the Receiver (Receiver protection) in all environments. To equal source control during coughing, the N95 respirator must be Vaseline-sealed. During tidal breathing, source control was comparable or superior to mask or respirator protection on the Receiver. Source control via surgical masks may be an important adjunct defense against the spread of respiratory infections. The fit of the mask or respirator, in combination with the airflow patterns in a given setting, are significant contributors to source control efficacy. Future clinical trials should include a surgical mask source control arm to assess the contribution of source control in overall protection against airborne infection.

A non-ideal portal frame energy harvester controlled using a pendulum

NASA Astrophysics Data System (ADS)

Iliuk, I.; Balthazar, J. M.; Tusset, A. M.; Piqueira, J. R. C.; Rodrigues de Pontes, B.; Felix, J. L. P.; Bueno, Á. M.

2013-09-01

A model of energy harvester based on a simple portal frame structure is presented. The system is considered to be non-ideal system (NIS) due to interaction with the energy source, a DC motor with limited power supply and the system structure. The nonlinearities present in the piezoelectric material are considered in the piezoelectric coupling mathematical model. The system is a bi-stable Duffing oscillator presenting a chaotic behavior. Analyzing the average power variation, and bifurcation diagrams, the value of the control variable that optimizes power or average value that stabilizes the chaotic system in the periodic orbit is determined. The control sensitivity is determined to parametric errors in the damping and stiffness parameters of the portal frame. The proposed passive control technique uses a simple pendulum to tuned to the vibration of the structure to improve the energy harvesting. The results show that with the implementation of the control strategy it is possible to eliminate the need for active or semi active control, usually more complex. The control also provides a way to regulate the energy captured to a desired operating frequency.

CD14+CD33+ myeloid cell-CCL11-eosinophil signature in ulcerative colitis.

PubMed

Lampinen, Maria; Waddell, Amanda; Ahrens, Richard; Carlson, Marie; Hogan, Simon P

2013-11-01

This study tested the hypothesis that eotaxins (CCL11, CCL24, and CCL26) and IL-5 contribute to eosinophil recruitment to the intestine in UC and that intestinal macrophages are important producers of CCL11 in this disease. Peripheral blood and rectal biopsy samples were obtained from patients with active (n=18) and quiescent UC (n=9), and control patients (n=7). Eosinophil and macrophage levels and activation were analyzed by flow cytometry. Rectal mRNA levels of CCL11, CCL24, CCL26, and IL-5 were determined by qRT-PCR. The cellular source of CCL11 was visualized by immunofluorescence analyses. Eosinophil numbers were elevated in the blood and rectum of active and quiescent UC patients compared with controls. Levels of activated eosinophils (CD66b(high)) correlated with disease severity. Rectal CCL11, CCL24, and CCL26 mRNA levels were increased in active UC, whereas only CCL11 was elevated in quiescent UC. Levels of CCL11, but not CCL24 and CCL26, positively correlated with eosinophil numbers. Numbers of CD14(+)CD33(+) cells correlated with CCL11 and eosinophil levels. Immunofluorescence analyses revealed the presence of CD14(+)CCL11(+) mononuclear cells in colonic biopsies in UC. These results support the hypothesis that CCL11 contributes to eosinophil recruitment in UC and that intestinal myeloid cells are a source of CCL11. Interestingly, rectal levels of CCL24, CCL26, and IL-5 only increase during active UC, coinciding with further elevation of eosinophil numbers and with the activation of rectal eosinophils. In conclusion, there is a link among CD14(+)CD33(+) myeloid cells, CCL11, and eosinophils in adult UC.

CD14+CD33+ myeloid cell-CCL11-eosinophil signature in ulcerative colitis

PubMed Central

Lampinen, Maria; Waddell, Amanda; Ahrens, Richard; Carlson, Marie; Hogan, Simon P.

2013-01-01

This study tested the hypothesis that eotaxins (CCL11, CCL24, and CCL26) and IL-5 contribute to eosinophil recruitment to the intestine in UC and that intestinal macrophages are important producers of CCL11 in this disease. Peripheral blood and rectal biopsy samples were obtained from patients with active (n=18) and quiescent UC (n=9), and control patients (n=7). Eosinophil and macrophage levels and activation were analyzed by flow cytometry. Rectal mRNA levels of CCL11, CCL24, CCL26, and IL-5 were determined by qRT-PCR. The cellular source of CCL11 was visualized by immunofluorescence analyses. Eosinophil numbers were elevated in the blood and rectum of active and quiescent UC patients compared with controls. Levels of activated eosinophils (CD66bhigh) correlated with disease severity. Rectal CCL11, CCL24, and CCL26 mRNA levels were increased in active UC, whereas only CCL11 was elevated in quiescent UC. Levels of CCL11, but not CCL24 and CCL26, positively correlated with eosinophil numbers. Numbers of CD14+CD33+ cells correlated with CCL11 and eosinophil levels. Immunofluorescence analyses revealed the presence of CD14+CCL11+ mononuclear cells in colonic biopsies in UC. These results support the hypothesis that CCL11 contributes to eosinophil recruitment in UC and that intestinal myeloid cells are a source of CCL11. Interestingly, rectal levels of CCL24, CCL26, and IL-5 only increase during active UC, coinciding with further elevation of eosinophil numbers and with the activation of rectal eosinophils. In conclusion, there is a link among CD14+CD33+ myeloid cells, CCL11, and eosinophils in adult UC. PMID:23904440

Analysis and experimental evaluation of shunt active power filter for power quality improvement based on predictive direct power control.

PubMed

Aissa, Oualid; Moulahoum, Samir; Colak, Ilhami; Babes, Badreddine; Kabache, Nadir

2017-10-12

This paper discusses the use of the concept of classical and predictive direct power control for shunt active power filter function. These strategies are used to improve the active power filter performance by compensation of the reactive power and the elimination of the harmonic currents drawn by non-linear loads. A theoretical analysis followed by a simulation using MATLAB/Simulink software for the studied techniques has been established. Moreover, two test benches have been carried out using the dSPACE card 1104 for the classic and predictive DPC control to evaluate the studied methods in real time. Obtained results are presented and compared in this paper to confirm the superiority of the predictive technique. To overcome the pollution problems caused by the consumption of fossil fuels, renewable energies are the alternatives recommended to ensure green energy. In the same context, the tested predictive filter can easily be supplied by a renewable energy source that will give its impact to enhance the power quality.

In vitro bioanalysis of drinking water from source to tap.

