Science.gov

Sample records for active device area

  1. Active cleaning technique device

    NASA Technical Reports Server (NTRS)

    Shannon, R. L.; Gillette, R. B.

    1973-01-01

    The objective of this program was to develop a laboratory demonstration model of an active cleaning technique (ACT) device. The principle of this device is based primarily on the technique for removing contaminants from optical surfaces. This active cleaning technique involves exposing contaminated surfaces to a plasma containing atomic oxygen or combinations of other reactive gases. The ACT device laboratory demonstration model incorporates, in addition to plasma cleaning, the means to operate the device as an ion source for sputtering experiments. The overall ACT device includes a plasma generation tube, an ion accelerator, a gas supply system, a RF power supply and a high voltage dc power supply.

  2. Field studies of beach cones as coastal erosion control/reversal devices for areas with significant oil and gas activities

    SciTech Connect

    Not Available

    1992-07-17

    A field demonstration/study of a novel shoreline erosion protection device called beach cones is planned. These patented, fiberglass- reinforced concreted devices are to be deployed in a number of geometric patterns at seven location in the Bastian Bay area of Western Plaquemines Parish. The purpose of the work described in this report was to evaluate the proposed study's impact on living and non-living shellfish resources within each of the project's seven separate Study Areas. Major accomplishments for this reporting period were as follows: aerial photographs of the experimental sites were taken; all permit applications were filed; information was submitted for the Environmental Report; several reconnaissance trips to the experimental sites were made; meetings were held among all participating organizations to further plan the research; permit was obtained from the US Army Corps of Engineers; test sites were surveyed by the Xavier University contingent; survey data were taken at all sites; the Oyster Assessment was completed; permit was obtained from the State of Louisiana Department of Natural Resources; and initial survey data were finalized at all sites.

  3. Silicon active photonic devices

    NASA Astrophysics Data System (ADS)

    Dimitropoulos, Dimitrios

    Active photonic devices utilizing the optical nonlinearities of silicon have emerged in the last 5 years and the effort for commercial photonic devices in the material that has been the workhorse of electronics has been building up since. This dissertation presents the theory for some of these devices. We are concerned herein with CW lasers, amplifiers and wavelength converters that are based on the Raman effect. There have already been cursory experimental demonstrations of these devices and some of their limitations are already apparent. Most of the limitations observed are because of the appearance of effects that are competing with stimulated Raman scattering. Under the high optical powers that are necessary for the Raman effect (tens to hundrends of mW's) the process of optical two-photon (TPA) absorption occurs. The absorption of optical power that it causes itself is weak but in the process electrons and holes are generated which can further absorb light through the free-carrier absorption effect (FCA). The effective "lifetime" that these carriers have determines the magnitude of the FCA loss. We present a model for the carrier lifetime in Silicon-On-Insulator (SOI) waveguides and numerical simulations to understand how this critical parameter varies and how it can be controlled. A p-i-n junction built along SOI waveguides can help achieve lifetime of the order of 20--100 ps but the price one has to pay is on-chip electrical power consumption on the order of 100's of mWs. We model CW Raman lasers and we find that the carrier lifetime reduces the output power. If the carrier lifetime exceeds a certain "critical" value optical losses become overwhelming and lasing is impossible. As we show, in amplifiers, the nonlinear loss does not only result in diminished gain, but also in a higher noise figure. Finally the effect of Coherent anti-Stokes Raman scattering (CARS) is examined. The effect is important because with a pump frequency at 1434nm coherent power

  4. Semiconductor-based, large-area, flexible, electronic devices

    DOEpatents

    Goyal, Amit

    2011-03-15

    Novel articles and methods to fabricate the same resulting in flexible, large-area, triaxially textured, single-crystal or single-crystal-like, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  5. Radiation sensitive area detection device and method

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor); Hecht, Diana L. (Inventor); Witherow, William K. (Inventor)

    1991-01-01

    A radiation sensitive area detection device for use in conjunction with an X ray, ultraviolet or other radiation source is provided which comprises a phosphor containing film which releases a stored diffraction pattern image in response to incoming light or other electromagnetic wave. A light source such as a helium-neon laser, an optical fiber capable of directing light from the laser source onto the phosphor film and also capable of channelling the fluoresced light from the phosphor film to an integrating sphere which directs the light to a signal processing means including a light receiving means such as a photomultiplier tube. The signal processing means allows translation of the fluoresced light in order to detect the original pattern caused by the diffraction of the radiation by the original sample. The optical fiber is retained directly in front of the phosphor screen by a thin metal holder which moves up and down across the phosphor screen and which features a replaceable pinhole which allows easy adjustment of the resolution of the light projected onto the phosphor film. The device produces near real time images with high spatial resolution and without the distortion that accompanies prior art devices employing photomultiplier tubes. A method is also provided for carrying out radiation area detection using the device of the invention.

  6. X ray sensitive area detection device

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor); Witherow, William K. (Inventor); Pusey, Marc L. (Inventor); Yost, Vaughn H. (Inventor)

    1990-01-01

    A radiation sensitive area detection device is disclosed which comprises a phosphor-containing film capable of receiving and storing an image formed by a pattern of incoming x rays, UV, or other radiation falling on the film. The device is capable of fluorescing in response to stimulation by a light source in a manner directly proportional to the stored radiation pattern. The device includes: (1) a light source capable of projecting light or other appropriate electromagnetic wave on the film so as to cause it to fluoresce; (2) a means to focus the fluoresced light coming from the phosphor-containing film after light stimulation; and (3) at least one charged coupled detector or other detecting element capable of receiving and digitizing the pattern of fluoresced light coming from the phosphor-containing film. The device will be able to generate superior x ray images of high resolution from a crystal or other sample and will be particularly advantageous in that instantaneous near-real-time images of rapidly deteriorating samples can be obtained. Furthermore, the device can be made compact and sturdy, thus capable of carrying out x ray or other radiation imaging under a variety of conditions, including those experienced in space.

  7. Dual control active superconductive devices

    DOEpatents

    Martens, Jon S.; Beyer, James B.; Nordman, James E.; Hohenwarter, Gert K. G.

    1993-07-20

    A superconducting active device has dual control inputs and is constructed such that the output of the device is effectively a linear mix of the two input signals. The device is formed of a film of superconducting material on a substrate and has two main conduction channels, each of which includes a weak link region. A first control line extends adjacent to the weak link region in the first channel and a second control line extends adjacent to the weak link region in the second channel. The current flowing from the first channel flows through an internal control line which is also adjacent to the weak link region of the second channel. The weak link regions comprise small links of superconductor, separated by voids, through which the current flows in each channel. Current passed through the control lines causes magnetic flux vortices which propagate across the weak link regions and control the resistance of these regions. The output of the device taken across the input to the main channels and the output of the second main channel and the internal control line will constitute essentially a linear mix of the two input signals imposed on the two control lines. The device is especially suited to microwave applications since it has very low input capacitance, and is well suited to being formed of high temperature superconducting materials since all of the structures may be formed coplanar with one another on a substrate.

  8. Field studies of beach cones as coastal erosion control/reversal devices for areas with significant oil and gas activities. Final report, February 24, 1992--September 18, 1995

    SciTech Connect

    Law, V.J.

    1995-09-18

    The primary objective of this project was to evaluate the utility of a device called the {open_quotes}beach cone{close_quotes} in combating coastal erosion. Seven initial sites were selected for testing beach cones in a variety of geometric configurations. Permits were obtained from the State of Louisiana and the U.S. Army Corps of Engineers to perform the work associated with this study. Six hundred beach cones were actually installed at six of the sites in late July and early August, 1992. Findings indicate that beach cones accreted significant amounts of materials along the beach of a barrier island, and they might have been instrumental in repairing an approximately 200 meter gap in the island. At the eighth installation the amount of accreted material was measured by surveys to be 2200 cubic meters (2900 cubic yards) in February of 1993, when the cones were found to have been completely covered by the material. At other test sites, accretion rates have been less dramatic but importantly, no significant additional erosion has occurred, which is a positive result. The cost of sediment accretion using beach cones was found to be about $13.72 per cubic yard, which would be much lower if the cones were mass produced (on the order of $3.00 per cubic yard). The survival of the cones through the fringes of Hurricane Andrew indicates that they can be anchored sufficiently to survive significant storms. The measurements of the cones settling rates indicate that this effect is not significant enough to hinder their effectiveness. A subcontract to Xavier University to assess the ecological quality of the experimental sites involved the study of the biogeochemical cycle of trace metals. The highest concentration of heavy metals were near a fishing camp while the lowest levels were in the beach sand of a barrier island. This suggests that the metals do not occur naturally in these areas, but have been placed in the sediments by man`s activities.

  9. Modeling a Dry Etch Process for Large-Area Devices

    SciTech Connect

    Buss, R.J.; Hebner, G.A.; Ruby, D.S.; Yang, P.

    1999-07-28

    There has been considerable interest in developing dry processes which can effectively replace wet processing in the manufacture of large area photovoltaic devices. Environmental and health issues are a driver for this activity because wet processes generally increase worker exposure to toxic and hazardous chemicals and generate large volumes of liquid hazardous waste. Our work has been directed toward improving the performance of screen-printed solar cells while using plasma processing to reduce hazardous chemical usage.

  10. Personal Area Networks in Tactical Mobile Devices

    DTIC Science & Technology

    2014-08-01

    INFORMATION This work described in this report was performed by the Composeable Services Branch (Code 53628) of the C2 Technology and Experimentation...Figures 1. Data size vs . time ............................................................................................................... 4 2. PAN...devices are said to transmit 100 m. They transmit at a maximum of 100 mW (20 dBm ). 3 2. PAN EXPERIMENTATION 2.1 PURPOSE Researchers use PAN

  11. Activated-Carbon Sorbent With Integral Heat-Transfer Device

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Yavrouian, Andre

    1996-01-01

    Prototype adsorption device used, for example, in adsorption heat pump, to store natural gas to power automobile, or to separate components of fluid mixtures. Device includes activated carbon held together by binder and molded into finned heat-transfer device providing rapid heating or cooling to enable rapid adsorption or desorption of fluids. Concepts of design and fabrication of device equally valid for such other highly thermally conductive devices as copper-finned tubes, and for such other high-surface-area sorbents as zeolites or silicates.

  12. Probing a Device's Active Atoms.

    PubMed

    Studniarek, Michał; Halisdemir, Ufuk; Schleicher, Filip; Taudul, Beata; Urbain, Etienne; Boukari, Samy; Hervé, Marie; Lambert, Charles-Henri; Hamadeh, Abbass; Petit-Watelot, Sebastien; Zill, Olivia; Lacour, Daniel; Joly, Loïc; Scheurer, Fabrice; Schmerber, Guy; Da Costa, Victor; Dixit, Anant; Guitard, Pierre André; Acosta, Manuel; Leduc, Florian; Choueikani, Fadi; Otero, Edwige; Wulfhekel, Wulf; Montaigne, François; Monteblanco, Elmer Nahuel; Arabski, Jacek; Ohresser, Philippe; Beaurepaire, Eric; Weber, Wolfgang; Alouani, Mébarek; Hehn, Michel; Bowen, Martin

    2017-03-13

    Materials science and device studies have, when implemented jointly as "operando" studies, better revealed the causal link between the properties of the device's materials and its operation, with applications ranging from gas sensing to information and energy technologies. Here, as a further step that maximizes this causal link, the paper focuses on the electronic properties of those atoms that drive a device's operation by using it to read out the materials property. It is demonstrated how this method can reveal insight into the operation of a macroscale, industrial-grade microelectronic device on the atomic level. A magnetic tunnel junction's (MTJ's) current, which involves charge transport across different atomic species and interfaces, is measured while these atoms absorb soft X-rays with synchrotron-grade brilliance. X-ray absorption is found to affect magnetotransport when the photon energy and linear polarization are tuned to excite FeO bonds parallel to the MTJ's interfaces. This explicit link between the device's spintronic performance and these FeO bonds, although predicted, challenges conventional wisdom on their detrimental spintronic impact. The technique opens interdisciplinary possibilities to directly probe the role of different atomic species on device operation, and shall considerably simplify the materials science iterations within device research.

  13. Platelet actively cooled thermal management devices

    NASA Astrophysics Data System (ADS)

    Mueggenburg, H. H.; Hidahl, J. W.; Kessler, E. L.; Rousar, D. C.

    1992-07-01

    An overview of 28 years of actively-cooled platelet thermal management devices design and development history is presented. Platelet devices are created by bonding together thin metal sheets (platelets) which contain chemically-etched coolant pasages. The bonding process produces an intricate and precise matrix of coolant passages and structural walls contained within a monolithic structure. Thirteen specific applications for platelet thermal management devices are described. These devices are cooled using convective, film, and transpiration cooling techniques. Platelet thermal management devices have been fabricated from a variety of metals, cooled with a variety of fluids, and operated at heat fluxes up to 200 Btu/sq in.-sec.

  14. [100] or [110] aligned, semiconductor-based, large-area, flexible, electronic devices

    DOEpatents

    Goyal, Amit

    2015-03-24

    Novel articles and methods to fabricate the same resulting in flexible, large-area, [100] or [110] textured, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  15. Explosively activated egress area

    NASA Technical Reports Server (NTRS)

    Bement, L. J.; Bailey, J. W. (Inventor)

    1983-01-01

    A lightweight, add on structure which employs linear shaped pyrotechnic charges to smoothly cut an airframe along an egress area periphery is provided. It compromises reaction surfaces attached to the exterior surface of the airframe's skin and is designed to restrict the skin deflection. That portion of the airframe within the egress area periphery is jettisoned. Retention surfaces and sealing walls are attached to the interior surface of the airframe's skin and are designed to shield the interior of the aircraft during detonation of the pyrotechnic charges.

  16. Semiconductor-based, large-area, flexible, electronic devices on {110}<100> oriented substrates

    SciTech Connect

    Goyal, Amit

    2014-08-05

    Novel articles and methods to fabricate the same resulting in flexible, oriented, semiconductor-based, electronic devices on {110}<100> textured substrates are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  17. Field studies of beach cones as coastal erosion control/reversal devices for areas with significant oil and gas activities. [Annual report], February 24, 1992--February 23, 1993

    SciTech Connect

    Law, V.J.

    1993-03-15

    The primary objective of this project is to evaluate the utility of a device called the ``beach cone`` in combating coastal erosion. Seven initial sites were selected for testing beach cones in a variety of geometric configurations. Permits were obtained from the State of Louisiana and the US Army Corps of Engineers to perform the work associated with this study. Six hundred beach cones were actually installed at six of the sites in late July and early August, 1992. One of the initial sites was abandoned because it was found to be unsuitable for beach cone placement. The test sites have been observed for six months and preliminary findings indicate that beach cones accreted significant amounts of materials along the beach of a barrier island. At other test sites, accretion rates have been less dramatic but importantly, no significant additional erosion has occurred, which is a positive result. It is too soon to state the categorical success of the beach cones, but results to date are encouraging.

  18. Field studies of beach cones as coastal erosion control/reversal devices for areas with significant oil and gas activities. Annual report, February 24, 1993--February 23, 1994

    SciTech Connect

    Law, V.J.

    1994-07-07

    The primary objective of this project was to evaluate the utility of a device called the ``beach cone`` in combating coastal erosion. Seven initial sites were selected for testing beach cones in a variety of geometric configurations, and six sites were actually used. Six hundred beach cones were installed at the six sites in late July and early August, 1992. An additional 109 cones were installed at an eighth site in December of 1992. Findings indicate that beach cones accreted significant amounts of materials along the beach of a barrier island. At the eighth installation the amount of accreted material was measured by surveys to be 2200 cubic meters (2900 cubic yards) in February of 1993, when the cones were found to have been completely covered by the material. The average increase in elevation was about 7 inches (0. 18 in) with a maximum buildup of 3 ft. (I in). At other test sites, accretion rates have been less dramatic but importantly, no significant additional erosion has occurred, which is a positive result. The cost of sediment accretion using beach cones was found to be about $13.72 per cubic yard of sand or approximately $500,000 per mile of beach, which would be much lower if the cones were mass produced. The survival of the cones through the fringes of Hurricane Andrew indicates that they can be anchored sufficiently to survive significant storms. The measurements of the cones settling rates indicate that this effect is negligible, does not hinder their effectiveness. We do not yet have sufficient data to state the categorical success of the beach cones, but results to date are encouraging.

  19. One-step fabrication of large-area ultrathin MoS2 nanofilms with high catalytic activity for photovoltaic devices.

    PubMed

    Liang, Jia; Li, Jia; Zhu, Hongfei; Han, Yuxiang; Wang, Yanrong; Wang, Caixing; Jin, Zhong; Zhang, Gengmin; Liu, Jie

    2016-09-21

    Here we report a facile one-step solution-phase process to directly grow ultrathin MoS2 nanofilms on a transparent conductive glass as a novel high-performance counter electrode for dye-sensitized solar cells. After an appropriate reaction time, the entire surface of the conductive glass substrate was uniformly covered by ultrathin MoS2 nanofilms with a thickness of only several stacked layers. Electrochemical impedance spectroscopy and cyclic voltammetry reveal that the MoS2 nanofilms possess excellent catalytic activity towards tri-iodide reduction. When used in dye-sensitized solar cells, the MoS2 nanofilms show an impressive energy conversion efficiency of 8.3%, which is higher than that of a Pt-based electrode and very promising to be a desirable alternative counter electrode. Considering their ultrathin thickness, superior catalytic activity, simple preparation process and low cost, the as-prepared MoS2 nanofilms with high photovoltaic performance are expected to be widely employed in dye-sensitized solar cells.

  20. Neutronics activities for next generation devices

    SciTech Connect

    Gohar, Y.

    1985-01-01

    Neutronic activities for the next generation devices are the subject of this paper. The main activities include TFCX and FPD blanket/shield studies, neutronic aspects of ETR/INTOR critical issues, and neutronics computational modules for the tokamak system code and tandem mirror reactor system code. Trade-off analyses, optimization studies, design problem investigations and computational models development for reactor parametric studies carried out for these activities are summarized.

  1. [Batteries Used in Active Implantable Medical Devices].

    PubMed

    Ma, Bozhi; Hao, Hongwei; Li, Luming

    2015-03-01

    In recent years active implantable medical devices(AIMD) are being developed rapidly. Many battery systems have been developed for different AIMD applications. These batteries have the same requirements which include high safety, reliability, energy density and long service life, discharge indication. History, present and future of batteries used in AIMD are introduced in the article.

  2. Reducing contact resistance in graphene devices through contact area patterning.

    PubMed

    Smith, Joshua T; Franklin, Aaron D; Farmer, Damon B; Dimitrakopoulos, Christos D

    2013-04-23

    Performance of graphene electronics is limited by contact resistance associated with the metal-graphene (M-G) interface, where unique transport challenges arise as carriers are injected from a 3D metal into a 2D-graphene sheet. In this work, enhanced carrier injection is experimentally achieved in graphene devices by forming cuts in the graphene within the contact regions. These cuts are oriented normal to the channel and facilitate bonding between the contact metal and carbon atoms at the graphene cut edges, reproducibly maximizing "edge-contacted" injection. Despite the reduction in M-G contact area caused by these cuts, we find that a 32% reduction in contact resistance results in Cu-contacted, two-terminal devices, while a 22% reduction is achieved for top-gated graphene transistors with Pd contacts as compared to conventionally fabricated devices. The crucial role of contact annealing to facilitate this improvement is also elucidated. This simple approach provides a reliable and reproducible means of lowering contact resistance in graphene devices to bolster performance. Importantly, this enhancement requires no additional processing steps.

  3. Active superconducting devices formed of thin films

    DOEpatents

    Martens, Jon S.; Beyer, James B.; Nordman, James E.; Hohenwarter, Gert K. G.

    1991-05-28

    Active superconducting devices are formed of thin films of superconductor which include a main conduction channel which has an active weak link region. The weak link region is composed of an array of links of thin film superconductor spaced from one another by voids and selected in size and thickness such that magnetic flux can propagate across the weak link region when it is superconducting. Magnetic flux applied to the weak link region will propagate across the array of links causing localized loss of superconductivity in the links and changing the effective resistance across the links. The magnetic flux can be applied from a control line formed of a superconducting film deposited coplanar with the main conduction channel and weak link region on a substrate. The devices can be formed of any type to superconductor but are particularly well suited to the high temperature superconductors since the devices can be entirely formed from coplanar films with no overlying regions. The devices can be utilized for a variety of electrical components, including switching circuits, amplifiers, oscillators and modulators, and are well suited to microwave frequency applications.

  4. High Temperature Thermoelectric Device Concept Using Large Area PN Junctions

    NASA Astrophysics Data System (ADS)

    Chavez, R.; Angst, S.; Hall, J.; Stoetzel, J.; Kessler, V.; Bitzer, L.; Maculewicz, F.; Benson, N.; Wiggers, H.; Wolf, D.; Schierning, G.; Schmechel, R.

    2014-06-01

    A new high temperature thermoelectric device concept using large area nanostructured silicon p-type and n-type ( PN) junctions is presented. In contrast to conventional thermoelectric generators, where the n-type and p-type semiconductors are connected electrically in series and thermally in parallel, we experimentally demonstrate a device concept in which a large area PN junction made from highly doped densified silicon nanoparticles is subject to a temperature gradient parallel to the PN interface. In the proposed device concept, the electrical contacts are made at the cold side eliminating the hot side substrate and difficulties that go along with high temperature electrical contacts. This concept allows temperature gradients greater than 300 K to be experimentally applied with hot side temperatures larger than 800 K. Electronic properties of the PN junctions and power output characterizations are presented. A fundamental working principle is discussed using a particle network model with temperature and electric fields as variables, and which considers electrical conductivity and thermal conductivity according to Fourier's law, as well as Peltier and Seebeck effects.

  5. Active Optical Devices and Applications. Volume 228

    DTIC Science & Technology

    1980-04-01

    obscuration, 5-cm-thick solid, segmented (6 petals) Zerodur . Mirror A is near the limit of what can be fabricated with current technology. The honeycomb...DEW Descriptors, Keywords: Active Optical Device Application Large Optics Adaptive Technology Wavefront Sensor Deformable Mirror Performance...Cuneo, Jr., U.S. Air Force, NASA Headquarters 228-01 Wavefront sensors and deformable mirrors for visible wavelengths 4 Noah Bareket, Lockheed

  6. Active MMI devices: concept, proof, and recent progress

    NASA Astrophysics Data System (ADS)

    Hamamoto, Kiichi; Jiang, Haisong

    2015-09-01

    Multi-mode interference (MMI) couplers (waveguides) are widely studied and developed as key components of photonic integrated circuits, including power coupler/dividers, and others. Furthermore, another possibility utilizing MMI has been investigated on active devices so far. Owing to the wider area of the multi-mode waveguide section compared with that of the regular single-mode waveguide, MMI may result in higher performance (high power, low power consumption, and others) rather than conventional active devices while maintaining regular single-mode output. Thus, active multi-mode interferometer (active-MMI) devices, including laser diodes (LDs), super-luminescent light emitting diodes (SLEDs), and semiconductor optical amplifiers (SOAs) have been studied. Moreover, they have been also exploited to bi-stable LDs and single wavelength emitters, and others using the interference inside the MMI section. In this paper, we review and summarize the recent progress in active MMI devices. We provide proof of MMI phenomena in active waveguides and discuss the results.

  7. 21 CFR 890.5050 - Daily activity assist device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Daily activity assist device. 890.5050 Section 890.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5050 Daily...

  8. 21 CFR 890.5050 - Daily activity assist device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Daily activity assist device. 890.5050 Section 890.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5050 Daily...

  9. 21 CFR 890.5050 - Daily activity assist device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Daily activity assist device. 890.5050 Section 890.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5050 Daily...

  10. 21 CFR 890.5050 - Daily activity assist device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Daily activity assist device. 890.5050 Section 890.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5050 Daily...

  11. 21 CFR 890.5050 - Daily activity assist device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Daily activity assist device. 890.5050 Section 890.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5050 Daily...

  12. Graphene active plasmonics for terahertz device applications

    NASA Astrophysics Data System (ADS)

    Otsuji, Taiichi; Dubinov, Alexander; Ryzhii, Maxim; Boubanga Tombet, Stephane; Satou, Akira; Mitin, Vladimir; Shur, Michael S.; Ryzhii, Victor

    2015-05-01

    This paper reviews recent advances in the double-graphene-layer (DGL) active plasmonic heterostructures for the terahertz (THz) device applications. The DGL consists of a core shell in which a thin tunnel barrier layer is sandwiched by the two GLs being independently connected with the side contacts and outer gate stack layers at both sides. The DGL core shell works as a nano-capacitor, exhibiting inter-GL resonant tunneling (RT) when the band offset between the two GLs is aligned. The RT produces a strong nonlinearity with a negative differential conductance in the DGL current-voltage characteristics. The excitation of the graphene plasmons by the THz radiation resonantly modulates the tunneling currentvoltage characteristics. When the band offset is aligned to the THz photon energy, the DGL structure can mediate photonassisted RT, resulting in resonant emission or detection of the THz radiation. The cooperative double-resonant excitation with structure-sensitive graphene plasmons gives rise to various functionalities such as rectification (detection), photomixing, higher harmonic generation, and self-oscillation, in the THz device implementations.

  13. {100}<100> or 45.degree.-rotated {100}<100>, semiconductor-based, large-area, flexible, electronic devices

    SciTech Connect

    Goyal, Amit

    2012-05-15

    Novel articles and methods to fabricate the same resulting in flexible, {100}<100> or 45.degree.-rotated {100}<100> oriented, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.

  14. Antifungal activity of antimicrobial-impregnated devices.

    PubMed

    Darouiche, R O; Mansouri, M D; Kojic, E M

    2006-04-01

    The in-vitro and in-vivo efficacy against Candida albicans and Candida krusei of devices impregnated with chlorhexidine and chloroxylenol was examined. The impregnated devices produced large zones of inhibition against both organisms (mean size, 39 mm and 38 mm, respectively). In a rabbit model in which segments of silicone catheters were placed percutaneously, non-impregnated devices were twice as likely as impregnated devices to become colonised with either C. albicans or C. krusei. Impregnated devices also had significantly lower colony counts of C. albicans (58 vs. 1361 CFU; p 0.008) and C. krusei (19 vs. 764 CFU; p 0.008).

  15. Walking Devices Used by the Elderly Living in Rural Areas of Thailand

    PubMed Central

    Patcharawan, SUWANNARAT; THAWEEWANNAKIJ, Thiwabhorn; KAEWSANMUNG, Supapon; KAEWJOHO, Chonticha; SAENGSUWAN, Jiamjit; AMATACHAYA, Sugalya

    2015-01-01

    Background: The use of all types of external devices was previously investigated for elderly with and without orthopaedic problems of a developed country. This study describes the proportion, types and the reasons of using a walking device in elderly who live in many rural areas of Thailand. Methods: Participants (n = 390) were interviewed using a questionnaire to ascertain their demographics, health status and types of walking device required for daily activities. Results: Forty-one participants (11%) used a walking device, particularly when walking long distances due to a fear of falling, musculoskeletal pain, and impaired walking ability. The proportion of walking devices used dramatically increased in participants aged 75 years and over (six times of those aged 60–74 years). Most of the participants used a modified walking stick by their own determination (81%), while only 7% used one according to medical prescription. A significant increase in the need of a walking device was seen in participants aged 75 years and over (OR = 13.9; 95% CI 5.9–32.7; P < 0.001), with a medical problem (OR = 45.9; 95% CI 6.7–73.4; P < 0.001) and who required regular medication (OR = 12.7; 95% CI 5.0–33.6; P = 0.001). Conclusion: The findings emphasise the importance of a community health service to promote health status, particularly before 75 years of age. PMID:26023295

  16. Field studies of beach cones as coastal erosion control/reversal devices for areas with significant oil and gas activities. Technical progress report, April--June 1992 and Project status report, June 1992

    SciTech Connect

    Not Available

    1992-07-17

    A field demonstration/study of a novel shoreline erosion protection device called beach cones is planned. These patented, fiberglass- reinforced concreted devices are to be deployed in a number of geometric patterns at seven location in the Bastian Bay area of Western Plaquemines Parish. The purpose of the work described in this report was to evaluate the proposed study`s impact on living and non-living shellfish resources within each of the project`s seven separate Study Areas. Major accomplishments for this reporting period were as follows: aerial photographs of the experimental sites were taken; all permit applications were filed; information was submitted for the Environmental Report; several reconnaissance trips to the experimental sites were made; meetings were held among all participating organizations to further plan the research; permit was obtained from the US Army Corps of Engineers; test sites were surveyed by the Xavier University contingent; survey data were taken at all sites; the Oyster Assessment was completed; permit was obtained from the State of Louisiana Department of Natural Resources; and initial survey data were finalized at all sites.

  17. INSERTION DEVICE ACTIVITIES FOR NSLS-II.

    SciTech Connect

    TANABE,T.; HARDER, D.A.; HULBERT, S.; RAKOWSKI, G.; SKARITKA, J.

    2007-06-25

    National Synchrotron Light Source-II (NSLS-II) will be a medium energy storage ring of 3GeV electron beam energy with sub-nm.rad horizontal emittance and top-off capability at 500mA. Damping wigglers will be used not only to reduce the beam emittance but also used as broadband sources for users. Cryo-Permanent Magnet Undulators (CPMUs) are considered for hard X-ray linear device, and permanent magnet based elliptically polarized undulators (EPUs) for variable polarization devices for soft X-ray. 6T superconducting wiggler with minimal fan angle will be installed in the second phase as well as quasi-periodic EPU for VUV and possibly high-temperature superconducting undulator. R&D plans have been established to pursue the performance enhancement of the baseline devices and to design new types of insertion devices. A new insertion device development laboratory will also be established.

  18. Cognitive Inference Device for Activity Supervision in the Elderly

    PubMed Central

    2014-01-01

    Human activity, life span, and quality of life are enhanced by innovations in science and technology. Aging individual needs to take advantage of these developments to lead a self-regulated life. However, maintaining a self-regulated life at old age involves a high degree of risk, and the elderly often fail at this goal. Thus, the objective of our study is to investigate the feasibility of implementing a cognitive inference device (CI-device) for effective activity supervision in the elderly. To frame the CI-device, we propose a device design framework along with an inference algorithm and implement the designs through an artificial neural model with different configurations, mapping the CI-device's functions to minimise the device's prediction error. An analysis and discussion are then provided to validate the feasibility of CI-device implementation for activity supervision in the elderly. PMID:25405211

  19. Active fiber optic technologies used as tamper-indicating devices

    SciTech Connect

    Horton, P.R.V.; Waddoups, I.G.

    1995-11-01

    The Sandia National Laboratories (SNL) Safeguards and Seals Evaluation Program is evaluating new fiber optic active seal technologies for use at Department of Energy (DOE) facilities. The goal of the program is to investigate active seal technologies that can monitor secured containers storing special nuclear materials (SNM) within DOE vaults. Specifically investigated were active seal technologies that can be used as tamper-indicating devices to monitor secured containers within vaults while personnel remain outside the vault area. Such a system would allow minimal access into vaults while ensuring container content accountability. The purpose of this report is to discuss tamper-indicating devices that were evaluated for possible DOE use. While previous seal evaluations (Phase I and II) considered overall facility applications, this discussion focuses specifically on their use in vault storage situations. The report will highlight general background information, specifications and requirements, and test procedures. Also discussed are the systems available from four manufacturers: Interactive Technologies, Inc., Fiber SenSys, Inc., Inovonics, Inc., and Valve Security Systems.

  20. [2011 after-service customer satisfaction survey of monitoring devices in Shanghai area].

    PubMed

    Wang, Lijun; Li, Bin; Qian, Jianguo; Cao, Shaoping; He, Dehua; Zheng, Yunxin

    2013-01-01

    In 2011, Shanghai Medical Equipment Management Quality Control Center launched the fifth after-sale service satisfaction survey for medical devices in Shanghai area. There are 8 classes medical devices involving in the survey. This paper demonstrates the investigation results of monitoring devices which are from different manufacturers.

  1. System and method for interfacing large-area electronics with integrated circuit devices

    DOEpatents

    Verma, Naveen; Glisic, Branko; Sturm, James; Wagner, Sigurd

    2016-07-12

    A system and method for interfacing large-area electronics with integrated circuit devices is provided. The system may be implemented in an electronic device including a large area electronic (LAE) device disposed on a substrate. An integrated circuit IC is disposed on the substrate. A non-contact interface is disposed on the substrate and coupled between the LAE device and the IC. The non-contact interface is configured to provide at least one of a data acquisition path or control path between the LAE device and the IC.

  2. Antimicrobial activity of antiseptic-coated orthopaedic devices.

    PubMed

    Darouiche, R O; Green, G; Mansouri, M D

    1998-04-01

    Antimicrobial coating of medical devices, including fracture fixation devices, has evolved as a potentially effective method for preventing device-related infections. We examined the in vitro antimicrobial activity of titanium cylinders coated with the antiseptic combination of chlorhexidine and chloroxylenol. The coated devices provided zones of inhibition against Staphylococcus epidermidis, S. aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans, at baseline and up to 8 weeks after incubation of the coated cylinders in human serum at 37 degrees C. This durable antimicrobial activity was attributed to the relatively slow leaching of chlorhexidine and chloroxylenol from the coated cylinders as measured by high-performance liquid chromatography. These results suggest that antiseptic-coated orthopaedic devices may provide broad-spectrum and durable antimicrobial protection against device-related infection.

  3. MMIC devices for active phased array antennas

    NASA Technical Reports Server (NTRS)

    Mittra, R.

    1985-01-01

    Considerable progress has been made in the calculation and measurement of the scattering parameters of printed circuit discontinuities. These discontinuities occur in a variety of structures, such as transitions between rectangular waveguide and printed circuits, junctions between circuits of different dielectric constants, and filters and impedance matching circuits. Because of the variety of devices in which these discontinuities occur, it is very useful to understand them in as great a detail as possible. Both theoretical and experimental studies of discontinuities were considered. The theoretical studies have focused on finding ways to predict the scattering from discontinuities. The experimental studies have concentrated on developing measurement techniques for determining the scattering parameters of these discontinuities.

  4. Open active cloaking and illusion devices for the Laplace equation

    NASA Astrophysics Data System (ADS)

    Ma, Qian; Yang, Fan; Jin, Tian Yu; Lei Mei, Zhong; Cui, Tie Jun

    2016-04-01

    We propose open active cloaking and illusion devices for the Laplace equation. Compared with the closed configurations of active cloaking and illusion devices, we focus on improving the distribution schemes for the controlled sources, which do not have to surround the protected object strictly. Instead, the controlled sources can be placed in several small discrete clusters, and produce the desired voltages along the controlled boundary, to actively hide or disguise the protected object. Numerical simulations are performed with satisfactory results, which are further validated by experimental measurements. The open cloaking and illusion devices have many advantages over the closed configurations in various potential applications.

  5. Method for accurately positioning a device at a desired area of interest

    DOEpatents

    Jones, Gary D.; Houston, Jack E.; Gillen, Kenneth T.

    2000-01-01

    A method for positioning a first device utilizing a surface having a viewing translation stage, the surface being movable between a first position where the viewing stage is in operational alignment with a first device and a second position where the viewing stage is in operational alignment with a second device. The movable surface is placed in the first position and an image is produced with the first device of an identifiable characteristic of a calibration object on the viewing stage. The moveable surface is then placed in the second position and only the second device is moved until an image of the identifiable characteristic in the second device matches the image from the first device. The calibration object is then replaced on the stage of the surface with a test object, and the viewing translation stage is adjusted until the second device images the area of interest. The surface is then moved to the first position where the test object is scanned with the first device to image the area of interest. An alternative embodiment where the devices move is also disclosed.

  6. Development of novel active transport membrande devices

    SciTech Connect

    Laciak, D.V.

    1994-11-01

    Air Products has undertaken a research program to fabricate and evaluate gas separation membranes based upon promising ``active-transport`` (AT) materials recently developed in our laboratories. Active Transport materials are ionic polymers and molten salts which undergo reversible interaction or reaction with ammonia and carbon dioxide. The materials are useful for separating these gases from mixtures with hydrogen. Moreover, AT membranes have the unique property of possessing high permeability towards ammnonia and carbon dioxide but low permeability towards hydrogen and can thus be used to permeate these components from a gas stream while retaining hydrogen at high pressure.

  7. Geometric investigation of a gaming active device

    NASA Astrophysics Data System (ADS)

    Menna, Fabio; Remondino, Fabio; Battisti, Roberto; Nocerino, Erica

    2011-07-01

    3D imaging systems are widely available and used for surveying, modeling and entertainment applications, but clear statements regarding their characteristics, performances and limitations are still missing. The VDI/VDE and the ASTME57 committees are trying to set some standards but the commercial market is not reacting properly. Since many new users are approaching these 3D recording methodologies, clear statements and information clarifying if a package or system satisfies certain requirements before investing are fundamental for those users who are not really familiar with these technologies. Recently small and portable consumer-grade active sensors came on the market, like TOF rangeimaging cameras or low-cost triangulation-based range sensor. A quite interesting active system was produced by PrimeSense and launched on the market thanks to the Microsoft Xbox project with the name of Kinect. The article reports the geometric investigation of the Kinect active sensors, considering its measurement performances, the accuracy of the retrieved range data and the possibility to use it for 3D modeling application.

  8. Applications of large-area nanopatterning to energy generation and storage devices

    NASA Astrophysics Data System (ADS)

    Mills, Eric N.

    This dissertation encompasses the creation and testing of nanostructured, electrochemically-active energy generation and storage devices, and development of the associated fabrication techniques. The fabricated devices include nanopatterned, plasmonically-active, TiO2+Au thin films for Photocatalytic Water Splitting (PCW), TiO2-based Dye-Sensitized Solar Cells (DSSCs) incorporating nanopatterned, plasmonically-active metallic front electrodes, and Si nanopillar anodes for Li-ion batteries. Techniques were also developed for encapsulation and removal of wet-etched Si nanowires from their mother substrates. TiO2 was the first material to be widely used for PCW. Its use is hampered by its large bandgap (~3.2eV), and poor recombination lifetimes. Au nanoparticles (NPs) have been previously used to improve recombination lifetimes in TiO2 by separating photogenerated carriers near the NP edges, and to increase photocurrents by injecting plasmonically-excited hot electrons into the TiO2 conduction band. Using nanostructured TiO 2+Au electrodes, we aim to increase the PCW efficiency of TiO2 -based electrodes. Dye-sensitized solar cells (DSSCs) employ visible-absorbing dyes anchored to a high-surface-area semiconducting scaffold. The front transparent conducting electrode (TCE) is typically ITO, a scarce and expensive material. We aim to increase the efficiency of thin-film DSSCs and eliminate the use of ITO by using a metallic subwavelength array (MESH) of nanoholes as the front TCE. Silicon holds promise as a high-capacity anode material for Li-ion batteries, as it can store ~10x the Li of graphite, the current leading anode material (3569 vs. 372 mAh/g). However, Si undergoes dramatic (>300%) volume expansion upon "lithiation", pulverizing any structure with non-nanoscopic dimensions (>250nm). We created large-area arrays of "nanopillars" with sub-100nm diameters, using roll-to-roll-compatible flexible-mold NIL on commercially-available metal substrates. Ordered

  9. A Robust and Device-Free System for the Recognition and Classification of Elderly Activities

    PubMed Central

    Li, Fangmin; Al-qaness, Mohammed Abdulaziz Aide; Zhang, Yong; Zhao, Bihai; Luan, Xidao

    2016-01-01

    Human activity recognition, tracking and classification is an essential trend in assisted living systems that can help support elderly people with their daily activities. Traditional activity recognition approaches depend on vision-based or sensor-based techniques. Nowadays, a novel promising technique has obtained more attention, namely device-free human activity recognition that neither requires the target object to wear or carry a device nor install cameras in a perceived area. The device-free technique for activity recognition uses only the signals of common wireless local area network (WLAN) devices available everywhere. In this paper, we present a novel elderly activities recognition system by leveraging the fluctuation of the wireless signals caused by human motion. We present an efficient method to select the correct data from the Channel State Information (CSI) streams that were neglected in previous approaches. We apply a Principle Component Analysis method that exposes the useful information from raw CSI. Thereafter, Forest Decision (FD) is adopted to classify the proposed activities and has gained a high accuracy rate. Extensive experiments have been conducted in an indoor environment to test the feasibility of the proposed system with a total of five volunteer users. The evaluation shows that the proposed system is applicable and robust to electromagnetic noise. PMID:27916948

  10. Electronic security systems and active implantable medical devices.

    PubMed

    Irnich, Werner

    2002-08-01

    How do active implantable medical devices react in the presence of strong magnetic fields in the frequency range between extremely low frequency (ELF) to radiofrequency (RF) as they are emitted by electronic security systems (ESS)? There are three different sorts of ESSs: electronic article surveillance (EAS) devices, metal detector (MDS) devices, and radiofrequency identification (RFID) systems. Common to all is the production of magnetic fields. There is an abundance of literature concerning interference by ESS gates with respect to if there is an influence possible and if such an influence can bear a risk for the AIMD wearers. However, there has been no attempt to study the physical mechanism nor to develop a model of how and under which conditions magnetic fields can influence pacemakers and defibrillators and how they could be disarmed by technological means. It is too often assumed that interference of AIMD with ESS is inevitable. Exogenous signals of similar intensity and rhythm to heart signals can be misinterpreted and, thus, confuse the implant. Important for the interference coupling mechanism is the differentiation between a "unipolar" and a "bipolar" system. With respect to magnetic fields, the left side implanted pacemaker is the most unfavorable case as the lead forms approximately a semicircular area of maximum 225 cm2 into which a voltage can be induced. This assumption yields an interference coupling model that can be expressed by simple mathematics. The worst-case conditions for induced interference voltages are a coupling area of 225 cm2 that is representative for a large human, a homogeneous magnetic field perpendicular to the area formed by the lead, and a unipolar ventricular pacemaker system that is implanted on the left side of the thorax and has the highest interference sensitivity. In bipolar systems the fields must be 17 times larger when compared to a unipolar system to have the same effect. The magnetic field for interfering with ICDs

  11. Laser-activated shape memory polymer intravascular thrombectomy device

    NASA Astrophysics Data System (ADS)

    Small, Ward, IV; Wilson, Thomas S.; Benett, William J.; Loge, Jeffrey M.; Maitland, Duncan J.

    2005-10-01

    A blood clot (thrombus) that becomes lodged in the arterial network supplying the brain can cause an ischemic stroke, depriving the brain of oxygen and often resulting in permanent disability. As an alternative to conventional clot-dissolving drug treatment, we are developing an intravascular laser-activated therapeutic device using shape memory polymer (SMP) to mechanically retrieve the thrombus and restore blood flow to the brain. Thermal imaging and computer simulation were used to characterize the optical and photothermal behavior of the SMP microactuator. Deployment of the SMP device in an in vitro thrombotic vascular occlusion model demonstrated the clinical treatment concept.

  12. Electrochromic devices

    DOEpatents

    Allemand, Pierre M.; Grimes, Randall F.; Ingle, Andrew R.; Cronin, John P.; Kennedy, Steve R.; Agrawal, Anoop; Boulton, Jonathan M.

    2001-01-01

    An electrochromic device is disclosed having a selective ion transport layer which separates an electrochemically active material from an electrolyte containing a redox active material. The devices are particularly useful as large area architectural and automotive glazings due to there reduced back reaction.

  13. Holographic injection locking of a broad area laser diode via a photorefractive thin-film device.

    PubMed

    van Voorst, P D; de Wit, M R; Offerhaus, H L; Tay, S; Thomas, J; Peyghambarian, N; Boller, K-J

    2007-12-24

    We demonstrate locking of a high power broad area laser diode to a single frequency using holographic feedback from a photorefractive polymer thin-film device for the first time. A four-wave mixing setup is used to generate feedback for the broad area diode at the wavelength of the single frequency source (Ti:Sapphire laser) while the spatial distribution adapts to the preferred profile of the broad area diode. The result is an injection-locked broad area diode emitting with a linewidth comparable to the Ti:Sapphire laser.

  14. Large-area chromogenics: Materials and devices for transmittance control. Volume IS 4

    SciTech Connect

    Lampert, C.M.; Granqvist, C.G.

    1990-12-31

    Chromogenic materials can alter their optical properties in a persistent yet reversible manner when subjected to a change in external conditions such as irradiation intensity, temperature, or electric-field strength. In the future chromogenic materials may be used on large scale to regulate the throughput of radiant energy for windows in buildings and cars, so that comfortable lighting and temperature are maintained without excessive air conditioning. The purpose of this book is to give a broad coverage of large-area chromogenics and to discuss their applications. The book is divided into the following areas: applications; photochromic materials; thermochromic materials; inorganic electrochromic materials; inorganic electrochromic materials; organic electrochromic materials; conductors for ions and electrons in electrochromic devices; electrochromic devices; and liquid crystals materials and devices. Separate abstracts were prepared for 33 papers in this book.