PubMed

Rosenmai, Anna Kjerstine; Lundqvist, Johan; le Godec, Théo; Ohlsson, Åsa; Tröger, Rikard; Hellman, Björn; Oskarsson, Agneta

2018-08-01

The presence of chemical pollutants in sources of drinking water is a key environmental problem threatening public health. Efficient removal of pollutants in drinking water treatment plants (DWTPs) is needed as well as methods for assessment of the total impact of all present chemicals on water quality. In the present study we have analyzed the bioactivity of water samples from source to tap, including effects of various water treatments in a DWTP, using a battery of cell-based bioassays, covering health-relevant endpoints. Reporter gene assays were used to analyze receptor activity of the aryl hydrocarbon receptor (AhR), estrogen receptor (ER), androgen receptor (AR), peroxisome proliferator-activated receptor alpha (PPARα) and induction of oxidative stress by the nuclear factor erythroid 2-related factor 2 (Nrf2). DNA damage was determined by Comet assay. Grab water samples were concentrated by HLB or ENV solid phase extraction and the water samples assayed at a relative enrichment factor of 50. The enrichment procedure did not induce any bioactivity. No bioactivity was detected in Milli-Q water or drinking water control samples. Induction of AhR, ER and Nrf2 activities was revealed in source to tap water samples. No cytotoxicity, PPARα or AR antagonist activity, or DNA damage were observed in any of the water samples. A low AR agonist activity was detected in a few samples of surface water, but not in the samples from the DWTP. The treatment steps at the DWTP, coagulation, granulated activated carbon filtration, UV disinfection and NH 2 Cl dosing had little or no effect on the AhR, Nrf2 and ER bioactivity. However, nanofiltration and passage through the distribution network drastically decreased AhR activity, while the effect on Nrf2 activity was more modest and no apparent effect was observed on ER activity. The present results suggest that bioassays are useful tools for evaluation of the efficiency of different treatment steps in DWTPs in reducing toxic activities. Bioassays of AhR and Nrf2 are useful for screening of effects of a broad range of chemicals in drinking water and ER activity can be monitored with a high sensitivity. Copyright © 2018 Elsevier Ltd. All rights reserved.

Impact of dose calibrators quality control programme in Argentina

NASA Astrophysics Data System (ADS)

Furnari, J. C.; de Cabrejas, M. L.; del C. Rotta, M.; Iglicki, F. A.; Milá, M. I.; Magnavacca, C.; Dima, J. C.; Rodríguez Pasqués, R. H.

1992-02-01

The national Quality Control (QC) programme for radionuclide calibrators started 12 years ago. Accuracy and the implementation of a QC programme were evaluated over all these years at 95 nuclear medicine laboratories where dose calibrators were in use. During all that time, the Metrology Group of CNEA has distributed 137Cs sealed sources to check stability and has been performing periodic "checking rounds" and postal surveys using unknown samples (external quality control). An account of the results of both methods is presented. At present, more of 65% of the dose calibrators measure activities with an error less than 10%.

Effects of Behavioral Activation on the Quality of Life and Emotional State of Lung Cancer and Breast Cancer Patients During Chemotherapy Treatment.

PubMed

Fernández-Rodríguez, Concepción; Villoria-Fernández, Erica; Fernández-García, Paula; González-Fernández, Sonia; Pérez-Álvarez, Marino

2017-12-01

Research suggests that the progressive abandonment of activities in cancer patients are related to depression and worse quality of life. Behavioral activation (BA) encourages subjects to activate their sources of reinforcement and modify the avoidance responses. This study assesses the effectiveness of BA in improving quality of life and preventing emotional disorders during chemotherapy treatment. One sample of lung cancer patients and another of breast cancer patients were randomized into a BA experimental group (E.G. lung/4sess . n = 50; E.G. breast/6sess . n = 33) and a control group (C.G. lung/4sess . n = 40; C.G. breast/6sess. n = 35), respectively. In each session and in follow-ups (3/6/9 months), all participants completed different assessment scales. The results converge to show the effectiveness of BA, encouraging cancer patients to maintain rewarding activities which can activate their sources of day-to-day reinforcement and modify their experience avoidance patterns. BA appears to be a practical intervention which may improve social and role functioning and the emotional state of cancer patients during chemotherapy treatment.

Antibiotics in the aquatic environment of Vietnam: Sources, concentrations, risk and control strategy.

PubMed

Binh, Vu Ngan; Dang, Nhung; Anh, Nguyen Thi Kieu; Ky, Le Xuan; Thai, Phong K

2018-04-01

The presence of antibiotics in the aquatic environment is a serious concern because it may lead to the emergence of antibiotic resistance, thus lowering the therapeutic effect of antibiotics. In Vietnam, the problem is aggravated by the irrational use of antibiotics in different sectors of agriculture and human health service. Moreover, the residues of antibiotics in the aquatic environment can be spread widely due to the lack of proper wastewater treatment systems. In this paper, we aim to comprehensively review all relevant sources that discharge antibiotics to the aquatic environment in Vietnam. Apart from the common source of antibiotics from aquaculture, other activities that release considerable amounts of antibiotics into water environment are also included. Environmental concentrations of antibiotics related to those sources are studied to demonstrate their contributions to the presence of antibiotics in the aquatic environment in Vietnam. As antibiotic-contained water may be used as water supply for irrigation and even human consumption in rural areas, the essence of wastewater treatment is highlighted. Finally, we also discuss the new National Action plan from the Ministry of Health for controlling the issue of antibiotic resistance in Vietnam. Copyright © 2018 Elsevier Ltd. All rights reserved.

Incorrect predictions reduce switch costs.

PubMed

Kleinsorge, Thomas; Scheil, Juliane

2015-07-01

In three experiments, we combined two sources of conflict within a modified task-switching procedure. The first source of conflict was the one inherent in any task switching situation, namely the conflict between a task set activated by the recent performance of another task and the task set needed to perform the actually relevant task. The second source of conflict was induced by requiring participants to guess aspects of the upcoming task (Exps. 1 & 2: task identity; Exp. 3: position of task precue). In case of an incorrect guess, a conflict accrues between the representation of the guessed task and the actually relevant task. In Experiments 1 and 2, incorrect guesses led to an overall increase of reaction times and error rates, but they reduced task switch costs compared to conditions in which participants predicted the correct task. In Experiment 3, incorrect guesses resulted in faster performance overall and to a selective decrease of reaction times in task switch trials when the cue-target interval was long. We interpret these findings in terms of an enhanced level of controlled processing induced by a combination of two sources of conflict converging upon the same target of cognitive control. Copyright © 2015 Elsevier B.V. All rights reserved.

NASA One-Dimensional Combustor Simulation--User Manual for S1D_ML

NASA Technical Reports Server (NTRS)

Stueber, Thomas J.; Paxson, Daniel E.

2014-01-01

The work presented in this paper is to promote research leading to a closed-loop control system to actively suppress thermo-acoustic instabilities. To serve as a model for such a closed-loop control system, a one-dimensional combustor simulation composed using MATLAB software tools has been written. This MATLAB based process is similar to a precursor one-dimensional combustor simulation that was formatted as FORTRAN 77 source code. The previous simulation process requires modification to the FORTRAN 77 source code, compiling, and linking when creating a new combustor simulation executable file. The MATLAB based simulation does not require making changes to the source code, recompiling, or linking. Furthermore, the MATLAB based simulation can be run from script files within the MATLAB environment or with a compiled copy of the executable file running in the Command Prompt window without requiring a licensed copy of MATLAB. This report presents a general simulation overview. Details regarding how to setup and initiate a simulation are also presented. Finally, the post-processing section describes the two types of files created while running the simulation and it also includes simulation results for a default simulation included with the source code.

Four GABAergic interneurons impose feeding restraint in Drosophila

PubMed Central

Pool, Allan-Hermann; Kvello, Pal; Mann, Kevin; Cheung, Samantha K.; Gordon, Michael D.; Wang, Liming; Scott, Kristin

2014-01-01

Summary Feeding is dynamically regulated by the palatability of the food source and the physiological needs of the animal. How consumption is controlled by external sensory cues and internal metabolic state remains under intense investigation. Here, we identify four GABAergic interneurons in the Drosophila brain that establish a central feeding threshold which is required to inhibit consumption. Inactivation of these cells results in indiscriminate and excessive intake of all compounds, independent of taste quality or nutritional state. Conversely, acute activation of these neurons suppresses consumption of water and nutrients. The output from these neurons is required to gate activity in motor neurons that control meal initiation and consumption. Thus, our study reveals a new layer of inhibitory control in feeding circuits that is required to suppress a latent state of unrestricted and non-selective consumption. PMID:24991960

Mixtures of Olive Pomace with Different Nitrogen Sources for the Control of Meloidogyne spp. on Tomato

PubMed Central

Rodríguez-Kábana, R.; Estaún, V.; Pinochet, J.; Marfá, O.

1995-01-01

The efficacy of mixtures of dry olive (Olea europea) pomace with biuret, guanidine, and melamine for control of root-knot nematodes (Meloidogyne spp.) on tomato (Lycopersicon esculentum) was studied in greenhouse experiments. Olive pomace (OP) applied pre-plant at 10 g/kg soil was phytotoxic. Mixtures of OP (10 g/kg soil) with biuret or guanidine at 200-300 mg/kg soil reduced or eliminated the phytotoxic effect, controlled root-knot nematodes, and increased soil esterase activity indicative of microbial activity. The addition of biuret or guanidine without OP to soil at rates <300 mg/kg soil did not control root-knot nematodes. Melamine applied at 100-400 mg/kg soil was phytotoxic as were mixtures of melamine with OP. Treatment of OP with anhydrous ammonia increased N content of the material. In another greenhouse experiment, NH₃-treated OP added to soil was not phytotoxic to tomato, suppressed root-knot nematodes, and increased soil esterase activity. Greenhouse and microplot experiments with OP plus chicken litter demonstrated the efficacy of these combination amendments to control root-knot nematodes and increase tomato yields in Meloidogyne-infested soil. PMID:19277325

Evaluating the purity of a {sup 57}Co flood source by PET

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

DiFilippo, Frank P., E-mail: difilif@ccf.org

2014-11-01

Purpose: Flood sources of {sup 57}Co are commonly used for quality control of gamma cameras. Flood uniformity may be affected by the contaminants {sup 56}Co and {sup 58}Co, which emit higher energy photons. Although vendors specify a maximum combined {sup 56}Co and {sup 58}Co activity, a convenient test for flood source purity that is feasible in a clinical environment would be desirable. Methods: Both {sup 56}Co and {sup 58}Co emit positrons with branching 19.6% and 14.9%, respectively. As is known from {sup 90}Y imaging, a positron emission tomography (PET) scanner is capable of quantitatively imaging very weak positron emission inmore » a high single-photon background. To evaluate this approach, two {sup 57}Co flood sources were scanned with a clinical PET/CT multiple times over a period of months. The {sup 56}Co and {sup 58}Co activity was clearly visible in the reconstructed PET images. Total impurity activity was quantified from the PET images after background subtraction of prompt gamma coincidences. Results: Time-of-flight PET reconstruction was highly beneficial for accurate image quantification. Repeated measurements of the positron-emitting impurities showed excellent agreement with an exponential decay model. For both flood sources studied, the fit parameters indicated a zero intercept and a decay half-life consistent with a mixture of {sup 56}Co and {sup 58}Co. The total impurity activity at the reference date was estimated to be 0.06% and 0.07% for the two sources, which was consistent with the vendor’s specification of <0.12%. Conclusions: The robustness of the repeated measurements and a thorough analysis of the detector corrections and physics suggest that the accuracy is acceptable and that the technique is feasible. Further work is needed to validate the accuracy of this technique with a calibrated high resolution gamma spectrometer as a gold standard, which was not available for this study, and for other PET detector models.« less

Biochemical studies of amylase, lipase and protease in Callosobruchus maculatus (Coleoptera: Chrysomelidae) populations fed with Vigna unguiculata grain cultivated with diazotrophic bacteria strains.

PubMed

Silva, L B; Torres, É B; Nóbrega, R A S; Lopes, G N; Vogado, R F; Pavan, B E; Fernandes-Junior, P I

2017-12-01

The objective of this study was to evaluate the enzymatic activity of homogenates of insects fed on grain of cowpea, Vigna unguiculata (L.), cultivars grown with different nitrogen sources. For the experiment we used aliquots of the homogenate of 100 unsexed adult insects, emerged from 10 g of grain obtained from four cowpea cultivars: 'BRS Acauã', 'BRS Carijó', 'BRS Pujante', and 'BRS Tapaihum' grown under different regimes of nitrogen sources: mineral fertilizer, inoculation with strains of diazotrophs (BR 3267, BR 3262, BR 3299; INPA 03-11B, 03-84 UFLA, as well as the control (with soil nitrogen). The parameters evaluated were enzymatic activities of insect protease, amylase and lipase and the starch content of the grains. There were differences in the enzymatic activity of amylase, lipase and protease of insect homogenate according to the food source. A lower activity of the enzyme amylase from C. maculatus homogenate was observed when insects were fed grain of the cultivar BRS Carijó. A lower activity of lipase enzyme from C. maculatus homogenate was observed when the insects fed on grain from the interaction of the cultivar Tapaihum inoculated with BR 3262 diazotrophs. The lowest proteolytic activity was observed in homogenate of insects fed on interaction of 'BRS Carijó' inoculated with BR 3262 diazotrophs. Starch content correlated positively with the amylase activity of C. maculatus homogenate. The cultivar BRS Carijó had a different behavior from the other cultivars, according to the cluster analysis.