  15. Multi-band terahertz active device with complementary metamaterial

    SciTech Connect

    Qiao, Shen; Zhang, Yaxin Sun, Linlin; Sun, Han; Xu, Gaiqi; Zhao, Yuncheng; Yang, Ziqiang; Liang, Shixiong

    2015-09-28

    We describe a multi-band terahertz-active device using a composite structure made of complementary metamaterial and doped silicon that can be dynamically controlled. This special complementary metamaterial exhibits three resonances that produce three pass-bands. The pass-bands can be uniformly manipulated by exploiting the photoinduced characteristics of the doped silicon. Simulations were performed to analyze the magnetic field and surface current distributions. The simulation results agree well with experimental results obtained from terahertz time-domain spectroscopy. Using an 808-nm-wavelength laser beam, a modulation depth of up to 80% was obtained. In numerical simulations, we used a conductivity mode to characterize photoinduction. The development of multi-band terahertz-active devices has many potential applications, for example, in filters, modulators, switches, and sensors.

  16. Wireless device for activation of an underground shock wave absorber

    NASA Astrophysics Data System (ADS)

    Chikhradze, M.; Akhvlediani, I.; Bochorishvili, N.; Mataradze, E.

    2011-10-01

    The paper describes the mechanism and design of the wireless device for activation of energy absorber for localization of blast energy in underground openings. The statistics shows that the greatest share of accidents with fatal results associate with explosions in coal mines due to aero-methane and/or air-coal media explosion. The other significant problem is terrorist or accidental explosions in underground structures. At present there are different protective systems to reduce the blast energy. One of the main parts of protective Systems is blast Identification and Registration Module. The works conducted at G. Tsulukidze Mining Institute of Georgia enabled to construct the wireless system of explosion detection and mitigation of shock waves. The system is based on the constant control on overpressure. The experimental research continues to fulfill the system based on both threats, on the constant control on overpressure and flame parameters, especially in underground structures and coal mines. Reaching the threshold value of any of those parameters, the system immediately starts the activation. The absorber contains a pyrotechnic device ensuring the discharge of dispersed water. The operational parameters of wireless device and activation mechanisms of pyrotechnic element of shock wave absorber are discussed in the paper.

  17. Ultrahigh Performance C60 Nanorod Large Area Flexible Photoconductor Devices via Ultralow Organic and Inorganic Photodoping

    PubMed Central

    Saran, Rinku; Stolojan, Vlad; Curry, Richard J.

    2014-01-01

    One dimensional single-crystal nanorods of C60 possess unique optoelectronic properties including high electron mobility, high photosensitivity and an excellent electron accepting nature. In addition, their rapid large scale synthesis at room temperature makes these organic semiconducting nanorods highly attractive for advanced optoelectronic device applications. Here, we report low-cost large-area flexible photoconductor devices fabricated using C60 nanorods. We demonstrate that the photosensitivity of the C60 nanorods can be enhanced ~400-fold via an ultralow photodoping mechanism. The photodoped devices offer broadband UV-vis-NIR spectral tuneability, exhibit a detectivitiy >109 Jones, an external quantum efficiency of ~100%, a linear dynamic range of 80 dB, a rise time 60 µs and the ability to measure ac signals up to ~250 kHz. These figures of merit combined are among the highest reported for one dimensional organic and inorganic large-area planar photoconductors and are competitive with commercially available inorganic photoconductors and photoconductive cells. With the additional processing benefits providing compatibility with large-area flexible platforms, these devices represent significant advances and make C60 nanorods a promising candidate for advanced photodetector technologies. PMID:24853479

  18. Localization of individual area neuronal activity.

    PubMed

    Hironaga, N; Ioannides, A A

    2007-02-15

    A family of methods, collectively known as independent component analysis (ICA), has recently been added to the array of methods designed to decompose a multi-channel signal into components. ICA methods have been applied to raw magnetoencephalography (MEG) and electroencephalography (EEG) signals to remove artifacts, especially when sources such as power line or cardiac activity generate strong components that dominate the signal. More recently, successful ICA extraction of stimulus-evoked responses has been reported from single-trial raw MEG and EEG signals. The extraction of weak components has often been erratic, depending on which ICA method is employed and even on what parameters are used. In this work, we show that if the emphasis is placed on individual "independent components," as is usually the case with standard ICA applications, differences in the results obtained for different components are exaggerated. We propose instead the reconstruction of regional brain activations by combining tomographic estimates of individual independent components that have been selected by appropriate spatial and temporal criteria. Such localization of individual area neuronal activity (LIANA) allows reliable semi-automatic extraction of single-trial regional activations from raw MEG data. We demonstrate the new method with three different ICA algorithms applied to both computer-generated signals and real data. We show that LIANA provides almost identical results with each ICA method despite the fact that each method yields different individual components.

  19. Demixing Population Activity in Higher Cortical Areas

    PubMed Central

    Machens, Christian K.

    2009-01-01

    Neural responses in higher cortical areas often display a baffling complexity. In animals performing behavioral tasks, single neurons will typically encode several parameters simultaneously, such as stimuli, rewards, decisions, etc. When dealing with this large heterogeneity of responses, cells are conventionally classified into separate response categories using various statistical tools. However, this classical approach usually fails to account for the distributed nature of representations in higher cortical areas. Alternatively, principal component analysis (PCA) or related techniques can be employed to reduce the complexity of a data set while retaining the distributional aspect of the population activity. These methods, however, fail to explicitly extract the task parameters from the neural responses. Here we suggest a coordinate transformation that seeks to ameliorate these problems by combining the advantages of both methods. Our basic insight is that variance in neural firing rates can have different origins (such as changes in a stimulus, a reward, or the passage of time), and that, instead of lumping them together, as PCA does, we need to treat these sources separately. We present a method that seeks an orthogonal coordinate transformation such that the variance captured from different sources falls into orthogonal subspaces and is maximized within these subspaces. Using simulated examples, we show how this approach can be used to demix heterogeneous neural responses. Our method may help to lift the fog of response heterogeneity in higher cortical areas. PMID:21031029

  20. Large-area nanofabrication and applications in advanced nanoelectronic and nanophotonic devices

    NASA Astrophysics Data System (ADS)

    Ding, Wei

    The research work presented in this dissertation includes novel large area nanofabrication techniques and their applications in advanced nanoelectronic and nanophotonic devices. The fabrications and applications include: 1) high performance transparent electrodes, 2) a novel plasmonic nanocavity and its applications in organic solar cells and light emitting diodes, and 3) a bipolar plasmonic nonlinear optical device to enhance and tune second harmonic generation. Based upon these topics, the thesis is divided into the following parts. First, a novel transparent electrode (TE), metallic deep subwavelength mesh electrode is developed and fabricated, showing better transmittance and conductance than previous TEs. Its performance dependence on nanostructure geometries and materials are investigated. The deep-subwavelength mesh electrode also has excellent antiglare properties. Such electrodes are fabricated on 4" wafer by nanoimprint, scalable to meter sizes. Second, a novel plasmonic nanocavity from the MESH is developed, named "plasmonic cavity with subwavelength hole-array (PlaCSH)", consisting of a thin MESH as a transparent front electrode, a thin metal back electrode, and in-between layer of active material. This structure is used to create high performance solar cells and LEDs. PlaCSH solar cell gives a solution to three central challenges in organic solar cells (light coupling into solar cell, light trapping in a sub-absorption-length-thick layer, and replacement of the indium-tin-oxide). Experimentally, the PlaCSH polymer SCs achieve high light coupling-efficiency/absorptance/power conversion efficiency, along with broad-band, Omni angle/polarization acceptance. In OLEDs, PlaCSH shows numerous benefits with both the small- molecule and polymer active materials. Enhanced light extraction, internal quantum efficiency, ambient light absorption, contrast, viewing angle, brightness, and decreased glare are all observed. The above experiments -- along with

  1. Light-induced self-assembly of active rectification devices.

    PubMed

    Stenhammar, Joakim; Wittkowski, Raphael; Marenduzzo, Davide; Cates, Michael E

    2016-04-01

    Self-propelled colloidal objects, such as motile bacteria or synthetic microswimmers, have microscopically irreversible individual dynamics-a feature they share with all living systems. The incoherent behavior of individual swimmers can be harnessed (or "rectified") by microfluidic devices that create systematic motions that are impossible in equilibrium. We present a computational proof-of-concept study showing that such active rectification devices could be created directly from an unstructured "primordial soup" of light-controlled motile particles, solely by using spatially modulated illumination to control their local propulsion speed. Alongside both microscopic irreversibility and speed modulation, our mechanism requires spatial symmetry breaking, such as a chevron light pattern, and strong interactions between particles, such as volume exclusion, which cause a collisional slowdown at high density. Together, we show how these four factors create a novel, many-body rectification mechanism. Our work suggests that standard spatial light modulator technology might allow the programmable, light-induced self-assembly of active rectification devices from an unstructured particle bath.

  2. A microfluidic paper-based device to assess acetylcholinesterase activity.

    PubMed

    Liu, Chunye; Gomez, Frank A

    2017-04-01

    Neurotransmitters play key roles in cell-to-cell communication. These chemical messengers are involved in many functional processes, including growth, reproduction, memory, and behavior. In this communication, we describe a novel microfluidic paper-based analytical device (μPAD) to detect acetylcholinesterase (AChE) activity and inhibitor screening through a colorimetric analysis. The μPAD is easily fabricated via a wax printing process whereby wax is deposited onto the surface of chromatographic paper, and heated to create a hydrophobic barrier. Separate solutions of 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) and samples containing AChE and acetylthiocholine iodide (ATC) (or cysteine, Cys), respectively, are directly spotted onto the μPAD. DTNB and AChE/ATC (or Cys) flow towards each other where a reaction occurs to form the yellow colored 2-nitro-5-thiobenzoic acid anion (TNB(2-) ). The device is dried, scanned, and analyzed yielding a linear range of average inverse yellow intensities versus substrate concentration. An IC50 value (0.045 nM) with a known inhibitor, neostigmine bromide (NB), is obtained on the device. μPADs are low cost and easy to fabricate and have great potential to quantify neurotransmitter activity.

  3. Light-induced self-assembly of active rectification devices

    PubMed Central

    Stenhammar, Joakim; Wittkowski, Raphael; Marenduzzo, Davide; Cates, Michael E.

    2016-01-01

    Self-propelled colloidal objects, such as motile bacteria or synthetic microswimmers, have microscopically irreversible individual dynamics—a feature they share with all living systems. The incoherent behavior of individual swimmers can be harnessed (or “rectified”) by microfluidic devices that create systematic motions that are impossible in equilibrium. We present a computational proof-of-concept study showing that such active rectification devices could be created directly from an unstructured “primordial soup” of light-controlled motile particles, solely by using spatially modulated illumination to control their local propulsion speed. Alongside both microscopic irreversibility and speed modulation, our mechanism requires spatial symmetry breaking, such as a chevron light pattern, and strong interactions between particles, such as volume exclusion, which cause a collisional slowdown at high density. Together, we show how these four factors create a novel, many-body rectification mechanism. Our work suggests that standard spatial light modulator technology might allow the programmable, light-induced self-assembly of active rectification devices from an unstructured particle bath. PMID:27051883

  4. Toxin activity assays, devices, methods and systems therefor

    DOEpatents

    Koh, Chung-Yan; Schaff, Ulrich Y.; Sommer, Gregory Jon

    2016-04-05

    Embodiments of the present invention are directed toward devices, system and method for conducting toxin activity assay using sedimentation. The toxin activity assay may include generating complexes which bind to a plurality of beads in a fluid sample. The complexes may include a target toxin and a labeling agent, or may be generated due to presence of active target toxin and/or labeling agent designed to be incorporated into complexes responsive to the presence of target active toxin. The plurality of beads including the complexes may be transported through a density media, wherein the density media has a lower density than a density of the beads and higher than a density of the fluid sample, and wherein the transporting occurs, at least in part, by sedimentation. Signal may be detected from the labeling agents of the complexes.

  5. Integration of active devices on smart polymers for neural interfaces

    NASA Astrophysics Data System (ADS)

    Avendano-Bolivar, Adrian Emmanuel

    The increasing ability to ever more precisely identify and measure neural interactions and other phenomena in the central and peripheral nervous systems is revolutionizing our understanding of the human body and brain. To facilitate further understanding, more sophisticated neural devices, perhaps using microelectronics processing, must be fabricated. Materials often used in these neural interfaces, while compatible with these fabrication processes, are not optimized for long-term use in the body and are often orders of magnitude stiffer than the tissue with which they interact. Using the smart polymer substrates described in this work, suitability for processing as well as chronic implantation is demonstrated. We explore how to integrate reliable circuitry onto these flexible, biocompatible substrates that can withstand the aggressive environment of the body. To increase the capabilities of these devices beyond individual channel sensing and stimulation, active electronics must also be included onto our systems. In order to add this functionality to these substrates and explore the limits of these devices, we developed a process to fabricate single organic thin film transistors with mobilities up to 0.4 cm2/Vs and threshold voltages close to 0V. A process for fabricating organic light emitting diodes on flexible substrates is also addressed. We have set a foundation and demonstrated initial feasibility for integrating multiple transistors onto thin-film flexible devices to create new applications, such as matrix addressable functionalized electrodes and organic light emitting diodes. A brief description on how to integrate waveguides for their use in optogenetics is addressed. We have built understanding about device constraints on mechanical, electrical and in vivo reliability and how various conditions affect the electronics' lifetime. We use a bi-layer gate dielectric using an inorganic material such as HfO 2 combined with organic Parylene-c. A study of

  6. The Use of Multiple Slate Devices to Support Active Reading Activities

    ERIC Educational Resources Information Center

    Chen, Nicholas Yen-Cherng

    2012-01-01

    Reading activities in the classroom and workplace occur predominantly on paper. Since existing electronic devices do not support these reading activities as well as paper, users have difficulty taking full advantage of the affordances of electronic documents. This dissertation makes three main contributions toward supporting active reading…

  7. Synthesis of Large Area Graphene for High Performance in Flexible Optoelectronic Devices

    PubMed Central

    Polat, Emre O.; Balci, Osman; Kakenov, Nurbek; Uzlu, Hasan Burkay; Kocabas, Coskun; Dahiya, Ravinder

    2015-01-01

    This work demonstrates an attractive low-cost route to obtain large area and high-quality graphene films by using the ultra-smooth copper foils which are typically used as the negative electrodes in lithium-ion batteries. We first compared the electronic transport properties of our new graphene film with the one synthesized by using commonly used standard copper foils in chemical vapor deposition (CVD). We observed a stark improvement in the electrical performance of the transistors realized on our graphene films. To study the optical properties on large area, we transferred CVD based graphene to transparent flexible substrates using hot lamination method and performed large area optical scanning. We demonstrate the promise of our high quality graphene films for large areas with ~400 cm2 flexible optical modulators. We obtained a profound light modulation over a broad spectrum by using the fabricated large area transparent graphene supercapacitors and we compared the performance of our devices with the one based on graphene from standard copper. We propose that the copper foils used in the lithium-ion batteries could be used to obtain high-quality graphene at much lower-cost, with the improved performance of electrical transport and optical properties in the devices made from them. PMID:26578425

  8. Active control of excessive sound emission on a mobile device.

    PubMed

    Jeon, Se-Woon; Youn, Dae Hee; Park, Young-cheol; Lee, Gun-Woo

    2015-04-01

    During a phone conversation, loud vocal emission from the far-end to the near-end space can disturb nearby people. In this paper, the possibility of actively controlling such unwanted sound emission using a control source placed on the mobile device is investigated. Two different approaches are tested: Global control, minimizing the potential energy measured along a volumetric space surface, and local control, minimizing the squared sound pressure at a discrete point on the phone. From the test results, both approaches can reduce the unwanted sound emission by more than 6 dB in the frequency range up to 2 kHz.

  9. Device for measuring oxygen activity in liquid sodium

    DOEpatents

    Roy, P.; Young, R.S.

    1973-12-01

    A composite ceramic electrolyte in a configuration (such as a closed end tube or a plate) suitable to separate liquid sodium from a reference electrode with a high impedance voltmeter connected to measure EMF between the sodium and the reference electrode as a measure of oxygen activity in the sodium is described. The composite electrolyte consists of zirconiacalcia with a bonded layer of thoria-yttria. The device is used with a gaseous reference electrode on the zirconia-calcia side and liquid sodium on the thoria-yttria side of the electrolyte. (Official Gazette)

  10. Infrared micro-thermography of an actively heated preconcentrator device

    NASA Astrophysics Data System (ADS)

    Furstenberg, Robert; Kendziora, C. A.; Stepnowski, Stanley V.; Mott, David R.; McGill, R. Andrew

    2008-03-01

    We report infrared micro-thermography measurements and analysis of static and transient temperature maps of an actively heated micro-fabricated preconcentrator device that incorporates a dual serpentine platinum heater trace deposited on a perforated polyimide membrane and suspended over a silicon frame. The sorbent coated perforated membrane is used to collect vapors and gases that flow through the preconcentrator. After heating, a concentrated pulse of analyte is released into the detector. Due to its small thermal mass, precise thermal management of the preconcentrator is critical to its performance. The sizes of features, the semi-transparent membrane, the need to flow air through the device, and changes in surface emissivity on a micron scale present many challenges for traditional infrared micro-thermography. We report an improved experimental test-bed. The hardware incorporates a custom-designed miniature calibration oven which, in conjunction with spatial filtering and a simple calibration algorithm, allows accurate temperature maps to be obtained. The test-bed incorporates a micro-bolometer array as the infrared imager. Instrumentation design, calibration and image processing algorithms are discussed and analyzed. The procedure does not require prior knowledge of the emissivity. We show that relatively inexpensive uncooled bolometers arrays can be used in certain radiometric applications. Heating profiles were examined with both uniform and non-uniform air flow through the device. The conclusions from this study provide critical information for optimal integration of the preconcentrator within a detection system, and in the design of the heater trace layout to achieve a more even temperature distribution across the device.

  11. Ultra-Smooth, Fully Solution-Processed Large-Area Transparent Conducting Electrodes for Organic Devices

    PubMed Central

    Jin, Won-Yong; Ginting, Riski Titian; Ko, Keum-Jin; Kang, Jae-Wook

    2016-01-01

    A novel approach for the fabrication of ultra-smooth and highly bendable substrates consisting of metal grid-conducting polymers that are fully embedded into transparent substrates (ME-TCEs) was successfully demonstrated. The fully printed ME-TCEs exhibited ultra-smooth surfaces (surface roughness ~1.0 nm), were highly transparent (~90% transmittance at a wavelength of 550 nm), highly conductive (sheet resistance ~4 Ω ◻−1), and relatively stable under ambient air (retaining ~96% initial resistance up to 30 days). The ME-TCE substrates were used to fabricate flexible organic solar cells and organic light-emitting diodes exhibiting devices efficiencies comparable to devices fabricated on ITO/glass substrates. Additionally, the flexibility of the organic devices did not degrade their performance even after being bent to a bending radius of ~1 mm. Our findings suggest that ME-TCEs are a promising alternative to indium tin oxide and show potential for application toward large-area optoelectronic devices via fully printing processes. PMID:27808221

  12. Ultra-Smooth, Fully Solution-Processed Large-Area Transparent Conducting Electrodes for Organic Devices

    NASA Astrophysics Data System (ADS)

    Jin, Won-Yong; Ginting, Riski Titian; Ko, Keum-Jin; Kang, Jae-Wook

    2016-11-01

    A novel approach for the fabrication of ultra-smooth and highly bendable substrates consisting of metal grid-conducting polymers that are fully embedded into transparent substrates (ME-TCEs) was successfully demonstrated. The fully printed ME-TCEs exhibited ultra-smooth surfaces (surface roughness ~1.0 nm), were highly transparent (~90% transmittance at a wavelength of 550 nm), highly conductive (sheet resistance ~4 Ω ◻‑1), and relatively stable under ambient air (retaining ~96% initial resistance up to 30 days). The ME-TCE substrates were used to fabricate flexible organic solar cells and organic light-emitting diodes exhibiting devices efficiencies comparable to devices fabricated on ITO/glass substrates. Additionally, the flexibility of the organic devices did not degrade their performance even after being bent to a bending radius of ~1 mm. Our findings suggest that ME-TCEs are a promising alternative to indium tin oxide and show potential for application toward large-area optoelectronic devices via fully printing processes.

  13. Ultra-Smooth, Fully Solution-Processed Large-Area Transparent Conducting Electrodes for Organic Devices.

    PubMed

    Jin, Won-Yong; Ginting, Riski Titian; Ko, Keum-Jin; Kang, Jae-Wook

    2016-11-03

    A novel approach for the fabrication of ultra-smooth and highly bendable substrates consisting of metal grid-conducting polymers that are fully embedded into transparent substrates (ME-TCEs) was successfully demonstrated. The fully printed ME-TCEs exhibited ultra-smooth surfaces (surface roughness ~1.0 nm), were highly transparent (~90% transmittance at a wavelength of 550 nm), highly conductive (sheet resistance ~4 Ω ◻(-1)), and relatively stable under ambient air (retaining ~96% initial resistance up to 30 days). The ME-TCE substrates were used to fabricate flexible organic solar cells and organic light-emitting diodes exhibiting devices efficiencies comparable to devices fabricated on ITO/glass substrates. Additionally, the flexibility of the organic devices did not degrade their performance even after being bent to a bending radius of ~1 mm. Our findings suggest that ME-TCEs are a promising alternative to indium tin oxide and show potential for application toward large-area optoelectronic devices via fully printing processes.

  14. Inferring Human Activity in Mobile Devices by Computing Multiple Contexts.

    PubMed

    Chen, Ruizhi; Chu, Tianxing; Liu, Keqiang; Liu, Jingbin; Chen, Yuwei

    2015-08-28

    This paper introduces a framework for inferring human activities in mobile devices by computing spatial contexts, temporal contexts, spatiotemporal contexts, and user contexts. A spatial context is a significant location that is defined as a geofence, which can be a node associated with a circle, or a polygon; a temporal context contains time-related information that can be e.g., a local time tag, a time difference between geographical locations, or a timespan; a spatiotemporal context is defined as a dwelling length at a particular spatial context; and a user context includes user-related information that can be the user's mobility contexts, environmental contexts, psychological contexts or social contexts. Using the measurements of the built-in sensors and radio signals in mobile devices, we can snapshot a contextual tuple for every second including aforementioned contexts. Giving a contextual tuple, the framework evaluates the posteriori probability of each candidate activity in real-time using a Naïve Bayes classifier. A large dataset containing 710,436 contextual tuples has been recorded for one week from an experiment carried out at Texas A&M University Corpus Christi with three participants. The test results demonstrate that the multi-context solution significantly outperforms the spatial-context-only solution. A classification accuracy of 61.7% is achieved for the spatial-context-only solution, while 88.8% is achieved for the multi-context solution.

  15. Inferring Human Activity in Mobile Devices by Computing Multiple Contexts

    PubMed Central

    Chen, Ruizhi; Chu, Tianxing; Liu, Keqiang; Liu, Jingbin; Chen, Yuwei

    2015-01-01

    This paper introduces a framework for inferring human activities in mobile devices by computing spatial contexts, temporal contexts, spatiotemporal contexts, and user contexts. A spatial context is a significant location that is defined as a geofence, which can be a node associated with a circle, or a polygon; a temporal context contains time-related information that can be e.g., a local time tag, a time difference between geographical locations, or a timespan; a spatiotemporal context is defined as a dwelling length at a particular spatial context; and a user context includes user-related information that can be the user’s mobility contexts, environmental contexts, psychological contexts or social contexts. Using the measurements of the built-in sensors and radio signals in mobile devices, we can snapshot a contextual tuple for every second including aforementioned contexts. Giving a contextual tuple, the framework evaluates the posteriori probability of each candidate activity in real-time using a Naïve Bayes classifier. A large dataset containing 710,436 contextual tuples has been recorded for one week from an experiment carried out at Texas A&M University Corpus Christi with three participants. The test results demonstrate that the multi-context solution significantly outperforms the spatial-context-only solution. A classification accuracy of 61.7% is achieved for the spatial-context-only solution, while 88.8% is achieved for the multi-context solution. PMID:26343665

  16. Method and apparatus for actively controlling a micro-scale flexural plate wave device

    DOEpatents

    Dohner, Jeffrey L.

    2001-01-01

    An actively controlled flexural plate wave device provides a micro-scale pump. A method of actively controlling a flexural plate wave device produces traveling waves in the device by coordinating the interaction of a magnetic field with actively controlled currents. An actively-controlled flexural plate wave device can be placed in a fluid channel and adapted for use as a micro-scale fluid pump to cool or drive micro-scale systems, for example, micro-chips, micro-electrical-mechanical devices, micro-fluid circuits, or micro-scale chemical analysis devices.

  17. Upscaling of integrated photoelectrochemical water-splitting devices to large areas

    PubMed Central

    Turan, Bugra; Becker, Jan-Philipp; Urbain, Félix; Finger, Friedhelm; Rau, Uwe; Haas, Stefan

    2016-01-01

    Photoelectrochemical water splitting promises both sustainable energy generation and energy storage in the form of hydrogen. However, the realization of this vision requires laboratory experiments to be engineered into a large-scale technology. Up to now only few concepts for scalable devices have been proposed or realized. Here we introduce and realize a concept which, by design, is scalable to large areas and is compatible with multiple thin-film photovoltaic technologies. The scalability is achieved by continuous repetition of a base unit created by laser processing. The concept allows for independent optimization of photovoltaic and electrochemical part. We demonstrate a fully integrated, wireless device with stable and bias-free operation for 40 h. Furthermore, the concept is scaled to a device area of 64 cm2 comprising 13 base units exhibiting a solar-to-hydrogen efficiency of 3.9%. The concept and its successful realization may be an important contribution towards the large-scale application of artificial photosynthesis. PMID:27601181

  18. Upscaling of integrated photoelectrochemical water-splitting devices to large areas

    NASA Astrophysics Data System (ADS)

    Turan, Bugra; Becker, Jan-Philipp; Urbain, Félix; Finger, Friedhelm; Rau, Uwe; Haas, Stefan

    2016-09-01

    Photoelectrochemical water splitting promises both sustainable energy generation and energy storage in the form of hydrogen. However, the realization of this vision requires laboratory experiments to be engineered into a large-scale technology. Up to now only few concepts for scalable devices have been proposed or realized. Here we introduce and realize a concept which, by design, is scalable to large areas and is compatible with multiple thin-film photovoltaic technologies. The scalability is achieved by continuous repetition of a base unit created by laser processing. The concept allows for independent optimization of photovoltaic and electrochemical part. We demonstrate a fully integrated, wireless device with stable and bias-free operation for 40 h. Furthermore, the concept is scaled to a device area of 64 cm2 comprising 13 base units exhibiting a solar-to-hydrogen efficiency of 3.9%. The concept and its successful realization may be an important contribution towards the large-scale application of artificial photosynthesis.

  19. A Novel Wearable Device for Food Intake and Physical Activity Recognition

    PubMed Central

    Farooq, Muhammad; Sazonov, Edward

    2016-01-01

    Presence of speech and motion artifacts has been shown to impact the performance of wearable sensor systems used for automatic detection of food intake. This work presents a novel wearable device which can detect food intake even when the user is physically active and/or talking. The device consists of a piezoelectric strain sensor placed on the temporalis muscle, an accelerometer, and a data acquisition module connected to the temple of eyeglasses. Data from 10 participants was collected while they performed activities including quiet sitting, talking, eating while sitting, eating while walking, and walking. Piezoelectric strain sensor and accelerometer signals were divided into non-overlapping epochs of 3 s; four features were computed for each signal. To differentiate between eating and not eating, as well as between sedentary postures and physical activity, two multiclass classification approaches are presented. The first approach used a single classifier with sensor fusion and the second approach used two-stage classification. The best results were achieved when two separate linear support vector machine (SVM) classifiers were trained for food intake and activity detection, and their results were combined using a decision tree (two-stage classification) to determine the final class. This approach resulted in an average F1-score of 99.85% and area under the curve (AUC) of 0.99 for multiclass classification. With its ability to differentiate between food intake and activity level, this device may potentially be used for tracking both energy intake and energy expenditure. PMID:27409622

  20. PARduino: A Simple Device Measuring and Logging Photosynthetically Active Radiation

    NASA Astrophysics Data System (ADS)

    Barnard, H. R.; Findley, M. C.

    2013-12-01

    Photosynthetically Active Radiation (PAR, 400 to 700 nm) is one of the primary controls of forest carbon and water relations. In complex terrain, PAR has high spatial-variability. Given the high cost of commercial datalogging equipment, spatially-distributed measurements of PAR have been typically modeled using geographic coordinates and terrain indices. Here, we present a design for a low cost, field-deployable device for measuring and logging PAR built around an Arduino microcontroller (we named it PARduino). PARduino provides for widely distributed sensor arrays and tests the feasibility of using hobbyist-grade electronics for collecting scientific data. PARduino components include a LiCor quantum sensor, EME Systems signal converter/amplifier, and Sparkfun's Arduino Pro Mini microcontroller. Additional components include a real time clock, a microSD flash memory card, and a custom printed circuit board (PCB). We selected the components with an eye towards ease of assembly. Everything can be connected to the PCB using through-hole soldering techniques. Since the device will be deployed in remote research plots that lack easy access to line power, battery life was also a consideration in the design. Extended deployment is possible because PARduino's software keeps it in a low-power sleep mode until ready to make a measurement. PARduino will be open-source hardware for use and improvement by others.

  1. Measurement of active shoulder proprioception: dedicated system and device.

    PubMed

    Lubiatowski, Przemyslaw; Ogrodowicz, Piotr; Wojtaszek, Marcin; Kaniewski, Ryszard; Stefaniak, Jakub; Dudziński, Witold; Romanowski, Leszek

    2013-02-01

    Proprioception is an essential part of shoulder stability and neuromuscular control. The purpose of the study was the development of a precise system of shoulder proprioception assessment in the active mode (Propriometr). For that purpose, devices such as the electronic goniometer and computer software had been designed. A pilot study was carried out on a control group of 27 healthy subjects, the average age being 23.8 (22-29) in order to test the system. The result of the assessment was the finding of the error of active reproduction of the joint position (EARJP). EARJP was assessed for flexion, abduction, external and internal rotation. For every motion, reference positions were used at three different angles. The results showed EARJP to range in 3-6.1°. The proprioception evaluation system (propriometr) allows a precise measurement of active joint position sense. The designed system can be used to assess proprioception in both shoulder injuries and treatment. In addition, all achieved results of normal shoulders may serve as reference to be compared with the results of forthcoming studies.

  2. Ultrasonic probe deployment device for increased wave transmission and rapid area scan inspections

    DOEpatents

    DiMambro, Joseph [Placitas, NM; Roach, Dennis P [Albuquerque, NM; Rackow, Kirk A [Albuquerque, NM; Nelson, Ciji L [Albuquerque, NM; Dasch, Cameron J [Boomfield Hills, MI; Moore, David G [Albuquerque, NM

    2012-01-03

    An ultrasonic probe deployment device in which an ultrasound-transmitting liquid forms the portion of the ultrasonic wave path in contact with the surface being inspected (i.e., the inspection surface). A seal constrains flow of the liquid, for example preventing the liquid from surging out and flooding the inspection surface. The seal is not rigid and conforms to variations in the shape and unevenness of the inspection surface, thus forming a seal (although possibly a leaky seal) around the liquid. The probe preferably is held in place to produce optimum ultrasonic focus on the area of interest. Use of encoders can facilitate the production of C-scan area maps of the material being inspected.

  3. Ultrasonic probe deployment device for increased wave transmission and rapid area scan inspections

    DOEpatents

    DiMambro, Joseph; Roach, Dennis P; Rackow, Kirk A; Nelson, Ciji L; Dasch, Cameron J; Moore, David G

    2013-02-12

    An ultrasonic probe deployment device in which an ultrasound-transmitting liquid forms the portion of the ultrasonic wave path in contact with the surface being inspected (i.e., the inspection surface). A seal constrains flow of the liquid, for example preventing the liquid from surging out and flooding the inspection surface. The seal is not rigid and conforms to variations in the shape and unevenness of the inspection surface, thus forming a seal (although possibly a leaky seal) around the liquid. The probe preferably is held in place to produce optimum ultrasonic focus on the area of interest. Use of encoders can facilitate the production of C-scan area maps of the material being inspected.

  4. Controlled growth of larger heterojunction interface area for organic photosensitive devices

    DOEpatents

    Yang, Fan; Forrest, Stephen R.

    2009-12-29

    An optoelectronic device and a method of fabricating a photosensitive optoelectronic device includes depositing a first organic semiconductor material on a first electrode to form a continuous first layer having protrusions, a side of the first layer opposite the first electrode having a surface area at least three times greater than an underlying lateral cross-sectional area; depositing a second organic semiconductor material directly on the first layer to form a discontinuous second layer, portions of the first layer remaining exposed; depositing a third organic semiconductor material directly on the second layer to form a discontinuous third layer, portions of at least the second layer remaining exposed; depositing a fourth organic semiconductor material on the third layer to form a continuous fourth layer, filling any exposed gaps and recesses in the first, second, and third layers; and depositing a second electrode on the fourth layer, wherein at least one of the first electrode and the second electrode is transparent, and the first and third organic semiconductor materials are both of a donor-type or an acceptor-type relative to second and fourth organic semiconductor materials, which are of the other material type.

  5. Physical and electrochemical analysis of an indoor-outdoor ageing test of large-area dye solar cell devices.

    PubMed

    Mastroianni, Simone; Lanuti, Alessandro; Penna, Stefano; Reale, Andrea; Brown, Thomas M; Di Carlo, Aldo; Decker, Franco

    2012-08-27

    A long-term life test (3200 h) on large-area dye-sensitized cells is performed both under outdoor conditions, in the sunny Mediterranean climate in Rome (Italy), and under continuous light soaking (1 Sun, 85 °C). Different degradation rates are investigated for the outdoor samples with horizontally and vertically oriented cells (azimuth South, tilt angle 25°). Thirty identical photocells (active area=3.6 cm(2), conversion efficiencies=(4.8±0.2)%) are aged using a robust master-plate configuration. After the first 1000 h of testing in open-circuit conditions, some of the test samples are set near the maximum power point (MPP) and the life test continued further until 3200 h. A detailed analysis of the physical parameters obtained by electrochemical impedance is given together with electrolyte transmittance variation with time as a function of the ageing conditions. Faster degradation in devices working at the MPP is observed, due mainly to a progressive decrease of the triiodide concentration in the electrolyte and a likely alteration at the titania/electrolyte interface. Outdoor devices working with vertically oriented cells show clearly that the orientation of long-striped cells can affect the lifetime. The aged cells suffer an increase of recombination rate, change in the chemical capacitance, and positive shift of the titania conduction band level. A strong correlation between the increase of the electrolyte diffusion resistance and degradation phenomena is found.

  6. Field-induced activation of metal oxide semiconductor for low temperature flexible transparent electronic device applications

    NASA Astrophysics Data System (ADS)

    Pudasaini, Pushpa Raj; Noh, Joo Hyon; Wong, Anthony; Haglund, Amada; Ward, Thomas Zac; Mandrus, David; Rack, Philip

    Amorphous metal-oxide semiconductors have been extensively studied as an active channel material in thin film transistors due to their high carrier mobility, and excellent large-area uniformity. Here, we report the athermal activation of amorphous indium gallium zinc oxide semiconductor channels by an electric field-induced oxygen migration via gating through an ionic liquid. Using field-induced activation, a transparent flexible thin film transistor is demonstrated on a polyamide substrate with transistor characteristics having a current ON-OFF ratio exceeding 108, and saturation field effect mobility of 8.32 cm2/(V.s) without a post-deposition thermal treatment. This study demonstrates the potential of field-induced activation as an athermal alternative to traditional post-deposition thermal annealing for metal oxide electronic devices suitable for transparent and flexible polymer substrates. Materials Science and Technology Division, ORBL, Oak Ridge, TN 37831, USA.

  7. NASA's Spaceliner 100 Investment Area Technology Activities

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe; Lyles, Garry M. (Technical Monitor)

    2001-01-01

    NASA's has established long term goals for access-to-space. The third generation launch systems are to be fully reusable and operational around 2025. The goals for the third generation launch system are to reduce cost by a factor of 100 and improve safety by a factor of 10,000 over current conditions. The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center in Huntsville, AL has the agency lead to develop space transportation technologies. Within ASTP, under the Spaceliner100 Investment Area, third generation technologies are being pursued in the areas of propulsion, airframes, integrated vehicle health management (IVHM), launch systems, and operations and range. The ASTP program will mature these technologies through ground system testing. Flight testing where required, will be advocated on a case by case basis.

  8. NASA's Spaceliner Investment Area Technology Activities

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe; Lyles, Garry M. (Technical Monitor)

    2001-01-01

    NASA's has established long term goals for access-to-space. The third generation launch systems are to be fully reusable and operational around 2025. The goals for the third generation launch system are to significantly reduce cost and improve safety over current conditions. The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center in Huntsville, AL has the agency lead to develop space transportation technologies. Within ASTP, under the Spaceliner Investment Area, third generation technologies are being pursued in the areas of propulsion, airframes, integrated vehicle health management (IVHM), avionics, power, operations, and range. The ASTP program will mature these technologies through both ground and flight system testing. The Spaceliner Investment Area plans to mature vehicle technologies to reduce the implementation risks for future commercially developed reusable launch vehicles (RLV). The plan is to substantially increase the design and operating margins of the third generation RLV (the Space Shuttle is the first generation) by incorporating advanced technologies in propulsion, materials, structures, thermal protection systems, avionics, and power. Advancements in design tools and better characterization of the operational environment will allow improvements in design margins. Improvements in operational efficiencies will be provided through use of advanced integrated health management, operations, and range technologies. The increase in margins will allow components to operate well below their design points resulting in improved component operating life, reliability, and safety which in turn reduces both maintenance and refurbishment costs. These technologies have the potential of enabling horizontal takeoff by reducing the takeoff weight and achieving the goal of airline-like operation. These factors in conjunction with increased flight rates from an expanding market will result in significant improvements in safety

  9. Ionic Liquid Activation of Amorphous Metal-Oxide Semiconductors for Flexible Transparent Electronic Devices

    DOE PAGES

    Pudasaini, Pushpa Raj; Noh, Joo Hyon; Wong, Anthony T.; ...

    2016-02-09

    To begin this abstract, amorphous metal-oxide semiconductors offer the high carrier mobilities and excellent large-area uniformity required for high performance, transparent, flexible electronic devices; however, a critical bottleneck to their widespread implementation is the need to activate these materials at high temperatures which are not compatible with flexible polymer substrates. The highly controllable activation of amorphous indium gallium zinc oxide semiconductor channels using ionic liquid gating at room temperature is reported. Activation is controlled by electric field-induced oxygen migration across the ionic liquid-semiconductor interface. In addition to activation of unannealed devices, it is shown that threshold voltages of a transistormore » can be linearly tuned between the enhancement and depletion modes. Finally, the first ever example of transparent flexible thin film metal oxide transistor on a polyamide substrate created using this simple technique is demonstrated. Finally, this study demonstrates the potential of field-induced activation as a promising alternative to traditional postdeposition thermal annealing which opens the door to wide scale implementation into flexible electronic applications.« less

  10. Ionic Liquid Activation of Amorphous Metal-Oxide Semiconductors for Flexible Transparent Electronic Devices

    SciTech Connect

    Pudasaini, Pushpa Raj; Noh, Joo Hyon; Wong, Anthony T.; Ovchinnikova, Olga S.; Haglund, Amanda V.; Dai, Sheng; Ward, Thomas Zac; Mandrus, David; Rack, Philip D.

    2016-02-09

    To begin this abstract, amorphous metal-oxide semiconductors offer the high carrier mobilities and excellent large-area uniformity required for high performance, transparent, flexible electronic devices; however, a critical bottleneck to their widespread implementation is the need to activate these materials at high temperatures which are not compatible with flexible polymer substrates. The highly controllable activation of amorphous indium gallium zinc oxide semiconductor channels using ionic liquid gating at room temperature is reported. Activation is controlled by electric field-induced oxygen migration across the ionic liquid-semiconductor interface. In addition to activation of unannealed devices, it is shown that threshold voltages of a transistor can be linearly tuned between the enhancement and depletion modes. Finally, the first ever example of transparent flexible thin film metal oxide transistor on a polyamide substrate created using this simple technique is demonstrated. Finally, this study demonstrates the potential of field-induced activation as a promising alternative to traditional postdeposition thermal annealing which opens the door to wide scale implementation into flexible electronic applications.

  11. Cylindrical matrix device with a circular release area with inhomogeneous diffusivity

    NASA Astrophysics Data System (ADS)

    Cuartas Velez, Carlos Alfredo

    2013-05-01

    A cylindrical matrix device with a circular release area with inhomogeneous diffusivity was analyzed using a Laplace transform-based method, using Bromwich integral and residue theorem. The two-dimensional model represented a pharmaceutical agent uniformly distributed in a polymeric matrix with a diffusivity spatially modulated, surrounded by an impermeable layer. The pharmaceutical agent could be transferred only through a small hole centered at the top surface of the cylinder. A closed-form solution was obtained in terms of Bessel functions with the aim to help study the effects of design parameters and geometries on the cumulative amount of pharmaceutical agent released. The cumulative flux of pharmaceutical agent increased with the mass transfer and diffusion coefficients and decreased with any increment in the device's length and variations of the diffusivity coefficients. The delivery rate was described by an effective time constant calculated from Laplace transforms and using Bessel functions and their zeros. Reducing the orifice diameter or fabricating a longer system would delay transport of the medication. Simplified expressions for the release profile and the time constant were derived for special design cases.

  12. Nanoporous noninvasive cellular electrical activity-based analysis devices.

    PubMed

    Prasad, Shalini; Quijano, Jorge

    2007-03-01

    In recent years, rapid advancements have been made in the biomedical applications of microtechnology and nanotechnology. While the focus of such technologies have been primarily on in vitro analytical and diagnostic tools, more recently in vivo therapeutic and sensing applications have gained attention. The long-term integration of cells with inorganic materials provides the basis for novel sensing platforms. The work presented here focuses on the ability to maintain cells long-term in nanoporous silicon-based microenvironments. This article describes the creation of nanoporous, biocompatible, alumina membranes as a platform for incorporation into a cell-based device targeted for in situ recording of cellular electrical activity variations due to the changes associated with the surrounding microenvironments. Studies described herein focus on the interaction of nanoporous alumina substrates embedded in silicon patterned with cells of interest. The fidelity of such a system is demonstrated in terms of viability, proliferation, and functionality. The capability of such microfabricated nanoporous membranes, as in vitro for cell-based assays for sensing and drug delivery applications, is also demonstrated. It has potential in vivo application for therapeutic immunoisolation.

  13. SHADE: A Shape-Memory-Activated Device Promoting Ankle Dorsiflexion

    NASA Astrophysics Data System (ADS)

    Pittaccio, S.; Viscuso, S.; Rossini, M.; Magoni, L.; Pirovano, S.; Villa, E.; Besseghini, S.; Molteni, F.

    2009-08-01

    Acute post-stroke rehabilitation protocols include passive mobilization as a means to prevent contractures. A device (SHADE) that provides repetitive passive motion to a flaccid ankle by using shape memory alloy actuators could be of great help in providing this treatment. A suitable actuator was designed as a cartridge of approximately 150 × 20 × 15 mm, containing 2.5 m of 0.25 mm diameter NiTi wire. This actuator was activated by Joule’s effect employing a 7 s current input at 0.7 A, which provided 10 N through 76 mm displacement. Cooling and reset by natural convection took 30 s. A prototype of SHADE was assembled with two thermoplastic shells hinged together at the ankle and strapped on the shin and foot. Two actuators were fixed on the upper shell while an inextensible thread connected each NiTi wire to the foot shell. The passive ankle motion (passive range of motion, PROM) generated by SHADE was evaluated optoelectronically on three flaccid patients (58 ± 5 years old); acceptability was assessed by a questionnaire presented to further three flaccid patients (44 ± 11.5 years old) who used SHADE for 5 days, 30 min a day. SHADE was well accepted by all patients, produced good PROM, and caused no pain. The results prove that suitable limb mobilization can be produced by SMA actuators.

  14. Active pixel as dosimetric device for interventional radiology

    NASA Astrophysics Data System (ADS)

    Servoli, L.; Baldaccini, F.; Biasini, M.; Checcucci, B.; Chiocchini, S.; Cicioni, R.; Conti, E.; Di Lorenzo, R.; Dipilato, A. C.; Esposito, A.; Fanó, L.; Paolucci, M.; Passeri, D.; Pentiricci, A.; Placidi, P.