ENA-78 is an important angiogenic factor in idiopathic pulmonary fibrosis.

PubMed

Keane, M P; Belperio, J A; Burdick, M D; Lynch, J P; Fishbein, M C; Strieter, R M

2001-12-15

Idiopathic pulmonary fibrosis (IPF) is a chronic and often fatal disorder. Fibroplasia and deposition of extracellular matrix are dependent, in part, on angiogenesis and vascular remodeling. We obtained open lung biopsies from patients undergoing thoracic surgery for reasons other than interstitial lung disease (control) (n = 78) and from patients with IPF (n = 91). We found that levels of epithelial neutrophil-activating peptide 78 (ENA-78) were greater from tissue specimens of IPF patients, as compared with control subjects. When ENA-78 was depleted from IPF tissue specimens, tissue-derived angiogenic activity was markedly reduced. Immunolocalization of ENA-78 demonstrated that hyperplastic Type II pneumocytes and macrophages were the predominant cellular sources of ENA-78. These findings support the notion that ENA-78 may be an important additional factor that regulates angiogenic activity in IPF.

The effects of analgesics on central processing of tonic pain: A cross-over placebo controlled study.

PubMed

Lelic, Dina; Hansen, Tine M; Mark, Esben B; Olesen, Anne E; Drewes, Asbjørn M

2017-09-01

Opioids and antidepressants that inhibit serotonin and norepinephrine reuptake (SNRI) are recognized as analgesics to treat moderate to severe pain, but the central mechanisms underlying their analgesia remain unclear. This study investigated how brain activity at rest and exposed to tonic pain is modified by oxycodone (opioid) and venlafaxine (SNRI). Twenty healthy males were included in this randomized, cross-over, double-blinded study. 61-channel electroencephalogram (EEG) was recorded before and after five days of treatment with placebo, oxycodone (10 mg extended release b.i.d) or venlafaxine (37.5 mg extended release b.i.d) at rest and during tonic pain (hand immersed in 2 °C water for 80 s). Subjective pain and unpleasantness scores of tonic pain were recorded. Spectral analysis and sLORETA source localization were done in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta1 (12-18 Hz) and beta2 (18-32 Hz) frequency bands. Oxycodone decreased pain and unpleasantness scores (P < 0.05), whereas venlafaxine decreased the pain scores (P < 0.05). None of the treatments changed the spectral indices or brain sources underlying resting EEG. Venlafaxine decreased spectral indices in alpha band of the EEG to tonic pain, whereas oxycodone decreased the spectral indices and brain source activity in delta and theta frequency bands (all P < 0.05). The brain source activity predominantly decreased in the insula and inferior frontal gyrus. The decrease of activity within insula and inferior frontal gyrus is likely involved in pain inhibition due to oxycodone treatment, whereas the decrease in alpha activity is likely involved in pain inhibition due to venlafaxine treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impact of Converter Interfaced Generation and Load on Grid Performance

NASA Astrophysics Data System (ADS)

Ramasubramanian, Deepak

Alternate sources of energy such as wind, solar photovoltaic and fuel cells are coupled to the power grid with the help of solid state converters. Continued deregulation of the power sector coupled with favorable government incentives has resulted in the rapid growth of renewable energy sources connected to the distribution system at a voltage level of 34.5kV or below. Of late, many utilities are also investing in these alternate sources of energy with the point of interconnection with the power grid being at the transmission level. These converter interfaced generation along with their associated control have the ability to provide the advantage of fast control of frequency, voltage, active, and reactive power. However, their ability to provide stability in a large system is yet to be investigated in detail. This is the primary objective of this research. In the future, along with an increase in the percentage of converter interfaced renewable energy sources connected to the transmission network, there exists a possibility of even connecting synchronous machines to the grid through converters. Thus, all sources of energy can be expected to be coupled to the grid through converters. The control and operation of such a grid will be unlike anything that has been encountered till now. In this dissertation, the operation and behavior of such a grid will be investigated. The first step in such an analysis will be to build an accurate and simple mathematical model to represent the corresponding components in commercial software. Once this bridge has been crossed, conventional machines will be replaced with their solid state interfaced counterparts in a phased manner. At each stage, attention will be devoted to the control of these sources and also on the stability performance of the large power system. This dissertation addresses various concerns regarding the control and operation of a futuristic power grid. In addition, this dissertation also aims to address the issue of whether a requirement may arise to redefine operational reliability criteria based on the results obtained.

Decline in Chinese lake phosphorus concentration accompanied by shift in sources since 2006

NASA Astrophysics Data System (ADS)

Tong, Yindong; Zhang, Wei; Wang, Xuejun; Couture, Raoul-Marie; Larssen, Thorjørn; Zhao, Yue; Li, Jing; Liang, Huijiao; Liu, Xueyan; Bu, Xiaoge; He, Wei; Zhang, Qianggong; Lin, Yan

2017-07-01

Domestic wastewater and agricultural activities are important sources of nutrient pollutants such as phosphorus and nitrogen. Upon reaching freshwater, these nutrients can lead to extensive growth of harmful algae, which results in eutrophication. Many Chinese lakes are subject to such eutrophication, especially in highly polluted areas, and as such, understanding nutrient fluxes to these lakes offers insights into the varying processes governing pollutant fluxes as well as lake water quality. Here we analyse water quality data, recorded between 2006 and 2014 in 862 freshwater lakes in four geographical regions of China, to assess the input of phosphorus from human activity. We find that improvements in sanitation of both rural and urban domestic wastewater have resulted in large-scale declines in lake phosphorus concentrations in the most populated parts of China. In more sparsely populated regions, diffuse sources such as aquaculture and livestock farming offset this decline. Anthropogenic deforestation and soil erosion may also offset decreases in point sources of pollution. In the light of these regional differences, we suggest that a spatially flexible set of policies for water quality control would be beneficial for the future health of Chinese lakes.