    2013-08-01

    Interventional Radiology (IR) is a subspecialty of radiology comprehensive of all minimally invasive diagnostic and therapeutic procedures performed using radiological devices to obtain image guidance. The interventional procedures are potentially harmful for interventional radiologists and medical staff due to the X-ray diffusion by the patient's body. The characteristic energy range of the diffused photons spans few tens of keV. In this work we will present a proposal for a new X-ray sensing element in the energy range of interest for IR procedures. The sensing element will then be assembled in a dosimeter prototype, capable of real-time measurement, packaged in a small form-factor, with wireless communication and no external power supply to be used for individual operators dosimetry for IR procedures. For the sensor, which is the heart of the system, we considered three different Active Pixel Sensors (APS). They have shown a good capability as single X-ray photon detectors, up to several tens keV photon energy. Two dosimetric quantities have been considered, the number of detected photons and the measured energy deposition. Both observables have a linear dependence with the dose, as measured by commercial dosimeters. The uncertainties in the measurement are dominated by statistic and can be pushed at ˜5% for all the sensors under test.

  15. Method and device for remotely monitoring an area using a low peak power optical pump

    DOEpatents

    Woodruff, Steven D.; Mcintyre, Dustin L.; Jain, Jinesh C.

    2014-07-22

    A method and device for remotely monitoring an area using a low peak power optical pump comprising one or more pumping sources, one or more lasers; and an optical response analyzer. Each pumping source creates a pumping energy. The lasers each comprise a high reflectivity mirror, a laser media, an output coupler, and an output lens. Each laser media is made of a material that emits a lasing power when exposed to pumping energy. Each laser media is optically connected to and positioned between a corresponding high reflectivity mirror and output coupler along a pumping axis. Each output coupler is optically connected to a corresponding output lens along the pumping axis. The high reflectivity mirror of each laser is optically connected to an optical pumping source from the one or more optical pumping sources via an optical connection comprising one or more first optical fibers.

  16. Development of a laboratory demonstration model active cleaning device

    NASA Technical Reports Server (NTRS)

    Shannon, R. L.; Gillette, R. B.

    1975-01-01

    A laboratory demonstration model of a device for removing contaminant films from optical surfaces in space was developed. The development of a plasma tube, which would produce the desired cleaning effects under high vacuum conditions, represented the major problem in the program. This plasma tube development is discussed, and the resulting laboratory demonstration-model device is described.

  17. Diagnostic for two-mode variable valve activation device

    SciTech Connect

    Fedewa, Andrew M

    2014-01-07

    A method is provided for diagnosing a multi-mode valve train device which selectively provides high lift and low lift to a combustion valve of an internal combustion engine having a camshaft phaser actuated by an electric motor. The method includes applying a variable electric current to the electric motor to achieve a desired camshaft phaser operational mode and commanding the multi-mode valve train device to a desired valve train device operational mode selected from a high lift mode and a low lift mode. The method also includes monitoring the variable electric current and calculating a first characteristic of the parameter. The method also includes comparing the calculated first characteristic against a predetermined value of the first characteristic measured when the multi-mode valve train device is known to be in the desired valve train device operational mode.

  18. Remedial activities effectiveness verification in tailing areas.

    PubMed

    Kluson, J; Thinova, L; Neznal, M; Svoboda, T

    2015-06-01

    The complex radiological study of the basin of sludge from the uranium ore mining and preprocessing was done. Air kerma rates (including its spectral analysis) at the reference height of 1 m above ground over the whole area were measured and radiation fields mapped during two measuring campaigns (years 2009 and 2014). K, U and Th concentrations in sludge and concentrations in depth profiles (including radon concentration and radon exhalation rates) in selected points were determined using gamma spectrometry for in situ as well as laboratory samples measurement. Results were used for the analysis, design evaluation and verification of the efficiency of the remediation measures. Efficiency of the sludge basin covering by the inert material was modelled using MicroShield code.

  19. Effects of a wireless local area network (LAN) system, a telemetry system, and electrosurgical devices on medical devices in a hospital environment.

    PubMed

    Tan, K S; Hinberg, I

    2000-01-01

    Concerns have been raised about interference of wireless local area network (LAN) systems and telemetry systems with medical devices in hospitals. The authors have investigated the susceptibility of 65 electromedical devices to a wireless LAN system and a telemetry system in preselected areas of a hospital. Testing was based on the American National Standards Institute Standard C63.18. The wireless LAN system operated at 2.42 GHz with an output power of 100 mW. The telemetry system operated at 466 MHz with an output power of 4 mW. Of the 65 devices tested, only two hand-held Doppler units, a Mini Doppler Model D900 (Huntleigh Healthcare Ltd) and a Ultrasonic Doppler Model 811 (Parks Medical Electronics, Inc.), were affected by the LAN system. Placed within 10 cm of the LAN system in standby mode, both units emitted periodic high-pitched beating sounds, which could be misinterpreted as normal beating sounds from the patient. These changed to random static noise during data transmission by the LAN. Under normal conditions of use, a LAN system would never be placed this close to a medical device. The quality of data transmission from the LAN system changed from "good" to "acceptable" in the colonoscopy room. This deterioration in transmission quality could have been caused by the lead shielding in the room. Electrosurgical devices operating at 0.5 to 1 MHz did not affect the LAN system at distances up to 3 m. None of the devices was affected by the telemetry system. These findings suggest that wireless LAN systems and telemetry systems can be acceptable for use in hospitals. Nevertheless, other systems should be tested on potentially susceptible devices by the hospital before use.

  20. Compilation of historical information of 300 Area facilities and activities

    SciTech Connect

    Gerber, M.S.

    1992-12-01

    This document is a compilation of historical information of the 300 Area activities and facilities since the beginning. The 300 Area is shown as it looked in 1945, and also a more recent (1985) look at the 300 Area is provided.

  1. Fiber bragg grating sensor based device for simultaneous measurement of respiratory and cardiac activities.

    PubMed

    Chethana, K; Guru Prasad, A S; Omkar, S N; Asokan, S

    2017-02-01

    This paper reports a novel optical ballistocardiography technique, which is non-invasive, for the simultaneous measurement of cardiac and respiratory activities using a Fiber Bragg Grating Heart Beat Device (FBGHBD). The unique design of FBGHBD offers additional capabilities such as monitoring nascent morphology of cardiac and breathing activity, heart rate variability, heart beat rhythm, etc., which can assist in early clinical diagnosis of many conditions associated with heart and lung malfunctioning. The results obtained from the FBGHBD positioned around the pulmonic area on the chest have been evaluated against an electronic stethoscope which detects and records sound pulses originated from the cardiac activity. In order to evaluate the performance of the FBGHBD, quantitative and qualitative studies have been carried out and the results are found to be reliable and accurate, validating its potential as a standalone medical diagnostic device. The developed FBGHBD is simple in design, robust, portable, EMI proof, shock proof and non-electric in its operation which are desired features for any clinical diagnostic tool used in hospital environment.

  2. Noiseless Non-Reciprocity in a Parametric Active Device

    DTIC Science & Technology

    2011-04-01

    and isolators belong to an important class of microwave components employed in applications including the measurement of mesoscopic circuits at...devices such as circulators and isolators belong to an important class of microwave components employed in applications including the measurement of...class of microwave components employed in applications including the measurement of mesoscopic circuits at cryogenic temperatures. The measurement

  3. Symmetric miniaturized heating system for active microelectronic devices

    NASA Astrophysics Data System (ADS)

    McCracken, Michael; Mayer, Michael; Jourard, Isaac; Moon, Jeong-Tak; Persic, John

    2010-07-01

    To qualify interconnect technologies such as microelectronic fine wire bonds for mass production of integrated circuit (IC) packages, it is necessary to perform accelerated aging tests, e.g., to age a device at an elevated temperature or to subject the device to thermal cycling and measure the decrease of interconnect quality. There are downsides to using conventional ovens for this as they are relatively large and have relatively slow temperature change rates, and if electrical connections are required between monitoring equipment and the device being heated, they must be located inside the oven and may be aged by the high temperatures. Addressing these downsides, a miniaturized heating system (minioven) is presented, which can heat individual IC packages containing the interconnects to be tested. The core of this system is a piece of copper cut from a square shaped tube with high resistance heating wire looped around it. Ceramic dual in-line packages are clamped against either open end of the core. One package contains a Pt100 temperature sensor and the other package contains the device to be aged placed in symmetry to the temperature sensor. According to the temperature detected by the Pt100, a proportional-integral-derivative controller adjusts the power supplied to the heating wire. The system maintains a dynamic temperature balance with the core hot and the two symmetric sides with electrical connections to the device under test at a cooler temperature. Only the face of the package containing the device is heated, while the socket holding it remains below 75 °C when the oven operates at 200 °C. The minioven can heat packages from room temperature up to 200 °C in less than 5 min and maintain this temperature at 28 W power. During long term aging, a temperature of 200 °C was maintained for 1120 h with negligible resistance change of the heating wires after 900 h (heating wire resistance increased 0.2% over the final 220 h). The device is also subjected to

  4. Symmetric miniaturized heating system for active microelectronic devices.

    PubMed

    McCracken, Michael; Mayer, Michael; Jourard, Isaac; Moon, Jeong-Tak; Persic, John

    2010-07-01

    To qualify interconnect technologies such as microelectronic fine wire bonds for mass production of integrated circuit (IC) packages, it is necessary to perform accelerated aging tests, e.g., to age a device at an elevated temperature or to subject the device to thermal cycling and measure the decrease of interconnect quality. There are downsides to using conventional ovens for this as they are relatively large and have relatively slow temperature change rates, and if electrical connections are required between monitoring equipment and the device being heated, they must be located inside the oven and may be aged by the high temperatures. Addressing these downsides, a miniaturized heating system (minioven) is presented, which can heat individual IC packages containing the interconnects to be tested. The core of this system is a piece of copper cut from a square shaped tube with high resistance heating wire looped around it. Ceramic dual in-line packages are clamped against either open end of the core. One package contains a Pt100 temperature sensor and the other package contains the device to be aged placed in symmetry to the temperature sensor. According to the temperature detected by the Pt100, a proportional-integral-derivative controller adjusts the power supplied to the heating wire. The system maintains a dynamic temperature balance with the core hot and the two symmetric sides with electrical connections to the device under test at a cooler temperature. Only the face of the package containing the device is heated, while the socket holding it remains below 75 degrees C when the oven operates at 200 degrees C. The minioven can heat packages from room temperature up to 200 degrees C in less than 5 min and maintain this temperature at 28 W power. During long term aging, a temperature of 200 degrees C was maintained for 1120 h with negligible resistance change of the heating wires after 900 h (heating wire resistance increased 0.2% over the final 220 h). The

  5. Evaluating the Safety Profile of Non-Active Implantable Medical Devices Compared with Medicines.

    PubMed

    Pane, Josep; Coloma, Preciosa M; Verhamme, Katia M C; Sturkenboom, Miriam C J M; Rebollo, Irene

    2017-01-01

    Recent safety issues involving non-active implantable medical devices (NAIMDs) have highlighted the need for better pre-market and post-market evaluation. Some stakeholders have argued that certain features of medicine safety evaluation should also be applied to medical devices. Our objectives were to compare the current processes and methodologies for the assessment of NAIMD safety profiles with those for medicines, identify potential gaps, and make recommendations for the adoption of new methodologies for the ongoing benefit-risk monitoring of these devices throughout their entire life cycle. A literature review served to examine the current tools for the safety evaluation of NAIMDs and those for medicines. We searched MEDLINE using these two categories. We supplemented this search with Google searches using the same key terms used in the MEDLINE search. Using a comparative approach, we summarized the new product design, development cycle (preclinical and clinical phases), and post-market phases for NAIMDs and drugs. We also evaluated and compared the respective processes to integrate and assess safety data during the life cycle of the products, including signal detection, signal management, and subsequent potential regulatory actions. The search identified a gap in NAIMD safety signal generation: no global program exists that collects and analyzes adverse events and product quality issues. Data sources in real-world settings, such as electronic health records, need to be effectively identified and explored as additional sources of safety information, particularly in some areas such as the EU and USA where there are plans to implement the unique device identifier (UDI). The UDI and other initiatives will enable more robust follow-up and assessment of long-term patient outcomes. The safety evaluation system for NAIMDs differs in many ways from those for drugs, but both systems face analogous challenges with respect to monitoring real-world usage. Certain features

  6. Lithographically patterned thin activated carbon films as a new technology platform for on-chip devices.

    PubMed

    Wei, Lu; Nitta, Naoki; Yushin, Gleb

    2013-08-27

    Continuous, smooth, visibly defect-free, lithographically patterned activated carbon films (ACFs) are prepared on the surface of silicon wafers. Depending on the synthesis conditions, porous ACFs can either remain attached to the initial substrate or be separated and transferred to another dense or porous substrate of interest. Tuning the activation conditions allows one to change the surface area and porosity of the produced carbon films. Here we utilize the developed thin ACF technology to produce prototypes of functional electrical double-layer capacitor devices. The synthesized thin carbon film electrodes demonstrated very high capacitance in excess of 510 F g(-1) (>390 F cm(-3)) at a slow cyclic voltammetry scan rate of 1 mV s(-1) and in excess of 325 F g(-1) (>250 F cm(-3)) in charge-discharge tests at an ultrahigh current density of 45,000 mA g(-1). Good stability was demonstrated after 10,000 galvanostatic charge-discharge cycles. The high values of the specific and volumetric capacitances of the selected ACF electrodes as well as the capacity retention at high current densities demonstrated great potential of the proposed technology for the fabrication of various on-chip devices, such as micro-electrochemical capacitors.

  7. Integrated Electromechanical Devices for Active Control of Vibration and Sound

    DTIC Science & Technology

    1997-11-01

    of peak power • Minimize ambient noise generation broadband and narrowband • Standard temperature (-25C--55C) with possible extended operation • Must...operate in a vacuum and in non-volatile fluids • Minimize heat generation , EMI, and outgassing • Baseline for application to flat surfaces but allow... generation . An actuator integrated in an electromechanical device could generate sufficient internal heat to affect other components, or alter its

  8. Microelectromechanical System (MEMS) Device Being Developed for Active Cooling and Temperature Control

    NASA Technical Reports Server (NTRS)

    Beach, Duane E.

    2003-01-01

    High-capacity cooling options remain limited for many small-scale applications such as microelectronic components, miniature sensors, and microsystems. A microelectromechanical system (MEMS) using a Stirling thermodynamic cycle to provide cooling or heating directly to a thermally loaded surface is being developed at the NASA Glenn Research Center to meet this need. The device can be used strictly in the cooling mode or can be switched between cooling and heating modes in milliseconds for precise temperature control. Fabrication and assembly employ techniques routinely used in the semiconductor processing industry. Benefits of the MEMS cooler include scalability to fractions of a millimeter, modularity for increased capacity and staging to low temperatures, simple interfaces, limited failure modes, and minimal induced vibration. The MEMS cooler has potential applications across a broad range of industries such as the biomedical, computer, automotive, and aerospace industries. The basic capabilities it provides can be categorized into four key areas: 1) Extended environmental temperature range in harsh environments; 2) Lower operating temperatures for electronics and other components; 3) Precision spatial and temporal thermal control for temperature-sensitive devices; and 4) The enabling of microsystem devices that require active cooling and/or temperature control. The rapidly expanding capabilities of semiconductor processing in general, and microsystems packaging in particular, present a new opportunity to extend Stirling-cycle cooling to the MEMS domain. The comparatively high capacity and efficiency possible with a MEMS Stirling cooler provides a level of active cooling that is impossible at the microscale with current state-of-the-art techniques. The MEMS cooler technology builds on decades of research at Glenn on Stirling-cycle machines, and capitalizes on Glenn s emerging microsystems capabilities.

  9. Impact of optical antennas on active optoelectronic devices.

    PubMed

    Bonakdar, Alireza; Mohseni, Hooman

    2014-10-07

    Remarkable progress has been made in the fabrication and characterization of optical antennas that are integrated with optoelectronic devices. Herein, we describe the fundamental reasons for and experimental evidence of the dramatic improvements that can be achieved by enhancing the light-matter interaction via an optical antenna in both photon-emitting and -detecting devices. In addition, integration of optical antennas with optoelectronic devices can lead to the realization of highly compact multifunctional platforms for future integrated photonics, such as low-cost lab-on-chip systems. In this review paper, we further focus on the effect of optical antennas on the detectivity of infrared photodetectors. One particular finding is that the antenna can have a dual effect on the specific detectivity, while it can elevate light absorption efficiency of sub-wavelength detectors, it can potentially increase the noise of the detectors due to the enhanced spontaneous emission rate. In particular, we predict that the detectivity of interband photon detectors can be negatively affected by the presence of optical antennas across a wide wavelength region covering visible to long wavelength infrared bands. In contrast, the detectivity of intersubband detectors could be generally improved with a properly designed optical antenna.

  10. Device and method for enhanced collection and assay of chemicals with high surface area ceramic

    DOEpatents

    Addleman, Raymond S.; Li, Xiaohong Shari; Chouyyok, Wilaiwan; Cinson, Anthony D.; Bays, John T.; Wallace, Krys

    2016-02-16

    A method and device for enhanced capture of target analytes is disclosed. This invention relates to collection of chemicals for separations and analysis. More specifically, this invention relates to a solid phase microextraction (SPME) device having better capability for chemical collection and analysis. This includes better physical stability, capacity for chemical collection, flexible surface chemistry and high affinity for target analyte.

  11. Measuring steps with the Fitbit activity tracker: an inter-device reliability study.

    PubMed

    Dontje, Manon L; de Groot, Martijn; Lengton, Remko R; van der Schans, Cees P; Krijnen, Wim P

    2015-01-01

    Activity trackers like Fitbit are used for self-tracking of physical activity by an increasing number of individuals. Comparing physical activity scores with peers can contribute to the desired behavioural change. However, for meaningful social comparison a high inter-device reliability is paramount. This study aimed to determine the inter-device reliability of Fitbit activity trackers in measuring steps. Ten activity trackers (Fitbit Ultra) were worn by a single person (male, 46 years) during eight consecutive days. Inter-device reliability was assessed on three different levels of aggregation (minutes, hours, days) with various methods, including intra-class correlation coefficient (ICC), Bland-Altman plots, limits of agreement (LOA) and Mixed Model Analysis. Results showed that the inter-device reliability of the Fitbit in measuring steps is good at all levels of aggregation (minutes, hours, days), but especially when steps were measured per day. This implies that individuals can reliably compare their daily physical activity scores with peers.

  12. rf-activated emergency locating and illuminating devices

    NASA Astrophysics Data System (ADS)

    Strong, Maurice L., III

    1995-05-01

    Law enforcement officials and medical personnel are, with increasing regularity, becoming involved in accident or hostage situations requiring transport of individuals by air. At the present time there are few acceptable or portable means for identification and demarcation of appropriate landing areas for inbound emergency aircraft in unprepared areas. The following paper describes a low cost, portable, and light weight solution to the problem of how to effectively demarcate a temporary landing zone as well as any hazards for use to assist pilots landing in unprepared areas.

  13. Emerging Vocabulary Learning: From a Perspective of Activities Facilitated by Mobile Devices

    ERIC Educational Resources Information Center

    Hu, Zengning

    2013-01-01

    This paper examines the current mobile vocabulary learning practice to discover how far mobile devices are being used to support vocabulary learning. An activity-centered perspective is undertaken, with the consideration of new practice against existing theories of learning activities including behaviorist activities, constructivist activities,…

  14. Feasibility of using a compact elliptical device to increase energy expenditure during sedentary activities

    PubMed Central

    Rovniak, Liza S.; Denlinger, LeAnn; Duveneck, Ellen; Sciamanna, Christopher N.; Kong, Lan; Freivalds, Andris; Ray, Chester A.

    2013-01-01

    Objectives This study aimed to evaluate the feasibility of using a compact elliptical device to increase energy expenditure during sedentary activities. A secondary aim was to evaluate if two accelerometers attached to the elliptical device could provide reliable and valid assessments of participants’ frequency and duration of elliptical device use. Design Physically inactive adults (n = 32, age range = 25–65) were recruited through local advertisements and selected using stratified random sampling based on sex, body mass index (BMI), and age. Methods Indirect calorimetry was used to assess participants’ energy expenditure while seated and while using the elliptical device at a self-selected intensity level. Participants also self-reported their interest in using the elliptical device during sedentary activities. Two Actigraph GT3X accelerometers were attached to the elliptical device to record time-use patterns. Results Participants expended a median of 179.1 kilocalories per hour while using the elliptical device (range = 108.2–269.0), or a median of 87.9 more kilocalories (range = 19.7–178.6) than they would expend per hour of sedentary sitting. Participants reported high interest in using the elliptical device during TV watching and computer work, but relatively low interest in using the device during office meetings. Women reported greater interest in using the elliptical device than men. The two accelerometers recorded identical time-use patterns on the elliptical device and demonstrated concurrent validity with time-stamped computer records. Conclusions Compact elliptical devices could increase energy expenditure during sedentary activities, and may provide proximal environmental cues for increasing energy expenditure across multiple life domains. PMID:24035273

  15. Effect of copper and plastic intra-uterine devices on the fibrinolytic activity of the endometrium in the rat.

    PubMed

    Larsson, B; Liedholm, P; Astedt, B

    1975-01-01

    The effect of copper and plastic intrauterine devices (IUD) on the fibrinolytic activity of the endometrium was studied in the rat. A copper or a plastic device was placed in one of the uterine horns, while the other horn served as a control. Biopsy specimens were obtained from both horns and examined histochemically. The copper concentration was determined by atomic absorption spectroscopy. The fibrinolytic activity of the control horn was found to be localized to small vessels in the outer layer of the uterine wall, while that of the endometrium was low. Plastic as well as copper IUDs increased the fibrinolytic activity which, in contrast with what was seen in the controls, was localized to the endometrium. Compared with the effect of the plastic device, the increase in the fibrinolytic activity induced by the copper device was more widespread in the endometrial area and was accompanied by an increase in the concentration of copper. These findings might help to explain why the contraceptive effect of IUDs is more reliable when they are partly coated with copper.

  16. A portable inhalational induction device provides co-operative induction of anaesthesia in preanaesthetic area for children

    PubMed Central

    Yun, Mi-Ja; Na, Hyo-Seok; Shin, Young Duck; Han, Jun-Sung; Hwang, Jung-Won; Kim, Chong Soo

    2010-01-01

    Background We introduce a new, simple portable inhalational induction device (PD) that provides co-operative inhalational induction of anaesthesia using N2O and subsequent sevoflurane in the preanaesthetic induction area in children. Methods Forty-five children (30 to 94 months old age, <35 kg) who were scheduled to undergo simple operations were assigned randomly to one of three regimens. Patients were encouraged by their parents to inhale N2O followed by sevoflurane (PD N2O-sevo group) or sevoflurane (PD sevo group) using a portable inhalational induction device in the preanaesthetic induction area until they were unable to respond to their names. They were then transferred to the operating room while maintaining inhalation of sevoflurane via the device. The control group underwent conventional inhalational induction in the operating room with the parents in attendance. Results Patients in the PD N2O-sevo group had a higher co-operative inhalation frequency than the patients in the PD sevo or the control group. Anaesthesia induction in the PD N2O-sevo and the PD sevo groups were faster than in the control group. Parent satisfaction score (0-100) was higher for the PD N2O-sevo group than for the control group. Conclusions A new portable inhalational induction device allows faster induction in co-operation with parents present in the preanaesthetic induction area compared to conventional inhalational induction in the unfamiliar operating room with the parents in attendance. PMID:20589175

  17. Haptic device development based on electro static force of cellulose electro active paper

    NASA Astrophysics Data System (ADS)

    Yun, Gyu-young; Kim, Sang-Youn; Jang, Sang-Dong; Kim, Dong-Gu; Kim, Jaehwan

    2011-04-01

    Haptic is one of well-considered device which is suitable for demanding virtual reality applications such as medical equipment, mobile devices, the online marketing and so on. Nowadays, many of concepts for haptic devices have been suggested to meet the demand of industries. Cellulose has received much attention as an emerging smart material, named as electro-active paper (EAPap). The EAPap is attractive for mobile haptic devices due to its unique characteristics in terms of low actuation power, suitability for thin devices and transparency. In this paper, we suggest a new concept of haptic actuator with the use of cellulose EAPap. Its performance is evaluated depending on various actuation conditions. As a result, cellulose electrostatic force actuator shows a large output displacement and fast response, which is suitable for mobile haptic devices.

  18. MEMS Device Being Developed for Active Cooling and Temperature Control

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.

    2001-01-01

    High-capacity cooling options remain limited for many small-scale applications such as microelectronic components, miniature sensors, and microsystems. A microelectromechanical system (MEMS) is currently under development at the NASA Glenn Research Center to meet this need. It uses a thermodynamic cycle to provide cooling or heating directly to a thermally loaded surface. The device can be used strictly in the cooling mode, or it can be switched between cooling and heating modes in milliseconds for precise temperature control. Fabrication and assembly are accomplished by wet etching and wafer bonding techniques routinely used in the semiconductor processing industry. Benefits of the MEMS cooler include scalability to fractions of a millimeter, modularity for increased capacity and staging to low temperatures, simple interfaces and limited failure modes, and minimal induced vibration.

  19. 78 FR 41065 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ... HUMAN SERVICES Food and Drug Administration Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices; Third-Party Review Under the Food and Drug Administration Modernization Act AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and...

  20. Water Pollution Scrubber Activity Simulates Pollution Control Devices.

    ERIC Educational Resources Information Center

    Kennedy, Edward C., III; Waggoner, Todd C.

    2003-01-01

    A laboratory activity caused students to think actively about water pollution. The students realized that it would be easier to keep water clean than to remove pollutants. They created a water scrubbing system allowing them to pour water in one end and have it emerge clean at the other end. (JOW)

  1. Fabric-based integrated energy devices for wearable activity monitors.

    PubMed

    Jung, Sungmook; Lee, Jongsu; Hyeon, Taeghwan; Lee, Minbaek; Kim, Dae-Hyeong

    2014-09-01

    A wearable fabric-based integrated power-supply system that generates energy triboelectrically using human activity and stores the generated energy in an integrated supercapacitor is developed. This system can be utilized as either a self-powered activity monitor or as a power supply for external wearable sensors. These demonstrations give new insights for the research of wearable electronics.

  2. Comparing wearable devices with wet and textile electrodes for activity recognition.

    PubMed

    Lokare, Namita; Gonzalez, Laura; Lobaton, Edgar

    2016-08-01

    This paper explores the idea of identifying activities from muscle activation which is captured by wearable ECG recording devices that use wet and textile electrodes. Most of the devices available today filter out the high frequency components to retain only the signal related to an ECG. We explain how the high frequency components that correspond to muscle activation can be extracted from the recorded signal and can be used to identify activities. We notice that is possible to obtain good performance for both the wet and dry electrodes. However, we observed that signals from the dry textile electrodes introduce less artifacts associated with muscle activation.

  3. Semantic Wavelet-Induced Frequency-Tagging (SWIFT) Periodically Activates Category Selective Areas While Steadily Activating Early Visual Areas

    PubMed Central

    Koenig-Robert, Roger; VanRullen, Rufin; Tsuchiya, Naotsugu

    2015-01-01

    Primate visual systems process natural images in a hierarchical manner: at the early stage, neurons are tuned to local image features, while neurons in high-level areas are tuned to abstract object categories. Standard models of visual processing assume that the transition of tuning from image features to object categories emerges gradually along the visual hierarchy. Direct tests of such models remain difficult due to confounding alteration in low-level image properties when contrasting distinct object categories. When such contrast is performed in a classic functional localizer method, the desired activation in high-level visual areas is typically accompanied with activation in early visual areas. Here we used a novel image-modulation method called SWIFT (semantic wavelet-induced frequency-tagging), a variant of frequency-tagging techniques. Natural images modulated by SWIFT reveal object semantics periodically while keeping low-level properties constant. Using functional magnetic resonance imaging (fMRI), we indeed found that faces and scenes modulated with SWIFT periodically activated the prototypical category-selective areas while they elicited sustained and constant responses in early visual areas. SWIFT and the localizer were selective and specific to a similar extent in activating category-selective areas. Only SWIFT progressively activated the visual pathway from low- to high-level areas, consistent with predictions from standard hierarchical models. We confirmed these results with criterion-free methods, generalizing the validity of our approach and show that it is possible to dissociate neural activation in early and category-selective areas. Our results provide direct evidence for the hierarchical nature of the representation of visual objects along the visual stream and open up future applications of frequency-tagging methods in fMRI. PMID:26691722

  4. Semantic Wavelet-Induced Frequency-Tagging (SWIFT) Periodically Activates Category Selective Areas While Steadily Activating Early Visual Areas.

    PubMed

    Koenig-Robert, Roger; VanRullen, Rufin; Tsuchiya, Naotsugu

    2015-01-01

    Primate visual systems process natural images in a hierarchical manner: at the early stage, neurons are tuned to local image features, while neurons in high-level areas are tuned to abstract object categories. Standard models of visual processing assume that the transition of tuning from image features to object categories emerges gradually along the visual hierarchy. Direct tests of such models remain difficult due to confounding alteration in low-level image properties when contrasting distinct object categories. When such contrast is performed in a classic functional localizer method, the desired activation in high-level visual areas is typically accompanied with activation in early visual areas. Here we used a novel image-modulation method called SWIFT (semantic wavelet-induced frequency-tagging), a variant of frequency-tagging techniques. Natural images modulated by SWIFT reveal object semantics periodically while keeping low-level properties constant. Using functional magnetic resonance imaging (fMRI), we indeed found that faces and scenes modulated with SWIFT periodically activated the prototypical category-selective areas while they elicited sustained and constant responses in early visual areas. SWIFT and the localizer were selective and specific to a similar extent in activating category-selective areas. Only SWIFT progressively activated the visual pathway from low- to high-level areas, consistent with predictions from standard hierarchical models. We confirmed these results with criterion-free methods, generalizing the validity of our approach and show that it is possible to dissociate neural activation in early and category-selective areas. Our results provide direct evidence for the hierarchical nature of the representation of visual objects along the visual stream and open up future applications of frequency-tagging methods in fMRI.

  5. Planar fuel cell utilizing nail current collectors for increased active surface area

    DOEpatents

    George, Thomas J.; Meacham, G. B. Kirby

    2002-03-26

    A plurality of nail current collector members are useful in the gas flow passages of an electrochemical device to optimize the active surfaces of the device and to provide structural support. In addition, the thicknesses of cathode and anode layers within the electrochemical device are varied according to current flow through the device to reduce resistance and increase operating efficiency.

  6. Planar fuel cell utilizing nail current collectors for increased active surface area

    SciTech Connect

    George, Thomas J.; Meacham, G.B. Kirby

    1999-11-26

    A plurality of nail current collector members are useful in the gas flow passages of an electrochemical device to optimize the active surfaces of the device and to provide structural support. In addition, the thicknesses of cathode and anode layers within the electrochemical device are varied according to current flow through the device to reduce resistance and increase operating efficiency.

  7. Development of closed-fitting-type walking assistance device for legs and evaluation of muscle activity.

    PubMed

    Ikehara, Tadaaki; Nagamura, Kazuteru; Ushida, Takurou; Tanaka, Eiichirou; Saegusa, Shozo; Kojima, Sho; Yuge, Louis

    2011-01-01

    A walking assistance device using a flexible shaft was developed. The combination of a flexible shaft with a worm gear was successfully adopted on this device to simplify its appearance and reduce its size. A hybrid - control system on this device controls both torque and angle at the ankle and knee joints. In this system, the torsional spring constant of the flexible shaft is taken into account by the motor in controlling the power and angle of rotation of the motor. To expand the area in which a person may use the device, it is equipped with a self-contained system powered by a Lithium-ion battery and controlled by an SH-4 microcomputer and actuators, consisting of motors and gears, all of which are carried in a small backpack. Consequently, persons using the device may walk freely in both indoor and outdoor environments.

  8. Measurements of the PLT and PDX device activation

    SciTech Connect

    Stavely, J.; Barnes, C.W.; Chrien, R.E.; Strachan, J.D.

    1981-09-01

    Measurements of the activation levels around the PLT and PDX tokamaks have been made using a Ge(Li) gamma spectrometer and a Geiger counter. The activation results from radiation induced in the plasma by 14 MeV neutrons from the d(t,n)..cap alpha.. fusion reaction, 14.7 MeV protons from the d(/sup 3/He,p)..cap alpha.. fusion reaction, 10 ..-->.. 20 MeV hard x-rays from runaway electron induced bremmstrahlung, and 2.5 MeV neutrons from the d(d,n)/sup 3/He fusion reaction. The magnitude of the activation is compared to that predicted for PDX on the basis of one-dimensional activation codes.

  9. Active devices based on organic semiconductors for wearable applications.

    PubMed

    Barbaro, Massimo; Caboni, Alessandra; Cosseddu, Piero; Mattana, Giorgio; Bonfiglio, Annalisa

    2010-05-01

    Plastic electronics is an enabling technology for obtaining active (transistor based) electronic circuits on flexible and/or nonplanar surfaces. For these reasons, it appears as a perfect candidate to promote future developments of wearable electronics toward the concept of fabrics and garments made by functional (in this case, active electronic) yarns. In this paper, a panoramic view of recent achievements and future perspectives is given.

  10. An adaptive Hidden Markov Model for activity recognition based on a wearable multi-sensor device

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Human activity recognition is important in the study of personal health, wellness and lifestyle. In order to acquire human activity information from the personal space, many wearable multi-sensor devices have been developed. In this paper, a novel technique for automatic activity recognition based o...

  11. Devices with extended area structures for mass transfer processing of fluids

    DOEpatents

    TeGrotenhuis, Ward E.; Wegeng, Robert S.; Whyatt, Greg A.; King, David L.; Brooks, Kriston P.; Stenkamp, Victoria S.

    2009-04-21

    A microchannel device includes several mass transfer microchannels to receive a fluid media for processing at least one heat transfer microchannel in fluid communication with a heat transfer fluid defined by a thermally conductive wall, and at several thermally conductive fins each connected to the wall and extending therefrom to separate the mass transfer microchannels from one another. In one form, the device may optionally include another heat transfer microchannel and corresponding wall that is positioned opposite the first wall and has the fins and the mass transfer microchannels extending therebetween.

  12. Alternative Patterning Process for Realization of Large-Area, Full-Color, Active Quantum Dot Display.

    PubMed

    Park, Joon-Suh; Kyhm, Jihoon; Kim, Hong Hee; Jeong, Shinyoung; Kang, JoonHyun; Lee, Song-Ee; Lee, Kyu-Tae; Park, Kisun; Barange, Nilesh; Han, JiYeong; Song, Jin Dong; Choi, Won Kook; Han, Il Ki

    2016-11-09

    Although various colloidal quantum dot (QD) coating and patterning techniques have been developed to meet the demands in optoelectronic applications over the past years, each of the previously demonstrated methods has one or more limitations and trade-offs in forming multicolor, high-resolution, or large-area patterns of QDs. In this study, we present an alternative QD patterning technique using conventional photolithography combined with charge-assisted layer-by-layer (LbL) assembly to solve the trade-offs of the traditional patterning processes. From our demonstrations, we show repeatable QD patterning process that allows multicolor QD patterns in both large-area and microscale. Also, we show that the QD patterns are robust against additional photolithography processes and that the thickness of the QD patterns can be controlled at each position. To validate that this process can be applied to actual device applications as an active material, we have fabricated inverted, differently colored, active QD light-emitting device (QD-LED) on a pixelated substrate, which achieved maximum electroluminescence intensity of 23 770 cd/m(2), and discussed the results. From our findings, we believe that our process provides a solution to achieving both high-resolution and large-scale QD pattern applicable to not only display, but also to practical photonic device research and development.

  13. Defence force activities in marine protected areas: environmental management of Shoalwater Bay Training Area, Queensland, Australia

    NASA Astrophysics Data System (ADS)

    Wu, Wen; Wang, Xiaohua; Paull, David; Kesby, Julie

    2010-05-01

    Environmental management of military activities is of growing global concern by defence forces. As one of the largest landholders in Australia, the Australian Defence Force (ADF) is increasingly concerned with sustainable environmental management. This paper focuses on how the ADF is maintaining effective environmental management, especially in environmentally sensitive marine protected areas. It uses Shoalwater Bay Training Area (SWBTA) as a research example to examine environmental management strategies conducted by the ADF. SWBTA is one of the most significant Defence training areas in Australia, with a large number of single, joint and combined military exercises conducted in the area. With its maritime component contained in the Great Barrier Reef Marine Park (GBRMP), the Great Barrier Reef World Heritage Area (GBRWHA), and abutting Queensland’s State Marine Parks, it has high protection values. It is therefore vital for the ADF to adopt environmentally responsible management while they are conducting military activities. As to various tools employed to manage environmental performance, the ISO 14001 Environmental Management System (EMS) is widely used by the ADF. This paper examines military activities and marine environmental management within SWBTA, using the Talisman Saber (TS) exercise series as an example. These are extensive joint exercises conducted by the ADF and the United States defence forces. The paper outlines relevant legislative framework and environmental policies, analyses how the EMS operates in environmental management of military activities, and how military activities comply with these regulations. It discusses the implementation of the ADF EMS, including risk reduction measures, environmental awareness training, consultation and communication with stakeholders. A number of environmental management actions used in the TS exercises are presented to demonstrate the EMS application. Our investigations to this point indicate that the ADF is

  14. Re-active Passive (RAP) Devices for Control of Noise Transmission through a Panel

    NASA Technical Reports Server (NTRS)

    Carneal, James P.; Giovanardi, Marco; Fuller, Chris R.; Palumbo, Daniel L.

    2008-01-01

    Re-Active Passive (RAP) devices have been developed to control low frequency (<1000 Hz) noise transmission through a panel. These devices use a combination of active, re-active, and passive technologies packaged into a single unit to control a broad frequency range utilizing the strength of each technology over its best suited frequency range. The RAP device uses passive constrained layer damping to cover the relatively high frequency range (>200 Hz), reactive distributed vibration absorber) to cover the medium frequency range (75 to 250 Hz), and active control for controlling low frequencies (<200 Hz). The device was applied to control noise transmission through a panel mounted in a transmission loss test facility. Experimental results are presented for the bare panel, and combinations of passive treatment, reactive treatment, and active control. Results indicate that three RAP devices were able to increase the overall broadband (15-1000 Hz) transmission loss by 9.4 dB. These three devices added a total of 285 grams to the panel mass of 6.0 kg, or approximately 5%, not including control electronics.

  15. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: STORMWATER SOURCE AREA TREATMENT DEVICE: STORMWATER MANAGEMENT INC., STORMSCREEN� TREATMENT SYSTEM

    EPA Science Inventory

    Verification Testing of the Stormwater Management, Inc. StormScreen treatment technology was performed during a 12-month period starting in May, 2003. The system was previously installed in a city-owned right-of-way near downtown Griffin, GA., and is a device for removing trash,...

  16. Cognitive Neurostimulation: Learning to Volitionally Sustain Ventral Tegmental Area Activation.

    PubMed

    MacInnes, Jeff J; Dickerson, Kathryn C; Chen, Nan-kuei; Adcock, R Alison

    2016-03-16

    Activation of the ventral tegmental area (VTA) and mesolimbic networks is essential to motivation, performance, and learning. Humans routinely attempt to motivate themselves, with unclear efficacy or impact on VTA networks. Using fMRI, we found untrained participants' motivational strategies failed to consistently activate VTA. After real-time VTA neurofeedback training, however, participants volitionally induced VTA activation without external aids, relative to baseline, Pre-test, and control groups. VTA self-activation was accompanied by increased mesolimbic network connectivity. Among two comparison groups (no neurofeedback, false neurofeedback) and an alternate neurofeedback group (nucleus accumbens), none sustained activation in target regions of interest nor increased VTA functional connectivity. The results comprise two novel demonstrations: learning and generalization after VTA neurofeedback training and the ability to sustain VTA activation without external reward or reward cues. These findings suggest theoretical alignment of ideas about motivation and midbrain physiology and the potential for generalizable interventions to improve performance and learning.

  17. Radiofrequency identification and medical devices: the regulatory framework on electromagnetic compatibility. Part II: active implantable medical devices.

    PubMed

    Mattei, Eugenio; Censi, Federica; Triventi, Michele; Bartolini, Pietro; Calcagnini, Giovanni

    2012-05-01

    The number and the types of electromagnetic emitters to which patients with active implantable medical devices (AIMD) are exposed to in their daily activities have proliferated over the last decade. Radiofrequency identification (RFID) is an example of wireless technology applied in many fields. The interaction between RFID emitters and AIMD is an important issue for patients, industry and regulators, because of the risks associated with such interactions. The different AIMDs refer to different standards that address the electromagnetic immunity issue in different ways. Indeed, different test setups, immunity levels and rationales are used to guarantee that AIMDs are immune to electromagnetic nonionizing radiation. In this article, the regulatory framework concerning electromagnetic compatibility between RFID systems and AIMDs is analyzed to understand whether and how the application of the current AIMD standards allows for the effective control of the possible risks associated with RFID technology.

  18. Activation of Premotor Vocal Areas during Musical Discrimination

    ERIC Educational Resources Information Center

    Brown, Steven; Martinez, Michael J.

    2007-01-01

    Two same/different discrimination tasks were performed by amateur-musician subjects in this functional magnetic resonance imaging study: Melody Discrimination and Harmony Discrimination. Both tasks led to activations not only in classic working memory areas--such as the cingulate gyrus and dorsolateral prefrontal cortex--but in a series of…

  19. Activated carbon testing for the 200 area effluent treatment facility

    SciTech Connect

    Wagner, R.N.

    1997-01-17

    This report documents pilot and laboratory scale testing of activated carbon for use in the 200 Area Effluent Treatment Facility peroxide decomposer columns. Recommendations are made concerning column operating conditions and hardware design, the optimum type of carbon for use in the plant, and possible further studies.

  20. Spatial precision of population activity in primate area MT

    PubMed Central

    Morley, John W.; Solomon, Samuel G.

    2015-01-01

    The middle temporal (MT) area is a cortical area integral to the “where” pathway of primate visual processing, signaling the movement and position of objects in the visual world. The receptive field of a single MT neuron is sensitive to the direction of object motion but is too large to signal precise spatial position. Here, we asked if the activity of MT neurons could be combined to support the high spatial precision required in the where pathway. With the use of multielectrode arrays, we recorded simultaneously neural activity at 24–65 sites in area MT of anesthetized marmoset monkeys. We found that although individual receptive fields span more than 5° of the visual field, the combined population response can support fine spatial discriminations (<0.2°). This is because receptive fields at neighboring sites overlapped substantially, and changes in spatial position are therefore projected onto neural activity in a large ensemble of neurons. This fine spatial discrimination is supported primarily by neurons with receptive fields flanking the target locations. Population performance is degraded (by 13–22%) when correlations in neural activity are ignored, further reflecting the contribution of population neural interactions. Our results show that population signals can provide high spatial precision despite large receptive fields, allowing area MT to represent both the motion and the position of objects in the visual world. PMID:26041825

  1. SPECIAL MOTIVATIONAL ACTIVITIES FOR PROMOTING CERTAIN PROBLEM AREAS IN READING.

    ERIC Educational Resources Information Center

    DAWSON, MARVIN; SPENCER, GARY D.

    A CURRICULUM GUIDE PRODUCED AT AN INSERVICE TRAINING COURSE ON "PROBLEMS IN TEACHING READING" BY TEACHERS FROM CARROLL COUNTY SCHOOLS, GEORGIA, IN THE SPRING OF 1966 IS PRESENTED. IT OFFERS GENERAL MOTIVATIONAL READING ACTIVITIES WHICH PROMOTE GROWTH IN CERTAIN PROBLEM AREAS IN READING. RECOGNIZING THAT THERE CAN BE NO EFFECTIVE LEARNING…

  2. Prior probability modulates anticipatory activity in category-specific areas.

    PubMed

    Trapp, Sabrina; Lepsien, Jöran; Kotz, Sonja A; Bar, Moshe

    2016-02-01

    Bayesian models are currently a dominant framework for describing human information processing. However, it is not clear yet how major tenets of this framework can be translated to brain processes. In this study, we addressed the neural underpinning of prior probability and its effect on anticipatory activity in category-specific areas. Before fMRI scanning, participants were trained in two behavioral sessions to learn the prior probability and correct order of visual events within a sequence. The events of each sequence included two different presentations of a geometric shape and one picture of either a house or a face, which appeared with either a high or a low likelihood. Each sequence was preceded by a cue that gave participants probabilistic information about which items to expect next. This allowed examining cue-related anticipatory modulation of activity as a function of prior probability in category-specific areas (fusiform face area and parahippocampal place area). Our findings show that activity in the fusiform face area was higher when faces had a higher prior probability. The finding of a difference between levels of expectations is consistent with graded, probabilistically modulated activity, but the data do not rule out the alternative explanation of a categorical neural response. Importantly, these differences were only visible during anticipation, and vanished at the time of stimulus presentation, calling for a functional distinction when considering the effects of prior probability. Finally, there were no anticipatory effects for houses in the parahippocampal place area, suggesting sensitivity to stimulus material when looking at effects of prediction.