InP MMIC Chip Set for Power Sources Covering 80-170 GHz

NASA Technical Reports Server (NTRS)

Ngo, Catherine

2001-01-01

We will present a Monolithic Millimeter-wave Integrated Circuit (MMIC) chip set which provides high output-power sources for driving diode frequency multipliers into the terahertz range. The chip set was fabricated at HRL Laboratories using a 0.1-micrometer gate-length InAlAs/InGaAs/InP high electron mobility transistor (HEMT) process, and features transistors with an f(sub max) above 600 GHz. The HRL InP HEMT process has already demonstrated amplifiers in the 60-200 GHz range. In this paper, these high frequency HEMTs form the basis for power sources up to 170 GHz. A number of state-of-the-art InP HEMT MMICs will be presented. These include voltage-controlled and fixed-tuned oscillators, power amplifiers, and an active doubler. We will first discuss an 80 GHz voltage-controlled oscillator with 5 GHz of tunability and at least 17 mW of output power, as well as a 120 GHz oscillator providing 7 mW of output power. In addition, we will present results of a power amplifier which covers the full WRIO waveguide band (75-110 GHz), and provides 40-50 mW of output power. Furthermore, we will present an active doubler at 164 GHz providing 8% bandwidth, 3 mW of output power, and an unprecedented 2 dB of conversion loss for an InP HEMT MMIC at this frequency. Finally, we will demonstrate a power amplifier to cover 140-170 GHz with 15-25 mW of output power and 8 dB gain. These components can form a power source in the 155-165 GHz range by cascading the 80 GHz oscillator, W-band power amplifier, 164 GHz active doubler and final 140-170 GHz power amplifier for a stable, compact local oscillator subsystem, which could be used for atmospheric science or astrophysics radiometers.

Robust Low-Cost Cathode for Commercial Applications

NASA Technical Reports Server (NTRS)

Patterson, Michael J.

2007-01-01

Under funding from the NASA Commercial Technology Office, a cathode assembly was designed, developed, fabricated, and tested for use in plasma sources for ground-based materials processing applications. The cathode development activity relied on the large prior NASA investment and successful development of high-current, high-efficiency, long-life hollow cathodes for use on the International Space Station Plasma Contactor System. The hollow cathode was designed and fabricated based on known engineering criteria and manufacturing processes for compatibility with the requirements of the plasma source. The transfer of NASA GRC-developed hollow cathode technology for use as an electron emitter in the commercial plasma source is anticipated to yield a significant increase in process control, while eliminating the present issues of electron emitter lifetime and contamination.

Factors controlling the regional distribution of vanadium in ground water

USGS Publications Warehouse

Wright, Michael T.; Belitz, Kenneth

2010-01-01

Although the ingestion of vanadium (V) in drinking water may have possible adverse health effects, there have been relatively few studies of V in groundwater. Given the importance of groundwater as a source of drinking water in many areas of the world, this study examines the potential sources and geochemical processes that control the distribution of V in groundwater on a regional scale. Potential sources of V to groundwater include dissolution of V rich rocks, and waste streams from industrial processes. Geochemical processes such as adsorption/desorption, precipitation/dissolution, and chemical transformations control V concentrations in groundwater. Based on thermodynamic data and laboratory studies, V concentrations are expected to be highest in samples collected from oxic and alkaline groundwater. However, the extent to which thermodynamic data and laboratory results apply to the actual distribution of V in groundwater is not well understood. More than 8400 groundwater samples collected in California were used in this study. Of these samples, high (> or = 50 μg/L) and moderate (25 to 49 μg/L) V concentrations were most frequently detected in regions where both source rock and favorable geochemical conditions occurred. The distribution of V concentrations in groundwater samples suggests that significant sources of V are mafic and andesitic rock. Anthropogenic activities do not appear to be a significant contributor of V to groundwater in this study. High V concentrations in groundwater samples analyzed in this study were almost always associated with oxic and alkaline groundwater conditions, which is consistent with predictions based on thermodynamic data.

Voluntary control over prestimulus activity related to encoding

PubMed Central

Gruber, Matthias J.; Otten, Leun J.

2010-01-01

A new development in our understanding of human long-term memory is that effective memory formation relies on neural activity just before an event. It is unknown whether such prestimulus activity is under voluntary control or a reflection of random fluctuations over time. In the present study, we addressed two issues: (i) whether prestimulus activity is influenced by an individual's motivation to encode, and (ii) at what point in time encoding-related activity emerges. Electrical brain activity was recorded while healthy male and female adults memorized series of words. Each word was preceded by a cue, which indicated the monetary reward that would be received if the following word was later remembered. Memory was tested after a short delay with a five-way recognition task to separate different sources of recognition. Electrical activity elicited by the reward cue predicted later memory of a word. Crucially, however, this was only observed when the incentive to memorize a word was high. Encoding-related activity preceded high reward words that were later recollected. This activity started shortly after cue onset and persisted until word onset. Prestimulus activity thus not only signals cue-related processing, but also an ensuing preparatory state. In contrast, reward-related activity was limited to the time period immediately following the reward cue. These findings indicate that engaging neural activity that benefits the encoding of an upcoming event is under voluntary control, reflecting a strategic preparatory state in anticipation of processing an event. PMID:20660262

Geothermic analysis of high temperature hydrothermal activities area in Western plateau of Sichuan province, China

NASA Astrophysics Data System (ADS)

Zhang, J.

2016-12-01

There is a high temperature hydrothermal activity area in the western plateau of Sichuan. More than 200 hot springs points have been found in the region, including 11 hot spring water temperature above local boiling point. Most of these distribute along Jinshajjiang fracture, Dege-Xiangcheng fracture, Ganzi-Litang fracture as well as Xianshuihe fracture, and form three high-temperature hydrothermal activity strips in the NW-SE direction. Using gravity, magnetic, seismic and helium isotope data, this paper analyzed the crust-mantle heat flow structure, crustal heat source distribution and water heating system. The results show that the geothermal activity mainly controlled by the "hot" crust. The ratio of crustal heat flow and surface heat flow is higher than 60%. In the high temperature hydrothermal activities area, there is lower S wave velocity zone with Vs<3.2 km/s in 15 30 km depth in middle and lower crust. Basing on the S wave velocity inversion temperature of crust-mantle, it has been found that there is a high temperature layer with 850 1000 ° in 20 40 km depth. It is the main heat source of high temperature hydrothermal activity area of western Sichuan. Our argument is that atmospheric precipitation, surface water infiltrated along the fault fracture into the crustal deep, heating by crustal hot source, and circulation to surface become high temperature hot water. Geothermal water mainly reserve in the Triassic strata of the containing water good carbonate rocks, and in the intrusive granite which is along the fault zone. The thermal energy of Surface heat thermal activities mainly comes from the high-temperature hot source which is located in the middle and lower crust. Being in the deep crustal fracture, the groundwater infiltrated to the deep crust and absorbed heat, then, quickly got back to the surface and formed high hot springs.