  3. Bio-nanotextured high aspect ratio micropillar arrays for high surface area energy storage devices

    NASA Astrophysics Data System (ADS)

    Chu, S.; Gerasopoulos, K.; Ghodssi, R.

    2015-12-01

    This paper presents fabrication and characterization of bio-nanotextured hierarchical nickel oxide (NiO) supercapacitor electrodes. The hierarchical electrode structure is created through self-assembly of Tobacco mosaic viruses (TMVs) on high aspect-ratio micropillar arrays. Enhanced assembly of the bio-nanoparticles was achieved by increasing TMV solution accessibility into the deep microcavities of the pillar arrays. Electrochemical characterization of the hierarchical NiO supercapacitor electrodes revealed a 25-fold increase in charge capacity compared to a planar NiO, and demonstrated excellent cycle stability over 1500 charge/discharge cycles at 2 mA/cm2. This study leverages the unique bio-nanoscaffolds for small scale energy storage devices through further optimization of the hierarchical structures and wetting techniques for significant improvements in micro/nano scale energy storage devices.

  4. On a portable memory device for physical activities and informations of maternal perception.

    PubMed

    Hasegawa, T; Horio, H; Makikawa, M; Bunki, H; Sasaki, K; Utsu, M; Sakakibara, S; Kanzaki, T; Kobayashi, H; Chiba, Y

    1988-01-01

    The condition of patients must be known to attending doctors for adequate management of a disease, particularly of high risk pregnancy. For this purpose, we have developed a portable computerized disease condition memory device to record the physical activities with maternal perception of fetal movement and uterine condition in daily life, both at home and during work. This device taken out by the patient is a small battery-driven CMOS 8 bit computer system (size: 107 x 80 x 30 mm, 240 g) and is equipped with push-botton switches on the upper side and a mercury switch inside it. The time of maternal perception of fetal movement and uterine contraction are recorded by the patient pressing the corresponding switch. Meanwhile the mercury switch serves as a acceleration sensor and the physical activities were measured by counting ON-OFF actions of the mercury switch caused by her movements. Consequently, the device has recorded physical activities automatically by wearing this unit all day long. The continuously recordable time is more than two weeks. The evaluation about the sensitivity of physical activity measurement has indicated that the mercury switch sensor was well related to the oxygen consumption rate in rest and mild exercise. Using this device to five pregnant women, the data showed the quantitative difference in physical activities between rest in bed and normal home life, and daily changes could be clearly observed. From these results, the physical activities and the condition of the patient in daily life can be followed by this device.

  5. Active Learning Approaches by Visualizing ICT Devices with Milliseconds Resolution for Deeper Understanding in Physics

    NASA Astrophysics Data System (ADS)

    Kobayashi, Akizo; Okiharu, Fumiko

    2010-07-01

    We are developing various modularized materials in physics education to overcome students' misconceptions by use of ICT, i.e. video analysis software and ultra-high-speed digital movies, motion detector, force sensors, current and voltage probes, temperature sensors etc. Furthermore, we also present some new modules of active learning approaches on electric circuit using high speed camera and voltage probes with milliseconds resolution. We are now especially trying to improve conceptual understanding by use of ICT devices with milliseconds resolution in various areas of physics education We give some modules of mass measurements by video analysis of collision phenomena by using high speed cameras—Casio EX-F1(1200 fps), EX-FH20(1000 fps) and EX-FC100/150(1000 fps). We present several new modules on collision phenomena to establish deeper understanding of conservation laws of momentum. We discuss some effective results of trial on a physics education training courses for science educators, and those for science teachers during the renewal years of teacher's license after every ten years in Japan. Finally, we discuss on some typical results of pre-test and post-test in our active learning approaches based on ICT, i.e. some evidence on improvements of physics education (increasing ratio of correct answer are 50%-level).

  6. Novel windows for "solar commodities": a device for CO2 reduction using plasmonic catalyst activation.

    PubMed

    Navarrete, Alexander; Muñoz, Sergio; Sanz-Moral, Luis M; Brandner, Juergen J; Pfeifer, Peter; Martín, Ángel; Dittmeyer, Roland; Cocero, María J

    2015-01-01

    A novel plasmonic reactor concept is proposed and tested to work as a visible energy harvesting device while allowing reactions to transform CO2 to be carried out. Particularly the reverse water gas shift (RWGS) reaction has been tested as a means to introduce renewable energy into the economy. The development of the new reactor concept involved the synthesis of a new composite capable of plasmonic activation with light, the development of an impregnation method to create a single catalyst reactor entity, and finally the assembly of a reaction system to test the reaction. The composite developed was based on a Cu/ZnO catalyst dispersed into transparent aerogels. This allows efficient light transmission and a high surface area for the catalyst. An effective yet simple impregnation method was developed that allowed introduction of the composites into glass microchannels. The activation of the reaction was made using LEDs that covered all the sides of the reactor allowing a high power delivery. The results of the reaction show a stable process capable of low temperature transformations.

  7. Design of a continuous passive and active motion device for hand rehabilitation.

    PubMed

    Birch, B; Haslam, E; Heerah, I; Dechev, N; Park, E J

    2008-01-01

    This paper presents the design of a novel, portable device for hand rehabilitation. The device provides for CPM (continuous passive motion) and CAM (continuous active motion) hand rehabilitation for patients recovering from damage such as flexor tendon repair and strokes. The device is capable of flexing/extending the MCP (metacarpophalangeal) and PIP (proximal interphalangeal) joints through a range of motion of 0 degrees to 90 degrees for both the joints independently. In this way, typical hand rehabilitation motions such as intrinsic plus, intrinsic minus, and a fist can be achieved without the need of any splints or attachments. The CPM mode is broken into two subgroups. The first mode is the use of preset waypoints for the device to cycle through. The second mode involves motion from a starting position to a final position, but senses the torque from the user during the cycle. Therefore the user can control the ROM by resisting when they are at the end of the desired motion. During the CPM modes the device utilizes a minimum jerk trajectory model under PD control, moving smoothly and accurately between preselected positions. CAM is the final mode where the device will actively resist the movement of the user. The user moves from a start to end position while the device produces a torque to resist the motion. This active resistance motion is a unique ability designed to mimic the benefits of a human therapist. Another unique feature of the device is its ability to independently act on both the MCP and PIP joints. The feedback sensing built into the device makes it capable of offering a wide and flexible range of rehabilitation programs for the hand.

  8. Monolithic microwave integrated circuit devices for active array antennas

    NASA Technical Reports Server (NTRS)

    Mittra, R.

    1984-01-01

    Two different aspects of active antenna array design were investigated. The transition between monolithic microwave integrated circuits and rectangular waveguides was studied along with crosstalk in multiconductor transmission lines. The boundary value problem associated with a discontinuity in a microstrip line is formulated. This entailed, as a first step, the derivation of the propagating as well as evanescent modes of a microstrip line. The solution is derived to a simple discontinuity problem: change in width of the center strip. As for the multiconductor transmission line problem. A computer algorithm was developed for computing the crosstalk noise from the signal to the sense lines. The computation is based on the assumption that these lines are terminated in passive loads.

  9. Effects of a Physical Education Supportive Curriculum and Technological Devices on Physical Activity

    ERIC Educational Resources Information Center

    Clapham, Emily Dean; Sullivan, Eileen C.; Ciccomascolo, Lori E.

    2015-01-01

    The purpose of this study was to examine the effects of a physical education supportive curriculum and technological devices, heart rate monitor (HRM) and pedometer (PED), on physical activity. A single-subject ABAB research design was used to examine amount and level of participation in physical activity among 106 suburban fourth and fifth…

  10. Activation of sensory-motor areas in sentence comprehension.

    PubMed

    Desai, Rutvik H; Binder, Jeffrey R; Conant, Lisa L; Seidenberg, Mark S

    2010-02-01

    The sensory-motor account of conceptual processing suggests that modality-specific attributes play a central role in the organization of object and action knowledge in the brain. An opposing view emphasizes the abstract, amodal, and symbolic character of concepts, which are thought to be represented outside the brain's sensory-motor systems. We conducted a functional magnetic resonance imaging study in which the participants listened to sentences describing hand/arm action events, visual events, or abstract behaviors. In comparison to visual and abstract sentences, areas associated with planning and control of hand movements, motion perception, and vision were activated when understanding sentences describing actions. Sensory-motor areas were activated to a greater extent also for sentences with actions that relied mostly on hands, as opposed to arms. Visual sentences activated a small area in the secondary visual cortex, whereas abstract sentences activated superior temporal and inferior frontal regions. The results support the view that linguistic understanding of actions partly involves imagery or simulation of actions, and relies on some of the same neural substrate used for planning, performing, and perceiving actions.

  11. Flexible, transparent and ultra-broadband photodetector based on large-area WSe2 film for wearable devices.

    PubMed

    Zheng, Zhaoqiang; Zhang, Tanmei; Yao, Jiandomg; Zhang, Yi; Xu, Jiarui; Yang, Guowei

    2016-06-03

    Although two-dimensional (2D) materials have attracted considerable research interest for use in the development of innovative wearable optoelectronic systems, the integrated optoelectronic performance of 2D materials photodetectors, including flexibility, transparency, broadband response and stability in air, remains quite low to date. Here, we demonstrate a flexible, transparent, high-stability and ultra-broadband photodetector made using large-area and highly-crystalline WSe2 films that were prepared by pulsed-laser deposition (PLD). Benefiting from the 2D physics of WSe2 films, this device exhibits excellent average transparency of 72% in the visible range and superior photoresponse characteristics, including an ultra-broadband detection spectral range from 370 to 1064 nm, reversible photoresponsivity approaching 0.92 A W(-1), external quantum efficiency of up to 180% and a relatively fast response time of 0.9 s. The fabricated photodetector also demonstrates outstanding mechanical flexibility and durability in air. Also, because of the wide compatibility of the PLD-grown WSe2 film, we can fabricate various photodetectors on multiple flexible or rigid substrates, and all these devices will exhibit distinctive switching behavior and superior responsivity. These indicate a possible new strategy for the design and integration of flexible, transparent and broadband photodetectors based on large-area WSe2 films, with great potential for practical applications in the wearable optoelectronic devices.

  12. In vitro release of cupric ion from intrauterine devices: influence of frame, shape, copper surface area and indomethacin.

    PubMed

    Zhang, Shuangshuang; Li, Ying; Yu, Panpan; Chen, Tong; Zhou, Weisai; Zhang, Wenli; Liu, Jianping

    2015-02-01

    The release of cupric ion from copper intrauterine device (Cu-IUD) in human uterus is essential for contraception. However, excessive cupric ion will cause cytotoxic effect. In this paper, we investigated the influence of device characteristics (frame, copper surface area, shape, copper type and indomethacin) on copper release for the efficacy and adverse effects vary with IUD types which may correlate to their different release behaviors. Nine types of Cu-IUDs were selected and incubated in simulated uterine fluid. They were paired for comparison based on the device properties and the release of cupric ion was determined by flame atomic absorption spectrometer for about 160 days. The result showed that there was a burst release during the first month and the release rate tends to slow down and become steady afterwards. In addition, the copper release was mainly influenced by frame, indomethacin and copper type (copper wire and copper sleeve) while the shape variation had little effect on copper release throughout the experiment. Moreover, the influence of copper surface area was only noticeable during the first month. These findings were seldom reported before and may provide some useful information for the design of Cu-IUDs.

  13. Complement activation by candidate biomaterials of an implantable microfabricated medical device.

    PubMed

    Sokolov, Andrey; Hellerud, Bernt C; Pharo, Anne; Johannessen, Erik A; Mollnes, Tom E

    2011-08-01

    Implantable devices realized by microfabrication have introduced a new class of potential biomaterials whose properties would need to be assessed. Such devices include sensors for measuring biological substances like glucose. Thus, 14 different candidate materials intended for design of such a device were investigated with respect to their complement activation potential in human serum. The fluid-phase activation was measured by the products C4d, Bb, C3bc, and the terminal complement complex (TCC), whereas solid-phase activation was measured by deposition of TCC on the material surfaces. No fluid-phase activation was found for materials related to the capsule, carrier, or sealing. Fluid-phase activation was, however, triggered to a various extent in three of the four nanoporous membranes (cellulose, polyamide, and aluminium oxide), whereas polycarbonate was rendered inactive. Solid-phase activation discriminated more sensitively between all the materials, revealing that the capsule candidate polydimethylsiloxane and sealing candidate silicone 3140 were highly compatible, showing significantly lower TCC deposition than the negative control (p < 0.01). Three of the candidate materials were indifferent, whereas the remaining nine showed significantly higher deposition of TCC than the negative control (p < 0.01). In conclusion, complement activation, in particular when examined on the solid phase, discriminated well between the different candidate materials tested and could be used as a guide for the selection of the best-suited materials for further investigation and development of the device.

  14. Active mode-locked lasers and other photonic devices using electro-optic whispering gallery mode resonators

    NASA Technical Reports Server (NTRS)

    Matsko, Andrey B. (Inventor); Ilchenko, Vladimir (Inventor); Savchenkov, Anatoliy (Inventor); Maleki, Lutfollah (Inventor)

    2006-01-01

    Techniques and devices using whispering gallery mode (WGM) optical resonators, where the optical materials of the WGM resonators exhibit an electro-optical effect to perform optical modulation. Examples of actively mode-locked lasers and other devices are described.

  15. Nanosilver on nanostructured silica: Antibacterial activity and Ag surface area

    PubMed Central

    Sotiriou, Georgios A.; Teleki, Alexandra; Camenzind, Adrian; Krumeich, Frank; Meyer, Andreas; Panke, Sven; Pratsinis, Sotiris E.

    2013-01-01

    Nanosilver is one of the first nanomaterials to be closely monitored by regulatory agencies worldwide motivating research to better understand the relationship between Ag characteristics and antibacterial activity. Nanosilver immobilized on nanostructured silica facilitates such investigations as the SiO2 support hinders the growth of nanosilver during its synthesis and, most importantly, its flocculation in bacterial suspensions. Here, such composite Ag/silica nanoparticles were made by flame spray pyrolysis of appropriate solutions of Ag-acetate or Ag-nitrate and hexamethyldisiloxane or tetraethylorthosilicate in ethanol, propanol, diethylene glucolmonobutyl ether, acetonitrile or ethylhexanoic acid. The effect of solution composition on nanosilver characteristics and antibacterial activity against the Gram negative Escherichia coli was investigated by monitoring their recombinantly synthesized green fluorescent protein. Suspensions with identical Ag mass concentration exhibited drastically different antibacterial activity pointing out that the nanosilver surface area concentration rather than its mass or molar or number concentration determine best its antibacterial activity. Nanosilver made from Ag-acetate showed a unimodal size distribution, while that made from inexpensive Ag-nitrate exhibited a bimodal one. Regardless of precursor composition or nanosilver size distribution, the antibacterial activity of nanosilver was correlated best with its surface area concentration in solution. PMID:23730198

  16. Nanosilver on nanostructured silica: Antibacterial activity and Ag surface area.

    PubMed

    Sotiriou, Georgios A; Teleki, Alexandra; Camenzind, Adrian; Krumeich, Frank; Meyer, Andreas; Panke, Sven; Pratsinis, Sotiris E

    2011-06-01

    Nanosilver is one of the first nanomaterials to be closely monitored by regulatory agencies worldwide motivating research to better understand the relationship between Ag characteristics and antibacterial activity. Nanosilver immobilized on nanostructured silica facilitates such investigations as the SiO2 support hinders the growth of nanosilver during its synthesis and, most importantly, its flocculation in bacterial suspensions. Here, such composite Ag/silica nanoparticles were made by flame spray pyrolysis of appropriate solutions of Ag-acetate or Ag-nitrate and hexamethyldisiloxane or tetraethylorthosilicate in ethanol, propanol, diethylene glucolmonobutyl ether, acetonitrile or ethylhexanoic acid. The effect of solution composition on nanosilver characteristics and antibacterial activity against the Gram negative Escherichia coli was investigated by monitoring their recombinantly synthesized green fluorescent protein. Suspensions with identical Ag mass concentration exhibited drastically different antibacterial activity pointing out that the nanosilver surface area concentration rather than its mass or molar or number concentration determine best its antibacterial activity. Nanosilver made from Ag-acetate showed a unimodal size distribution, while that made from inexpensive Ag-nitrate exhibited a bimodal one. Regardless of precursor composition or nanosilver size distribution, the antibacterial activity of nanosilver was correlated best with its surface area concentration in solution.

  17. First OSIRIS observations of active areas on comet 67P

    NASA Astrophysics Data System (ADS)

    Vincent, J.-B.; Sierks, H.; Oklay, N.; Agarwal, J.; Güttler, C.; Bodewits, D.; Osiris Team

    2014-04-01

    After a successful exit from hibernation, Rosetta started observing its final target comet 67P in March 2014 with the two OSIRIS cameras WAC and NAC (Wide Angle and Narrow Angle Camera) [1]. By the time of this conference, the spacecraft will have flown from 5 million to 50 km from the nucleus surface, reaching a resolution of 1 meter/pixel in the NAC images. During that period, the comet heliocentric distance varies from 4.3 to 3.2 AU and we will observe how the early activity develops. We know that cometary surfaces are not fully active; only a small fraction of the surface emits gas and dust. However we do not yet understand why it happens in that way, and what to expect on 67P. Recent publications using data from ground-based telescopes have proposed different interpretations for the distribution of active sources, from one to three at various latitudes [2, 3]. There is some evidence for different levels of activity in the northern and southern hemispheres, but these variations can only be constrained with close range data. In August 2014, OSIRIS will map the surface of the comet at high resolution, and perform weekly monitoring of the activity, especially the faintest jets. With these images and the inversion code COSSIM [4], we will be able to link observed features in the coma or on the limb to physical spots on the surface. On other comets visited by spacecrafts the activity has sometimes been associated with smooth areas, rough terrains, or specific morphologic features (cliff, crater, rim, . . . ). We will present a first look at how activity and terrain are linked on 67P, and look at variations of composition, morphology, or both. We will compare this identification of active areas to previous publications.

  18. THE EFFECT OF DOUBLE VERSUS SINGLE OSCILLATING EXERCISE DEVICES ON TRUNK AND LIMB MUSCLE ACTIVATION

    PubMed Central

    Arora, Shruti; Button, Duane C.; Basset, Fabien A.

    2013-01-01

    Purpose/Background: Proper strengthening of the core and upper extremities is important for muscular health, performance, and rehabilitation. Exercise devices have been developed that attempt to disrupt the center of gravity in order to activate the trunk stabilizing muscles. The objective of this study was to analyze the trunk and shoulder girdle muscle activation with double and single oscillating exercise devices (DOD and SOD respectively) in various planes. Methods: Twelve male subjects performed three interventions using both devices under randomized conditions: single-handed vertical orientation of DOD and SOD to produce 1) medio-lateral oscillation in the frontal plane 2) dorso-ventral oscillation in the sagittal plane and 3) single-handed horizontal orientation for superior and inferior oscillation in the transverse plane. Electromyographic (EMG) activity during the interventions of the anterior deltoid, triceps brachii, biceps brachii, forearm flexors as well as lower abdominal and back stabilizer muscles was collected, and were normalized to maximal voluntary contractions. A two way repeated measures ANOVA (2x3) was conducted to assess the influence of the devices and movement planes on muscle activation. Results: The DOD provided 35.9%, 40.8%, and 52.3% greater anterior deltoid, transverse abdominus (TA)/internal oblique (IO) and lumbo-sacral erector spinae (LSES) activation than did the SOD respectively. Effect size calculations revealed that these differences were of moderate to large magnitude (0.86, 0.48, and 0.61 respectively). There were no significant differences in muscular activation achieved between devices for the triceps brachii, biceps brachii and forearm flexor muscles. Exercise in the transverse plane resulted in 30.5%, 29.5%, and 19.5% greater activation than the sagittal and 21.8%, 17.2%, and 26.3% greater activation than the frontal plane for the anterior deltoid, TA/IO and LSES respectively. Conclusions: A DOD demonstrated greater

  19. Device and software used to carry out Cyclic Neutron Activation Analysis

    NASA Astrophysics Data System (ADS)

    Castro-García, M. P.; Rey-Ronco, M. A.; Alonso-Sánchez, T.

    2014-11-01

    This paper discusses the device and software used to carry out Cyclic Neutron Activation Analysis (CNAA). The aim of this investigation is defining through this device the fluorite content present on different samples from fluorspar concentration plant through the DGNAA (Delayed Gamma Neutron Activation Analysis) method. This device is made of americium-beryllium neutron source, NaI (2"×2") and BGO (2"×2") gamma rays detectors, multichannel and an automatic mechanism which moves the samples from activation and reading position. This mechanism is controlled by a software which allows moving the samples precisely and in a safe way (~ms), which it is very useful when the radioactive isotopes have to be detected with a half time less than 8s.

  20. Mobile health: a synopsis and comment on "Increasing physical activity with mobile devices: a meta-analysis".

    PubMed

    Johnston, Winter; Hoffman, Sara; Thornton, Louise

    2014-03-01

    We offer a synopsis and commentary on J. Fanning and colleagues' article "Increasing Physical Activity with Mobile Devices: A Meta-Analysis" published in the Journal of Medical Internet Research. Although regular physical activity has a range of benefits, very few adults in the USA meet recommended guidelines for daily physical activity. The meta-analysis of Fanning et al. (2012) aimed to synthesize the results of research using mobile devices to increase physical activity. Their review identified 11 studies that used mobile technologies, including short message service (SMS), apps, or personal digital assistant (PDA) to improve physical activity behaviors among participants. Fanning et al. conclude that while literature in this area is limited to date, there is initial support for the efficacy of mobile-based interventions for improving physical activity. Included studies varied greatly, and the majority used only SMS to influence physical behaviors, meaning generalization of results to other forms of mobile technologies may be premature. This review does, however, provide a foundation for understanding how mobile-based interventions may be used efficaciously for the development of future interventions to improve health behaviors.

  1. 24 Hours of Sleep, Sedentary Behavior, and Physical Activity with Nine Wearable Devices

    PubMed Central

    Rosenberger, Mary E.; Buman, Matthew P.; Haskell, William L.; McConnell, Michael V.; Carstensen, Laura L.

    2015-01-01

    Getting enough sleep, exercising and limiting sedentary activities can greatly contribute to disease prevention and overall health and longevity. Measuring the full 24-hour activity cycle - sleep, sedentary behavior (SED), light intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) - may now be feasible using small wearable devices. PURPOSE This study compares nine devices for accuracy in 24-hour activity measurement. METHODS Adults (N=40, 47% male) wore nine devices for 24-hours: Actigraph GT3X+, activPAL, Fitbit One, GENEactiv, Jawbone Up, LUMOback, Nike Fuelband, Omron pedometer, and Z-Machine. Comparisons (to standards) were made for total sleep time (Z-machine), time spent in SED (activPAL), LPA (GT3x+), MVPA (GT3x+), and steps (Omron). Analysis included mean absolute percent error, equivalence testing, and Bland-Altman plots. RESULTS Error rates ranged from 8.1–16.9% for sleep; 9.5–65.8% for SED; 19.7–28.0% for LPA; 51.8–92% for MVPA; and 14.1–29.9% for steps. Equivalence testing indicated only two comparisons were significantly equivalent to standards: the LUMOback for sedentary behavior and the GT3X+ for sleep. Bland-Altman plots indicated GT3X+ had the closest measurement for sleep, LUMOback for sedentary behavior, GENEactiv for LPA, Fitbit for MVPA and GT3X+ for steps. CONCLUSIONS Currently, no device accurately captures activity data across the entire 24-hour day, but the future of activity measurement should aim for accurate 24-hour measurement as a goal. Researchers should continue to select measurement devices based on their primary outcomes of interest. PMID:26484953

  2. Non-volatile memory devices with redox-active diruthenium molecular compound

    NASA Astrophysics Data System (ADS)

    Pookpanratana, S.; Zhu, H.; Bittle, E. G.; Natoli, S. N.; Ren, T.; Richter, C. A.; Li, Q.; Hacker, C. A.

    2016-03-01

    Reduction-oxidation (redox) active molecules hold potential for memory devices due to their many unique properties. We report the use of a novel diruthenium-based redox molecule incorporated into a non-volatile Flash-based memory device architecture. The memory capacitor device structure consists of a Pd/Al2O3/molecule/SiO2/Si structure. The bulky ruthenium redox molecule is attached to the surface by using a ‘click’ reaction and the monolayer structure is characterized by x-ray photoelectron spectroscopy to verify the Ru attachment and molecular density. The ‘click’ reaction is particularly advantageous for memory applications because of (1) ease of chemical design and synthesis, and (2) provides an additional spatial barrier between the oxide/silicon to the diruthenium molecule. Ultraviolet photoelectron spectroscopy data identified the energy of the electronic levels of the surface before and after surface modification. The molecular memory devices display an unsaturated charge storage window attributed to the intrinsic properties of the redox-active molecule. Our findings demonstrate the strengths and challenges with integrating molecular layers within solid-state devices, which will influence the future design of molecular memory devices.

  3. Active control of all-fibre graphene devices with electrical gating

    PubMed Central

    Lee, Eun Jung; Choi, Sun Young; Jeong, Hwanseong; Park, Nam Hun; Yim, Woongbin; Kim, Mi Hye; Park, Jae-Ku; Son, Suyeon; Bae, Sukang; Kim, Sang Jin; Lee, Kwanil; Ahn, Yeong Hwan; Ahn, Kwang Jun; Hong, Byung Hee; Park, Ji-Yong; Rotermund, Fabian; Yeom, Dong-Il

    2015-01-01

    Active manipulation of light in optical fibres has been extensively studied with great interest because of its compatibility with diverse fibre-optic systems. While graphene exhibits a strong electro-optic effect originating from its gapless Dirac-fermionic band structure, electric control of all-fibre graphene devices remains still highly challenging. Here we report electrically manipulable in-line graphene devices by integrating graphene-based field effect transistors on a side-polished fibre. Ion liquid used in the present work critically acts both as an efficient gating medium with wide electrochemical windows and transparent over-cladding facilitating light–matter interaction. Combined study of unique features in gate-variable electrical transport and optical transition at monolayer and randomly stacked multilayer graphene reveals that the device exhibits significant optical transmission change (>90%) with high efficiency-loss figure of merit. This subsequently modifies nonlinear saturable absorption characteristics of the device, enabling electrically tunable fibre laser at various operational regimes. The proposed device will open promising way for actively controlled optoelectronic and nonlinear photonic devices in all-fibre platform with greatly enhanced graphene–light interaction. PMID:25897687

  4. Active control of all-fibre graphene devices with electrical gating.

    PubMed

    Lee, Eun Jung; Choi, Sun Young; Jeong, Hwanseong; Park, Nam Hun; Yim, Woongbin; Kim, Mi Hye; Park, Jae-Ku; Son, Suyeon; Bae, Sukang; Kim, Sang Jin; Lee, Kwanil; Ahn, Yeong Hwan; Ahn, Kwang Jun; Hong, Byung Hee; Park, Ji-Yong; Rotermund, Fabian; Yeom, Dong-Il

    2015-04-21

    Active manipulation of light in optical fibres has been extensively studied with great interest because of its compatibility with diverse fibre-optic systems. While graphene exhibits a strong electro-optic effect originating from its gapless Dirac-fermionic band structure, electric control of all-fibre graphene devices remains still highly challenging. Here we report electrically manipulable in-line graphene devices by integrating graphene-based field effect transistors on a side-polished fibre. Ion liquid used in the present work critically acts both as an efficient gating medium with wide electrochemical windows and transparent over-cladding facilitating light-matter interaction. Combined study of unique features in gate-variable electrical transport and optical transition at monolayer and randomly stacked multilayer graphene reveals that the device exhibits significant optical transmission change (>90%) with high efficiency-loss figure of merit. This subsequently modifies nonlinear saturable absorption characteristics of the device, enabling electrically tunable fibre laser at various operational regimes. The proposed device will open promising way for actively controlled optoelectronic and nonlinear photonic devices in all-fibre platform with greatly enhanced graphene-light interaction.

  5. Non-volatile Memory Devices with Redox-active Diruthenium Molecular Compound

    PubMed Central

    Pookpanratana, S.; Zhu, H.; Bittle, E. G.; Natoli, S. N.; Ren, T.; Richter, C. A; Li, Q.; Hacker, C. A.

    2016-01-01

    Reduction-oxidation (redox) active molecules hold potential for memory devices due to their many unique properties. We report the use of a novel diruthenium-based redox molecule incorporated into a non-volatile Flash-based memory device architecture. The memory capacitor device structure consists of a Pd/Al2O3/molecule/SiO2/Si structure. The bulky ruthenium redox molecule is attached to the surface by using a “click” reaction and the monolayer structure is characterized by X-ray photoelectron spectroscopy to verify the Ru attachment and molecular density. The “click” reaction is particularly advantageous for memory applications because of (1) ease of chemical design and synthesis, and (2) provides an additional spatial barrier between the oxide/silicon to the diruthenium molecule. Ultraviolet photoelectron spectroscopy data identified the energy of the electronic levels of the surface before and after surface modification. The molecular memory devices display an unsaturated charge storage window attributed to the intrinsic properties of the redox-active molecule. Our findings demonstrate the strengths and challenges with integrating molecular layers within solid-state devices, which will influence the future design of molecular memory devices. PMID:26871549

  6. Human movement activity classification approaches that use wearable sensors and mobile devices

    NASA Astrophysics Data System (ADS)

    Kaghyan, Sahak; Sarukhanyan, Hakob; Akopian, David

    2013-03-01

    Cell phones and other mobile devices become part of human culture and change activity and lifestyle patterns. Mobile phone technology continuously evolves and incorporates more and more sensors for enabling advanced applications. Latest generations of smart phones incorporate GPS and WLAN location finding modules, vision cameras, microphones, accelerometers, temperature sensors etc. The availability of these sensors in mass-market communication devices creates exciting new opportunities for data mining applications. Particularly healthcare applications exploiting build-in sensors are very promising. This paper reviews different approaches of human activity recognition.

  7. Active packaging for topical cosmetic/drug products: a hot-melt extruded preservative delivery device.

    PubMed

    Zema, L; Sangalli, M E; Maroni, A; Foppoli, A; Bettero, A; Gazzaniga, A

    2010-06-01

    A delivery device intended for the prolonged release of antimicrobial agents, able to enhance the stability profile of liquid/semi-solid cosmetic/pharmaceutical products for topical application, was proposed in the present study. With the aid of a simulation program based on compartment models, the relevant kinetic and formulation parameters were defined using dehydroacetic acid sodium salt (DHA.Na, Prevan) as the model preservative. Indeed, the overall DHA.Na degradation rate is increased in the presence of formaldehyde releasers that are often employed as co-preservatives. Inert matrices (3 g weight and 18 mm diameter) based on high-density polyethylene (HDPE), possibly consistent with the design of an active packaging meant for preservative delivery, were prepared by hot-melt extrusion. Units with satisfactory physical-technological properties could be obtained up to 50%w/w loads of antimicrobial agent. In an attempt to modify the relevant Fickian release profiles by varying the area exposed to the medium, matrix systems coated with an impermeable film except for one base (CMs) or for the inner surface of a central drilled hole (PCMs) were investigated. On the basis of the n exponent of power equation and the outcome of linear fitting, PCMs were proven able to yield the zero-order release behaviour needed to ensure constant DHA.Na levels over a predetermined time period, as indicated by the simulation process.

  8. Active system area networks for data intensive computations. Final report

    SciTech Connect

    2002-04-01

    The goal of the Active System Area Networks (ASAN) project is to develop hardware and software technologies for the implementation of active system area networks (ASANs). The use of the term ''active'' refers to the ability of the network interfaces to perform application-specific as well as system level computations in addition to their traditional role of data transfer. This project adopts the view that the network infrastructure should be an active computational entity capable of supporting certain classes of computations that would otherwise be performed on the host CPUs. The result is a unique network-wide programming model where computations are dynamically placed within the host CPUs or the NIs depending upon the quality of service demands and network/CPU resource availability. The projects seeks to demonstrate that such an approach is a better match for data intensive network-based applications and that the advent of low-cost powerful embedded processors and configurable hardware makes such an approach economically viable and desirable.

  9. PECASE: Nanostructure Hybrid Organic/Inorganic Materials for Active Opto-Electronic Devices

    DTIC Science & Technology

    2011-01-03

    TFEL) devices already occupy a segment of the large-area, high-resolution, flat-panel-display market . The AC-TFEL displays, which consist of a...Noach, E. Z. Faraggi, G. Cohen, Y. Avny, R. Neumann, D. Davidov, and A. Lewis, Appl. Phys. Lett. 69, 3650 1996. 4P . F. Tian, P. E. Burrows, and S. R...stacked and patterned devices, one of the most feasible strategies for realizing RGB AC-EL displays is color filtering of white, ZnS-based phosphors.[1,2

  10. Science and Technology of Water Lifting Devices. Teaching of Science and Technology in Rural Areas.

    ERIC Educational Resources Information Center

    Rao, P. Ramachandra; Rao, N. R. Nagaraja

    Most science curriculum innovations seem to have their origins and emphases in urban intellectual concerns and their content generally caters to university bound students. The reason for the failure of rural students in science subjects may be the lack of relevancy of the program to the needs of individuals living in rural areas. Chapter 1 of this…

  11. Protected areas in tropical Africa: assessing threats and conservation activities.

    PubMed

    Tranquilli, Sandra; Abedi-Lartey, Michael; Abernethy, Katharine; Amsini, Fidèle; Asamoah, Augustus; Balangtaa, Cletus; Blake, Stephen; Bouanga, Estelle; Breuer, Thomas; Brncic, Terry M; Campbell, Geneviève; Chancellor, Rebecca; Chapman, Colin A; Davenport, Tim R B; Dunn, Andrew; Dupain, Jef; Ekobo, Atanga; Eno-Nku, Manasseh; Etoga, Gilles; Furuichi, Takeshi; Gatti, Sylvain; Ghiurghi, Andrea; Hashimoto, Chie; Hart, John A; Head, Josephine; Hega, Martin; Herbinger, Ilka; Hicks, Thurston C; Holbech, Lars H; Huijbregts, Bas; Kühl, Hjalmar S; Imong, Inaoyom; Yeno, Stephane Le-Duc; Linder, Joshua; Marshall, Phil; Lero, Peter Minasoma; Morgan, David; Mubalama, Leonard; N'Goran, Paul K; Nicholas, Aaron; Nixon, Stuart; Normand, Emmanuelle; Nziguyimpa, Leonidas; Nzooh-Dongmo, Zacharie; Ofori-Amanfo, Richard; Ogunjemite, Babafemi G; Petre, Charles-Albert; Rainey, Hugo J; Regnaut, Sebastien; Robinson, Orume; Rundus, Aaron; Sanz, Crickette M; Okon, David Tiku; Todd, Angelique; Warren, Ymke; Sommer, Volker

    2014-01-01

    Numerous protected areas (PAs) have been created in Africa to safeguard wildlife and other natural resources. However, significant threats from anthropogenic activities and decline of wildlife populations persist, while conservation efforts in most PAs are still minimal. We assessed the impact level of the most common threats to wildlife within PAs in tropical Africa and the relationship of conservation activities with threat impact level. We collated data on 98 PAs with tropical forest cover from 15 countries across West, Central and East Africa. For this, we assembled information about local threats as well as conservation activities from published and unpublished literature, and questionnaires sent to long-term field workers. We constructed general linear models to test the significance of specific conservation activities in relation to the threat impact level. Subsistence and commercial hunting were identified as the most common direct threats to wildlife and found to be most prevalent in West and Central Africa. Agriculture and logging represented the most common indirect threats, and were most prevalent in West Africa. We found that the long-term presence of conservation activities (such as law enforcement, research and tourism) was associated with lower threat impact levels. Our results highlight deficiencies in the management effectiveness of several PAs across tropical Africa, and conclude that PA management should invest more into conservation activities with long-term duration.

  12. Protected Areas in Tropical Africa: Assessing Threats and Conservation Activities

    PubMed Central

    Tranquilli, Sandra; Abedi-Lartey, Michael; Abernethy, Katharine; Amsini, Fidèle; Asamoah, Augustus; Balangtaa, Cletus; Blake, Stephen; Bouanga, Estelle; Breuer, Thomas; Brncic, Terry M.; Campbell, Geneviève; Chancellor, Rebecca; Chapman, Colin A.; Davenport, Tim R. B.; Dunn, Andrew; Dupain, Jef; Ekobo, Atanga; Eno-Nku, Manasseh; Etoga, Gilles; Furuichi, Takeshi; Gatti, Sylvain; Ghiurghi, Andrea; Hashimoto, Chie; Hart, John A.; Head, Josephine; Hega, Martin; Herbinger, Ilka; Hicks, Thurston C.; Holbech, Lars H.; Huijbregts, Bas; Kühl, Hjalmar S.; Imong, Inaoyom; Yeno, Stephane Le-Duc; Linder, Joshua; Marshall, Phil; Lero, Peter Minasoma; Morgan, David; Mubalama, Leonard; N'Goran, Paul K.; Nicholas, Aaron; Nixon, Stuart; Normand, Emmanuelle; Nziguyimpa, Leonidas; Nzooh-Dongmo, Zacharie; Ofori-Amanfo, Richard; Ogunjemite, Babafemi G.; Petre, Charles-Albert; Rainey, Hugo J.; Regnaut, Sebastien; Robinson, Orume; Rundus, Aaron; Sanz, Crickette M.; Okon, David Tiku; Todd, Angelique; Warren, Ymke; Sommer, Volker

    2014-01-01

    Numerous protected areas (PAs) have been created in Africa to safeguard wildlife and other natural resources. However, significant threats from anthropogenic activities and decline of wildlife populations persist, while conservation efforts in most PAs are still minimal. We assessed the impact level of the most common threats to wildlife within PAs in tropical Africa and the relationship of conservation activities with threat impact level. We collated data on 98 PAs with tropical forest cover from 15 countries across West, Central and East Africa. For this, we assembled information about local threats as well as conservation activities from published and unpublished literature, and questionnaires sent to long-term field workers. We constructed general linear models to test the significance of specific conservation activities in relation to the threat impact level. Subsistence and commercial hunting were identified as the most common direct threats to wildlife and found to be most prevalent in West and Central Africa. Agriculture and logging represented the most common indirect threats, and were most prevalent in West Africa. We found that the long-term presence of conservation activities (such as law enforcement, research and tourism) was associated with lower threat impact levels. Our results highlight deficiencies in the management effectiveness of several PAs across tropical Africa, and conclude that PA management should invest more into conservation activities with long-term duration. PMID:25469888

  13. Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices

    NASA Astrophysics Data System (ADS)

    Salem, Mohamed M. A.

    Controllable devices such as Magneto-Rheological Fluid Dampers, Electro-Rheological Dampers, and controllable friction devices have been studied extensively with limited implementation in real structures. Such devices have shown great potential in reducing seismic demands, either as smart base isolation systems, or as smart devices for multistory structures. Although variable stiffness devices can be used for seismic control of structures, the vast majority of research effort has been given to the control of damping. The primary focus of this dissertation is to evaluate the seismic control of structures using semi-active and passive variable stiffness characteristics. Smart base isolation systems employing variable stiffness devices have been studied, and two semi-active control strategies are proposed. The control algorithms were designed to reduce the superstructure and base accelerations of seismically isolated structures subject to near-fault and far-field ground motions. Computational simulations of the proposed control algorithms on the benchmark structure have shown that excessive base displacements associated with the near-fault ground motions may be better mitigated with the use of variable stiffness devices. However, the device properties must be controllable to produce a wide range of stiffness changes for an effective control of the base displacements. The potential of controllable stiffness devices in limiting the base displacement due to near-fault excitation without compromising the performance of conventionally isolated structures, is illustrated. The application of passive variable stiffness devices for seismic response mitigation of multistory structures is also investigated. A stiffening bracing system (SBS) is proposed to replace the conventional bracing systems of braced frames. An optimization process for the SBS parameters has been developed. The main objective of the design process is to maintain a uniform inter-story drift angle over the

  14. ILO activities in the area of chemical safety.

    PubMed

    Obadia, Isaac

    2003-08-21

    The ILO has been active in the area of safety in the use of chemicals at work since the year of its creation in 1919, including the development of international treaties and other technical instruments, the provision of technical assistance to its member States, and the development of chemical safety information systems. The two key ILO standards in this area are the Conventions on safety in the use of chemicals at work (No. 170, 1990), and the Prevention of Major Industrial Accidents (No. 174, 1993). The ILO Programme on occupational safety, health and environment (Safe Work) is currently responsible for ILO chemical safety activities. In the past two decades, most of ILO work in this area has been carried out within the context of inter-agency collaboration frameworks linking the ILO, WHO, UNEP, FAO, UNIDO, UNITAR, and the OECD, including the International Programme on Chemical Safety (IPCS), the Inter-Organisation Programme for the Sound Management of Chemicals (IOMC), and the Intergovernmental Forum on Chemical Safety (IFCS). Apart from the regular development, updating and dissemination of chemical safety information data bases such as the IPCS International Chemical Cards, the elaboration of a Globally harmonized system for the classification and labelling of Chemicals (GHS) has been the most outstanding achievement of this international collaboration on chemical safety.

  15. Shape memory alloy-based biopsy device for active locomotive intestinal capsule endoscope.

    PubMed

    Le, Viet Ha; Hernando, Leon-Rodriguez; Lee, Cheong; Choi, Hyunchul; Jin, Zhen; Nguyen, Kim Tien; Go, Gwangjun; Ko, Seong-Young; Park, Jong-Oh; Park, Sukho

    2015-03-01

    Recently, capsule endoscopes have been used for diagnosis in digestive organs. However, because a capsule endoscope does not have a locomotive function, its use has been limited to small tubular digestive organs, such as small intestine and esophagus. To address this problem, researchers have begun studying an active locomotive intestine capsule endoscope as a medical instrument for the whole gastrointestinal tract. We have developed a capsule endoscope with a small permanent magnet that is actuated by an electromagnetic actuation system, allowing active and flexible movement in the patient's gut environment. In addition, researchers have noted the need for a biopsy function in capsule endoscope for the definitive diagnosis of digestive diseases. Therefore, this paper proposes a novel robotic biopsy device for active locomotive intestine capsule endoscope. The proposed biopsy device has a sharp blade connected with a shape memory alloy actuator. The biopsy device measuring 12 mm in diameter and 3 mm in length was integrated into our capsule endoscope prototype, where the device's sharp blade was activated and exposed by the shape memory alloy actuator. Then the electromagnetic actuation system generated a specific motion of the capsule endoscope to extract the tissue sample from the intestines. The final biopsy sample tissue had a volume of about 6 mm(3), which is a sufficient amount for a histological analysis. Consequently, we proposed the working principle of the biopsy device and conducted an in-vitro biopsy test to verify the feasibility of the biopsy device integrated into the capsule endoscope prototype using the electro-magnetic actuation system.

  16. Multi-Sensor Fusion for Enhanced Contextual Awareness of Everyday Activities with Ubiquitous Devices

    PubMed Central

    Guiry, John J.; van de Ven, Pepijn; Nelson, John

    2014-01-01

    In this paper, the authors investigate the role that smart devices, including smartphones and smartwatches, can play in identifying activities of daily living. A feasibility study involving N = 10 participants was carried out to evaluate the devices' ability to differentiate between nine everyday activities. The activities examined include walking, running, cycling, standing, sitting, elevator ascents, elevator descents, stair ascents and stair descents. The authors also evaluated the ability of these devices to differentiate indoors from outdoors, with the aim of enhancing contextual awareness. Data from this study was used to train and test five well known machine learning algorithms: C4.5, CART, Naïve Bayes, Multi-Layer Perceptrons and finally Support Vector Machines. Both single and multi-sensor approaches were examined to better understand the role each sensor in the device can play in unobtrusive activity recognition. The authors found overall results to be promising, with some models correctly classifying up to 100% of all instances. PMID:24662406

  17. 75 FR 61494 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... HUMAN SERVICES Food and Drug Administration Agency Information Collection Activities; Proposed... Symbols on Labels and in Labeling of In Vitro Diagnostic Devices Intended for Professional Use AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA)...

  18. Activated T lymphocytes migrate toward the cathode of DC electric fields in microfluidic devices.

    PubMed

    Li, Jing; Nandagopal, Saravanan; Wu, Dan; Romanuik, Sean F; Paul, Kausik; Thomson, Douglas J; Lin, Francis

    2011-04-07

    Immune cell migration is a fundamental process that enables immunosurveillance and immune responses. Understanding the mechanism of immune cell migration is not only of importance to the biology of cells, but also has high relevance to cell trafficking mediated physiological processes and diseases such as embryogenesis, wound healing, autoimmune diseases and cancers. In addition to the well-known chemical concentration gradient based guiding mechanism (i.e. chemotaxis), recent studies have shown that lymphocytes can respond to applied physiologically relevant direct current (DC) electric fields by migrating toward the cathode of the fields (i.e. electrotaxis) in both in vitro and in vivo settings. In the present study, we employed two microfluidic devices allowing controlled application of electric fields inside the microfluidic channel for quantitative studies of lymphocyte electrotaxis in vitro at the single cell level. The first device is fabricated by soft-lithography and the second device is made in glass with integrated on-chip electrodes. Using both devices, we for the first time showed that anti-CD3/CD28 antibodies activated human blood T cells migrate to the cathode of the applied DC electric field. This finding is consistent with previous electrotaxis studies on other lymphocyte subsets suggesting electrotaxis is a novel guiding mechanism for immune cell migration. Furthermore, the characteristics of electrotaxis and chemotaxis of activated T cells in PDMS microfluidic devices are compared.

  19. The Timing of Noise-Sensitive Activities in Residential Areas

    NASA Technical Reports Server (NTRS)

    Fields, J. M.

    1985-01-01

    Data from a nationally representative survey of time use was analyzed to provide estimates of the percentage of the population which is engaged in noise sensitive activities during each hour of the day on weekdays, Fridays, Saturdays and Sundays. Estimates are provided of the percentage engaged in aural communication activities at home, sleeping at home, or simply at home. The day can be roughly divided into four noise sensitivity periods consisting of two relatively steady state periods, night and day and the early morning and evening transition periods. Weekends differ from weekdays in that the morning transition period is one hour later and the numbers of people engaged in aural communication during the day at home are approximately one-half to three-quarters greater. The extent and timing of noise sensitive activities was found to be similiar for all parts of the United States, for different sizes of urban areas, and for the three seasons surveyed (September through May). The timing of activity periods does not differ greatly by sex or age even though women and people over 65 are much more likely to be at home during the daytime.

  20. Urban area navigation using active millimeter-wave radar

    NASA Astrophysics Data System (ADS)

    Corken, Richard A.; Evans, Michael A.

    2002-08-01

    An active MilliMeter Wave (MMW) system exploiting forward squinting Synthetic Aperture Radar (SAR) techniques can provide high resolution imagery. Such a radar offers a compact, all weather, day/night solution to the problem of accurate airborne navigation. Interpreting radar imagery of very cluttered urban areas is challenging, thus complicating autonomous navigation within such areas. For example, imagery is subject to effects such as layover distortions due to the height of buildings and also considerable radar shadowing. In this paper we examine the use of synthetic imagery to capture the key elements of the radar imagery. The MMW imagery can then be related to the physical models from which the synthetic imagery is generated leading to improved scene understanding. This paper describes the modeling process adopted and compares real imagery from a 35GHz forward squinting SAR radar with the synthetically generated imagery. The modeling process includes provision for terrain undulation, man-made and natural clutter regions and the ability to generate a sequence of imagery from a specified flight path. Examples presented include a representative urban area containing a variety of building structures. An important part of this research is the required fidelity of the synthetic scene model and therefore investigations into the level of detail required are also presented. Further work aims to exploit the synthetic imagery for navigational purposes through registration with the actual radar image thereby automatically locating key building structures with the imagery.

  1. Large area flexible SERS active substrates using engineered nanostructures

    NASA Astrophysics Data System (ADS)

    Chung, Aram J.; Huh, Yun Suk; Erickson, David

    2011-07-01

    Surface enhanced Raman scattering (SERS) is an analytical sensing method that provides label-free detection, molecularly specific information, and extremely high sensitivity. The Raman enhancement that makes this method attractive is mainly attributed to the local amplification of the incident electromagnetic field that occurs when a surface plasmon mode is excited at a metallic nanostructure. Here, we present a simple, cost effective method for creating flexible, large area SERS-active substrates using a new technique we call shadow mask assisted evaporation (SMAE). The advantage of large, flexible SERS substrates such as these is they have more area for multiplexing and can be incorporated into irregular surfaces such as clothing. We demonstrate the formation of four different types of nanostructure arrays (pillar, nib, ellipsoidal cylinder, and triangular tip) by controlling the evaporation angle, substrate rotation, and deposition rate of metals onto anodized alumina nanoporous membranes as large as 27 mm. In addition, we present experimental results showing how a hybrid structure comprising of gold nanospheres embedded in a silver nano-pillar structure can be used to obtain a 50× SERS enhancement over the raw nanoparticles themselves.Surface enhanced Raman scattering (SERS) is an analytical sensing method that provides label-free detection, molecularly specific information, and extremely high sensitivity. The Raman enhancement that makes this method attractive is mainly attributed to the local amplification of the incident electromagnetic field that occurs when a surface plasmon mode is excited at a metallic nanostructure. Here, we present a simple, cost effective method for creating flexible, large area SERS-active substrates using a new technique we call shadow mask assisted evaporation (SMAE). The advantage of large, flexible SERS substrates such as these is they have more area for multiplexing and can be incorporated into irregular surfaces such as

  2. Air-cathode microbial fuel cell array: a device for identifying and characterizing electrochemically active microbes.

    PubMed

    Hou, Huijie; Li, Lei; de Figueiredo, Paul; Han, Arum

    2011-01-15

    Microbial fuel cells (MFCs) have generated excitement in environmental and bioenergy communities due to their potential for coupling wastewater treatment with energy generation and powering diverse devices. The pursuit of strategies such as improving microbial cultivation practices and optimizing MFC devices has increased power generating capacities of MFCs. However, surprisingly few microbial species with electrochemical activity in MFCs have been identified because current devices do not support parallel analyses or high throughput screening. We have recently demonstrated the feasibility of using advanced microfabrication methods to fabricate an MFC microarray. Here, we extend these studies by demonstrating a microfabricated air-cathode MFC array system. The system contains 24 individual air-cathode MFCs integrated onto a single chip. The device enables the direct and parallel comparison of different microbes loaded onto the array. Environmental samples were used to validate the utility of the air-cathode MFC array system and two previously identified isolates, 7Ca (Shewanella sp.) and 3C (Arthrobacter sp.), were shown to display enhanced electrochemical activities of 2.69 mW/m(2) and 1.86 mW/m(2), respectively. Experiments using a large scale conventional air-cathode MFC validated these findings. The parallel air-cathode MFC array system demonstrated here is expected to promote and accelerate the discovery and characterization of electrochemically active microbes.

  3. Characterization of Personal Privacy Devices (PPD) radiation pattern impact on the ground and airborne segments of the local area augmentation system (LAAS) at GPS L1 frequency

    NASA Astrophysics Data System (ADS)

    Alkhateeb, Abualkair M. Khair

    Personal Privacy Devices (PPDs) are radio-frequency transmitters that intentionally transmit in a frequency band used by other devices for the intent purpose of denying service to those devices. These devices have shown the potential to interfere with the ground and air sub-systems of the Local Area Augmentation Systems (LAAS), a GPS-based navigation aids at commercial airports. The Federal Aviation Administration (FAA) is concerned by the potential impact of these devices to GPS navigation aids at airports and has commenced an activity to determine the severity of this threat. In support of this situation, the research in this dissertation has been conducted under (FAA) Cooperative Agreement 2011-G-012, to investigate the impact of these devices on the LAAS. In order to investigate the impact of PPDs Radio Frequency Interference (RFI) on the ground and air sub-systems of the LAAS, the work presented in phase one of this research is intended to characterize the vehicle's impact on the PPD's Effective Isotropic Radiated Power (EIRP). A study was conceived in this research to characterize PPD performance by examining the on-vehicle radiation patterns as a function of vehicle type, jammer type, jammer location inside a vehicle and jammer orientation at each location. Phase two was to characterize the GPS Radiation Pattern on Multipath Limiting Antenna. MLA has to meet stringent requirements for acceptable signal detection and multipath rejection. The ARL-2100 is the most recent MLA antenna proposed to be used in the LAAS ground segment. The ground-based antenna's radiation pattern was modeled. This was achieved via (HFSS) a commercial-off the shelf CAD-based modeling code with a full-wave electromagnetic software simulation package that uses the Finite Element Analysis. Phase three of this work has been conducted to study the characteristics of the GPS Radiation Pattern on Commercial Aircraft. The airborne GPS antenna was modeled and the resulting radiation pattern on

  4. Properties of nanosheets of 2D-borocarbonitrides related to energy devices, transistors and other areas

    NASA Astrophysics Data System (ADS)

    Sreedhara, M. B.; Gopalakrishnan, K.; Bharath, B.; Kumar, Ram; Kulkarni, G. U.; Rao, C. N. R.

    2016-07-01

    We have prepared borocarbonitrides of various compositions with extended sheet morphology, by the reaction of few-layer graphene with boric acid and urea at 900 °C and characterized them in detail. Supercapacitor performance of the borocarbonitrides has been studied in detail, the composition containing more pyridinc nitrogen exhibiting a specific capacitance of 306 F/g at 0.2 A/g. This composition also shows good oxygen reduction reaction (ORR) activity with an electron transfer number close to 4. The extended sheet structures of the BxCyNz samples has enabled us to fabricate field-effect transistors. These materials also show reasonable UV photoresponse.

  5. Devices for Self-Monitoring Sedentary Time or Physical Activity: A Scoping Review

    PubMed Central

    Loveday, Adam; Pearson, Natalie; Edwardson, Charlotte; Yates, Thomas; Biddle, Stuart JH; Esliger, Dale W

    2016-01-01

    Background It is well documented that meeting the guideline levels (150 minutes per week) of moderate-to-vigorous physical activity (PA) is protective against chronic disease. Conversely, emerging evidence indicates the deleterious effects of prolonged sitting. Therefore, there is a need to change both behaviors. Self-monitoring of behavior is one of the most robust behavior-change techniques available. The growing number of technologies in the consumer electronics sector provides a unique opportunity for individuals to self-monitor their behavior. Objective The aim of this study is to review the characteristics and measurement properties of currently available self-monitoring devices for sedentary time and/or PA. Methods To identify technologies, four scientific databases were systematically searched using key terms related to behavior, measurement, and population. Articles published through October 2015 were identified. To identify technologies from the consumer electronic sector, systematic searches of three Internet search engines were also performed through to October 1, 2015. Results The initial database searches identified 46 devices and the Internet search engines identified 100 devices yielding a total of 146 technologies. Of these, 64 were further removed because they were currently unavailable for purchase or there was no evidence that they were designed for, had been used in, or could readily be modified for self-monitoring purposes. The remaining 82 technologies were included in this review (73 devices self-monitored PA, 9 devices self-monitored sedentary time). Of the 82 devices included, this review identified no published articles in which these devices were used for the purpose of self-monitoring PA and/or sedentary behavior; however, a number of technologies were found via Internet searches that matched the criteria for self-monitoring and provided immediate feedback on PA (ActiGraph Link, Microsoft Band, and Garmin Vivofit) and sedentary time

  6. A passive-flow microfluidic device for imaging latent HIV activation dynamics in single T cells

    PubMed Central

    Gearhart, Larisa M.; Miller-Jensen, Kathryn

    2015-01-01

    Quantifying cell-to-cell variability in drug response dynamics is important when evaluating therapeutic efficacy. For example, optimizing latency reversing agents (LRAs) for use in a clinical “activate-and-kill” strategy to purge the latent HIV reservoir in patients requires minimizing heterogeneous viral activation dynamics. To evaluate how heterogeneity in latent HIV activation varies across a range of LRAs, we tracked drug-induced response dynamics in single cells via live-cell imaging using a latent HIV–GFP reporter virus in a clonal Jurkat T cell line. To enable these studies in suspension cells, we designed a simple method to capture an array of single Jurkat T cells using a passive-flow microfluidic device. Our device, which does not require external pumps or tubing, can trap hundreds of cells within minutes with a high retention rate over 12 hours of imaging. Using this device, we quantified heterogeneity in viral activation stimulated by transcription factor (TF) activators and histone deacetylase (HDAC) inhibitors. Generally, TF activators resulted in both faster onset of viral activation and faster rates of production, while HDAC inhibitors resulted in more uniform onset times, but more heterogeneous rates of production. Finally, we demonstrated that while onset time of viral gene expression and rate of viral production together predict total HIV activation, rate and onset time were not correlated within the same individual cell, suggesting that these features are regulated independently. Overall, our results reveal drug-specific patterns of noisy HIV activation dynamics not previously identified in static single-cell assays, which may require consideration for the most effective activate-and-kill regime. PMID:26138068

  7. A passive-flow microfluidic device for imaging latent HIV activation dynamics in single T cells.

    PubMed

    Ramji, Ramesh; Wong, Victor C; Chavali, Arvind K; Gearhart, Larisa M; Miller-Jensen, Kathryn

    2015-09-01

    Quantifying cell-to-cell variability in drug response dynamics is important when evaluating therapeutic efficacy. For example, optimizing latency reversing agents (LRAs) for use in a clinical "activate-and-kill" strategy to purge the latent HIV reservoir in patients requires minimizing heterogeneous viral activation dynamics. To evaluate how heterogeneity in latent HIV activation varies across a range of LRAs, we tracked drug-induced response dynamics in single cells via live-cell imaging using a latent HIV-GFP reporter virus in a clonal Jurkat T cell line. To enable these studies in suspension cells, we designed a simple method to capture an array of single Jurkat T cells using a passive-flow microfluidic device. Our device, which does not require external pumps or tubing, can trap hundreds of cells within minutes with a high retention rate over 12 hours of imaging. Using this device, we quantified heterogeneity in viral activation stimulated by transcription factor (TF) activators and histone deacetylase (HDAC) inhibitors. Generally, TF activators resulted in both faster onset of viral activation and faster rates of production, while HDAC inhibitors resulted in more uniform onset times, but more heterogeneous rates of production. Finally, we demonstrated that while onset time of viral gene expression and rate of viral production together predict total HIV activation, rate and onset time were not correlated within the same individual cell, suggesting that these features are regulated independently. Overall, our results reveal drug-specific patterns of noisy HIV activation dynamics not previously identified in static single-cell assays, which may require consideration for the most effective activate-and-kill regime.

  8. Physical Modeling of Activation Energy in Organic Semiconductor Devices based on Energy and Momentum Conservations.

    PubMed

    Mao, Ling-Feng; Ning, H; Hu, Changjun; Lu, Zhaolin; Wang, Gaofeng

    2016-04-22

    Field effect mobility in an organic device is determined by the activation energy. A new physical model of the activation energy is proposed by virtue of the energy and momentum conservation equations. The dependencies of the activation energy on the gate voltage and the drain voltage, which were observed in the experiments in the previous independent literature, can be well explained using the proposed model. Moreover, the expression in the proposed model, which has clear physical meanings in all parameters, can have the same mathematical form as the well-known Meyer-Neldel relation, which lacks of clear physical meanings in some of its parameters since it is a phenomenological model. Thus it not only describes a physical mechanism but also offers a possibility to design the next generation of high-performance optoelectronics and integrated flexible circuits by optimizing device physical parameter.

  9. Physical Modeling of Activation Energy in Organic Semiconductor Devices based on Energy and Momentum Conservations

    PubMed Central

    Mao, Ling-Feng; Ning, H.; Hu, Changjun; Lu, Zhaolin; Wang, Gaofeng

    2016-01-01

    Field effect mobility in an organic device is determined by the activation energy. A new physical model of the activation energy is proposed by virtue of the energy and momentum conservation equations. The dependencies of the activation energy on the gate voltage and the drain voltage, which were observed in the experiments in the previous independent literature, can be well explained using the proposed model. Moreover, the expression in the proposed model, which has clear physical meanings in all parameters, can have the same mathematical form as the well-known Meyer-Neldel relation, which lacks of clear physical meanings in some of its parameters since it is a phenomenological model. Thus it not only describes a physical mechanism but also offers a possibility to design the next generation of high-performance optoelectronics and integrated flexible circuits by optimizing device physical parameter. PMID:27103586

  10. Physical Modeling of Activation Energy in Organic Semiconductor Devices based on Energy and Momentum Conservations

    NASA Astrophysics Data System (ADS)

    Mao, Ling-Feng; Ning, H.; Hu, Changjun; Lu, Zhaolin; Wang, Gaofeng

    2016-04-01

    Field effect mobility in an organic device is determined by the activation energy. A new physical model of the activation energy is proposed by virtue of the energy and momentum conservation equations. The dependencies of the activation energy on the gate voltage and the drain voltage, which were observed in the experiments in the previous independent literature, can be well explained using the proposed model. Moreover, the expression in the proposed model, which has clear physical meanings in all parameters, can have the same mathematical form as the well-known Meyer-Neldel relation, which lacks of clear physical meanings in some of its parameters since it is a phenomenological model. Thus it not only describes a physical mechanism but also offers a possibility to design the next generation of high-performance optoelectronics and integrated flexible circuits by optimizing device physical parameter.

  11. Laboratory demonstration model: Active cleaning technique device. [for removal of contaminants from an optical surface

    NASA Technical Reports Server (NTRS)

    Shannon, R. L.; Gillette, R. B.

    1974-01-01

    The technique which utilizes exposure to a plasma to remove contaminants from a surface was incorporated into a laboratory model which demonstrates active cleaning by both plasma cleaning and ion sputtering modes of operation. The development phase is reported and includes discussion of the plasma tube configuration, device design, and performance tests. A general description of the active cleaning device is provided which includes information on the main power/plasma discharge sensors, and the power, gas supply, and ion accelerator systems. Development of the active cleaning species at high vacuum conditions is described and results indicate that plasma cleaning occurs in the region of a visible plume which extends from the end of the plasma tube. Recommendations are made for research to determine the plasma cleaning mechanism and the plasma species responsible for the cleaning, as well limitations on the type of contaminants that can be removed.

  12. Microfluidic Emulation of Mechanical Circulatory Support Device Shear-Mediated Platelet Activation

    PubMed Central

    Dimasi, A.; Rasponi, M.; Sheriff, J.; Chiu, W.-C.; Bluestein, D.; Tran, P.L.; Slepian, M. J.; Redaelli, A.

    2016-01-01

    Thrombosis of ventricular assist devices (VADs) compromises their performance, with associated risks of systemic embolization, stroke, pump stop and possible death. Anti-thrombotic (AT) drugs, utilized to limit thrombosis, are largely dosed empirically, with limited testing of their efficacy. Further, such testing, if performed, typically examines efficacy under static conditions, which is not reflective of actual shear-mediated flow. Here we adopted our previously developed Device Thrombogenicity Emulation methodology to design microfluidic platforms able to emulate representative shear stress profiles of mechanical circulatory support (MCS) devices. Our long-term goal is to utilize these systems for point-of-care (POC) personalized testing of AT efficacy under specific, individual shear profiles. First, we designed different types of microfluidic channels able to replicate sample shear stress patterns observed in MCS devices. Second, we explored the flexibility of microfluidic technology in generating dynamic shear stress profiles by modulating the geometrical features of the channels. Finally, we designed microfluidic channel systems able to emulate the shear stress profiles of two commercial VADs. From CFD analyses, the VAD-emulating microfluidic systems were able to replicate the main characteristics of the shear stress waveforms of the macroscale VADs (i.e. shear stress peaks and duration). Our results establish the basis for development of a lab-on-chip POC system able to perform device-specific and patient-specific platelet activation state assays. PMID:26578003

  13. Semi-active control of helicopter vibration using controllable stiffness and damping devices

    NASA Astrophysics Data System (ADS)

    Anusonti-Inthra, Phuriwat

    Semi-active concepts for helicopter vibration reduction are developed and evaluated in this dissertation. Semi-active devices, controllable stiffness devices or controllable orifice dampers, are introduced; (i) in the blade root region (rotor-based concept) and (ii) between the rotor and the fuselage as semi-active isolators (in the non-rotating frame). Corresponding semi-active controllers for helicopter vibration reduction are also developed. The effectiveness of the rotor-based semi-active vibration reduction concept (using stiffness and damping variation) is demonstrated for a 4-bladed hingeless rotor helicopter in moderate- to high-speed forward flight. A sensitivity study shows that the stiffness variation of root element can reduce hub vibrations when proper amplitude and phase are used. Furthermore, the optimal semi-active control scheme can determine the combination of stiffness variations that produce significant vibration reduction in all components of vibratory hub loads simultaneously. It is demonstrated that desired cyclic variations in properties of the blade root region can be practically achieved using discrete controllable stiffness devices and controllable dampers, especially in the flap and lag directions. These discrete controllable devices can produce 35--50% reduction in a composite vibration index representing all components of vibratory hub loads. No detrimental increases are observed in the lower harmonics of blade loads and blade response (which contribute to the dynamic stresses) and controllable device internal loads, when the optimal stiffness and damping variations are introduced. The effectiveness of optimal stiffness and damping variations in reducing hub vibration is retained over a range of cruise speeds and for variations in fundamental rotor properties. The effectiveness of the semi-active isolator is demonstrated for a simplified single degree of freedom system representing the semi-active isolation system. The rotor

  14. A comparative study of the bactericidal activity and daily disinfection housekeeping surfaces by a new portable pulsed UV radiation device.

    PubMed

    Umezawa, Kazuo; Asai, Satomi; Inokuchi, Sadaki; Miyachi, Hayato

    2012-06-01

    Daily cleaning and disinfecting of non-critical surfaces in the patient-care areas are known to reduce the occurrence of health care-associated infections. However, the conventional means for decontamination of housekeeping surfaces of sites of frequent hand contact such as manual disinfection using ethanol wipes are laborious and time-consuming in daily practice. This study evaluated a newly developed portable pulsed ultraviolet (UV) radiation device for its bactericidal activity in comparison with continuous UV-C, and investigated its effect on the labor burden when implemented in a hospital ward. Pseudomonas aeruginosa, Multidrug-resistant P. aeruginosa, Escherichia coli, Acinetobacter baumannii, Amikacin and Ciprofloxacin-resistant A. baumannii, Staphylococcus aureus, Methicillin-resistant S. aureus and Bacillus cereus were irradiated with pulsed UV or continuous UV-C. Pulsed UV and continuous UV-C required 5 and 30 s of irradiation, respectively, to attain bactericidal activity with more than 2Log growth inhibition of all the species. The use of pulsed UV in daily disinfection of housekeeping surfaces reduced the working hours by half in comparison to manual disinfection using ethanol wipes. The new portable pulsed UV radiation device was proven to have a bactericidal activity against critical nosocomial bacteria, including antimicrobial-resistant bacteria after short irradiation, and was thus found to be practical as a method for disinfecting housekeeping surfaces and decreasing the labor burden.

  15. Methods, microfluidic devices, and systems for detection of an active enzymatic agent

    DOEpatents

    Sommer, Gregory J; Hatch, Anson V; Singh, Anup K; Wang, Ying-Chih

    2014-10-28

    Embodiments of the present invention provide methods, microfluidic devices, and systems for the detection of an active target agent in a fluid sample. A substrate molecule is used that contains a sequence which may cleave in the presence of an active target agent. A SNAP25 sequence is described, for example, that may be cleaved in the presence of Botulinum Neurotoxin. The substrate molecule includes a reporter moiety. The substrate molecule is exposed to the sample, and resulting reaction products separated using electrophoretic separation. The elution time of the reporter moiety may be utilized to identify the presence or absence of the active target agent.

  16. Safety Design Requirements for Active Hazard Mitigation Device (AHMD) Employed to Address Fast and Slow Cook-off Thermal Threats

    DTIC Science & Technology

    2014-12-18

    Hazard Mitigation Device (AHMD) Employed to Address Fast and Slow Cook-off Thermal Threats 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...environments. 15. SUBJECT TERMS Active Hazard Mitigation Device insensitive munitions fast cook-off slow...DESIGN REQUIREMENTS FOR ACTIVE HAZARD MITIGATION DEVICE (AHMD) EMPLOYED TO ADDRESS FAST AND SLOW COOK-OFF THERMAL THREATS DOD Fuze Engineering

  17. Dry etching techniques for active devices based on hexagonal boron nitride epilayers

    SciTech Connect

    Grenadier, Samuel; Li, Jing; Lin, Jingyu; Jiang, Hongxing

    2013-11-15

    Hexagonal boron nitride (hBN) has emerged as a fundamentally and technologically important material system owing to its unique physical properties including layered structure, wide energy bandgap, large optical absorption, and neutron capture cross section. As for any materials under development, it is necessary to establish device processing techniques to realize active devices based on hBN. The authors report on the advancements in dry etching techniques for active devices based on hBN epilayers via inductively coupled plasma (ICP). The effect of ICP radio frequency (RF) power on the etch rate and vertical side wall profile was studied. The etching depth and angle with respect to the surface were measured using atomic force microscopy showing that an etching rate ∼1.25 μm/min and etching angles >80° were obtained. Profilometer data and scanning electron microscope images confirmed these results. This work demonstrates that SF{sub 6} is very suitable for etching hBN epilayers in RF plasma environments and can serve as a guide for future hBN device processing.

  18. Photovoltaic performance of block copolymer devices is independent of the crystalline texture in the active layer

    DOE PAGES

    Guo, Changhe; Lee, Youngmin; Lin, Yen -Hao; ...

    2016-06-15

    The electronic properties of organic semiconductors are strongly influenced by intermolecular packing. When cast as thin films, crystalline π-conjugated molecules are strongly textured, potentially leading to anisotropic charge transport. Consequently, it is hypothesized that the orientation of crystallites in the active layer plays an important role in charge extraction and organic photovoltaic device performance. Here we demonstrate orientation control of molecular packing from mostly face-on to edge-on configurations in the active layer of P3HT-b-PFTBT block copolymer photovoltaics using 1-chloronaphthalene as a solvent additive. The effect of molecular orientations in P3HT crystals on charge transport and solar cell performance is examined.more » We find that optimized photovoltaic device performance is independent of the crystalline texture of P3HT. Our observations provide further insights into the molecular organization required for efficient charge transport and overall device efficiencies. That is, the dominant crystal orientation, whether face-on or edge-on, is not critical to organic solar cells. Furthermore, a broad distribution of crystallite orientations ensures pathways for charge transport in any direction and enables efficient charge extraction in photovoltaic devices.« less

  19. Photovoltaic performance of block copolymer devices is independent of the crystalline texture in the active layer

    SciTech Connect

    Guo, Changhe; Lee, Youngmin; Lin, Yen -Hao; Strzalka, Joseph; Wang, Cheng; Hexemer, Alexander; Jaye, Cherno; Fischer, Daniel A.; Verduzco, Rafael; Wang, Qing; Gomez, Enrique D.

    2016-06-15

    The electronic properties of organic semiconductors are strongly influenced by intermolecular packing. When cast as thin films, crystalline π-conjugated molecules are strongly textured, potentially leading to anisotropic charge transport. Consequently, it is hypothesized that the orientation of crystallites in the active layer plays an important role in charge extraction and organic photovoltaic device performance. Here we demonstrate orientation control of molecular packing from mostly face-on to edge-on configurations in the active layer of P3HT-b-PFTBT block copolymer photovoltaics using 1-chloronaphthalene as a solvent additive. The effect of molecular orientations in P3HT crystals on charge transport and solar cell performance is examined. We find that optimized photovoltaic device performance is independent of the crystalline texture of P3HT. Our observations provide further insights into the molecular organization required for efficient charge transport and overall device efficiencies. That is, the dominant crystal orientation, whether face-on or edge-on, is not critical to organic solar cells. Furthermore, a broad distribution of crystallite orientations ensures pathways for charge transport in any direction and enables efficient charge extraction in photovoltaic devices.

  20. Focused-ion-beam post-processing technology for active devices

    NASA Astrophysics Data System (ADS)

    Tee, Chyng Wen; Lau, Fat Kit; Zhao, Xin; Penty, Richard; White, Ian

    2006-09-01

    Focused ion beam (FIB) etching technology is a highly efficient post-processing technique with the functionality to perform sputter etching and deposition of metals or insulators by means of a computer-generated mask. The high resolution and the ability to remove material directly from the sample in-situ make FIB etching the ideal candidate for device prototyping of novel micro-size photonic component design. Furthermore, the fact that arbitrary profile can be etched directly onto a sample without the need to prepare conventional mask and photolithography process makes novel device research with rapid feedback from characterisation to design activities possible. In this paper, we present a concise summary of the research work in Cambridge based on FIB technology. We demonstrate the applicability of focussed ion beam post processing technology to active photonic devices research. Applications include the integration of advanced waveguide architectures onto active photonic components. We documents details on the integration of lens structure on tapered lasers, photonic crystals on active SOA-integrated waveguides and surface profiling of low-cost gain-guided vertical-cavity surface-emitting lasers. Furthermore, we discuss additional functions of FIB in the measurement of buried waveguide structures or the integration of total-internal-reflection (TIR) mirror in optical interconnect structures.

  1. Registry-Based Prospective, Active Surveillance of Medical-Device Safety.

    PubMed

    Resnic, Frederic S; Majithia, Arjun; Marinac-Dabic, Danica; Robbins, Susan; Ssemaganda, Henry; Hewitt, Kathleen; Ponirakis, Angelo; Loyo-Berrios, Nilsa; Moussa, Issam; Drozda, Joseph; Normand, Sharon-Lise; Matheny, Michael E

    2017-02-09

    Background The process of assuring the safety of medical devices is constrained by reliance on voluntary reporting of adverse events. We evaluated a strategy of prospective, active surveillance of a national clinical registry to monitor the safety of an implantable vascular-closure device that had a suspected association with increased adverse events after percutaneous coronary intervention (PCI). Methods We used an integrated clinical-data surveillance system to conduct a prospective, propensity-matched analysis of the safety of the Mynx vascular-closure device, as compared with alternative approved vascular-closure devices, with data from the CathPCI Registry of the National Cardiovascular Data Registry. The primary outcome was any vascular complication, which was a composite of access-site bleeding, access-site hematoma, retroperitoneal bleeding, or any vascular complication requiring intervention. Secondary safety end points were access-site bleeding requiring treatment and postprocedural blood transfusion. Results We analyzed data from 73,124 patients who had received Mynx devices after PCI procedures with femoral access from January 1, 2011, to September 30, 2013. The Mynx device was associated with a significantly greater risk of any vascular complication than were alternative vascular-closure devices (absolute risk, 1.2% vs. 0.8%; relative risk, 1.59; 95% confidence interval [CI], 1.42 to 1.78; P<0.001); there was also a significantly greater risk of access-site bleeding (absolute risk, 0.4% vs. 0.3%; relative risk, 1.34; 95% CI, 1.10 to 1.62; P=0.001) and transfusion (absolute risk, 1.8% vs. 1.5%; relative risk, 1.23; 95% CI, 1.13 to 1.34; P<0.001). The initial alerts occurred within the first 12 months of monitoring. Relative risks were greater in three prespecified high-risk subgroups: patients with diabetes, those 70 years of age or older, and women. All safety alerts were confirmed in an independent sample of 48,992 patients from April 1, 2014, to

  2. Large area flexible SERS active substrates using engineered nanostructures.

    PubMed

    Chung, Aram J; Huh, Yun Suk; Erickson, David

    2011-07-01

    Surface enhanced Raman scattering (SERS) is an analytical sensing method that provides label-free detection, molecularly specific information, and extremely high sensitivity. The Raman enhancement that makes this method attractive is mainly attributed to the local amplification of the incident electromagnetic field that occurs when a surface plasmon mode is excited at a metallic nanostructure. Here, we present a simple, cost effective method for creating flexible, large area SERS-active substrates using a new technique we call shadow mask assisted evaporation (SMAE). The advantage of large, flexible SERS substrates such as these is they have more area for multiplexing and can be incorporated into irregular surfaces such as clothing. We demonstrate the formation of four different types of nanostructure arrays (pillar, nib, ellipsoidal cylinder, and triangular tip) by controlling the evaporation angle, substrate rotation, and deposition rate of metals onto anodized alumina nanoporous membranes as large as 27 mm. In addition, we present experimental results showing how a hybrid structure comprising of gold nanospheres embedded in a silver nano-pillar structure can be used to obtain a 50× SERS enhancement over the raw nanoparticles themselves.

  3. Active Fault Characterization in the Urban Area of Vienna

    NASA Astrophysics Data System (ADS)

    Decker, Kurt; Grupe, Sabine; Hintersberger, Esther

    2016-04-01

    The identification of active faults that lie beneath a city is of key importance for seismic hazard assessment. Fault mapping and characterization in built-up areas with strong anthropogenic overprint is, however, a challenging task. Our study of Quaternary faults in the city of Vienna starts from the re-assessment of a borehole database of the municipality containing several tens of thousands of shallow boreholes. Data provide tight constraints on the geometry of Quaternary deposits and highlight several locations with fault-delimited Middle to Late Pleistocene terrace sediments of the Danube River. Additional information is obtained from geological descriptions of historical outcrops which partly date back to about 1900. The latter were found to be particularly valuable by providing unprejudiced descriptions of Quaternary faults, sometimes with stunning detail. The along-strike continuations of some of the identified faults are further imaged by industrial 2D/3D seismic acquired outside the city limits. The interpretation and the assessment of faults identified within the city benefit from a very well constrained tectonic model of the active Vienna Basin fault system which derived from data obtained outside the city limits. This data suggests that the urban faults are part of a system of normal faults compensating fault-normal extension at a releasing bend of the sinistral Vienna Basin Transfer Fault. Slip rates estimated for the faults in the city are in the range of several hundredths of millimetres per year and match the slip rates of normal faults that were trenched outside the city. The lengths/areas of individual faults estimated from maps and seismic reach up to almost 700 km² suggesting that all of the identified faults are capable of producing earthquakes with magnitudes M>6, some with magnitudes up to M~6.7.

  4. Children with autistic spectrum disorders and speech-generating devices: communication in different activities at home.

    PubMed

    Thunberg, Gunilla; Ahlsén, Elisabeth; Sandberg, Annika Dahlgren

    2007-06-01

    The communication of four children with autistic spectrum disorder was investigated when they were supplied with a speech-generating device (SGD) in three different activities in their home environment: mealtime, story reading and "sharing experiences of the preschool day". An activity based communication analysis, in which collective and individual background factors for the activities were outlined, was used as a basis for the discussion of linguistic coding data derived from video-recordings made before and during SGD intervention. The coded communicative behaviours were engagement in activity, role in turn-taking, communicative form, function and effectiveness. An increase in communicative effectiveness was more noticeable when the SGDs could be used to fulfil goals and roles within the activity. The instruction to the parents to use the SGDs in their communication with the child had an important influence on the activities.

  5. Effects of portable computing devices on posture, muscle activation levels and efficiency.

    PubMed

    Werth, Abigail; Babski-Reeves, Kari

    2014-11-01

    Very little research exists on ergonomic exposures when using portable computing devices. This study quantified muscle activity (forearm and neck), posture (wrist, forearm and neck), and performance (gross typing speed and error rates) differences across three portable computing devices (laptop, netbook, and slate computer) and two work settings (desk and computer) during data entry tasks. Twelve participants completed test sessions on a single computer using a test-rest-test protocol (30min of work at one work setting, 15min of rest, 30min of work at the other work setting). The slate computer resulted in significantly more non-neutral wrist, elbow and neck postures, particularly when working on the sofa. Performance on the slate computer was four times less than that of the other computers, though lower muscle activity levels were also found. Potential or injury or illness may be elevated when working on smaller, portable computers in non-traditional work settings.

  6. Device for controlling a safety valve disposed below an activation pump in a hydrocarbon production well

    SciTech Connect

    Lefebvre, H. M.; Helderle, P. M.

    1985-05-21

    In a hydrocarbon production well in which the effluent is activated by an activation pump installed in a production pipe, a safety valve is disposed in the production pipe below the pump, the safety valve being operated by lowering of an operating member by a controlling device. The controlling device comprises a piston and cylinder system, and connection means connecting the piston to the operating member during the downward movement of the piston. The cylinder and piston system is provided at the level of the pump, and is advantageously constituted by the production pipe and pump respectively, so that pressurized fluid present at the level of the pump will cause downward movement of the piston.

  7. An active drop counting device using condenser microphone for superheated emulsion detector

    SciTech Connect

    Das, Mala; Marick, C.; Kanjilal, D.; Saha, S.

    2008-11-15

    An active device for superheated emulsion detector is described. A capacitive diaphragm sensor or condenser microphone is used to convert the acoustic pulse of drop nucleation to electrical signal. An active peak detector is included in the circuit to avoid multiple triggering of the counter. The counts are finally recorded by a microprocessor based data acquisition system. Genuine triggers, missed by the sensor, were studied using a simulated clock pulse. The neutron energy spectrum of {sup 252}Cf fission neutron source was measured using the device with R114 as the sensitive liquid and compared with the calculated fission neutron energy spectrum of {sup 252}Cf. Frequency analysis of the detected signals was also carried out.

  8. A portable multi-channel wireless NIRS device for muscle activity real-time monitoring.

    PubMed

    Yao, Pengfei; Guo, Weichao; Sheng, Xinjun; Zhang, Dingguo; Zhu, Xiangyang

    2014-01-01

    Near-infrared spectroscopy (NIRS) is a relative new technology in monitoring muscle oxygenation and hemo-dynamics. This paper presents a portable multi-channel wireless NIRS device for real-time monitoring of muscle activity. The NIRS sensor is designed miniaturized and modularized, to make multi-site monitoring convenient. Wireless communication is applied to data transmission avoiding of cumbersome wires and the whole system is highly integrated. Special care is taken to eliminate motion artifact when designing the NIRS sensor and attaching it to human skin. Besides, the system is designed with high sampling rate so as to monitor rapid oxygenation changes during muscle activities. Dark noise and long-term drift tests have been carried out, and the result indicates the device has a good performance of accuracy and stability. In vivo experiments including arterial occlusion and isometric voluntary forearm muscle contraction were performed, demonstrating the system has the ability to monitor muscle oxygenation parameters effectively even in exercise.

  9. Mapping and Monitoring of Dynamic Seafloor Features with Hydroacoustic Devices in Sandy Coastal Areas (German Bight, North Sea)

    NASA Astrophysics Data System (ADS)

    Papenmeier, S.; Mielck, F.; Hass, H. C.

    2014-12-01

    In order to understand marine ecosystems and to provide basic data for a sustainable management in these vulnerable areas, seafloor mapping has become increasingly important. Since the knowledge regarding the seabed environments and their dynamics are still sparse, new mapping techniques have evolved in the last years and hydroacoustic devices became an important tool for quick and reliable mapping. In 2007 we started a monitoring program in the German Bight (North Sea) using sidescan sonar (Imagenex YellowFin, 330 kHz) in a study site comprising approximately 1,500 km2. In subsequent years, the area was mapped repeatedly with a resolution of ~25 cm. For ground truthing, several hundred sediment samples were taken. The investigations reveal that the area is mainly characterized by fine to coarse sand which is arranged in different seafloor features such as subaquatic dunes or relicts of Pleistocene moraines. While the alignment and position of the moraines was stable throughout the years, the dunes can be highly dynamic. Their migration indicates the amount of sediment transport in these areas. Some seafloor features could be identified as so-called sorted bedforms, which are spatially-grain-size-sorted patterns on the seafloor consisting of small rippled medium sand surrounded by smooth fine sand. These flow-transverse features are morphological linked to ridges and depressions and are further maintained by ebb and flood currents of almost equal strengths. The medium sand is separated from the fine sand by sharp boundaries in all directions which were generated by the bidirectional flow field. The extend and alignment of the sorted bedforms seem to be relatively stable in a time frame of 6 years, however small-scale variabilities up to serveral meters could be detected. We suppose that these processes mainly occur during storm surges while the fine-sand layers are winnowed away and hence the shapes of the bedforms changes.

  10. Persistent hydrocephalus due to postural activation of a ventricular shunt anti-gravity device.

    PubMed

    Craven, Claudia L; Toma, Ahmed K; Watkins, Laurence D

    2017-03-01

    The ever present need to balance over drainage with under drainage in hydrocephalus has required innovations including adjustable valves with antigravity devices. These are activated in the vertical position to prevent siphoning. We describe a group of bedridden patients who presented with unexplained under drainage caused by activation of antigravity shunt components produced by peculiar head/body position. Retrospective single centre case series of hydrocephalus patients, treated with ventriculo-peritoneal (VP) shunt insertion between April 2014 - February 2016. These patients presented with clinical and radiological under drainage syndrome. Medical notes were reviewed for clinical picture and outcome. Radiological studies were reviewed assessing shunt placement and ventricular size. Seven patients presented with clinical and radiological under drainage syndrome. A consistent posturing of long term hyper-flexion of the neck whilst lying supine was observed. All patients had similar shunt construct (adjustable Miethke ProGAV valve and shunt assistant anti-gravity component). In each of those patients a hypothesis was formulated that neck flexion was activating the shunt assistance anti-gravity component in supine position. Five patients underwent shunt revision surgery removing the shunt assistant device from the cranium and adding an anti-gravity component to the shunt system at the chest. One had the shunt assistant completely removed and one patient was managed conservatively with mobilisation. All patients had clinical and radiological improvement. Antigravity shunt components implanted cranially in bedridden hydrocephalus patients will produce underdrainage due to head flexion induced anti-gravity device activation. In these patients, anti-gravity devices should be placed at the chest. Alternatively, special nursing attention should be paid to head-trunk angle.

  11. Using volatile additives to alter the morphology and performance of active layers in thin-film molecular photovoltaic devices incorporating bulk heterojunctions.

    PubMed

    Dang, Minh Trung; Wuest, James D

    2013-12-07

    Thin-film photovoltaic devices composed of polymers or small molecules have an exciting future as sources of renewable energy because they can be made in large sizes on flexible surfaces by inexpensive techniques of fabrication. Significant progress in developing new molecular photovoltaic materials and device architectures has been achieved in the last decade. The identity of molecular components in active layers and their individual optoelectronic properties obviously help determine the properties of devices; in addition, however, the behavior of devices depends critically on the nature of the local organization of the components. Recent studies have shown that the morphology of active layers can be tuned by adjusting various parameters, including the solvent used to cast the layer, thermal annealing, and special processing additives. In this review, we summarize the effect of volatile additives on the nanoscale morphology of molecular blends, and we show how these effects can improve the performance of devices. Although we focus on the behavior of mixtures of the type used in current molecular thin-film photovoltaic devices, the subject of our review will interest researchers in all areas of science and technology requiring materials in which separate phases must form intimate long-lived intermixtures with defined structures.

  12. Using Passive Sampling Devices to Assess Chemistry and Toxicity in Streams from six U.S Metropolitan Areas

    NASA Astrophysics Data System (ADS)

    Steven, G. L.; Cuffney, T.; Tate, C.

    2005-05-01

    The U.S. population is growing by almost 3 million people a year with concomitant increase in urban development. Increased urbanization causes changes to watersheds which may affect aquatic biota by altering the physical and chemical environment. We deployed semi-membrane-permeable-devices (SPMDs) for 30 days to passively sample hydrophobic organic contaminants (HOCs) from 180 streams in six major metropolitan areas in the U.S.: Atlanta, Georgia, Dallas/Fort Worth, Texas, Denver, Colorado, Milwaukee, Wisconsin, Portland, Oregon, and Raleigh/Durham, North Carolina. SPMD extracts were tested with two assays: (1)Fluoroscan which estimates PAH concentration (pyrene index) by exposing samples to UV light and (2)P450RGS which measures induction of CYP1A a liver enzyme involved in detoxification of organic contaminants. There was a strong positive relation between urban intensity and both the pyrene index and CYP1A in streams from all six metropolitan areas indicating higher HOC concentrations and greater potential toxicity at higher urbanization levels. Invertebrate community responses as measured by EPT taxa richness and benthic index of biotic integrity were also significantly and negatively correlated with both the pyrene index and CYP1A. Our results suggest that toxicity may be a factor in degradation of invertebrate communities in urban environments.

  13. Use of a Far-Infrared Active Warming Device in Guinea Pigs (Cavia porcellus).

    PubMed

    Zarndt, Bethany S; Buchta, Jessica N; Garver, Lindsey S; Davidson, Silas A; Rowton, Edgar D; Despain, Kenneth E

    2015-11-01

    Small mammals have difficulty maintaining body temperature under anesthesia. This hypothermia is a potential detriment not only to the health and comfort of the animal but also to the integrity of any treatment given or data gathered during the anesthetic period. Using an external warming device to assist with temperature regulation can mitigate these effects. In this study, we investigated the ability of an advanced warming device that uses far-infrared (FIR) heating and responds to real-time core temperature monitoring to maintain a normothermic core temperature in guinea pigs. Body temperatures were measured during 30 min of ketamine-xylazine general anesthesia with and without application of the heating device. The loss of core body heat from anesthetized guinea pigs under typical (unwarmed) conditions was significant, and this loss was almost completely mitigated by application of the FIR heating pad. The significant difference between the temperatures of the actively warmed guinea pigs as compared with the control group began as early as 14 min after anesthetic administration, leading to a 2.6 °C difference at 30 min. Loss of core body temperature was not correlated with animals' body weight; however, weight influences the efficiency of FIR warming slightly. These study results show that the FIR heating device accurately controls core body temperature in guinea pigs, therefore potentially alleviating the effects of body heat loss on animal physiology.