Respiratory source control using a surgical mask: An in vitro study

PubMed Central

Patel, Rajeev B.; Skaria, Shaji D.; Mansour, Mohamed M.; Smaldone, Gerald C.

2016-01-01

ABSTRACT Cough etiquette and respiratory hygiene are forms of source control encouraged to prevent the spread of respiratory infection. The use of surgical masks as a means of source control has not been quantified in terms of reducing exposure to others. We designed an in vitro model using various facepieces to assess their contribution to exposure reduction when worn at the infectious source (Source) relative to facepieces worn for primary (Receiver) protection, and the factors that contribute to each. In a chamber with various airflows, radiolabeled aerosols were exhaled via a ventilated soft-face manikin head using tidal breathing and cough (Source). Another manikin, containing a filter, quantified recipient exposure (Receiver). The natural fit surgical mask, fitted (SecureFit) surgical mask and an N95-class filtering facepiece respirator (commonly known as an “N95 respirator”) with and without a Vaseline-seal were tested. With cough, source control (mask or respirator on Source) was statistically superior to mask or unsealed respirator protection on the Receiver (Receiver protection) in all environments. To equal source control during coughing, the N95 respirator must be Vaseline-sealed. During tidal breathing, source control was comparable or superior to mask or respirator protection on the Receiver. Source control via surgical masks may be an important adjunct defense against the spread of respiratory infections. The fit of the mask or respirator, in combination with the airflow patterns in a given setting, are significant contributors to source control efficacy. Future clinical trials should include a surgical mask source control arm to assess the contribution of source control in overall protection against airborne infection. PMID:26225807

Goals and intentions mediate efficacy beliefs and declining physical activity in high school girls.

PubMed

Dishman, Rod K; Saunders, Ruth P; Felton, Gwen; Ward, Dianne S; Dowda, Marsha; Pate, Russ R

2006-12-01

According to theory, girls who set goals about increasing their physical activity and who are dissatisfied with their current activity level are likely to form intentions to be active and to carry out those intentions, especially if they have high efficacy and control beliefs about being physically active. We tested those ideas while observing naturally occurring change during high school. A cohort of 431 black and white girls was tested at the end of their 9th- and 12th-grade academic years. Confirmatory factor analysis established the structural invariance of the measures across the 3-year study period. Structural equation modeling and panel analysis were used to determine whether changes in goal setting and satisfaction would mediate relations of self-efficacy and perceived behavioral control with changes in intention and physical activity. Testing occurred between February and May in 1999 and 2004. Data were analyzed in 2006. Goal setting and intention mediated the indirect relation between self-efficacy and change in physical activity. Perceived behavioral control and physical activity change were related directly and also indirectly by a path mediated through satisfaction and intention. Black girls had lower self-efficacy, but changes in other variables were unrelated to race. These observations of longitudinal relations elaborate application of self-efficacy theory and the theory of planned behavior to physical activity by showing that goal setting and satisfaction mediate the relations of self-efficacy and perceived behavioral control with changes in intention and physical activity. The results encourage additional research to identify the sources and development of physical activity goals, and their attainment, among girls, and whether experimental manipulation of goals and intentions can mitigate the decline in girls' physical activity during high school.

Impacts of Oil and Gas Production on Winter Ozone Pollution in the Uintah Basin Using Model Source Apportionment

NASA Astrophysics Data System (ADS)

Tran, H. N. Q.; Tran, T. T.; Mansfield, M. L.; Lyman, S. N.

2014-12-01

Contributions of emissions from oil and gas activities to elevated ozone concentrations in the Uintah Basin - Utah were evaluated using the CMAQ Integrated Source Apportionment Method (CMAQ-ISAM) technique, and were compared with the results of traditional budgeting methods. Unlike the traditional budgeting method, which compares simulations with and without emissions of the source(s) in question to quantify its impacts, the CMAQ-ISAM technique assigns tags to emissions of each source and tracks their evolution through physical and chemical processes to quantify the final ozone product yield from the source. Model simulations were performed for two episodes in winter 2013 of low and high ozone to provide better understanding of source contributions under different weather conditions. Due to the highly nonlinear ozone chemistry, results obtained from the two methods differed significantly. The growing oil and gas industry in the Uintah Basin is the largest contributor to the elevated zone (>75 ppb) observed in the Basin. This study therefore provides an insight into the impact of oil and gas industry on the ozone issue, and helps in determining effective control strategies.

Oxygen isotopes as a tracer of phosphate sources and cycling in aquatic systems (Invited)

NASA Astrophysics Data System (ADS)

Young, M. B.; Kendall, C.; Paytan, A.

2013-12-01

The oxygen isotopic composition of phosphate can provide valuable information about sources and processes affecting phosphorus as it moves through hydrologic systems. Applications of this technique in soil and water have become more common in recent years due to improvements in extraction methods and instrument capabilities, and studies in multiple aquatic environments have demonstrated that some phosphorus sources may have distinct isotopic compositions within a given system. Under normal environmental conditions, the oxygen-phosphorus bonds in dissolved inorganic phosphate (DIP) can only be broken by enzymatic activity. Biological cycling of DIP will bring the phosphate oxygen into a temperature-dependent equilibrium with the surrounding water, overprinting any existing isotopic source signals. However, studies conducted in a wide range of estuarine, freshwater, and groundwater systems have found that the phosphate oxygen is often out of biological equilibrium with the water, suggesting that it is common for at least a partial isotopic source signal to be retained in aquatic systems. Oxygen isotope analysis on various potential phosphate sources such as synthetic and organic fertilizers, animal waste, detergents, and septic/wastewater treatment plant effluents show that these sources span a wide range of isotopic compositions, and although there is considerable overlap between the source groups, sources may be isotopically distinct within a given study area. Recent soil studies have shown that isotopic analysis of phosphate oxygen is also useful for understanding microbial cycling across different phosphorus pools, and may provide insights into controls on phosphorus leaching. Combining stable isotope information from soil and water studies will greatly improve our understanding of complex phosphate cycling, and the increasing use of this isotopic technique across different environments will provide new information regarding anthropogenic phosphate inputs and controls on biological cycling within hydrologic systems.