  14. Isolating plasma from blood using a dielectrophoresis-active hydrophoretic device.

    PubMed

    Yan, Sheng; Zhang, Jun; Alici, Gursel; Du, Haiping; Zhu, Yonggang; Li, Weihua

    2014-08-21

    Plasma is a complex substance that contains proteins and circulating nucleic acids and viruses that can be utilised for clinical diagnostics, albeit a precise analysis depends on the plasma being totally free of cells. We proposed the use of a dielectrophoresis (DEP)-active hydrophoretic method to isolate plasma from blood in a high-throughput manner. This microfluidic device consists of anisotropic microstructures embedded on the top of the channel which generate lateral pressure gradients while interdigitised electrodes lay on the bottom of the channel which can push particles or cells into a higher level using a negative DEP force. Large and small particles or cells (3 μm and 10 μm particles, and red blood cells, white blood cells, and platelets) can be focused at the same time in our DEP-active hydrophoretic device at an appropriate flow rate and applied voltage. Based on this principle, all the blood cells were filtrated from whole blood and then the plasma was extracted with a purity of 94.2% and a yield of 16.5% at a flow rate of 10 μL min(-1). This solved the challenging problem caused by the relatively low throughput of the DEP based device. Our DEP-active hydrophoretic device is a flexible and tunable system that can control the lateral positions of particles by modulating the external voltages without redesigning and fabricating a new channel, and because it is easy to operate, it is easily compatible with other microfluidic platforms that are used for further detection.

  15. Large area scanning probe microscope in ultra-high vacuum demonstrated for electrostatic force measurements on high-voltage devices

    PubMed Central

    Glatzel, Thilo; Schmölzer, Thomas; Schöner, Adolf; Reshanov, Sergey; Bartolf, Holger; Meyer, Ernst

    2015-01-01

    Summary Background: The resolution in electrostatic force microscopy (EFM), a descendant of atomic force microscopy (AFM), has reached nanometre dimensions, necessary to investigate integrated circuits in modern electronic devices. However, the characterization of conducting or semiconducting power devices with EFM methods requires an accurate and reliable technique from the nanometre up to the micrometre scale. For high force sensitivity it is indispensable to operate the microscope under high to ultra-high vacuum (UHV) conditions to suppress viscous damping of the sensor. Furthermore, UHV environment allows for the analysis of clean surfaces under controlled environmental conditions. Because of these requirements we built a large area scanning probe microscope operating under UHV conditions at room temperature allowing to perform various electrical measurements, such as Kelvin probe force microscopy, scanning capacitance force microscopy, scanning spreading resistance microscopy, and also electrostatic force microscopy at higher harmonics. The instrument incorporates beside a standard beam deflection detection system a closed loop scanner with a scan range of 100 μm in lateral and 25 μm in vertical direction as well as an additional fibre optics. This enables the illumination of the tip–sample interface for optically excited measurements such as local surface photo voltage detection. Results: We present Kelvin probe force microscopy (KPFM) measurements before and after sputtering of a copper alloy with chromium grains used as electrical contact surface in ultra-high power switches. In addition, we discuss KPFM measurements on cross sections of cleaved silicon carbide structures: a calibration layer sample and a power rectifier. To demonstrate the benefit of surface photo voltage measurements, we analysed the contact potential difference of a silicon carbide p/n-junction under illumination. PMID:26885461

  16. The Impact of Wearable Device Enabled Health Initiative on Physical Activity and Sleep

    PubMed Central

    Crowley, Olga; Kachnowski, Stan

    2016-01-01

    Objectives The Personal Health Management Study (PHMS) is an assessment of the effect of a voluntary employee-facing health initiative using a commercially-available wearable device implemented among 565 employees of Boehringer Ingelheim Pharmaceuticals, Inc. The results of the initiative on physical activity (measured as steps) and sleep is reported. Methods This was a 12-month, prospective, single-cohort intervention study using a wearable activity-measuring device tracking steps and sleep (entire study period) and a system of health-promoting incentives (first nine months of study period). The findings from the first nine study months are reported. Results The mixed model repeated measures approach was used to analyze the data. There was no significant difference in steps between the first month (7915.6 mean steps per person per day) and the last month (7853.4 mean steps per person per day) of the intervention. However, there was a seasonal decline in steps during the intervention period from fall to winter, followed by an increase in steps from winter to spring. In contrast, sleep tended to increase steadily throughout the study period, and the number of hours slept during the last month (7.52 mean hours per person per day) of the intervention was significantly greater than the number of hours slept during the first month (7.16 mean hours per person per day). Conclusions The impact of the initiative on physical activity and sleep differed over the period of time studied. While physical activity did not change between the first and last month of the intervention, the number of hours slept per night increased significantly. Although seasonal changes and study-device habituation may explain the pattern of change in physical activity, further evaluation is required to clarify the reasons underlying the difference in the impact of the initiative on the dynamics of steps and sleep. PMID:27882272

  17. Real-time and noninvasive monitoring of respiration activity of fertilized ova using semiconductor-based biosensing devices.

    PubMed

    Sakata, Toshiya; Makino, Izumi; Kita, Sayaka

    2011-05-01

    In this report, we propose a novel evaluation method of embryo activity, describing the real-time and noninvasive electrical monitoring of embryo activity, caused by fertilization of the sea urchin, using a biologically-coupled field-effect transistor (bio-FET) comprised of semiconductor-based biosensing devices. The detection principle of bio-FET is based on the potentiometric detection of charge density change at the gate insulator, which includes changes of hydrogen ion concentration corresponding to pH variation. The surface potential at the gate surface of the bio-FET increased after the introduction of sperms into the ova, resulting in fertilization on the gate sensing area. The positive shift of surface potential indicates the increase of positive charges of hydrogen ions generated by dissolved carbon dioxide in artificial sea water based on respiration activity of the embryo. Moreover, the electrical signal of embryo activity is suppressed due to the inhibition of cytokinesis by introduction of cytochalasin B. The platform based on the bio-FET is expected to be a real-time, label-free and noninvasive detection system, not only in fundamental studies of embryo activity but also in the evaluation of embryo quality for in vitro fertilization.

  18. An adaptive Hidden Markov model for activity recognition based on a wearable multi-sensor device.

    PubMed

    Li, Zhen; Wei, Zhiqiang; Yue, Yaofeng; Wang, Hao; Jia, Wenyan; Burke, Lora E; Baranowski, Thomas; Sun, Mingui

    2015-05-01

    Human activity recognition is important in the study of personal health, wellness and lifestyle. In order to acquire human activity information from the personal space, many wearable multi-sensor devices have been developed. In this paper, a novel technique for automatic activity recognition based on multi-sensor data is presented. In order to utilize these data efficiently and overcome the big data problem, an offline adaptive-Hidden Markov Model (HMM) is proposed. A sensor selection scheme is implemented based on an improved Viterbi algorithm. A new method is proposed that incorporates personal experience into the HMM model as a priori information. Experiments are conducted using a personal wearable computer eButton consisting of multiple sensors. Our comparative study with the standard HMM and other alternative methods in processing the eButton data have shown that our method is more robust and efficient, providing a useful tool to evaluate human activity and lifestyle.

  19. A simple process for the fabrication of large-area CVD graphene based devices via selective in situ functionalization and patterning

    NASA Astrophysics Data System (ADS)

    Alexeev, Arseny M.; Barnes, Matthew D.; Karthik Nagareddy, V.; Craciun, Monica F.; Wright, C. David

    2017-03-01

    We report a novel approach for the fabrication of micro- and nano-scale graphene devices via the in situ plasma functionalization and in situ lithographic patterning of large-area graphene directly on CVD catalytic metal (Cu) substrates. This enables us to create graphene-based devices in their entirety prior to any transfer processes, simplifying very significantly the device fabrication process and potentially opening up the route to the use of a wider range of target substrates. We demonstrate the capabilities of our technique via the fabrication of a flexible, transparent, graphene/graphene oxide humidity sensor that outperforms a conventional commercial sensor.

  20. Active 2D and carbon-based materials: physics and devices (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Sorger, Volker J.

    2016-09-01

    In nanophotonics we create material-systems, which are structured at length scales smaller than the wavelength of light. When light propagates inside such effective materials numerous novel physics phenomena emerge including thresholdless lasing, atto-joule per bit efficient modulators, and exciton-polariton effects. However, in order to make use of these opportunities, synergistic device designs have to be applied to include materials, electric and photonic constrains - all at the nanoscale. In this talk, I present our recent progress in exploring 2D and TCO materials for active optoelectronics. I highlight nanoscale device demonstrations including their physical operation principle and performance benchmarks. Details include epsilon-bear-zero tuning of thin-film ITO, Graphene electro-static gating via Pauli-blocking, plasmonic electro-optic modulation, and hetero-integrated III-V and carbon-based plasmon lasers on Silicon photonics.

  1. Novel device to conduct flash-heat treatment in efforts to reduce mother-to-child HIV transmission in low-resource areas.

    PubMed

    Suresh, Aneesha; Harn, Cassandra; Pollack, Erica; Kroon, Max; Poluta, Mladen; Kelso, David; Glucksberg, Matthew

    2012-01-01

    The objective of this design project was to create a device to prevent mother-to-child transmission (MTCT) of HIV through breast milk in preterm infants. Our team created a robust and intuitive device which utilizes Flash Heat Treatment (FHT), an established method to inactivate HIV. The FHT method heats jarred breast milk in boiling water for a short amount of time, enough to denature HIV reverse transcriptase while preserving the nutritional value of breast milk. Thorough observation of users and available resources in Cape Town, South Africa enabled establishment of a design that can be used in urban/peri-urban areas. User research conveyed that low cost and effortless household adaptability were the most important elements of the design. As a result, a modified electric kettle was designed to function as a breast milk pasteurization device. Published data illustrating temperature curves during FHT with corresponding virology tests on the pasteurized milk were used to verify whether the device is likely to function effectively. Experimental results indicate that the device matches the required temperature profile. After virology experimentation is complete, the new device may be incorporated into hospitals as well as households in the Cape Town area, and may be expanded to other low resource periurban/urban areas as well.

  2. A status of the activities of the NASA. Marshall Space Flight Center Combustion Devices Technology Team

    NASA Technical Reports Server (NTRS)

    Tucker, Kevin

    1992-01-01

    The Consortium for Computational Fluid Dynamics (CFD) Applications in Propulsion Technology was established to focus on computational fluid dynamics applications in propulsion. Specific areas of effort include developing the CFD technology required to address rocket propulsion issues, validating the technology, and applying the validated technology to design problems. The Combustion Devices Technology Team was formed to implement the above objectives in the broad area of combustion driven flows. In an effort to bring CFD to bear in the design environment, the team has focused its efforts on the Space Transportation Main Engine nozzle. The main emphasis has been on the film cooling scheme used to cool the nozzle wall. Benchmark problems have been chosen to validate CFD film cooling capabilities. CFD simulations of the subscale nozzle have been made. Also, CFD predictions of the base flow resulting from this type of nozzle have been made. The status of these calculations is presented along with future plans. Information is given in viewgraph form.

  3. Safety of active implantable devices during MRI examinations: a finite element analysis of an implantable pump.

    PubMed

    Büchler, Philippe; Simon, Anne; Burger, Jürgen; Ginggen, Alec; Crivelli, Rocco; Tardy, Yanik; Luechinger, Roger; Olsen, Sigbjørn

    2007-04-01

    The goal of this study was to propose a general numerical analysis methodology to evaluate the magnetic resonance imaging (MRI)-safety of active implants. Numerical models based on the finite element (FE) technique were used to estimate if the normal operation of an active device was altered during MRI imaging. An active implanted pump was chosen to illustrate the method. A set of controlled experiments were proposed and performed to validate the numerical model. The calculated induced voltages in the important electronic components of the device showed dependence with the MRI field strength. For the MRI radiofrequency fields, significant induced voltages of up to 20 V were calculated for a 0.3T field-strength MRI. For the 1.5 and 3.0OT MRIs, the calculated voltages were insignificant. On the other hand, induced voltages up to 11 V were calculated in the critical electronic components for the 3.0T MRI due to the gradient fields. Values obtained in this work reflect to the worst case situation which is virtually impossible to achieve in normal scanning situations. Since the calculated voltages may be removed by appropriate protection circuits, no critical problems affecting the normal operation of the pump were identified. This study showed that the proposed methodology helps the identification of the possible incompatibilities between active implants and MR imaging, and can be used to aid the design of critical electronic systems to ensure MRI-safety.

  4. How Accurately Can Your Wrist Device Recognize Daily Activities and Detect Falls?

    PubMed Central

    Gjoreski, Martin; Gjoreski, Hristijan; Luštrek, Mitja; Gams, Matjaž

    2016-01-01

    Although wearable accelerometers can successfully recognize activities and detect falls, their adoption in real life is low because users do not want to wear additional devices. A possible solution is an accelerometer inside a wrist device/smartwatch. However, wrist placement might perform poorly in terms of accuracy due to frequent random movements of the hand. In this paper we perform a thorough, large-scale evaluation of methods for activity recognition and fall detection on four datasets. On the first two we showed that the left wrist performs better compared to the dominant right one, and also better compared to the elbow and the chest, but worse compared to the ankle, knee and belt. On the third (Opportunity) dataset, our method outperformed the related work, indicating that our feature-preprocessing creates better input data. And finally, on a real-life unlabeled dataset the recognized activities captured the subject’s daily rhythm and activities. Our fall-detection method detected all of the fast falls and minimized the false positives, achieving 85% accuracy on the first dataset. Because the other datasets did not contain fall events, only false positives were evaluated, resulting in 9 for the second, 1 for the third and 15 for the real-life dataset (57 days data). PMID:27258282

  5. How Accurately Can Your Wrist Device Recognize Daily Activities and Detect Falls?

    PubMed

    Gjoreski, Martin; Gjoreski, Hristijan; Luštrek, Mitja; Gams, Matjaž

    2016-06-01

    Although wearable accelerometers can successfully recognize activities and detect falls, their adoption in real life is low because users do not want to wear additional devices. A possible solution is an accelerometer inside a wrist device/smartwatch. However, wrist placement might perform poorly in terms of accuracy due to frequent random movements of the hand. In this paper we perform a thorough, large-scale evaluation of methods for activity recognition and fall detection on four datasets. On the first two we showed that the left wrist performs better compared to the dominant right one, and also better compared to the elbow and the chest, but worse compared to the ankle, knee and belt. On the third (Opportunity) dataset, our method outperformed the related work, indicating that our feature-preprocessing creates better input data. And finally, on a real-life unlabeled dataset the recognized activities captured the subject's daily rhythm and activities. Our fall-detection method detected all of the fast falls and minimized the false positives, achieving 85% accuracy on the first dataset. Because the other datasets did not contain fall events, only false positives were evaluated, resulting in 9 for the second, 1 for the third and 15 for the real-life dataset (57 days data).

  6. NCRP Vision for the Future and Program Area Committee Activities.

    PubMed

    Boice, John D

    2017-02-01

    The National Council on Radiation Protection and Measurements (NCRP) believes that the most critical need for the nation in radiation protection is to train, engage, and retain radiation professionals for the future. Not only is the pipeline shrinking, but for some areas there is no longer a pipe! When the call comes to respond, there may be no one to answer the phone! The NCRP "Where are the Radiation Professionals?" initiative, Council Committee (CC) 2, and this year's annual meeting are to focus our efforts to find solutions and not just reiterate the problems. Our next major initiative is CC 1, where the NCRP is making recommendations for the United States on all things dealing with radiation protection. Our last publication was NCRP Report No. 116, Limitation of Exposure to Ionizing Radiation, in 1993-time for an update. NCRP has seven active Program Area Committees on biology and epidemiology, operational concerns, emergency response and preparedness, medicine, environmental issues and waste management, dosimetry, and communications. A major scientific research initiative is the Million Person Study of Low Dose Radiation Health Effects. It includes workers from the Manhattan Project, nuclear weapons test participants (atomic veterans), industrial radiographers, and early medical workers such as radiologists and technologists. This research will answer the one major gap in radiation risk evaluation: what are the health effects when the exposure occurs gradually over time? Other cutting edge initiatives include a re-evaluation of science behind recommendations for lens of the eye dose limits, recommendations for emergency responders on dosimetry after a major radiological incident, guidance to the National Aeronautics and Space Administration with regard to possible central nervous system effects from galactic cosmic rays (the high energy, high mass particles bounding through space), re-evaluating the population exposure to medical radiation (NCRP Report No

  7. 50 CFR 218.180 - Specified activity and specified geographical area and effective dates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Mission Activities in the Naval Surface Warfare Center Panama City Division § 218.180 Specified activity... operations) W-151 (includes Panama City Operating Area), W-155 (includes Pensacola Operating Area), and...

  8. Prominent activation of the intraparietal and somatosensory areas during angle discrimination by intra-active touch.

    PubMed

    Yang, Jiajia; Han, Hongbin; Chui, Dehua; Shen, Yong; Wu, Jinglong

    2012-12-01

    Intra-active touch (IAT) is a process that involves a body part doing the touching (active touch [AT]) and another body part being touched (passive touch [PT]) simultaneously. The brain representation related to IAT is still unclear. A total of 23 subjects carried out angle discrimination under PT, AT and IAT conditions with functional magnetic resonance imaging. All of the tasks were strictly dependent on cutaneous feedback from the finger(s). As the subjects were able to perceive the angle stimuli from the right (touching) and left (touched) sides during the IAT condition, we expected there would be greater brain activation with the IAT condition than for the AT or PT condition. Therefore, we hypothesized that the region within and/or around the intraparietal sulcus (IPS) and the part of the primary somatosensory cortex (SI) that is associated with high-level tactile spatial processing would be more active during the IAT task than during the AT and PT tasks. Compared with the areas activated by the motor somatosensory control task, the most prominent activation areas evoked by the three-angle discrimination tasks were in the SI and secondary somatosensory cortex areas in the bilateral parietal operculum, IPS, lateral occipital complex, insula and cerebellum. Finally, we directly compared IAT with AT and PT, and the results suggest that the contralateral part of IPS and part of the SI are more active under IAT conditions than under either AT or PT conditions. These results suggest that both hemispheres contribute to angle discrimination during IAT.

  9. 76 FR 55394 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-07

    ... Collection; Comment Request; Medical Devices: Humanitarian Use Devices AGENCY: Food and Drug Administration... of information technology. Medical Devices: Humanitarian Use Devices--21 CFR Part 814 (OMB Control... to grant HUD designation of a medical device; (2) exempt an HUD from the effectiveness...

  10. 33 CFR 334.763 - Naval Support Activity Panama City; Gulf of Mexico; restricted area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... City; Gulf of Mexico; restricted area. 334.763 Section 334.763 Navigation and Navigable Waters CORPS OF....763 Naval Support Activity Panama City; Gulf of Mexico; restricted area. (a) The area. The area is... enforced by the Commanding Officer, Naval Support Activity, Panama City Florida, and such agencies as...

  11. 33 CFR 334.763 - Naval Support Activity Panama City; Gulf of Mexico; restricted area.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Naval Support Activity Panama City; Gulf of Mexico; restricted area. 334.763 Section 334.763 Navigation and Navigable Waters CORPS OF....763 Naval Support Activity Panama City; Gulf of Mexico; restricted area. (a) The area. The area...

  12. 33 CFR 334.763 - Naval Support Activity Panama City; Gulf of Mexico; restricted area.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Naval Support Activity Panama City; Gulf of Mexico; restricted area. 334.763 Section 334.763 Navigation and Navigable Waters CORPS OF....763 Naval Support Activity Panama City; Gulf of Mexico; restricted area. (a) The area. The area...

  13. High speed, intermediate resolution, large area laser beam induced current imaging and laser scribing system for photovoltaic devices and modules.

    PubMed

    Phillips, Adam B; Song, Zhaoning; DeWitt, Jonathan L; Stone, Jon M; Krantz, Patrick W; Royston, John M; Zeller, Ryan M; Mapes, Meghan R; Roland, Paul J; Dorogi, Mark D; Zafar, Syed; Faykosh, Gary T; Ellingson, Randy J; Heben, Michael J

    2016-09-01

    We have developed a laser beam induced current imaging tool for photovoltaic devices and modules that utilizes diode pumped Q-switched lasers. Power densities on the order of one sun (100 mW/cm(2)) can be produced in a ∼40 μm spot size by operating the lasers at low diode current and high repetition rate. Using galvanostatically controlled mirrors in an overhead configuration and high speed data acquisition, large areas can be scanned in short times. As the beam is rastered, focus is maintained on a flat plane with an electronically controlled lens that is positioned in a coordinated fashion with the movements of the mirrors. The system can also be used in a scribing mode by increasing the diode current and decreasing the repetition rate. In either mode, the instrument can accommodate samples ranging in size from laboratory scale (few cm(2)) to full modules (1 m(2)). Customized LabVIEW programs were developed to control the components and acquire, display, and manipulate the data in imaging mode.

  14. High speed, intermediate resolution, large area laser beam induced current imaging and laser scribing system for photovoltaic devices and modules

    NASA Astrophysics Data System (ADS)

    Phillips, Adam B.; Song, Zhaoning; DeWitt, Jonathan L.; Stone, Jon M.; Krantz, Patrick W.; Royston, John M.; Zeller, Ryan M.; Mapes, Meghan R.; Roland, Paul J.; Dorogi, Mark D.; Zafar, Syed; Faykosh, Gary T.; Ellingson, Randy J.; Heben, Michael J.

    2016-09-01

    We have developed a laser beam induced current imaging tool for photovoltaic devices and modules that utilizes diode pumped Q-switched lasers. Power densities on the order of one sun (100 mW/cm2) can be produced in a ˜40 μm spot size by operating the lasers at low diode current and high repetition rate. Using galvanostatically controlled mirrors in an overhead configuration and high speed data acquisition, large areas can be scanned in short times. As the beam is rastered, focus is maintained on a flat plane with an electronically controlled lens that is positioned in a coordinated fashion with the movements of the mirrors. The system can also be used in a scribing mode by increasing the diode current and decreasing the repetition rate. In either mode, the instrument can accommodate samples ranging in size from laboratory scale (few cm2) to full modules (1 m2). Customized LabVIEW programs were developed to control the components and acquire, display, and manipulate the data in imaging mode.

  15. Investigating the Efficacy of a Computerized Prompting Device to Assist Children with Autism Spectrum Disorder with Activities of Daily Living

    ERIC Educational Resources Information Center

    Bimbrahw, Justin; Boger, Jennifer; Mihailidis, Alex

    2012-01-01

    Learning to perform self-care skills can pose a major challenge for children with Autism Spectrum Disorder (ASD) as well as the parents and caregivers who support them. The computerized device described in this paper has been used by children with ASD and their carers to autonomously assist with self-care activities. The device uses computer…

  16. An Educational Device for a Hands-on Activity to Visualize the Effect of Atherosclerosis on Blood Flow

    ERIC Educational Resources Information Center

    de Almeida, J. P. P. G. L.; de Lima, J. L. M. P.

    2013-01-01

    An educational device was created to develop a hands-on activity to illustrate how atherosclerosis can dramatically reduce blood flow in human vessels. The device was conceived, designed, and built at the University of Coimbra, in response to a request from the Exploratorio Infante D. Henrique Science Centre Museum, where it is presently…

  17. An Exploration into How Physical Activity Data-Recording Devices Could Be Used in Computer-Supported Data Investigations

    ERIC Educational Resources Information Center

    Lee, Victor R.; DuMont, Maneksha

    2010-01-01

    There is a great potential opportunity to use portable physical activity monitoring devices as data collection tools for educational purposes. Using one such device, we designed and implemented a weeklong workshop with high school students to test the utility of such technology. During that intervention, students performed data investigations of…

  18. Keep Taking the Tablets? Assessing the Use of Tablet Devices in Learning and Teaching Activities in the Further Education Sector

    ERIC Educational Resources Information Center

    Fabian, Khristin; MacLean, Donald

    2014-01-01

    This article summarises the methodology and outcomes of an interventionist/action research project to assess the benefits, and potential pitfalls, of the use of mobile devices in learning and teaching activities in a Further Education environment. A bank of 15 tablet devices were purchased and prepared for classroom use. Staff members were…

  19. Impact of Using a High Surface Area Solid Phase Micro Extraction Device and Fast Gas Chromatography Heating Rates in the Sampling and Analysis of Trace Level Chemical Warfare Agents and CWA-Like Compounds

    DTIC Science & Technology

    2009-09-21

    MICROEXTRACTION DEVICE AND FAST GAS CHROMATOGRAPHY HEATING RATES IN THE SAMPLING AND ANALYSIS OF TRACE LEVEL CHEMICAL WARFARE AGENTS AND CWA-LIKE...v “IMPACT OF USING A HIGH SURFACE AREA SOLID PHASE MICROEXTRACTION DEVICE AND FAST GAS CHROMATOGRAPHY HEATING RATES IN THE SAMPLING AND...10 CHAPTER 3. APPLICATION OF A HIGH SURFACE AREA SOLID PHASE MICROEXTRACTION AIR SAMPLING DEVICE FOR

  20. Single active-layer structured dual-function devices using hybrid polymer-quantum dots.

    PubMed

    Son, Dong-Ick; Park, Dong-Hee; Ie, Sang-Yub; Choi, Won-Kook; Choi, Ji-Won; Li, Fushan; Kim, Tae-Whan

    2008-10-01

    We demonstrate hybrid polymer-quantum dot dual-function devices with a single active-layer structure consisting of CdSe/ZnS semiconductor quantum dots dispersed with poly N-vinylcarbazole (PVK) and 1,3,5-tirs-(N-phenylbenzimidazol-2-yl) benzene (TPBi) fabricated on an indium-tin-oxide (ITO)/glass substrate by using a simple spin-coating technique. The dual-function devices are composed of light-emitting diodes (LED) on the top side and nonvolatile organic bistable memory devices (OBD) on the bottom side and can show electroluminescence (EL) along with electrical bistability concurrently. Both the functionality of LEDs and OBDs can be successfully achieved by adding an electron transport layer (ETL) TPBi to the OBD to attain an LED in which the lowest unoccupied molecular orbital (LUMO) level of TPBi is positioned at the energy level between the conduction band of CdSe/ZnS and the LiF/Al electrode. Through transmission electron microscopy (TEM) study, it is revealed that CdSe/ZnS QDs distributed on the interface of the hole transport layer (HTL) and ETL significantly take part in the electroluminescence process rather than those existing at the outer surface of the ETL.

  1. 33 CFR 334.763 - Naval Support Activity Panama City; Gulf of Mexico; restricted area.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... City; Gulf of Mexico; restricted area. 334.763 Section 334.763 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.763 Naval Support Activity Panama City; Gulf of Mexico; restricted area. (a) The area. The area...

  2. 33 CFR 334.763 - Naval Support Activity Panama City; Gulf of Mexico; restricted area.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... City; Gulf of Mexico; restricted area. 334.763 Section 334.763 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.763 Naval Support Activity Panama City; Gulf of Mexico; restricted area. (a) The area. The area...

  3. Laser fabrication of electrical feedthroughs in polymer encapsulations for active implantable medical devices.

    PubMed

    Gough, Zara; Chaminade, Cedric; Barclay-Monteith, Philip; Kallinen, Annukka; Lei, Wenwen; Ganesan, Rajesh; Grace, John; McKenzie, David R

    2017-01-31

    Hermetic electrical feedthroughs are essential for safe and functional active implantable biomedical devices and for a wide range of other applications such as batteries, supercapacitors, OLEDs and solar cells. Ceramics and metals have previously been the materials of choice for encapsulations, while polymers have advantages of ease of mass production and end user compatibility. We demonstrate a laser sealing technology that gives hermetic, mechanically strong feedthroughs with low electrical resistance in a polyetheretherketone (PEEK) encapsulation. The conductive pathways are wires and sputtered thin films. The water vapor transmission rate through the fabricated encapsulations is comparable to that of PEEK itself.

  4. Conceiving semi-active control devices for large-size monolithic monuments

    NASA Astrophysics Data System (ADS)

    Casciati, Fabio; El Attar, Adel; Casciati, Sara

    2001-07-01

    CHIME is a research project, funded by the European Union, which investigates the adoption of innovative structural control techniques in view of the seismic rehabilitation of the wide monumental cultural heritage in Mediterranean countries as Egypt, Tunisia and Cyprus. The structural control devices are mainly of the semi-active type. In this particular paper one reports the first results achieved within a case study. It considers an Egyptian large size monolithic monument. Alternative solutions for its seismic rehabilitation are eventually conceived and discussed.

  5. Use of a consumer market activity monitoring and feedback device improves exercise capacity and activity levels in COPD.

    PubMed

    Caulfield, Brian; Kaljo, Indira; Donnelly, Seamas

    2014-01-01

    COPD is associated with a gradual decline in physical activity, which itself contributes to a worsening of the underlying condition. Strategies that improve physical activity levels are critical to halt this cycle. Wearable sensor based activity monitoring and persuasive feedback might offer a potential solution. However it is not clear just how much intervention might be needed in this regard - i.e. whether programmes need to be tailored specifically for the target clinical population or whether more simple activity monitoring and feedback solutions, such as that offered in consumer market devices, might be sufficient. This research was carried out to investigate the impact of 4 weeks of using an off the shelf consumer market activity monitoring and feedback application on measures of physical activity, exercise capacity, and health related quality of life in a population of 10 Stage I and II COPD patients. Results demonstrate a significant and positive effect on exercise capacity (measured using a 6-minute walk test) and activity levels (measured in terms of average number of steps per hour) yet no impact on health related quality of life (St Georges Respiratory Disease Questionnaire).

  6. Assistive devices in activities of daily living used by persons with age-related macular degeneration: a population study of 85-year-olds living at home.

    PubMed

    Dahlin Ivanoff, S; Sonn, U

    2005-03-01

    The purpose of this study was to investigate the overall use of assistive devices among persons with age-related macular degeneration (ARMD) and how it is related to dependence in daily activities. This was a retrospective, descriptive, cross-sectional population study of 85-year-olds. The most common category of assistive devices was bathing devices followed by mobility devices. The overall use of assistive devices was 82%, and around 80% of the device users were independent in activities of daily living. They were multiple device users (57%) and used more mobility devices and personal assistance in mobility. In conclusion, the ARMD group comprises very frequent users of assistive devices and uses assistive devices to remain independent. This implies that health services should provide assistive devices at an early stage in the disablement process to avoid the development of dependence and should consider the likelihood of multiple health problems when assessing the needs of assistive devices among persons with ARMD.

  7. Detection of hormone active chemicals using genetically engineered yeast cells and microfluidic devices with interdigitated array electrodes.

    PubMed

    Ino, Kosuke; Kitagawa, Yusuke; Watanabe, Tsuyoshi; Shiku, Hitoshi; Koide, Masahiro; Itayama, Tomoaki; Yasukawa, Tomoyuki; Matsue, Tomokazu

    2009-10-01

    Endocrine disruptors that act like hormones in the endocrine system might have toxic effects. Therefore, it is important to develop a portable device that can detect hormone active chemicals in samples rapidly and easily. In this study, a microfluidic device was developed for the detection of hormone active chemicals using genetically engineered yeast cells. The yeast cells were used as biosensors since they were genetically engineered to respond to the presence of hormone active chemicals by synthesizing beta-galactosidase (beta-gal). For achieving further sensitivity, we incorporated interdigitated array (IDA) electrodes (width, 1.2 microm; gap, 0.8 microm) with 40 electrode fingers into the analytical chamber of the microfluidic device. The yeast cells precultured with a hormone active chemical, 17beta-estradiol (E2), were trapped from the main channel of the device to the analytical camber by electrophoresis. After trapping in the analytical chamber, we performed electrochemical detection of beta-gal induced in the yeast cells with the IDA electrodes. Actually, electrochemical detection was performed on p-aminophenol that was converted from p-aminophenyl-beta-D-galactopyranoside with beta-gal. The electrochemical signals from the yeast cells precultured with 17beta-estradiol were successfully detected with the device. Furthermore, the inhibitory effects of antagonists such as tamoxifen were also detected electrochemically by using the device. Thus, the present microfluidic device can be used for highly sensitive detection of hormone active chemicals.

  8. Physical Activity Measurement Device Agreement: Pedometer Steps/Minute and Physical Activity Time

    ERIC Educational Resources Information Center

    Scruggs, Philip W.; Mungen, Jonathan D.; Oh, Yoonsin

    2010-01-01

    The purpose of this study was to examine agreement between the Walk4Life DUO pedometer (W4L; Walk4Life, Plainfield, Illinois, USA) and two criterion instruments in the measurement of physical activity. Participants (N = 189, M = 16.74 years, SD = 0.99) in high school physical education concurrently wore the DUO (i.e., comparison instrument) and…

  9. 50 CFR 218.120 - Specified activity and geographical area.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the following mid-frequency active sonar (MFAS) sources, high-frequency active sonar (HFAS) sources...-mounted active sonar)—up to 2,890 hours over the course of 5 years (an average of 578 hours per year); (ii) AN/SQS-56 (hull-mounted active sonar)—up to 260 hours over the course of 5 years (an average of...

  10. 50 CFR 218.120 - Specified activity and geographical area.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the following mid-frequency active sonar (MFAS) sources, high-frequency active sonar (HFAS) sources...-mounted active sonar)—up to 2,890 hours over the course of 5 years (an average of 578 hours per year); (ii) AN/SQS-56 (hull-mounted active sonar)—up to 260 hours over the course of 5 years (an average of...

  11. 50 CFR 218.120 - Specified activity and geographical area.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... paragraph (b) of this section and that occur incidental to the activities described in paragraph (c) of this.... long.; 57°16′ N. lat., 151°00′ W. long.; and 55°30′ N. lat., 142°00′ W. long. (c) The taking of marine... the following mid-frequency active sonar (MFAS) sources, high-frequency active sonar (HFAS)...

  12. 50 CFR 218.120 - Specified activity and geographical area.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... paragraph (b) of this section and that occur incidental to the activities described in paragraph (c) of this.... long.; 57°16′ N. lat., 151°00′ W. long.; and 55°30′ N. lat., 142°00′ W. long. (c) The taking of marine... the following mid-frequency active sonar (MFAS) sources, high-frequency active sonar (HFAS)...

  13. Environmental Print Activities for Teaching Mathematics and Content Areas.

    ERIC Educational Resources Information Center

    Rule, Audrey C., Ed.; McIntyre, Sandra, Ed.; Ranous, Meg, Ed.

    Twenty-three mathematics activities that use environmental print materials are presented, along with two activities that focus on music education, one that highlights history concepts, and five science activities. The environmental print materials are words and images cut from food or other product packaging and mounted on mat board cards.…

  14. A microfluidic device for evaluating the dynamics of the metabolism-dependent antioxidant activity of nutrients.

    PubMed

    Lee, Jungwoo; Choi, Jong-ryul; Ha, Sang Keun; Choi, Inwook; Lee, Seung Hwan; Kim, Donghyun; Choi, Nakwon; Sung, Jong Hwan

    2014-08-21

    Various food components are known for their health-promoting effects. However, their biochemical effects are generally evaluated in vitro, and their actual in vivo effect can vary significantly, depending on their metabolic profiles. To evaluate the effect of the liver metabolism on the antioxidant activity, we have developed a two-compartment microfluidic system that integrates the dynamics of liver metabolism and the subsequent antioxidant activity of food components. In the first compartment of the device, human liver enzyme fractions were immobilized inside a poly(ethylene glycol) diacrylate (PEGDA) hydrogel to mimic the liver metabolism. The radical scavenging activity was evaluated by the change of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) absorbance in the second compartment. Reaction engineering and fluid mechanics principles were used to develop a simplified analytical model and a more complex finite element model, which were used to design the chip and determine the optimal flow conditions. For real-time measurements of the reaction on a chip, we developed a custom-made photospectrometer system with an LED light source. The developed microfluidic system showed a linear and dose-dependent antioxidant activity in response to increasing concentration of flavonoid. We also compared the antioxidant activity of flavonoid after various liver metabolic reactions. This microfluidic system can serve as a novel in vitro platform for predicting the antioxidant activity of various food components in a more physiologically realistic manner, as well as for studying the mechanism of action of such food components.

  15. SCIENCE AND TECHNOLOGY ACTIVITIES FOR CHROMIUM IN THE 100 AREAS

    SciTech Connect

    PETERSEN SW

    2009-07-02

    {sm_bullet} Primary Objective: Protect the Columbia River - Focus is control and treatment of contamination at or near the shoreline, which is influenced by bank storage {sm_bullet} Secondary Objective: Reduce hexavalent chromium to <48 parts per billion (ppb) in aquifer (drinking water standard) - Large plumes with isolated areas of high chromium concentrations (> 40,000 ppb), - Unknown source location(s); probably originating in reactor operation areas

  16. High surface area activated carbon prepared from cassava peel by chemical activation.

    PubMed

    Sudaryanto, Y; Hartono, S B; Irawaty, W; Hindarso, H; Ismadji, S

    2006-03-01

    Cassava is one of the most important commodities in Indonesia, an agricultural country. Cassava is one of the primary foods in our country and usually used for traditional food, cake, etc. Cassava peel is an agricultural waste from the food and starch processing industries. In this study, this solid waste was used as the precursor for activated carbon preparation. The preparation process consisted of potassium hydroxide impregnation at different impregnation ratio followed by carbonization at 450-750 degrees C for 1-3 h. The results revealed that activation time gives no significant effect on the pore structure of activated carbon produced, however, the pore characteristic of carbon changes significantly with impregnation ratio and carbonization temperature. The maximum surface area and pore volume were obtained at impregnation ratio 5:2 and carbonization temperature 750 degrees C.

  17. New cosurface capacitive stimulators for the development of active osseointegrative implantable devices

    NASA Astrophysics Data System (ADS)

    Soares Dos Santos, Marco P.; Marote, Ana; Santos, T.; Torrão, João; Ramos, A.; Simões, José A. O.; da Cruz E Silva, Odete A. B.; Furlani, Edward P.; Vieira, Sandra I.; Ferreira, Jorge A. F.

    2016-07-01

    Non-drug strategies based on biophysical stimulation have been emphasized for the treatment and prevention of musculoskeletal conditions. However, to date, an effective stimulation system for intracorporeal therapies has not been proposed. This is particularly true for active intramedullary implants that aim to optimize osseointegration. The increasing demand for these implants, particularly for hip and knee replacements, has driven the design of innovative stimulation systems that are effective in bone-implant integration. In this paper, a new cosurface-based capacitive system concept is proposed for the design of implantable devices that deliver controllable and personalized electric field stimuli to target tissues. A prototype architecture of this system was constructed for in vitro tests, and its ability to deliver controllable stimuli was numerically analyzed. Successful results were obtained for osteoblastic proliferation and differentiation in the in vitro tests. This work provides, for the first time, a design of a stimulation system that can be embedded in active implantable devices for controllable bone-implant integration and regeneration. The proposed cosurface design holds potential for the implementation of novel and innovative personalized stimulatory therapies based on the delivery of electric fields to bone cells.

  18. Computer-aided design of modular protein devices: Boolean AND gene activation

    NASA Astrophysics Data System (ADS)

    Salis, H.; Kaznessis, Y. N.

    2006-12-01

    Many potentially useful synthetic gene networks require the expression of an engineered gene if and only if two different DNA-binding proteins exist in sufficient concentration. While some natural and engineered systems activate gene expression according to a logical AND-like behavior, they often utilize allosteric or cooperative protein-protein interactions, rendering their components unsuitable for a toolbox of modular parts for use in multiple applications. Here, we develop a quantitative model to demonstrate that a small system of interacting fusion proteins, called a protein device, can activate an engineered gene according to the Boolean AND behavior while using only modular protein domains and DNA sites. The fusion proteins are created from transactivating, DNA-binding, non-DNA binding, and protein-protein interaction domains along with the corresponding peptide ligands. Using a combined kinetic and thermodynamic model, we identify the characteristics of the molecular components and their rates of constitutive production that maximize the fidelity of AND behavior. These AND protein devices facilitate the creation of complex genetic programs and may be used to create gene therapies, biosensors and other biomedical and biotechnological applications that turn on gene expression only when multiple DNA-binding proteins are simultaneously present.

  19. Active implantable medical device EMI assessment for wireless power transfer operating in LF and HF bands

    NASA Astrophysics Data System (ADS)

    Hikage, Takashi; Nojima, Toshio; Fujimoto, Hiroshi

    2016-06-01

    The electromagnetic interference (EMI) imposed on active implantable medical devices by wireless power transfer systems (WPTSs) is discussed based upon results of in vitro experiments. The purpose of this study is to present comprehensive EMI test results gathered from implantable-cardiac pacemakers and implantable cardioverter defibrillators exposed to the electromagnetic field generated by several WPTSs operating in low-frequency (70 kHz-460 kHz) and high-frequency (6.78 MHz) bands. The constructed in vitro experimental test system based upon an Irnich’s flat torso phantom was applied. EMI test experiments are conducted on 14 types of WPTSs including Qi-compliant system and EV-charging WPT system mounted on current production EVs. In addition, a numerical simulation model for active implantable medical device (AIMD) EMI estimation based on the experimental test system is newly proposed. The experimental results demonstrate the risk of WPTSs emitting intermittent signal to affect the correct behavior of AIMDs when operating at very short distances. The proposed numerical simulation model is applicable to obtain basically the EMI characteristics of various types of WPTSs.

  20. Stimulus-active polymer actuators for next-generation microfluidic devices

    NASA Astrophysics Data System (ADS)

    Hilber, Wolfgang

    2016-08-01

    Microfluidic devices have not yet evolved into commercial off-the-shelf products. Although highly integrated microfluidic structures, also known as lab-on-a-chip (LOC) and micrototal-analysis-system (µTAS) devices, have consistently been predicted to revolutionize biomedical assays and chemical synthesis, they have not entered the market as expected. Studies have identified a lack of standardization and integration as the main obstacles to commercial breakthrough. Soft microfluidics, the utilization of a broad spectrum of soft materials (i.e., polymers) for realization of microfluidic components, will make a significant contribution to the proclaimed growth of the LOC market. Recent advances in polymer science developing novel stimulus-active soft-matter materials may further increase the popularity and spreading of soft microfluidics. Stimulus-active polymers and composite materials change shape or exert mechanical force on surrounding fluids in response to electric, magnetic, light, thermal, or water/solvent stimuli. Specifically devised actuators based on these materials may have the potential to facilitate integration significantly and hence increase the operational advantage for the end-user while retaining cost-effectiveness and ease of fabrication. This review gives an overview of available actuation concepts that are based on functional polymers and points out promising concepts and trends that may have the potential to promote the commercial success of microfluidics.

  1. New cosurface capacitive stimulators for the development of active osseointegrative implantable devices

    PubMed Central

    Soares dos Santos, Marco P.; Marote, Ana; Santos, T.; Torrão, João; Ramos, A.; Simões, José A. O.; da Cruz e Silva, Odete A. B.; Furlani, Edward P.; Vieira, Sandra I.; Ferreira, Jorge A. F.