Energy to the Edge (E2E) U.S. Army Rapid Equipping Force

DTIC Science & Technology

2014-03-21

generators, parallel multiple sources, prioritize loads, and balance loads. Smart grids are based on complex algorithms and controls. 3. Reduce...stations are not able to be s rviced by prim power because of their location in the middle of a very active airfield and fueling a syst m that c ist

On the sources of vegetation activity variation, and their relation with water balance in Mexico

Treesearch

F. Mora; L.R. Iverson

1998-01-01

Natural landscape surface processes are largely controlled by the relationship between climate and vegetation. Water balance integrates the effects of climate on patterns of vegetation distribution and productivity, and for that season, functional relationships can be established using water balance variables as predictors of vegetation response. In this study, we...

Shape Memory Alloy Actuator

NASA Technical Reports Server (NTRS)

Baumbick, Robert J. (Inventor)

2000-01-01

The present invention discloses and teaches a unique, remote optically controlled micro actuator particularly suitable for aerospace vehicle applications wherein hot gas, or in the alternative optical energy, is employed as the medium by which shape memory alloy elements are activated. In gas turbine powered aircraft the source of the hot gas may be the turbine engine compressor or turbine sections.

Shape Memory Alloy Actuator

NASA Technical Reports Server (NTRS)

Baumbick, Robert J. (Inventor)

2002-01-01

The present invention discloses and teaches a unique, remote optically controlled micro actuator particularly suitable for aerospace vehicle applications wherein hot gas, or in the alternative optical energy, is employed as the medium by which shape memory alloy elements are activated. In gas turbine powered aircraft the source of the hot gas may be the turbine engine compressor or turbine sections.

Phospholipase A2 as a point of care alternative to serum amylase and pancreatic lipase

NASA Astrophysics Data System (ADS)

Liu, Nathan J.; Chapman, Robert; Lin, Yiyang; Bentham, Andrew; Tyreman, Matthew; Philips, Natalie; Khan, Shahid A.; Stevens, Molly M.

2016-06-01

Acute pancreatitis is a relatively common and potentially fatal condition, but the presenting symptoms are non-specific and diagnosis relies largely on the measurement of amylase activity by the hospital clinical laboratory. In this work we develop a point of care test for pancreatitis measuring concentration of secretory phospholipase A2 group IB (sPLA2-IB). Novel antibodies for sPLA2-IB were raised and used to design an ELISA and a lateral flow device (LFD) for the point of care measurement of sPLA2-IB concentration, which was compared to pancreatic amylase activity, lipase activity, and sPLA2-IB activity in 153 serum samples. 98 of these samples were obtained from the pathology unit of a major hospital and classified retrospectively according to presence or absence of pancreatitis, and the remaining 55 were obtained from commercial sources to serve as high lipase (n = 20), CA19-9 positive (n = 15), and healthy (n = 20) controls. sPLA2-IB concentration correlated well with the serum activity of both amylase and lipase, and performed at least as well as either markers in the differentiation of pancreatitis from controls.Acute pancreatitis is a relatively common and potentially fatal condition, but the presenting symptoms are non-specific and diagnosis relies largely on the measurement of amylase activity by the hospital clinical laboratory. In this work we develop a point of care test for pancreatitis measuring concentration of secretory phospholipase A2 group IB (sPLA2-IB). Novel antibodies for sPLA2-IB were raised and used to design an ELISA and a lateral flow device (LFD) for the point of care measurement of sPLA2-IB concentration, which was compared to pancreatic amylase activity, lipase activity, and sPLA2-IB activity in 153 serum samples. 98 of these samples were obtained from the pathology unit of a major hospital and classified retrospectively according to presence or absence of pancreatitis, and the remaining 55 were obtained from commercial sources to serve as high lipase (n = 20), CA19-9 positive (n = 15), and healthy (n = 20) controls. sPLA2-IB concentration correlated well with the serum activity of both amylase and lipase, and performed at least as well as either markers in the differentiation of pancreatitis from controls. Electronic supplementary information (ESI) available: Additional characterisation and statistical analysis. See DOI: 10.1039/c6nr03376h

Contamination characteristics and source apportionment of trace metals in soils around Miyun Reservoir.

PubMed

Chen, Haiyang; Teng, Yanguo; Chen, Ruihui; Li, Jiao; Wang, Jinsheng

2016-08-01

Due to their toxicity and bioaccumulation, trace metals in soils can result in a wide range of toxic effects on animals, plants, microbes, and even humans. Recognizing the contamination characteristics of soil metals and especially apportioning their potential sources are the necessary preconditions for pollution prevention and control. Over the past decades, several receptor models have been developed for source apportionment. Among them, positive matrix factorization (PMF) has gained popularity and was recommended by the US Environmental Protection Agency as a general modeling tool. In this study, an extended chemometrics model, multivariate curve resolution-alternating least squares based on maximum likelihood principal component analysis (MCR-ALS/MLPCA), was proposed for source apportionment of soil metals and applied to identify the potential sources of trace metals in soils around Miyun Reservoir. Similar to PMF, the MCR-ALS/MLPCA model can incorporate measurement error information and non-negativity constraints in its calculation procedures. Model validation with synthetic dataset suggested that the MCR-ALS/MLPCA could extract acceptable recovered source profiles even considering relatively larger error levels. When applying to identify the sources of trace metals in soils around Miyun Reservoir, the MCR-ALS/MLPCA model obtained the highly similar profiles with PMF. On the other hand, the assessment results of contamination status showed that the soils around reservoir were polluted by trace metals in slightly moderate degree but potentially posed acceptable risks to the public. Mining activities, fertilizers and agrochemicals, and atmospheric deposition were identified as the potential anthropogenic sources with contributions of 24.8, 14.6, and 13.3 %, respectively. In order to protect the drinking water source of Beijing, special attention should be paid to the metal inputs to soils from mining and agricultural activities.

Alaskan North Slope petroleum systems

USGS Publications Warehouse

Magoon, L.B.; Lillis, P.G.; Bird, K.J.; Lampe, C.; Peters, K.E.