    2016-01-01

    Non-drug strategies based on biophysical stimulation have been emphasized for the treatment and prevention of musculoskeletal conditions. However, to date, an effective stimulation system for intracorporeal therapies has not been proposed. This is particularly true for active intramedullary implants that aim to optimize osseointegration. The increasing demand for these implants, particularly for hip and knee replacements, has driven the design of innovative stimulation systems that are effective in bone-implant integration. In this paper, a new cosurface-based capacitive system concept is proposed for the design of implantable devices that deliver controllable and personalized electric field stimuli to target tissues. A prototype architecture of this system was constructed for in vitro tests, and its ability to deliver controllable stimuli was numerically analyzed. Successful results were obtained for osteoblastic proliferation and differentiation in the in vitro tests. This work provides, for the first time, a design of a stimulation system that can be embedded in active implantable devices for controllable bone-implant integration and regeneration. The proposed cosurface design holds potential for the implementation of novel and innovative personalized stimulatory therapies based on the delivery of electric fields to bone cells. PMID:27456818

  2. Origami-inspired active graphene-based paper for programmable instant self-folding walking devices

    PubMed Central

    Mu, Jiuke; Hou, Chengyi; Wang, Hongzhi; Li, Yaogang; Zhang, Qinghong; Zhu, Meifang

    2015-01-01

    Origami-inspired active graphene-based paper with programmed gradients in vertical and lateral directions is developed to address many of the limitations of polymer active materials including slow response and violent operation methods. Specifically, we used function-designed graphene oxide as nanoscale building blocks to fabricate an all-graphene self-folding paper that has a single-component gradient structure. A functional device composed of this graphene paper can (i) adopt predesigned shapes, (ii) walk, and (iii) turn a corner. These processes can be remote-controlled by gentle light or heating. We believe that this self-folding material holds potential for a wide range of applications such as sensing, artificial muscles, and robotics. PMID:26601135

  3. INVITED PAPER: Application of an active device for helicopter noise reduction in JAXA

    NASA Astrophysics Data System (ADS)

    Saito, Shigeru; Kobiki, Noboru; Tanabe, Yasutada

    2010-02-01

    Important issues in noise problems for current helicopters are described. An active tab (AT) was developed as a new active device for noise/vibration reduction under research cooperation between Japan Aerospace Exploration Agency (JAXA) and Kawada Industries, Inc. The wind tunnel test was conducted in order to investigate the effectiveness of the AT on the aeroacoustic characteristics of a helicopter. From the wind tunnel test, the capability of reducing blade vortex interaction (BVI) noise by an AT was verified. A new control law using instantaneous pressure change on a blade during BVI phenomena was introduced and applied to the wind tunnel testing. This new control law shows reasonable controllability for helicopter noise reduction. Furthermore, in order to analyze noise characteristics, the advanced computational fluid dynamics (CFD) code named JAXA_ov3d was developed in JAXA and extended to include CFD-CSD (computational structure dynamics) coupling by using the beam theory for blade deformation.

  4. Validation of a computed radiography device to monitor the HIV-1 RNase H activity

    NASA Astrophysics Data System (ADS)

    Esposito, F.; Fanti, V.; Marzeddu, R.; Randaccio, P.; Tramontano, E.; Zinzula, L.

    2009-08-01

    A commercially available computed radiography (CR) system for dental radiography was used to produce images from radiolabeled polyacrilamide gel electrophoresis (PAGE) assays. Typically, similar investigations require specific and expensive autoradiography devices. The CR unit was characterized in terms of sensitivity and fading by means of a 90Sr source that well simulates the experimental conditions, and then used for quantitative analyses of the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) polymerase-independent ribonuclease H (RNase H) activity monitored by PAGE analysis. The results showed that the present methodology allows quantifying effectively the RNase H catalyses and that the obtained data are in good agreement with previous reference works. Finally, in order to further validate the present method in terms of relationship between enzyme activity, the rate of products formation and signal intensity, a PAGE analyses of the HIV-1 RNase H inhibition by the known diketo acid derivative RDS1643 was carried out.

  5. Combustion devices technology team - An overview and status of STME-related activities

    NASA Technical Reports Server (NTRS)

    Tucker, P. K.; Croteau-Gillespie, Margie

    1992-01-01

    The Consortium for CFD applications in propulsion technology has been formed at NASA/Marshall Space Flight Center. The combustion devices technology team is one of the three teams that constitute the Consortium. While generally aiming to advance combustion devices technology for rocket propulsion, the team's efforts for the last 1 and 1/2 years have been focused on issues relating to the Space Transportation Main Engine (STME) nozzle. The nozzle design uses hydrogen-rich turbine exhaust to cool the wall in a film/dump scheme. This method of cooling presents challenges and associated risks for the nozzle designers and the engine/vehicle integrators. Within the nozzle itself, a key concern is the ability to effectively and efficiently film cool the wall. From the National Launch System vehicle base standpoint, there are concerns with dumping combustible gases at the nozzle exit and their potential adverse effects on the base thermal environment. The Combustion Team has developed and is implementing plans to use validated CFD tools to aid in risk mitigation for both areas.

  6. Behavioral Economics, Wearable Devices, and Cooperative Games: Results From a Population-Based Intervention to Increase Physical Activity

    PubMed Central

    2016-01-01

    Background Health care literature supports the development of accessible interventions that integrate behavioral economics, wearable devices, principles of evidence-based behavior change, and community support. However, there are limited real-world examples of large scale, population-based, member-driven reward platforms. Subsequently, a paucity of outcome data exists and health economic effects remain largely theoretical. To complicate matters, an emerging area of research is defining the role of Superusers, the small percentage of unusually engaged digital health participants who may influence other members. Objective The objective of this preliminary study is to analyze descriptive data from GOODcoins, a self-guided, free-to-consumer engagement and rewards platform incentivizing walking, running and cycling. Registered members accessed the GOODcoins platform through PCs, tablets or mobile devices, and had the opportunity to sync wearables to track activity. Following registration, members were encouraged to join gamified group challenges and compare their progress with that of others. As members met challenge targets, they were rewarded with GOODcoins, which could be redeemed for planet- or people-friendly products. Methods Outcome data were obtained from the GOODcoins custom SQL database. The reporting period was December 1, 2014 to May 1, 2015. Descriptive self-report data were analyzed using MySQL and MS Excel. Results The study period includes data from 1298 users who were connected to an exercise tracking device. Females consisted of 52.6% (n=683) of the study population, 33.7% (n=438) were between the ages of 20-29, and 24.8% (n=322) were between the ages of 30-39. 77.5% (n=1006) of connected and active members met daily-recommended physical activity guidelines of 30 minutes, with a total daily average activity of 107 minutes (95% CI 90, 124). Of all connected and active users, 96.1% (n=1248) listed walking as their primary activity. For members who

  7. Sensor-actuator coupled device for active tracheal tube using solid polymer electrolyte membrane

    NASA Astrophysics Data System (ADS)

    Ihara, Tadashi; Nakamura, Taro; Mukai, Toshiharu; Asaka, Kinji

    2007-04-01

    A sensor-actuator coupled device was developed using solid polymer electrolyte membrane (SPM) as an active tracheal tube for ventilator. Active tracheal tube is a novel type of tube for ventilator that removes patient's phlegm automatically upon sensing the narrowing of trachea by phlegm. This type of active tube is extremely useful in clinical settings as currently the sole measure to remove phlegm from patient's tube is to do it manually by a nurse every few hours. As SPM works both as a sensor and an actuator, an effective compact device was developed. SPM based sensor-actuator coupled device was fabricated with modified gold plating method. Prepared SPM was fixed as an array on a plastic pipe of diameter 22 mm and was connected to a ventilator circuit and driven by a ventilator with a volume control ventilation (VCV) mode. SPM was connected both to a sensing unit and an actuation unit. Generated voltage developed by the membrane with the setting of the maximum pressure from 5 cmH IIO to 20 cmH IIO was in order of several hundred μV. SPM sensor demonstrated a biphasic response to the ventilator flow. The sensor data showed nearly linearly proportional voltage development to the intra-tracheal pressure. The sensed signal was filtered and digitized with an A/D converting unit on a PC board. A real time operating program was used to detect the sensed signal that indicates the narrowing of trachea. The program then activated a driving signal to control the actuation of the membrane. The signal was sent to a D/A converting unit. The output of the D/A unit was sent to an amplifier and the galvanostat unit which drives the membrane with constant current regardless of the change in the load. It was demonstrated that the sensor-actuator unit detects the narrowing of trachea within several hundreds milli-seconds and responds by actuating the same membrane with the driving voltage of 3-4 V and driving current of several hundred milli-ampere for each membrane. SPM array

  8. INSA Scientific Activities in the Space Astronomy Area

    NASA Astrophysics Data System (ADS)

    Pérez Martínez, Ricardo; Sánchez Portal, Miguel

    Support to astronomy operations is an important and long-lived activity within INSA. Probably the best known (and traditional) INSA activities are those related with real-time spacecraft operations: ground station maintenance and operation (ground station engineers and operators); spacecraft and payload real-time operation (spacecraft and instruments controllers); computing infrastructure maintenance (operators, analysts), and general site services. In this paper, we’ll show a different perspective, probably not so well-known, presenting some INSA recent activities at the European Space Astronomy Centre (ESAC) and NASA Madrid Deep Space Communication Complex (MDSCC) directly related to scientific operations. Basic lines of activity involved include: operations support for science operations; system and software support for real time systems; technical administration and IT support; R&D activities, radioastronomy (at MDSCC and ESAC), and scientific research projects. This paper is structured as follows: first, INSA activities in two ESA cornerstone astrophysics missions, XMM-Newton and Herschel, will be outlined. Then, our activities related to scientific infrastructure services, represented by the Virtual Observatory (VO) framework and the Science Archives development facilities, are briefly shown. Radio astronomy activities will be described afterwards, and, finally, a few research topics in which INSA scientists are involved will also be described.

  9. Characterization of large area ZnS(Ag) detector for gross alpha and beta activity measurements in tap water plants

    SciTech Connect

    Lunardon, M.; Cester, D.; Mistura, G.; Moretto, S.; Stevanato, L.; Viesti, G.; Schotanus, P.; Bodewits, E.

    2015-07-01

    In this work we present the characterization of a large area 200 x 200 mm{sup 2} EJ-444 scintillation detector to be used for monitoring gross alpha and beta activity in tap water plants. Specific tests were performed to determine the best setup to readout the light from the detector side in order to have the possibility to stack many detectors and get a compact device with total active area of the order of 1 m{sup 2}. Alpha/Beta discrimination, efficiency and homogeneity tests were carried out with alpha and beta sources. Background from ambient radioactivity was measured as well. Alpha/beta real-time monitoring in drinking water is a goal of the EU project TAWARA{sub R}TM. (authors)

  10. Temporal leukocyte numbers and granulocyte activation in pulsatile and rotary ventricular assist device patients.

    PubMed

    Woolley, Joshua R; Teuteberg, Jeffrey J; Bermudez, Christian A; Bhama, Jay K; Lockard, Kathleen L; Kormos, Robert L; Wagner, William R

    2014-06-01

    Individual ventricular assist device (VAD) design may affect leukocytes and impact immunity. Few studies have presented leukocyte and infection profiles in VAD patients over the course of the implant period. CD11b (MAC-1) expression on granulocytes is an indicator of activation during inflammation, mediating extravasation and the release of reactive oxygen species in tissue. No reported studies have presented MAC-1 expression on circulating granulocytes in VAD patients. Fifty-six patients implanted at a single center with a HeartMate II (HMII; n = 32), HeartWare (HW; n = 12), or Thoratec pneumatic VAD (PVAD; n = 12) between 1999 and 2011 were followed for 120 days of support. The leukocyte profiles and infectious events of all patients were evaluated; additionally, a subset had MAC-1 expression on circulating granulocytes was measured (HMII n = 9; HW n = 7; PVAD n = 4). All groups exhibited a significant peak in leukocyte numbers at postoperative day (POD) 14 while simultaneously experiencing a significant decrease in hematocrit. HMII patients exhibited a 3.2-fold increase in granulocyte MAC-1 expression at POD 14, and the temporal trend over the implant period differed from that experienced by HW patients. Further, HW patients experienced significantly fewer infection events. Alterations in leukocyte profiles and granulocyte activation experienced by VAD patients appear to be device-specific. Elevations in leukocyte activation may be related to an increased risk for infection, although the specific relationship between these phenomena in this patient group is not known.

  11. Real-Time Control of Biological Motor Activity using Graphene-polymer Hybrid Bioenergy Storage Device

    NASA Astrophysics Data System (ADS)

    Lee, Dong; Byun, Kyung-Eun; Choi, Dong; Kim, Eunji; Kim, Daesan; Seo, David; Yang, Heejun; Seo, Sunae; Hong, Seunghun; Hybrid Nanodevice Lab Team; Samsung Research Park Team

    2013-03-01

    Biological motors have been drawing an attention as a key component for highly efficient nanomechanical systems. For such applications, many researchers have tried to control the activity of motor proteins through various methods such as microfluidics or UV-active compounds. However, these methods have some limitations such as the incapability of controlling local biomotor activity and a slow response rate. Herein, we developed a graphene-polymer hybrid nanostructure-based bioenergy storage device which enables the real-time control of biomotor activity. In this strategy, graphene layers functionalized with amine groups were utilized as a transparent electrode supporting the motility of biomotors. And conducting polymer patterns doped with adenosine triphosphate (ATP) were electrically deposited on the graphene and utilized for the fast release of ATP by electrical stimuli through the graphene. Such controlled release of ATP allowed us to control the motility of actin filaments propelled by myosin biomotors in real time. This strategy should enable integrated nanodevices for the real-time control of biological motors to the nanodevices, which can be a significant stepping stone toward hybrid nanomechanical systems based on motor proteins.

  12. PAH assessment in the main Brazilian offshore oil and gas production area using semi-permeable membrane devices (SPMD) and transplanted bivalves

    NASA Astrophysics Data System (ADS)

    André Lourenço, Rafael; Francisco de Oliveira, Fábio; Haddad Nudi, Adriana; Rebello Wagener, Ângela de Luca; Guadalupe Meniconi, Maria de Fátima; Francioni, Eleine

    2015-06-01

    The Campos Basin is Brazil's main oil and gas production area. In 2013, more than 50 million cubic meters of produced water (PW) was discharged into these offshore waters. Despite the large volumes of PW that are discharged in the Campos Basin each day, the ecological concern of the chemicals in the PW are not completely understood. Polycyclic aromatic hydrocarbons (PAH) are the most important contributors to the ecological hazards that are posed by discharged PW. This study aimed to evaluate the potential bioaccumulation of PAH using transplanted bivalves (Nodipecten nodosus) and semi-permeable membrane devices (SPMD). The study was conducted in two platforms that discharge PW (P19 and P40). Another platform that does not discharge PW (P25) was investigated for comparison with the obtained results. Time-integrated hydrocarbon concentrations using SPMD and transplanted bivalves were estimated from the seawater near the three platforms. The bioaccumulation of the PAH in the transplanted bivalves at platforms P19 and P40 were up to fivefold greater than the bioaccumulation of the PAH at platform P25. The lowest PAH concentrations were estimated for platform P25 (4.3-6.2 ng L-1), and the highest PAH concentrations were estimated for platform P19 (9.2-37.3 ng L-1). Both techniques were effective for determining the bioavailability of the PAH and for providing time-integrated hydrocarbon concentrations regarding oil and gas production activities.

  13. System and method of active vibration control for an electro-mechanically cooled device

    DOEpatents

    Lavietes, Anthony D.; Mauger, Joseph; Anderson, Eric H.

    2000-01-01

    A system and method of active vibration control of an electro-mechanically cooled device is disclosed. A cryogenic cooling system is located within an environment. The cooling system is characterized by a vibration transfer function, which requires vibration transfer function coefficients. A vibration controller generates the vibration transfer function coefficients in response to various triggering events. The environments may differ by mounting apparatus, by proximity to vibration generating devices, or by temperature. The triggering event may be powering on the cooling system, reaching an operating temperature, or a reset action. A counterbalance responds to a drive signal generated by the vibration controller, based on the vibration signal and the vibration transfer function, which adjusts vibrations. The method first places a cryogenic cooling system within a first environment and then generates a first set of vibration transfer function coefficients, for a vibration transfer function of the cooling system. Next, the cryogenic cooling system is placed within a second environment and a second set of vibration transfer function coefficients are generated. Then, a counterbalance is driven, based on the vibration transfer function, to reduce vibrations received by a vibration sensitive element.

  14. Electro-active device using radial electric field piezo-diaphragm for sonic applications

    NASA Technical Reports Server (NTRS)

    Bryant, Robert G. (Inventor); Fox, Robert L. (Inventor)

    2005-01-01

    An electro-active transducer for sonic applications includes a ferroelectric material sandwiched by first and second electrode patterns to form a piezo-diaphragm coupled to a mounting frame. When the device is used as a sonic actuator, the first and second electrode patterns are configured to introduce an electric field into the ferroelectric material when voltage is applied to the electrode patterns. When the device is used as a sonic sensor, the first and second electrode patterns are configured to introduce an electric field into the ferroelectric material when the ferroelectric material experiences deflection in a direction substantially perpendicular thereto. In each case, the electrode patterns are designed to cause the electric field to: i) originate at a region of the ferroelectric material between the first and second electrode patterns, and ii) extend radially outward from the region of the ferroelectric material (at which the electric field originates) and substantially parallel to the plane of the ferroelectric material. The mounting frame perimetrically surrounds the peizo-diaphragm and enables attachment of the piezo-diaphragm to a housing.

  15. Active photonic devices based on colloidal semiconductor nanocrystals and organometallic halide perovskites

    NASA Astrophysics Data System (ADS)

    Suárez Alvarez, Isaac

    2016-10-01

    Semiconductor nanocrystals have arisen as outstanding materials to develop a new generation of optoelectronic devices. Their fabrication under simple and low cost colloidal chemistry methods results in cheap nanostructures able to provide a wide range of optical functionalities. Their attractive optical properties include a high absorption cross section below the band gap, a high quantum yield emission at room temperature, or the capability of tuning the band-gap with the size or the base material. In addition, their solution process nature enables an easy integration on several substrates and photonic structures. As a consequence, these nanoparticles have been extensively proposed to develop several photonic applications, such as detection of light, optical gain, generation of light or sensing. This manuscript reviews the great effort undertaken by the scientific community to construct active photonic devices based on these nanoparticles. The conditions to demonstrate stimulated emission are carefully studied by comparing the dependence of the optical properties of the nanocrystals with their size, shape and composition. In addition, this paper describes the design of different photonic architectures (waveguides and cavities) to enhance the generation of photoluminescence, and hence to reduce the threshold of optical gain. Finally, semiconductor nanocrystals are compared to organometallic halide perovskites, as this novel material has emerged as an alternative to colloidal nanoparticles.

  16. Modelling and experimental validation of Textile Pockets based active inflatable device.

    PubMed

    Mehmood, A; Basset, M; Orjuela, R; Dupuis, R; Drean, J Y

    2014-11-01

    This paper aims with the mathematical modelling of an active inflatable device. This device is composed of a compressor, an Electro-pneumatic Pressure Converter (EPC) and an Inflatable Textile fabric Pocket (ITP). The later has interesting mechanical properties and is fabricated using Jacquard knitting technique which allows automatic production of unlimited varieties of pattern weaving without any mould. Thanks to these features, these ITPs have provided a better alternative to the classical airbags made by stretchable polymer material. The proposed mathematical model is obtained by combining sub-models of two main parts of the whole system. In this way, a generalised and flexible model is obtained which can easily take into consideration the ITPs of different shapes. The pressure dynamics inside the ITP are considered by taking into account the air flow rate, variation of the volume of ITP and the length of pneumatic lines joining ITP with compressed air source. The parameters of the whole mathematical model are obtained via identification techniques. The effectiveness of the model is assessed through several experimental tests with the help of a servo hydraulic fatigue testing machine.

  17. PROGRESS ON INSERTION DEVICE RELATED ACTIVITIES AT THE NSLS-II AND ITS FUTURE PLANS

    SciTech Connect

    Tanabe, T.; Chubar, O.; Corwin, T.; Harder, D. A.; He, P.; Rank, J.; Rakowsky, G.; Spataro, C.

    2010-05-23

    National Synchrotron Light Source-II (NSLS-II) project is now in the construction stage. A new insertion device (ID) magnetic measurement facility (MMF) is being set up at Brookhaven National Laboratory in order to satisfy the stringent requirement on the magnetic field measurement of IDs. ISO-Class7 temperature stabilized clean room is being constructed for this purpose. A state-of-the-art Hall probe bench and integrated field measurement system will be installed therein. IDs in the project baseline scope include six damping wigglers, two elliptically polarizing undulators (EPUs), three 3.0m long in-vacuum undulators (IVUs) and one 1.5m long IVU. Three-pole wigglers with peak field over 1 Tesla will be utilized to accommodate the users of bending magnet radiation at the NSLS. Future plans includes: (1) an in-vacuum magnetic measurement system, (2) use of PrFeB magnet for improved cryo undulator, (3) development of advanced optimization program for sorting and shimming of IDs, (4) development of a closed loop He gas refrigerator, (5) switchable quasi-periodic EPU. Design features of the baseline devices, IDMMF and the future plans for NSLS-II ID activities are described.

  18. Three-dimensional kinematic analysis of active cervical spine motion by using a multifaceted marker device.

    PubMed

    Tsunezuka, Hiroaki; Kato, Daishiro; Okada, Satru; Ishihara, Shunta; Shimada, Junichi

    2013-01-01

    Assessing cervical range of motion (CROM) is an important part of the clinical evaluation of patients with conditions such as whiplash syndrome. This study aimed to develop a convenient and accurate system involving multifaceted marker device (MMD)-based assessment of 3-dimensional (3D) dynamic coupled CROM and joint angular velocity. We used an infrared optical tracking system and our newly developed MMD that solved problems such as marker shielding and reflection angle associated with the optical tracking devices and enabled sequential and accurate analysis of the 3D dynamic movement of the polyaxial joint and other structurally complicated joints. The study included 30 asymptomatic young male volunteers (age, 22-27 years). The MMD consisted of 5 surfaces and 5 markers and was attached to the participant's forehead. We measured active CROM (axial rotation, flexion/extension, and lateral bending) and joint angular velocity by the MMD. The MMD was easy to use, safe for patients and operators, could be constructed economically, and generated accurate data such as dynamic coupled CROM and angular velocity.

  19. Preparation of high surface area activated carbon from coconut shells using microwave heating.

    PubMed

    Yang, Kunbin; Peng, Jinhui; Srinivasakannan, C; Zhang, Libo; Xia, Hongying; Duan, Xinhui

    2010-08-01

    The present study attempts to utilize coconut shell to prepare activated carbon using agents such as steam, CO(2) and a mixture of steam-CO(2) with microwave heating. Experimental results show that the BET surface area of activated carbons irrespective of the activation agent resulted in surface area in excess of 2000 m(2)/g. The activation time using microwave heating is very much shorter, while the yield of the activated carbon compares well with the conventional heating methods. The activated carbon prepared using CO(2) activation has the largest BET surface area, however the activation time is approximately 2.5 times higher than the activation using steam or mixture of steam-CO(2). The chemical structure of activated carbons examined using Fourier transformed infra-red spectra (FTIR) did not show any variation in the surface functional groups of the activated carbon prepared using different activation agents.

  20. Cometary activity, discrete outgassing areas, and dust-jet formation

    NASA Technical Reports Server (NTRS)

    Sekanina, Z.

    1991-01-01

    Conceptual models for various types of features observed in cometary comae (jets, spirals, halos, fans, etc.), their computer simulation, and the hydrodynamic models for jet formation are critically reviewed, and evidence for anisotropic, strongly collimated flows of ejecta emanating from discrete active regions (vents) on the rotating cometary nuclei is presented. Techniques employed to generate synthetic comet images that simulate the features observed are described, and their relevance to the primary objects of coma-morphology studies is discussed. Modeling of temporal variations in the water emission from discrete active regions suggests that production curves asymmetric with respect to perihelion should be commonplace. Critical comparisons with the activity profiles of Enke's comet and with light curves of disappearing comets and comets that undergo outbursts are presented. Recent developments in the understanding of the processes that cause the nongravitational perturbations of cometary motions are reviewed, and the observed discontinuities are identified with the birth of new sources and/or deactivation of old vents.

  1. Left posterior-dorsal area 44 couples with parietal areas to promote speech fluency, while right area 44 activity promotes the stopping of motor responses.

    PubMed

    Neef, Nicole E; Bütfering, Christoph; Anwander, Alfred; Friederici, Angela D; Paulus, Walter; Sommer, Martin

    2016-11-15

    Area 44 is a cytoarchitectonically distinct portion of Broca's region. Parallel and overlapping large-scale networks couple with this region thereby orchestrating heterogeneous language, cognitive, and motor functions. In the context of stuttering, area 44 frequently comes into focus because structural and physiological irregularities affect developmental trajectories, stuttering severity, persistency, and etiology. A remarkable phenomenon accompanying stuttering is the preserved ability to sing. Speaking and singing are connatural behaviours recruiting largely overlapping brain networks including left and right area 44. Analysing which potential subregions of area 44 are malfunctioning in adults who stutter, and what effectively suppresses stuttering during singing, may provide a better understanding of the coordination and reorganization of large-scale brain networks dedicated to speaking and singing in general. We used fMRI to investigate functionally distinct subregions of area 44 during imagery of speaking and imaginary of humming a melody in 15 dextral males who stutter and 17 matched control participants. Our results are fourfold. First, stuttering was specifically linked to a reduced activation of left posterior-dorsal area 44, a subregion that is involved in speech production, including phonological word processing, pitch processing, working memory processes, sequencing, motor planning, pseudoword learning, and action inhibition. Second, functional coupling between left posterior area 44 and left inferior parietal lobule was deficient in stuttering. Third, despite the preserved ability to sing, males who stutter showed bilaterally a reduced activation of area 44 when imagine humming a melody, suggesting that this fluency-enhancing condition seems to bypass posterior-dorsal area 44 to achieve fluency. Fourth, time courses of the posterior subregions in area 44 showed delayed peak activations in the right hemisphere in both groups, possibly signaling the

  2. 78 FR 46347 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... international standards ``ISO 9001: Quality Systems Model for Quality Assurance in Design/Development... device CGMP requirements with QS specifications in the international standard ``ISO 9001: Quality Systems... Collection; Comment Request; Medical Devices Current Good Manufacturing Practice Quality System...

  3. 75 FR 36092 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-24

    ... international standards ``ISO 9001: Quality Systems Model for Quality Assurance in Design/Development... harmonizes device CGMP requirements with QS specifications in the international standard ``ISO 9001: Quality... Collection; Comment Request; Medical Devices: Current Good Manufacturing Practice Quality System...

  4. Changes in cervical muscle activity according to the traction force of an air-inflatable neck traction device

    PubMed Central

    Kang, Jong Ho; Park, Tae-Sung

    2015-01-01

    [Purpose] The purpose of this study was to analyze cervical muscle activity at different traction forces of an air-inflatable neck traction device. [Subjects] Eighteen males participated in this study. [Methods] The subjects put on an air-inflatable neck traction device and the traction forces administered were 40, 80, and 120 mmHg. The electromyography (EMG) signals of the splenius capitis, and upper trapezius were measured to assess the muscle activity. [Results] The muscle activity of the splenius capitis was significantly higher at 80, and 120 mmHg compared to 40 mmHg. The muscle activity of the upper trapezius did not show significant differences among the traction forces. [Conclusion] Our research result showed that the air-inflatable home neck traction device did not meet the condition of muscle relaxation. PMID:26504278

  5. Changes in cervical muscle activity according to the traction force of an air-inflatable neck traction device.

    PubMed

    Kang, Jong Ho; Park, Tae-Sung

    2015-09-01

    [Purpose] The purpose of this study was to analyze cervical muscle activity at different traction forces of an air-inflatable neck traction device. [Subjects] Eighteen males participated in this study. [Methods] The subjects put on an air-inflatable neck traction device and the traction forces administered were 40, 80, and 120 mmHg. The electromyography (EMG) signals of the splenius capitis, and upper trapezius were measured to assess the muscle activity. [Results] The muscle activity of the splenius capitis was significantly higher at 80, and 120 mmHg compared to 40 mmHg. The muscle activity of the upper trapezius did not show significant differences among the traction forces. [Conclusion] Our research result showed that the air-inflatable home neck traction device did not meet the condition of muscle relaxation.

  6. Nanostructure and strain effects in active thin films for novel electronic device applications

    NASA Astrophysics Data System (ADS)

    Yuan, Zheng

    2007-12-01

    There are many potential applications of ferroelectric thin films that take advantage of their unique dielectric and piezoelectric properties, such as tunable microwave devices and thin-film active sensors for structural health monitoring (SHM). However, many technical issues still restrict practical applications of ferroelectric thin films, including high insertion loss, limited figure of merit, soft mode effect, large temperature coefficients, and others. The main theme of this thesis is the advanced technique developments, and the new ferroelectric thin films syntheses and investigations for novel device applications. A novel method of additional doping has been adopted to (Ba,Sr)TiO 3 (BSTO) thin films on MgO. By introducing 2% Mn into the stoichiometric BSTO, Mn:BSTO thin films have shown a greatly enhanced dielectric tunability and a reduced insertion loss at high frequencies (10-30 GHz). A new record of a large tunability of 80% with a high dielectric constant of 3800 and an extra low dielectric loss of 0.001 at 1 MHz at room-temperature was achieved. Meanwhile, the new highly epitaxial ferroelectric (Pb,Sr)TiO3 (PSTO) thin films have been synthesized on (001) MgO substrates. PSTO films demonstrated excellent high frequency dielectric properties with high dielectric constants above 1420 and large dielectric tunabilities above 34% at room-temperature up to 20 GHz. In addition, a smaller temperature coefficient from 80 K to 300 K was observed in PSTO films compared to BSTO films. These results indicate that the Mn:BSTO and PSTO films are both good candidates for developing room-temperature tunable microwave devices. Furthermore, crystalline ferroelectric BaTiO3 (BTO) thin films have been deposited directly on metal substrate Ni through a unique in-situ substrate pre-oxidation treatment. The highly oriented nanopillar structural BTO films were grown on the buffered layers created by the pre-oxidation treatment. No interdiffusion or reaction was observed at the

  7. Areas of Unsolved Problems in Caribbean Active Tectonics

    NASA Astrophysics Data System (ADS)

    Mann, P.

    2015-12-01

    I review some unsolved problems in Caribbean active tectonics. At the regional and plate scale: 1) confirm the existence of intraplate deformation zones of the central Caribbean plate that are within the margin of error of ongoing GPS measurements; 2) carry out field studies to evaluate block models versus models for distributed fault shear on the densely populated islands of Jamaica, Hispaniola, Puerto Rico, and the Virgin Islands; 3) carry out paleoseismological research of key plate boundary faults that may have accumulated large strains but have not been previously studied in detail; 4) determine the age of onset and far-field effects of the Cocos ridge and the Central America forearc sliver; 4) investigate the origin and earthquake-potential of obliquely-sheared rift basins along the northern coast of Venezuela; 5) determine the age of onset and regional active, tectonic effects of the Panama-South America collision including the continued activation of the Maracaibo block; and 6) validate longterm rates on active subduction zones with improving, tomographic maps of subducted slabs. At the individual fault scale: 1) determine the mode of termination of large and active strike -slip faults and application of the STEP model (Septentrional, Polochic, El Pilar, Bocono, Santa Marta-Bucaramanaga); 2) improve the understanding of the earthquake potential on the Enriquillo-Plantain Garden fault zone given "off-fault" events such as the 2010 Haiti earthquake; how widespread is this behavior?; and 3) estimate size of future tsunamis from studies of historic or prehistoric slump scars and mass transport deposits; what potential runups can be predicted from this information?; and 4) devise ways to keep rapidly growing, circum-Caribbean urban populations better informed and safer in the face of inevitable and future, large earthquakes.

  8. Active control of near-field coupling in conductively coupled microelectromechanical system metamaterial devices

    NASA Astrophysics Data System (ADS)

    Pitchappa, Prakash; Manjappa, Manukumara; Ho, Chong Pei; Qian, You; Singh, Ranjan; Singh, Navab; Lee, Chengkuo

    2016-03-01

    We experimentally report a structurally reconfigurable metamaterial for active switching of near-field coupling in conductively coupled, orthogonally twisted split ring resonators (SRRs) operating in the terahertz spectral region. Out-of-plane reconfigurable microcantilevers integrated into the dark SRR geometry are used to provide active frequency tuning of dark SRR resonance. The geometrical parameters of individual SRRs are designed to have identical inductive-capacitive resonant frequency. This allows for the excitation of classical analogue of electromagnetically induced transparency (EIT) due to the strong conductive coupling between the SRRs. When the microcantilevers are curved up, the resonant frequency of dark SRR blue-shifts and the EIT peak is completely modulated while the SRRs are still conductively connected. EIT modulation contrast of ˜50% is experimentally achieved with actively switchable group delay of ˜2.5 ps. Electrical control, miniaturized size, and readily integrable fabrication process of the proposed structurally reconfigurable metamaterial make it an ideal candidate for the realization of various terahertz communication devices such as electrically controllable terahertz delay lines, buffers, and tunable data-rate channels.

  9. Modeling activities on the negative-ion-based Neutral Beam Injectors of the Large Helical Device

    SciTech Connect

    Agostinetti, P.; Antoni, V.; Chitarin, G.; Pilan, N.; Serianni, G.; Veltri, P.; Cavenago, M.; Nakano, H.; Takeiri, Y.; Tsumori, K.

    2011-09-26

    At the National Institute for Fusion Science (NIFS) large-scaled negative ion sources have been widely used for the Neutral Beam Injectors (NBIs) mounted on the Large Helical Device (LHD), which is the world-largest superconducting helical system. These injectors have achieved outstanding performances in terms of beam energy, negative-ion current and optics, and represent a reference for the development of heating and current drive NBIs for ITER.In the framework of the support activities for the ITER NBIs, the PRIMA test facility, which includes a RF-drive ion source with 100 keV accelerator (SPIDER) and a complete 1 MeV Neutral Beam system (MITICA) is under construction at Consorzio RFX in Padova.An experimental validation of the codes has been undertaken in order to prove the accuracy of the simulations and the soundness of the SPIDER and MITICA design. To this purpose, the whole set of codes have been applied to the LHD NBIs in a joint activity between Consorzio RFX and NIFS, with the goal of comparing and benchmarking the codes with the experimental data. A description of these modeling activities and a discussion of the main results obtained are reported in this paper.

  10. Continuous Monitoring of Electrical Activity of Pancreatic β-Cells Using Semiconductor-Based Biosensing Devices

    NASA Astrophysics Data System (ADS)

    Sakata, Toshiya; Sugimoto, Haruyo

    2011-02-01

    The electrical activity of rat pancreatic β-cells caused by introduction of glucose was directly and noninvasively detected using a cell-based field-effect transistor (FET). Rat pancreatic β-cells were adhered to the gate sensing surface of the cell-based FET. The principle of cell-based FETs is based on the detection of charge density changes such as pH variation at the interface between the cell membrane and the gate surface. The gate surface potential of pancreatic β-cell-based FET increased continuously after introduction of glucose at a high concentration of 10 mg/ml. This result indicates that the electrical activity of β-cells was successfully monitored on the basis of pH changes, i.e., increase in the concentration of hydrogen ions, at the cell/gate interface using the pancreatic β-cell-based FET. We assume that the pH variation based on hydrogen ion accumulation at the cell/gate interface was induced by activation of respiration accompanied by insulin secretion process following glucose addition. The platform based on the field-effect devices is suitable for application in a real-time, noninvasive, and label-free detection system for cell functional analyses.

  11. Activity monitoring using a mHealth device and correlations with psychopathology in patients with chronic schizophrenia.

    PubMed

    Shin, Seunghwan; Yeom, Chan-Woo; Shin, Cheolmin; Shin, Jae-Hyun; Jeong, Jae Hoon; Shin, Jung Uk; Lee, Young Ryeol

    2016-12-30

    There are few studies of mobile-Health (mHealth) device application with schizophrenic patients. We aimed to quantitatively assess patient's activity and the relationship between their physical activity and the severity of their psychopathologies. Then we attempted to identify the patients who required intervention and evaluated the feasibility of using the mHealth device. A total of 61 of the 76 available hospitalized patients with chronic schizophrenia who participated in the activity programs were enrolled. They wore a mHealth device for a week to assess their activity (steps/day). The Positive and Negative Syndrome Scale (PANSS) was completed by the subjects. As a result, the positive subscale of the PANSS and the positive and negative factors of the PANSS 5-factor structure showed a predictive value for low levels of physical activity. The group of subjects with a high total PANSS score had a significantly lower level of physical activity than the other groups. In conclusion, physical activity showed a significant association with positive symptoms as well as negative symptoms. The mHealth device showed relatively good feasibility for schizophrenic patients. We should pay more attention to the activity of patients with high PANSS scores.

  12. Application of a high surface area solid-phase microextraction air sampling device: collection and analysis of chemical warfare agent surrogate and degradation compounds.

    PubMed

    Stevens, Michael E; Tipple, Christopher A; Smith, Philip A; Cho, David S; Mustacich, Robert V; Eckenrode, Brian A

    2013-09-17

    This work examines a recently improved, dynamic air sampling technique, high surface area solid-phase microextraction (HSA-SPME), developed for time-critical, high-volume sampling and analysis scenarios. The previously reported HSA-SPME sampling device, which provides 10-fold greater surface area compared to commercially available SPME fibers, allowed for an increased analyte uptake per unit time relative to exhaustive sampling through a standard sorbent tube. This sampling device has been improved with the addition of a type-K thermocouple and a custom heater control circuit for direct heating, providing precise (relative standard deviation ∼1%) temperature control of the desorption process for trapped analytes. Power requirements for the HSA-SPME desorption process were 30-fold lower than those for conventional sorbent-bed-based desorption devices, an important quality for a device that could be used for field analysis. Comparisons of the HSA-SPME device when using fixed sampling times for the chemical warfare agent (CWA) surrogate compound, diisopropyl methylphosphonate (DIMP), demonstrated that the HSA-SPME device yielded a greater chromatographic response (up to 50%) relative to a sorbent-bed method. Another HSA-SPME air sampling approach, in which two devices are joined in tandem, was also evaluated for very rapid, low-level, and representative analysis when using discrete sampling times for the compounds of interest. The results indicated that subparts per billion by volume concentration levels of DIMP were detectable with short sampling times (∼15 s). Finally, the tandem HSA-SPME device was employed for the headspace sampling of a CWA degradation compound, 2-(diisopropylaminoethyl) ethyl sulfide, present on cloth material, which demonstrated the capability to detect trace amounts of a CWA degradation product that is estimated to be less volatile than sarin. The rapid and highly sensitive detection features of this device may be beneficial in decision

  13. Devices and methods to measure H2 and CO2 concentrations in gases released from soils and low temperature fumaroles in volcanic areas

    NASA Astrophysics Data System (ADS)

    di Martino, R. M. R.; Camarda, M.; Gurrieri, S.; Valenza, M.

    2009-04-01

    Hydrogen solubility and diffusion have a great relevance to change the redox state of magmas, usually expressed by oxygen fugacity. This influences many chemical and physical properties, such as oxidation state of multivalent elements, kind and abundance of minerals and gas species. These processes change the phase ratios into the volcanic system and so the magma movement capability toward the earth surface and the eruptive dynamics. In past studies several authors (Carapezza et al., 1980; Sato et al., 1982; Sato and McGee, 1985; Wakita et al., 1980) proposed the application of the fuel cells in order to measure reducing capacity of volcanic gases. Their found some clear correlations between variation peaks and volcanic activity but a few reducing capacity changes showed no correlation with it. In this study we characterize a fuel cell device designed to measure hydrogen concentration in a gas mixture. We present test results obtained in laboratory and in field trip, carried out to verify the major interferences of others reducing gas species, commonly present in volcanic emissions, in the measurement carried out with a hydrogen fuel cell sensor. Tests were performed at controlled temperature ad pressure conditions and at air saturated pressure vapour in the cell cathode. A new device to measure simultaneously hydrogen (H2) and carbon dioxide (CO2) concentrations in soil and in low temperature fumaroles in volcanic areas was proposed. The H2-detector is a hydrogen fuel cell, whereas CO2 is measured using an I.R. spectrometer. To build a continuous monitoring station of volcanic activity both sensors were put in a case together with a data logger. Our device has 0.2 mV ppm-1 sensitivity, accuracy of ± 5 ppm and about 10 ppm resolution whit respect to the hydrogen concentration. These instrumental characteristics were obtained applying a 500 ohm resistor to the external circuit that represents the best compromise between sensitivity, resolution, instrumental

  14. Energy expenditure prediction via a footwear-based physical activity monitor: Accuracy and comparison to other devices

    NASA Astrophysics Data System (ADS)

    Dannecker, Kathryn

    2011-12-01

    Accurately estimating free-living energy expenditure (EE) is important for monitoring or altering energy balance and quantifying levels of physical activity. The use of accelerometers to monitor physical activity and estimate physical activity EE is common in both research and consumer settings. Recent advances in physical activity monitors include the ability to identify specific activities (e.g. stand vs. walk) which has resulted in improved EE estimation accuracy. Recently, a multi-sensor footwear-based physical activity monitor that is capable of achieving 98% activity identification accuracy has been developed. However, no study has compared the EE estimation accuracy for this monitor and compared this accuracy to other similar devices. Purpose . To determine the accuracy of physical activity EE estimation of a footwear-based physical activity monitor that uses an embedded accelerometer and insole pressure sensors and to compare this accuracy against a variety of research and consumer physical activity monitors. Methods. Nineteen adults (10 male, 9 female), mass: 75.14 (17.1) kg, BMI: 25.07(4.6) kg/m2 (mean (SD)), completed a four hour stay in a room calorimeter. Participants wore a footwear-based physical activity monitor, as well as three physical activity monitoring devices used in research: hip-mounted Actical and Actigraph accelerometers and a multi-accelerometer IDEEA device with sensors secured to the limb and chest. In addition, participants wore two consumer devices: Philips DirectLife and Fitbit. Each individual performed a series of randomly assigned and ordered postures/activities including lying, sitting (quietly and using a computer), standing, walking, stepping, cycling, sweeping, as well as a period of self-selected activities. We developed branched (i.e. activity specific) linear regression models to estimate EE from the footwear-based device, and we used the manufacturer's software to estimate EE for all other devices. Results. The shoe

  15. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT. STORMWATER SOURCE AREA TREATMENT DEVICE. THE TERRE HILL CONCRETE PRODUCTS TERRE KLEEN™ 09

    EPA Science Inventory

    Verification testing of the Terre Hill Concrete Products Terre Kleen™ 09 was conducted on a 1.27 acre portion of the City of Harrisburg, Pennsylvania Department of Public Works facility. The Terre Kleen™ devices combines primary and secondary chambers, baffles, a screen, and incl...

  16. Agriculture in an area impacted by past uranium mining activities

    SciTech Connect

    Carvalho, F. P.; Oliveira, J. M.; Neves, O.; Vicente, E. M.; Abreu, M. M.

    2007-07-01

    The shallow aquifer near the old Cunha Baixa uranium mine (Viseu, Portugal) was contaminated by acid mine drainage. Concentration of radionuclides in water from irrigation wells and in the topsoil layer of the agriculture fields nearby display enhanced concentrations of uranium, radium and polonium. Two types of agriculture land in this area were selected, one with enhanced and another with low uranium concentrations, for controlled growth of lettuce and potatoes. Plants were grown in replicate portions of land (two plots) in each soil type and were periodically irrigated with water from wells. In each soil, one plot was irrigated with water containing low concentration of dissolved uranium and the other plot with water containing enhanced concentration of dissolved uranium. At the end of the growth season, plants were harvested and analysed, along with soil and irrigation water samples. Results show the accumulation of radionuclides in edible parts of plants, specially in the field plots with higher radionuclide concentrations in soil. Radionuclides in irrigation water contributed less to the radioactivity accumulated in plants than radionuclides from soils. (authors)

  17. A glasses-type wearable device for monitoring the patterns of food intake and facial activity

    PubMed Central

    Chung, Jungman; Chung, Jungmin; Oh, Wonjun; Yoo, Yongkyu; Lee, Won Gu; Bang, Hyunwoo

    2017-01-01

    Here we present a new method for automatic and objective monitoring of ingestive behaviors in comparison with other facial activities through load cells embedded in a pair of glasses, named GlasSense. Typically, activated by subtle contraction and relaxation of a temporalis muscle, there is a cyclic movement of the temporomandibular joint during mastication. However, such muscular signals are, in general, too weak to sense without amplification or an electromyographic analysis. To detect these oscillatory facial signals without any use of obtrusive device, we incorporated a load cell into each hinge which was used as a lever mechanism on both sides of the glasses. Thus, the signal measured at the load cells can detect the force amplified mechanically by the hinge. We demonstrated a proof-of-concept validation of the amplification by differentiating the force signals between the hinge and the temple. A pattern recognition was applied to extract statistical features and classify featured behavioral patterns, such as natural head movement, chewing, talking, and wink. The overall results showed that the average F1 score of the classification was about 94.0% and the accuracy above 89%. We believe this approach will be helpful for designing a non-intrusive and un-obtrusive eyewear-based ingestive behavior monitoring system. PMID:28134303

  18. Self-Assembled, Redox-Active Graphene Electrodes for High-Performance Energy Storage Devices.

    PubMed

    Liu, Tianyuan; Kavian, Reza; Kim, Inkyu; Lee, Seung Woo

    2014-12-18

    Graphene-based materials have been utilized as a promising approach in designing high-performance electrodes for energy storage devices. In line with this approach, functionalized graphene electrodes have been self-assembled from the dispersion of graphene oxide (GO) in water at a low temperature of 80 °C using tetrahydroxyl-1,4-benzoquinone (THQ) as both the reducing and redox-active functionalization agent. We correlated the electrochemical performance of the electrode with surface oxygen chemistry, confirming the role of THQ for the reduction and redox-active functionalization process. The assembled graphene electrodes have a 3D hierarchical porous structure, which can facilitate electronic and ionic transport to support fast charge storage reactions. Utilizing the surface redox reactions introduced by THQ, the functionalized graphene electrodes exhibit high gravimetric capacities of ∼165 mA h/g in Li cells and ∼120 mA h/g in Na cells with high redox potentials over ∼3 V versus Li or Na, proposing promising positive electrodes for both Li and Na ion batteries.