2003-01-01

Six North Slope petroleum systems are identified, described, and mapped using oil-to-oil and oil-to-source rock correlations, pods of active source rock, and overburden rock packages. To map these systems, we assumed that: a) petroleum source rocks contain 3.2 wt. % organic carbon (TOC); b) immature oil-prone source rocks have hydrogen indices (HI) >300 (mg HC/gm TOC); c) the top and bottom of the petroleum (oil plus gas) window occur at vitrinite reflectance values of 0.6 and 1.0% Ro, respectively; and d) most hydrocarbons are expelled within the petroleum window. The six petroleum systems we have identified and mapped are: a) a southern system involving the Kuna-Lisburne source rock unit that was active during the Late Jurassic and Early Cretaceous; b) two western systems involving source rock in the Kingak-Blankenship, and GRZ-lower Torok source rock units that were active during the Albian; and c) three eastern systems involving the Shublik-Otuk, Hue Shale and Canning source rock units that were active during the Cenozoic. The GRZ-lower Torok in the west is correlative with the Hue Shale to the east. Four overburden rock packages controlled the time of expulsion and gross geometry of migration paths: a) a southern package of Early Cretaceous and older rocks structurally-thickened by early Brooks Range thrusting; b) a western package of Early Cretaceous rocks that filled the western part of the foreland basin; c) an eastern package of Late Cretaceous and Paleogene rocks that filled the eastern part of the foreland basin; and d) an offshore deltaic package of Neogene rocks deposited by the Colville, Canning, and Mackenzie rivers. This petroleum system poster is part of a series of Northern Alaska posters on modeling. The poster in this session by Saltus and Bird present gridded maps for the greater Northern Alaskan onshore and offshore that are used in the 3D modeling poster by Lampe and others. Posters on source rock units are by Keller and Bird as well as Peters and others. Sandstone and shale compaction properties used in sedimentary basin modeling are covered in a poster by Rowan and others. The results of this modeling exercise will be used in our next Northern Alaska oil and gas resource assessment.

Attribution of the French human Salmonellosis cases to the main food-sources according to the type of surveillance data.

PubMed

David, J M; Sanders, P; Bemrah, N; Granier, S A; Denis, M; Weill, F-X; Guillemot, D; Watier, L

2013-05-15

Salmonella are the most common bacterial cause of foodborne infections in France and ubiquitous pathogens present in many animal productions. Assessing the relative contribution of the different food-animal sources to the burden of human cases is a key step towards the conception, prioritization and assessment of efficient control policy measures. For this purpose, we considered a Bayesian microbial subtyping attribution approach based on a previous published model (Hald et al., 2004). It requires quality integrated data on human cases and on the contamination of their food sources, per serotype and microbial subtype, which were retrieved from the French integrated surveillance system for Salmonella. The quality of the data available for such an approach is an issue for many countries in which the surveillance system has not been designed for this purpose. In France, the sources are monitored simultaneously by an active, regulation-based surveillance system that produces representative prevalence data (as ideally required for the approach) and a passive system relying on voluntary laboratories that produces data not meeting the standards set by Hald et al. (2004) but covering a broader range of sources. These data allowed us to study the impact of data quality on the attribution results, globally and focusing on specific features of the data (number of sources and contamination indicator). The microbial subtyping attribution model was run using an adapted parameterization previously proposed (David et al., 2012). A total of 9076 domestic sporadic cases were included in the analyses as well as 9 sources among which 5 were common to the active and the passive datasets. The greatest impact on the attribution results was observed for the number of sources. Thus, especially in the absence of data on imported products, the attribution estimates presented here should be considered with caution. The results were comparable for both types of surveillance, leading to the conclusion that passive data constitute a potential cost-effective complement to active data collection, especially interesting because the former encompass a greater number of sources. The model appeared robust to the type of surveillance, and provided that some methodological aspects of the model can be enhanced, it could also serve as a risk-based guidance tool for active surveillance systems. Copyright © 2013 Elsevier B.V. All rights reserved.

Integrated Microfluidic Membrane Transistor Utilizing Chemical Information for On-Chip Flow Control.

PubMed

Frank, Philipp; Schreiter, Joerg; Haefner, Sebastian; Paschew, Georgi; Voigt, Andreas; Richter, Andreas

2016-01-01

Microfluidics is a great enabling technology for biology, biotechnology, chemistry and general life sciences. Despite many promising predictions of its progress, microfluidics has not reached its full potential yet. To unleash this potential, we propose the use of intrinsically active hydrogels, which work as sensors and actuators at the same time, in microfluidic channel networks. These materials transfer a chemical input signal such as a substance concentration into a mechanical output. This way chemical information is processed and analyzed on the spot without the need for an external control unit. Inspired by the development electronics, our approach focuses on the development of single transistor-like components, which have the potential to be used in an integrated circuit technology. Here, we present membrane isolated chemical volume phase transition transistor (MIS-CVPT). The device is characterized in terms of the flow rate from source to drain, depending on the chemical concentration in the control channel, the source-drain pressure drop and the operating temperature.

Medical catheters thermally manipulated by fiber optic bundles

DOEpatents

Chastagner, P.

1992-10-06

A maneuverable medical catheter comprising a flexible tube having a functional tip is described. The catheter is connected to a control source. The functional tip of the catheter carries a plurality of temperature activated elements arranged in parallel and disposed about the functional tip and held in spaced relation at each end. These elements expand when they are heated. A plurality of fiber optic bundles, each bundle having a proximal end attached to the control source and a distal end attached to one of the elements carry light into the elements where the light is absorbed as heat. By varying the optic fiber that is carrying the light and the intensity of the light, the bending of the elements can be controlled and thus the catheter steered. In an alternate embodiment, the catheter carries a medical instrument for gathering a sample of tissue. The instrument may also be deployed and operated by thermal expansion and contraction of its moving parts. 10 figs.

Integrated Microfluidic Membrane Transistor Utilizing Chemical Information for On-Chip Flow Control

PubMed Central

Frank, Philipp; Schreiter, Joerg; Haefner, Sebastian; Paschew, Georgi; Voigt, Andreas; Richter, Andreas

2016-01-01

Microfluidics is a great enabling technology for biology, biotechnology, chemistry and general life sciences. Despite many promising predictions of its progress, microfluidics has not reached its full potential yet. To unleash this potential, we propose the use of intrinsically active hydrogels, which work as sensors and actuators at the same time, in microfluidic channel networks. These materials transfer a chemical input signal such as a substance concentration into a mechanical output. This way chemical information is processed and analyzed on the spot without the need for an external control unit. Inspired by the development electronics, our approach focuses on the development of single transistor-like components, which have the potential to be used in an integrated circuit technology. Here, we present membrane isolated chemical volume phase transition transistor (MIS-CVPT). The device is characterized in terms of the flow rate from source to drain, depending on the chemical concentration in the control channel, the source-drain pressure drop and the operating temperature. PMID:27571209