  19. Propeller-based wireless device for active capsular endoscopy in the gastric district.

    PubMed

    Tortora, Giuseppe; Valdastri, Pietro; Susilo, Ekawahyu; Menciassi, Arianna; Dario, Paolo; Rieber, Fabian; Schurr, Marc Oliver

    2009-01-01

    An innovative approach to active locomotion for capsular endoscopy in the gastric district is reported in this paper. Taking advantage of the ingestion of 500 ml of transparent liquid by the patient, an effective distension of the stomach is safely achieved for a timeframe of approximately 30 minutes. Given such a scenario, an active swallowable capsule able to navigate inside the stomach thanks to a four propeller system has been developed. The capsule is 15 mm in diameter and 30 mm in length, and it is composed of a supporting shell containing a wireless microcontroller, a battery and four motors. The motors enable the rotation of propellers located in the rear side of the device, thus obtaining a reliable locomotion and steering of the capsule in all directions in a liquid. The power consumption has been properly optimized in order to achieve an operative lifetime consistent with the time of the diagnostic inspection of the gastric district, assumed to be no more than 30 minutes. The capsule can be easily remotely controlled by the endoscopist using a joystick together with a purposely developed graphical user interface. The capsule design, prototyping, in vitro, ex vivo and preliminary in vivo tests are described in this work.

  20. Active Clearance of Chest Tubes Reduces Re-Exploration for Bleeding After Ventricular Assist Device Implantation

    PubMed Central

    Davis, Mary E.; Haglund, Nicholas A.; Perrault, Louis; Kushwaha, Sudhir S.; Stulak, John M.; Boyle, Edward M.

    2016-01-01

    Chest tubes are utilized to evacuate shed blood after left ventricular assist device (LVAD) implantation, however, they can become clogged, leading to retained blood. We implemented a protocol for active tube clearance (ATC) of chest tubes to determine if this might reduce interventions for retained blood. A total of 252 patients underwent LVAD implantation. Seventy-seven patients had conventional chest tube drainage (group 1), whereas 175 patients had ATC (group 2). A univariate and multivariate analysis adjusting for the use of conventional sternotomy (CS) and minimally invasive left thoracotomy (MILT) was performed. Univariate analysis revealed a 65% reduction in re-exploration (43–15%, p < 0.001), and an 82% reduction in delayed sternal closure (DSC; 34–6%, p <0.001). In a sub-analysis of CS only, there continued to be statistically significant 53% reduction in re-exploration (45% vs. 21%, p = 0.0011), and a 77% reduction in DSC (35% vs. 8%, p < 0.001) in group 2. Using a logistic regression model adjusting for CS versus MILT, there was a significant reduction in re-exploration (odds ratio [OR] = 0.44 [confidence interval {CI} = 0.23–0.85], p = 0.014) and DSC (OR = 0.20 [CI = 0.08–0.46], p <0.001) in group 2. Actively maintaining chest tube patency after LVAD implantation significantly reduces re-exploration and DSC. PMID:27556153

  1. A glasses-type wearable device for monitoring the patterns of food intake and facial activity

    NASA Astrophysics Data System (ADS)

    Chung, Jungman; Chung, Jungmin; Oh, Wonjun; Yoo, Yongkyu; Lee, Won Gu; Bang, Hyunwoo

    2017-01-01

    Here we present a new method for automatic and objective monitoring of ingestive behaviors in comparison with other facial activities through load cells embedded in a pair of glasses, named GlasSense. Typically, activated by subtle contraction and relaxation of a temporalis muscle, there is a cyclic movement of the temporomandibular joint during mastication. However, such muscular signals are, in general, too weak to sense without amplification or an electromyographic analysis. To detect these oscillatory facial signals without any use of obtrusive device, we incorporated a load cell into each hinge which was used as a lever mechanism on both sides of the glasses. Thus, the signal measured at the load cells can detect the force amplified mechanically by the hinge. We demonstrated a proof-of-concept validation of the amplification by differentiating the force signals between the hinge and the temple. A pattern recognition was applied to extract statistical features and classify featured behavioral patterns, such as natural head movement, chewing, talking, and wink. The overall results showed that the average F1 score of the classification was about 94.0% and the accuracy above 89%. We believe this approach will be helpful for designing a non-intrusive and un-obtrusive eyewear-based ingestive behavior monitoring system.

  2. Using a Partial Sum Method and GPS Tracking Data to Identify Area Restricted Search by Artisanal Fishers at Moored Fish Aggregating Devices in the Commonwealth of Dominica

    PubMed Central

    Alvard, Michael; Carlson, David; McGaffey, Ethan

    2015-01-01

    Foragers must often travel from a central place to exploit aggregations of prey. These patches can be identified behaviorally when a forager shifts from travel to area restricted search, identified by a decrease in speed and an increase in sinuosity of movement. Faster, more directed movement is associated with travel. Differentiating foraging behavior at patches from travel to patches is important for a variety of research questions and has now been made easier by the advent of small, GPS devices that can track forager movement with high resolution. In the summer and fall of 2012, movement data were collected from GPS devices placed on foraging trips originating in the artisanal fishing village of Desa Ikan (pseudonym), on the east coast of the Caribbean island nation of the Commonwealth Dominica. Moored FADs are human-made structures anchored to the ocean floor with fish attraction material on or near the surface designed to effectively create a resource patch. The ultimate goal of the research is to understand how property rights are emerging after the introduction of fish aggregating device (FAD) technology at the site in 1999. This paper reports on research to identify area-restricted search foraging behavior at FAD patches. For 22 foraging trips simultaneous behavioral observations were made to ground-truth the GPS movement data. Using a cumulative sum method, area restricted search was identified as negative deviations from the mean travel speed and the method was able to correctly identify FAD patches in every case. PMID:25647288

  3. Activation of cortical areas in music execution and imagining: a high-resolution EEG study.

    PubMed

    Kristeva, Rumyana; Chakarov, Vihren; Schulte-Mönting, Jürgen; Spreer, Joachim

    2003-11-01

    Neuroimaging studies have shown that execution of a musical sequence on an instrument activates bilateral frontal opercular regions, in addition to bilateral sensorimotor and supplementary motor areas. During imagining activation of the same areas without primary sensorimotor areas was shown. We recorded EEG from 58 scalp positions to investigate the temporal sequence and the time course of activation of these areas while violin players prepared to execute, executed, prepared to imagine, or imagined a musical sequence on a violin. During the preparation for the sequence in three of seven musicians investigated the bilateral frontal opercular regions became active earlier than the motor areas and in one of them simultaneously with the motor areas. In two of the musicians a rather variable pattern of activation was observed. The frontal opercular regions were also strongly involved throughout the period of music execution or imagining. The supplementary motor area was involved in both preparation for the sequence and during execution and imagining of the sequence. The left primary sensorimotor area was involved in the preparation and termination of the musical sequence for both execution and imagining. The right sensorimotor area was strongly involved in the preparation for and during the execution of the sequence. We conclude that the bilateral frontal opercular regions are crucial in both preparation for and during music execution and imagining. They may have "mirror neurone" properties that underlie observation or imagining of one's own performance. The motor areas are differentially activated during the preparation and execution or imagining the sequence.

  4. Sensitive monitoring of photocarrier densities in the active layer of a photovoltaic device with time-resolved terahertz reflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Yamashita, Genki; Matsubara, Eiichi; Nagai, Masaya; Kim, Changsu; Akiyama, Hidefumi; Kanemitsu, Yoshihiko; Ashida, Masaaki

    2017-02-01

    We demonstrate the sensitive measurement of photocarriers in an active layer of a GaAs-based photovoltaic device using time-resolved terahertz reflection spectroscopy. We found that the reflection dip caused by Fabry-Pérot interference is strongly affected by the carrier profile in the active layer of the p-i-n structure. The experimental results show that this method is suitable for quantitative evaluation of carrier dynamics in active layers of solar cells under operating conditions.

  5. 33 CFR 334.761 - Naval Support Activity Panama City; St. Andrews Bay; restricted areas.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... City; St. Andrews Bay; restricted areas. 334.761 Section 334.761 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.761 Naval Support Activity Panama City; St. Andrews Bay; restricted areas. (a) The...

  6. 33 CFR 334.761 - Naval Support Activity Panama City; St. Andrews Bay; restricted areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... City; St. Andrews Bay; restricted areas. 334.761 Section 334.761 Navigation and Navigable Waters CORPS... REGULATIONS § 334.761 Naval Support Activity Panama City; St. Andrews Bay; restricted areas. (a) The areas—(1... in this section shall be enforced by the Commanding Officer, Naval Support Activity, Panama...

  7. Zika Virus Knowledge among Pregnant Women Who Were in Areas with Active Transmission

    PubMed Central

    Whittemore, Kate; Tate, Anna; Illescas, Alex; Saffa, Alhaji; Collins, Austin; Varma, Jay K.

    2017-01-01

    We surveyed women in New York, New York, USA, who were in areas with active Zika virus transmission while pregnant. Of 99 women who were US residents, 30 were unaware of the government travel advisory to areas with active Zika virus transmission while pregnant, and 37 were unaware of their pregnancies during travel. PMID:27855041

  8. Zika Virus Knowledge among Pregnant Women Who Were in Areas with Active Transmission.

    PubMed

    Whittemore, Kate; Tate, Anna; Illescas, Alex; Saffa, Alhaji; Collins, Austin; Varma, Jay K; Vora, Neil M

    2017-01-01

    We surveyed women in New York, New York, USA, who were in areas with active Zika virus transmission while pregnant. Of 99 women who were US residents, 30 were unaware of the government travel advisory to areas with active Zika virus transmission while pregnant, and 37 were unaware of their pregnancies during travel.

  9. 32 CFR Appendix C to Part 552 - Authorized Activities for Fort Lewis Maneuver Area Access

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 3 2014-07-01 2014-07-01 false Authorized Activities for Fort Lewis Maneuver Area Access C Appendix C to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF.... 552, App. C Appendix C to Part 552—Authorized Activities for Fort Lewis Maneuver Area Access...

  10. 32 CFR Appendix C to Part 552 - Authorized Activities for Fort Lewis Maneuver Area Access

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 3 2012-07-01 2009-07-01 true Authorized Activities for Fort Lewis Maneuver Area Access C Appendix C to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF.... 552, App. C Appendix C to Part 552—Authorized Activities for Fort Lewis Maneuver Area Access...

  11. Research activities in nuclear astrophysics and related areas

    NASA Technical Reports Server (NTRS)

    1996-01-01

    NASA/GRO grant NAG 5-2081, at the University of Chicago, has provided support for a broad program of theoretical research in nuclear astrophysics and related areas, with regard to gamma-ray and hard X-ray emission from classical nova explosions. This research emphasized the possible detection of 22Na gamma-ray line emission from nearby novae involving ONeMg white dwarfs, the detailed examination of 26Al production in novae, and the possible detection of the predicted early gamma ray emission from novae that arises from the decay of the short lived, positron emitting isotopes of CNO elements. Studies of nova related problems have consumed an increasing fraction of the Principal Investigator's research efforts over the past decade. Current research addresses problems associated with the standard model for the outbursts of the classical novae: the occurrence of thermonuclear runaways (TNR) in the accreted hydrogen rich envelopes on white dwarfs in close binary systems (see, e.g., the reviews by Truran 1982; and Shara 1989). Research in progress and planned for the next three years has three main objectives: (1) to gain an improved understanding of the early evolution of the light curves of, particularly, the fastest novae; (2) to gain an improved understanding of the relative importance of the various possible mechanisms of envelope hydrogen depletion (e.g. winds, common envelope driven mass loss, and nuclear burning) to the long term evolution of novae in outburst; and (3) to seek to provide a somewhat more definitive statement of the role of classical novae in nucleosynthesis. Our proposed 2-D studies of convection during the early phases of the TNR and our systematic attempt to incorporate an improved treatment of radiation hydrodynamics into the hydrodynamic code utilized in our calculations, are particularly relevant to the first of these objectives. Further 2-D studies of the effects of common envelope evolution are intended to provide more realistic constraints

  12. Effect of a fuel activation device (FAD) on particulate matter and black carbon emissions from a diesel locomotive engine.

    PubMed

    Park, Duckshin; Lee, Taejeong; Lee, Yongil; Jeong, Wonseog; Kwon, Soon-Bark; Kim, Dongsool; Lee, Kiyoung

    2017-01-01

    Emission reduction is one of the most efficient control measures in fuel-powered locomotives. The purpose of this study was to determine the reduction in particulate matter (PM) and black carbon (BC) emissions following the installation of a fuel activation device (FAD). The FAD was developed to enhance fuel combustion by atomizing fuel and to increase the surface area per unit volume of injected fuel. Emission reduction by the FAD was evaluated by installing a FAD in an operating diesel locomotive in Mongolia. The test was conducted on a train operating on a round-trip 238-km route between Ulaanbaatar and Choir stations in Mongolia. The fuel consumption rate was slightly reduced following the FAD installation. The FAD installation decreased PM and BC emissions in the diesel locomotive, especially coarse PM. The PM10 reductions achieved after FAD installation were 58.0, 69.7, and 34.2% for the constant velocity, stopping, and acceleration stages of the train's operation, respectively. The BC reduction rates were 29.5, 52.8, and 27.4% for the constant velocity, stopping, and acceleration stages, respectively.

  13. Ag5IO6: novel antibiofilm activity of a silver compound with application to medical devices.

    PubMed

    Incani, Vanessa; Omar, Amin; Prosperi-Porta, Graeme; Nadworny, Patricia

    2015-06-01

    This work explores the unique antibiofilm activity of pentasilver hexaoxoiodate (Ag(5)IO(6)). To test this activity, wound dressings were impregnated with Ag(5)IO(6) and compared with various commercially available silver-containing dressings, as well as dressings containing chlorhexidine, iodine and polyhexamethylene biguanide (PHMB). The materials were tested against Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans for their ability to prevent micro-organism adherence, eliminate planktonic micro-organisms and disrupt/eliminate mature biofilms generated using the MBEC™ assay within 24 h of microbial exposure. Only the Ag(5)IO(6)-containing dressings were able to prevent adherence and eliminate surrounding planktonic micro-organisms for all species tested for ≥28 days of elution with log reductions >4. Two other silver dressings succeeded against P. aeruginosa only after 28 elution days, whilst the PHMB dressing succeeded after 28 days of elution against C. albicans only. Ag(5)IO(6)-containing dressings were able to generate >4 log reductions against all biofilms tested. The only commercial dressings able to generate >4 log reductions against biofilms were iodine against P. aeruginosa and S. aureus, and PHMB against S. aureus. The Ag(5)IO(6) dressings demonstrated complete kill (>4 log reduction) in a standard 30-min planktonic log reduction assay against all species. These results demonstrate that Ag(5)IO(6) has superior activity to a number of antimicrobials, with broad-spectrum efficacy that includes long-term prevention of microbial adherence, rapid kill of planktonic micro-organisms, and the ability to disrupt and eliminate mature biofilms. Thus, Ag(5)IO(6) may be a valuable antimicrobial agent for use in a number of medical device applications, including wound dressings, various catheters or implants.

  14. Bistable laser device with multiple coupled active vertical-cavity resonators

    DOEpatents

    Fischer, Arthur J.; Choquette, Kent D.; Chow, Weng W.

    2003-08-19

    A new class of bistable coupled-resonator vertical-cavity semiconductor laser devices has been developed. These bistable laser devices can be switched, either electrically or optically, between lasing and non-lasing states. A switching signal with a power of a fraction of a milliwatt can change the laser output of such a device by a factor of a hundred, thereby enabling a range of optical switching and data encoding applications.

  15. A novel method for the activity measurement of large-area beta reference sources.

    PubMed

    Stanga, D; De Felice, P; Keightley, J; Capogni, M; Ioan, M R

    2016-03-01

    A novel method has been developed for the activity measurement of large-area beta reference sources. It makes use of two emission rate measurements and is based on the weak dependence between the source activity and the activity distribution for a given value of transmission coefficient. The method was checked experimentally by measuring the activity of two ((60)Co and (137)Cs) large-area reference sources constructed from anodized aluminum foils. Measurement results were compared with the activity values measured by gamma spectrometry. For each source, they agree within one standard uncertainty and also agree within the same limits with the certified values of the source activity.

  16. Detection of active faults using EMR-Technique and Cerescope at Landau area in central Upper Rhine Graben, SW Germany

    NASA Astrophysics Data System (ADS)

    Hagag, Wael; Obermeyer, Hennes

    2016-01-01

    Two conjugate sets of active faults oriented NNE-SSW and NNW-SSE have been detected at Landau area in SW Germany. These faults follow the old trends of the rift-related structures predominating in the Upper Rhine Graben (URG), which originated during Late Eocene-Miocene time. Linear and horizontal measurements were performed by using the Cerescope device and interpreted, applying the Electromagnetic Radiation (EMR) Technique. Linear EMR-profiles were helpful for mapping active faults, while the main horizontal stress (σH, N to NNE) was easily identified with EMR-horizontal measurements. Reactivation of rift-related structures of the Upper Rhine Graben at Landau area produces a new system of active shallow fractures following old trends, and has been detected through the present study by Cerescope applying the EMR-Technique. The present results imply that the Enhanced Geothermal System (EGS) to the south of Landau has a great impact on reactivation of the pre-existing rift-related faults by mechanical hydro-fracturing occurring within the reservoir rocks underneath the area.

  17. Environmental Assessment for AFRL/RY Research & Development Activities & Area B Laser Test Area, Wright-Patterson AFB, Ohio

    DTIC Science & Technology

    2008-10-01

    habitat for the Indiana bat and blazing star stem borer ; however the proposed research activities do not occur in these areas. Therefore, the proposed...catenatus), clubshell mussel (Pleurobema clava, a mussel), and blazing star stem borer (Papaipema beeriana, a moth). A full discussion of threatened and... stem borer (WPAFB, 2007). The following identified wetlands also exist between the facilities and runway: B1, B2, B3, B4, B6, B10, B13, B14, B15

  18. Decreased Activation of Subcortical Brain Areas in the Motor Fatigue State: An fMRI Study

    PubMed Central

    Hou, Li J.; Song, Zheng; Pan, Zhu J.; Cheng, Jia L.; Yu, Yong; Wang, Jun

    2016-01-01

    One aspect of motor fatigue is the exercise-induced reduction of neural activity to voluntarily drive the muscle or muscle group. Functional magnetic resonance imaging provides access to investigate the neural activation on the whole brain level and studies observed changes of activation intensity after exercise-induced motor fatigue in the sensorimotor cortex. However, in human, little evidence exists to demonstrate the role of subcortical brain regions in motor fatigue, which is contradict to abundant researches in rodent indicating that during simple movement, the activity of the basal ganglia is modulated by the state of motor fatigue. Thus, in present study, we explored the effect of motor fatigue on subcortical areas in human. A series of fMRI data were collected from 11 healthy subjects while they were executing simple motor tasks in two conditions: before and under the motor fatigue state. The results showed that in both conditions, movements evoked activation volumes in the sensorimotor areas, SMA, cerebellum, thalamus, and basal ganglia. Of primary importance are the results that the intensity and size of activation volumes in the subcortical areas (i.e., thalamus and basal ganglia areas) are significantly decreased during the motor fatigue state, implying that motor fatigue disturbs the motor control processing in a way that both sensorimotor areas and subcortical brain areas are less active. Further study is needed to clarify how subcortical areas contribute to the overall decreased activity of CNS during motor fatigue state. PMID:27536264

  19. Field evaluation of an automated RDT reader and data management device for Plasmodium falciparum/Plasmodium vivax malaria in endemic areas of Colombia

    PubMed Central

    2014-01-01

    Background Massive implementation of malaria diagnostics in low-resource countries is regarded as a pivotal strategy in control and elimination efforts. Although malaria rapid diagnostic tests (RDTs) are considered a viable alternative, there are still obstacles to the widespread implementation of this strategy, such as reporting constraints and lack of proper quality assurance of RDT-based programmes at point-of-care (POC). Methods A prospective cohort of patients, seeking routine care for febrile episodes at health centres in malaria-endemic areas of Colombia, was used to assess the diagnostic performance of a device based on smartphone technology (Deki ReaderTM, former codename “GenZero”), that assists users at POC to process RDTs. After informed consent, patients were enrolled into the study and blood samples were collected for thick blood smear (TBS) and RDT. The RDT results were interpreted by both visual inspection and Deki Reader device and concordance between visual and device interpretation was measured. Microscopy corrected by real-time polymerase chain reaction (PCR) and microscopy were “gold standard” tests to assess the diagnostic performance. Results In total, 1,807 patients were enrolled at seven health centres in malaria-endemic areas of Colombia. Thirty-three Plasmodium falciparum and 100 Plasmodium vivax cases were positive by corrected microscopy. Both sensitivity and specificity were 93.9% (95% CI 69.7-95.2) and 98.7% (95% CI 98.5-99.4) for P. falciparum, and 98.0% (95% CI 90.3-98.9) and 97.9% (95% CI 97.1-98.5) for P. vivax. Percentage concordance between visual and device interpretation of RDT was 98.5% and 99.0% for P. vivax and P. falciparum, respectively.The RDT, when compared to TBS, showed high sensitivity and specificity for P. falciparum in both visual and device interpretation, and good overall diagnostic performance for P. vivax. Comparison between PCR as gold standard and visual and device interpretation showed acceptable

  20. Application of a Scanning Thermal Nano-Probe for Thermal Imaging of High Frequency Active devices

    NASA Astrophysics Data System (ADS)

    Joodaki, Mojtaba; Janus, Pawel; Gotszalk, Teodor; Kompa, Günter; Edinger, Klaus; Rangelow, Ivo W.

    2005-09-01

    The first application of a new thermal nano-probe based on the changes of electrical resistivity of a nanometer-sized filament with temperature has been presented for the thermal imaging of microwave power active devices. The integration of the filament the fabrication process of the novel thermal probe with a spatial resolution better than 80 nm and a thermal resolution of the order of 10-3 K have already been presented in reference [J. Microelectron. Eng. \\textbf{57--58} (2001) 737]. To demonstrate the capability of the novel thermal nano-probe the measurements have been successfully performed on a 30 fingers GaAs metal--semiconductor field-effect transistor (GaAs-MESFET) with a maximum power dissipation of 2.5 W. The bias circuit has been designed to suppress the undesired microwave oscillations in the transistor. In this case the power dissipation is equal to the dc power input. The near-field measurements using the nano-probe are compared with infrared measurement and three-dimensional finite element static thermal simulations. The good agreement between simulations and measurements confirms the high capability of the nono-probe for these applications.

  1. Examination into the maximum rotational frequency for an in-plane switched active waveplate device

    NASA Astrophysics Data System (ADS)

    Davidson, A. J.; Elston, S. J.; Raynes, E. P.

    2005-05-01

    An examination of an active waveplate device using a one-dimensional model, giving numerical and analytical results, is presented. The model calculates the director and twist configuration by minimizing the free energy of the system with simple homeotropic boundary conditions. The effect of varying the in-plane electric field in both magnitude and direction is examined, and it is shown that the twist through the cell is constant in time as the field is rotated. As the electric field is rotated, the director field lags behind by an angle which increases as the frequency of the electric field rotation increases. When this angle reaches approximately π/4 the director field no longer follows the electric field in a uniform way. Using mathematical analysis it is shown that the conditions on which the director profile will fail to follow the rotating electric field depend on the frequency of electric field rotation, the magnitude of the electric field, the dielectric anisotropy and the viscosity of the liquid crystal.

  2. Kelvin probe force microscopy for local characterisation of active nanoelectronic devices

    PubMed Central

    Beyer, Hannes; Reissner, Patrick; Mensch, Philipp; Riel, Heike; Gotsmann, Bernd

    2015-01-01

    Summary Frequency modulated Kelvin probe force microscopy (FM-KFM) is the method of choice for high resolution measurements of local surface potentials, yet on coarse topographic structures most researchers revert to amplitude modulated lift-mode techniques for better stability. This approach inevitably translates into lower lateral resolution and pronounced capacitive averaging of the locally measured contact potential difference. Furthermore, local changes in the strength of the electrostatic interaction between tip and surface easily lead to topography crosstalk seen in the surface potential. To take full advantage of the superior resolution of FM-KFM while maintaining robust topography feedback and minimal crosstalk, we introduce a novel FM-KFM controller based on a Kalman filter and direct demodulation of sidebands. We discuss the origin of sidebands in FM-KFM irrespective of the cantilever quality factor and how direct sideband demodulation enables robust amplitude modulated topography feedback. Finally, we demonstrate our single-scan FM-KFM technique on an active nanoelectronic device consisting of a 70 nm diameter InAs nanowire contacted by a pair of 120 nm thick electrodes. PMID:26734511

  3. Antimicrobial Activity from Colistin-Heparin Lamellar-Phase Complexes for the Coating of Biomedical Devices.

    PubMed

    Tangso, Kristian J; C D da Cunha, Paulo Henrique; Spicer, Patrick; Li, Jian; Boyd, Ben J

    2016-11-16

    Infections arising in hospitalized patients, particularly those who have undergone surgery and are reliant on receiving treatment through biomedical devices, continue to be a rising concern. It is well-known that aqueous mixtures of oppositely charged surfactant and polymer molecules can self-assemble to form liquid crystalline structures, primarily via electrostatically driven interactions that have demonstrated great potential as tailored-release nanomaterials. Colistin is a re-emerging antibiotic used against multidrug-resistant Gram-negative bacteria. Its amphiphilic structure allows it to form micellar aggregates in solution. Thus, the aim of this study was to determine whether structured complexes form between colistin and negatively charged biopolymers, such as the highly sulfated anticoagulant, heparin. Cross-polarized light microscopy and synchrotron small-angle X-ray scattering were employed to visualize the appearance of birefringent structures and identify liquid crystalline structures, respectively, formed across the interface between solutions of colistin and heparin. A lamellar phase with a lattice parameter of ∼40 Å was formed upon contact between the oppositely charged solutions of colistin and heparin. In addition, in vitro release studies showed a slow release of colistin from the lamellar-phase gel complexes into the bulk media, and disk diffusion bioassays revealed antimicrobial activity against Pseudomonas aeruginosa. This system provides a novel, cost-effective, and simple approach to reducing the risk of infections by potentially applying the formulation as a coating for biomedical implants or tubing.

  4. Use of a Wearable Activity Device in Rural Older Obese Adults

    PubMed Central

    Batsis, John A.; Naslund, John A.; Gill, Lydia E.; Masutani, Rebecca K.; Agarwal, Nayan; Bartels, Stephen J.

    2016-01-01

    Objective: Assess the feasibility and acceptability of Fitbit for supporting behavioral change in rural, older adults with obesity. Method: Eight adults aged ≥65 with a body mass index (BMI) ≥30kg/m2 were recruited from a rural practice and provided a Fitbit Zip device for 30 days. Participants completed validated questionnaires/interviews. Results: Mean age was 73.4 ± 4.0 years (50% female) with a mean BMI of 34.5 ± 4.5kg/m2. We observed reductions in exercise confidence (sticking to it: 34.5 ± 3.3 to 30.9 ± 4.3, p = .04; making time: 18.9 ± 1.3 to 17.0 ± 2.6, p = .03) but no changes in patient activation (45.4 ± 4.3 vs. 45.0 ± 3.9). All reported high satisfaction, seven (87.5%) found Fitbit easy to use, and five (62.5%) found the feedback useful. The majority (n = 6 [75.0%]) were mostly/very satisfied with the intervention. Consistent themes emerged regarding the benefit of self-monitoring and participant motivation. Common concerns included finding time to exercise and lack of a peer group. Conclusion: Use of Fitbit is feasible/acceptable for use among older rural obese adults but may lead to reduced confidence. PMID:28138502

  5. Use of a Wearable Activity Device in Rural Older Obese Adults: A Pilot Study.

    PubMed

    Batsis, John A; Naslund, John A; Gill, Lydia E; Masutani, Rebecca K; Agarwal, Nayan; Bartels, Stephen J

    2016-01-01

    Objective: Assess the feasibility and acceptability of Fitbit for supporting behavioral change in rural, older adults with obesity. Method: Eight adults aged ≥65 with a body mass index (BMI) ≥30kg/m(2) were recruited from a rural practice and provided a Fitbit Zip device for 30 days. Participants completed validated questionnaires/interviews. Results: Mean age was 73.4 ± 4.0 years (50% female) with a mean BMI of 34.5 ± 4.5kg/m(2). We observed reductions in exercise confidence (sticking to it: 34.5 ± 3.3 to 30.9 ± 4.3, p = .04; making time: 18.9 ± 1.3 to 17.0 ± 2.6, p = .03) but no changes in patient activation (45.4 ± 4.3 vs. 45.0 ± 3.9). All reported high satisfaction, seven (87.5%) found Fitbit easy to use, and five (62.5%) found the feedback useful. The majority (n = 6 [75.0%]) were mostly/very satisfied with the intervention. Consistent themes emerged regarding the benefit of self-monitoring and participant motivation. Common concerns included finding time to exercise and lack of a peer group. Conclusion: Use of Fitbit is feasible/acceptable for use among older rural obese adults but may lead to reduced confidence.

  6. Processing-Induced Electrically Active Defects in Black Silicon Nanowire Devices.

    PubMed

    Carapezzi, Stefania; Castaldini, Antonio; Mancarella, Fulvio; Poggi, Antonella; Cavallini, Anna

    2016-04-27

    Silicon nanowires (Si NWs) are widely investigated nowadays for implementation in advanced energy conversion and storage devices, as well as many other possible applications. Black silicon (BSi)-NWs are dry etched NWs that merge the advantages related to low-dimensionality with the special industrial appeal connected to deep reactive ion etching (RIE). In fact, RIE is a well established technique in microelectronics manufacturing. However, RIE processing could affect the electrical properties of BSi-NWs by introducing deep states into their forbidden gap. This work applies deep level transient spectroscopy (DLTS) to identify electrically active deep levels and the associated defects in dry etched Si NW arrays. Besides, the successful fitting of DLTS spectra of BSi-NWs-based Schottky barrier diodes is an experimental confirmation that the same theoretical framework of dynamic electronic behavior of deep levels applies in bulk as well as in low dimensional structures like NWs, when quantum confinement conditions do not occur. This has been validated for deep levels associated with simple pointlike defects as well as for deep levels associated with defects with richer structures, whose dynamic electronic behavior implies a more complex picture.

  7. Calculation of magnetic field-induced current densities for humans from EAS countertop activation/deactivation devices that use ferromagnetic cores

    NASA Astrophysics Data System (ADS)

    Li, Qingxiang; Gandhi, Om P.

    2005-01-01

    Compliance testing of electronic article surveillance (EAS) devices requires that induced current densities in central nervous system (CNS) tissues, i.e. brain and the spinal cord, be less than the prescribed safety limits. Even though ferromagnetic cores are mostly used for activation/deactivation of embedded magnetic tags, assumed equivalent air-core coils with guessed increased number of ampere turns have always been used to calculate the magnetic fields for the proximal region to which a customer is exposed. We show that at low frequencies up to several kilohertz, duality of electric and magnetic circuits may be exploited such that the shaped high reluctance core is modelled as though it was a higher conductivity electric circuit of the corresponding shape. The proposed procedure is tested by examples of two magnetic cores typical of countertop activation/deactivation devices. The equivalent exposure magnetic fields obtained from the dual electric fields are shown to be in excellent agreement (within ±5%) with those measured for these ferromagnetic EAS devices. The previously proposed impedance method is then used to calculate the induced current densities for a 1.974 × 1.974 × 2.93 mm resolution anatomic model of a human. For the two considered EAS systems using excitation currents of 5000 A turns at 200 Hz, the maximum 1 cm2 area-averaged induced current densities in the CNS tissues are calculated and found to be less than the ICNIRP safety limits.

  8. Activating Students' Interest and Participation in Lectures and Practical Courses Using Their Electronic Devices

    ERIC Educational Resources Information Center

    Wijtmans, Maikel; van Rens, Lisette; van Muijlwijk-Koezen, Jacqueline E.

    2014-01-01

    Interactive teaching with larger groups of students can be a challenge, but the use of mobile electronic devices by students (smartphones, tablets, laptops) can be used to improve classroom interaction. We have examined several types of tasks that can be electronically enacted in classes and practical courses using these devices: multiple choice…

  9. 75 FR 69447 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-12

    ... identification provision (UDI) of the Food and Drug Administration Modernization Act (FDAMA) would go a long way... serious adverse health consequences, (2) the device is intended to be implanted in the human body for more than 1 year (referred to as a ``tracked implant''), or (3) the device is life- sustaining or...

  10. From black box to toolbox: Outlining device functionality, engagement activities, and the pervasive information architecture of mHealth interventions

    PubMed Central

    Danaher, Brian G.; Brendryen, Håvar; Seeley, John R.; Tyler, Milagra S.; Woolley, Tim

    2015-01-01

    mHealth interventions that deliver content via mobile phones represent a burgeoning area of health behavior change. The current paper examines two themes that can inform the underlying design of mHealth interventions: (1) mobile device functionality, which represents the technological toolbox available to intervention developers; and (2) the pervasive information architecture of mHealth interventions, which determines how intervention content can be delivered concurrently using mobile phones, personal computers, and other devices. We posit that developers of mHealth interventions will be better able to achieve the promise of this burgeoning arena by leveraging the toolbox and functionality of mobile devices in order to engage participants and encourage meaningful behavior change within the context of a carefully designed pervasive information architecture. PMID:25750862

  11. Guest concentration, bias current, and temperature-dependent sign inversion of magneto-electroluminescence in thermally activated delayed fluorescence devices

    NASA Astrophysics Data System (ADS)

    Deng, Junquan; Jia, Weiyao; Chen, Yingbing; Liu, Dongyu; Hu, Yeqian; Xiong, Zuhong

    2017-03-01

    Non-emissive triplet excited states in devices that undergo thermally activated delayed fluorescence (TADF) can be up-converted to singlet excited states via reverse intersystem crossing (RISC), which leads to an enhanced electroluminescence efficiency. Exciton-based fluorescence devices always exhibit a positive magneto-electroluminescence (MEL) because intersystem crossing (ISC) can be suppressed effectively by an external magnetic field. Conversely, TADF devices should exhibit a negative MEL because RISC is suppressed by the external magnetic field. Intriguingly, we observed a positive MEL in TADF devices. Moreover, the sign of the MEL was either positive or negative, and depended on experimental conditions, including doping concentration, current density and temperature. The MEL observed from our TADF devices demonstrated that ISC in the host material and RISC in the guest material coexisted. These competing processes were affected by the experimental conditions, which led to the sign change of the MEL. This work gives important insight into the energy transfer processes and the evolution of excited states in TADF devices.

  12. The application of machine learning in multi sensor data fusion for activity recognition in mobile device space

    NASA Astrophysics Data System (ADS)

    Marhoubi, Asmaa H.; Saravi, Sara; Edirisinghe, Eran A.

    2015-05-01

    The present generation of mobile handheld devices comes equipped with a large number of sensors. The key sensors include the Ambient Light Sensor, Proximity Sensor, Gyroscope, Compass and the Accelerometer. Many mobile applications are driven based on the readings obtained from either one or two of these sensors. However the presence of multiple-sensors will enable the determination of more detailed activities that are carried out by the user of a mobile device, thus enabling smarter mobile applications to be developed that responds more appropriately to user behavior and device usage. In the proposed research we use recent advances in machine learning to fuse together the data obtained from all key sensors of a mobile device. We investigate the possible use of single and ensemble classifier based approaches to identify a mobile device's behavior in the space it is present. Feature selection algorithms are used to remove non-discriminant features that often lead to poor classifier performance. As the sensor readings are noisy and include a significant proportion of missing values and outliers, we use machine learning based approaches to clean the raw data obtained from the sensors, before use. Based on selected practical case studies, we demonstrate the ability to accurately recognize device behavior based on multi-sensor data fusion.

  13. Guest concentration, bias current, and temperature-dependent sign inversion of magneto-electroluminescence in thermally activated delayed fluorescence devices

    PubMed Central

    Deng, Junquan; Jia, Weiyao; Chen, Yingbing; Liu, Dongyu; Hu, Yeqian; Xiong, Zuhong

    2017-01-01

    Non-emissive triplet excited states in devices that undergo thermally activated delayed fluorescence (TADF) can be up-converted to singlet excited states via reverse intersystem crossing (RISC), which leads to an enhanced electroluminescence efficiency. Exciton-based fluorescence devices always exhibit a positive magneto-electroluminescence (MEL) because intersystem crossing (ISC) can be suppressed effectively by an external magnetic field. Conversely, TADF devices should exhibit a negative MEL because RISC is suppressed by the external magnetic field. Intriguingly, we observed a positive MEL in TADF devices. Moreover, the sign of the MEL was either positive or negative, and depended on experimental conditions, including doping concentration, current density and temperature. The MEL observed from our TADF devices demonstrated that ISC in the host material and RISC in the guest material coexisted. These competing processes were affected by the experimental conditions, which led to the sign change of the MEL. This work gives important insight into the energy transfer processes and the evolution of excited states in TADF devices. PMID:28295056

  14. Preparation of carboxylated Ag nanoparticles as a coating material for medical devices and control of antibacterial activity.

    PubMed

    Furuzono, Tsutomu; Iwamoto, Takashi; Azuma, Yoshinao; Okada, Masahiro; Sawa, Yoshiki

    2013-12-01

    Carboxyl group-donated silver (Ag) nanoparticles for coating on medical devices were prepared by a two-phase reduction system in situ. AgNO3 was the Ag ion source, tetraoctylammonium bromide [N(C8H17)4Br] the phase-transfer agent, sodium tetrahydroborate (NaBH4) the reducing agent and 10-carboxy-1-decanthiol (C11H22O2S, CDT) the capping agent. The characterizations of the Ag nanoparticles were conducted by diffuse reflectance Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric differential thermal analysis (TG/DTA) and transmission electron microscope. With CDT capped on Ag nanoparticles, we found that the band around 3,100 cm(-1) was attributed to COO-H stretching vibration, two adsorptions at 2,928 and 2,856 cm(-1) to C-H symmetric/anti-symmetric stretching vibration, and at 1,718 cm(-1) to C=O stretching vibration in the FT-IR spectra. The organic components of the carboxylated Ag nanoparticles were 5.8-25.9 wt%, determined by TG/DTA. The particle sizes of the carboxylated Ag nanoparticles were well controlled by the addition of the capping agent, CDT, into the reaction system. The antimicrobial activity of the Ag nanoparticles covered with different contents of CDT against E. coli was evaluated. Smaller-size Ag nanoparticles showed higher antibacterial activity, which depended on a surface area that attached easily to a microorganism cell membrane.

  15. The role of ELM filaments in setting the ELM wetted area in MAST and the implications for future devices

    NASA Astrophysics Data System (ADS)

    Thornton, A. J.; Allan, S. Y.; Dudson, B. D.; Elmore, S. D.; Fishpool, G. M.; Harrison, J. R.; Kirk, A.; The MAST Team; The EUROfusion MST1 Team

    2017-01-01

    The ELM wetted area is a key factor in the peak power load during an ELM, as it sets the region over which the ELM energy is deposited. The deposited heat flux at the target is seen to have striations in the profiles that are generated by the arrival of filaments ejected from the confined plasma. The effect of the filaments arriving at the target on the ELM wetted area, and the relation to the midplane mode number is investigated in this paper using infrared (IR) thermography and high speed visible imaging (>10 kHz). Type I ELMs are analysed, as these have the largest heat fluxes and are observed to have toroidal mode numbers of between 5 and 15. The IR profiles during the ELMs show clear filamentary structures that evolve during the ELM cycle. An increasing number of striations at the target is seen to correspond to an increase in the wetted area. Analysis shows that the ratio of the ELM wetted area to the inter-ELM wetted area, a key parameter for ITER, for the type I ELMs is between 3 and 6 for lower single null plasmas and varies with the ELM midplane mode number, as determined by visible measurements. Monte-Carlo modelling of the ELMs is used to understand the variation seen in the wetted area and the effect of an increased mode number; the modelling replicates the trends seen in the experimental data and supports the observation of increased toroidal mode number generating larger target ELM wetted areas. ITER is thought to be peeling unstable which would imply a lower ELM mode number compared to MAST which is peeling-ballooning unstable. The results of this analysis suggest that the lower n peeling unstable ELMs expected for ITER will have smaller wetted areas than peeling-ballooning unstable ELMs. A smaller wetted area will increase the level of ELM control required, therefore a key prediction required for ITER is the expected ELM mode number.

  16. Acute Effects of a Therapeutic Mobility Device on Physical Activity and Heart Rate in Children with Down Syndrome

    ERIC Educational Resources Information Center

    Hauck, Janet L.; Ulrich, Dale A.

    2015-01-01

    Purpose: The purpose of this feasibility study was to provide an opportunity to increase physical activity (PA) and heart rate (HR) for children with Down syndrome (DS) during unstructured group exercise utilizing a riding device called the Power Pumper®. Method: Twenty-four children aged 5 to 7 years old participated in this case-control study,…

  17. Scapulothoracic Muscle Activity during Use of a Wall Slide Device (WSD), a Comparison with the General Wall Push up Plus

    PubMed Central

    Park, Se-yeon; Ahn, Tae-kyung; Eom, Ji-hwan; Youn, Hyun-ji; Kim, In-kwang; Yoo, Won-gyu

    2014-01-01

    [Purpose] The purpose of this study was to evaluate the effect of the wall slide device on activation of the scapulothoracic musculature. [Subjects] We recruited 15 healthy male subjects. [Methods] The subjects performed the general wall push-up plus (WPUP) and the wall slide with device (WSD) exercises. During the exercises, the muscle activities of the upper and lower trapezius (UT, LT), middle and lower serratus anterior (MSA, LSA), and pectoralis major (PM) were measured. [Results] The normalized muscle activity data of the WSD were significantly higher in UT, MSA and LSA than the WPUP. [Conclusion] Our results suggest that exercise using the WSD can more effectively activate the scapulothoracic musculature than the general WPUP. PMID:25013271

  18. Functional Specificity of the Visual Word Form Area: General Activation for Words and Symbols but Specific Network Activation for Words

    ERIC Educational Resources Information Center

    Reinke, Karen; Fernandes, Myra; Schwindt, Graeme; O'Craven, Kathleen; Grady, Cheryl L.

    2008-01-01

    The functional specificity of the brain region known as the Visual Word Form Area (VWFA) was examined using fMRI. We explored whether this area serves a general role in processing symbolic stimuli, rather than being selective for the processing of words. Brain activity was measured during a visual 1-back task to English words, meaningful symbols…

  19. Distinct activated cortical areas and volumes in Uygur-Chinese bilinguals

    PubMed Central

    Jiang, Mei; Yang, Li-Xia; Jia, Lin; Shi, Xin; Wang, Hong; Wang, Lin-yun; Abaydulla, Yari; Zhu, Li-Na; Jia, Wen-Xiao

    2015-01-01

    Objective The aim of this study is to evaluate variations in cortical activation in early and late Uygur-Chinese bilinguals from the Xinjiang Uygur Autonomous Region of China. Methodology: During a semantic judgment task with visual stimulation by a single Chinese or Uygur word, functional magnetic resonance imaging (fMRI) was performed. The fMRI data regarding activated cortical areas and volumes by both languages were analyzed. Results The first language (L1) and second language (L2) activated language-related hemispheric regions, including the left inferior frontal and parietal cortices, and L1 specifically activated the left middle temporal gyrus. For both L1 and L2, cortical activation was greater in the left hemisphere, and there was no significant difference in the lateralization index (LI) between the two languages (p > 0.05). Although the total activated cortical areas were larger in early than late bilinguals, the activation volumes were not significantly different. Conclusion Activated brains areas in early and late fluent bilinguals largely overlapped. However, these areas were more scattered upon presentation of L2 than L1, and L1 had a more specific pattern of activation than L2. For both languages, the left hemisphere was dominant. We found that L2 proficiency level rather than age of acquisition had a greater influence on which brain areas were activated with semantic processing. PMID:28123807

  20. Carbon-dioxide flow measurement in geodynamically active area of West Bohemia

    NASA Astrophysics Data System (ADS)

    Vlcek, Josef; Fischer, Tomas; Heinicke, Jens

    2016-04-01

    Geodynamically active area of West Bohemia is interesting not only due to its earthquake swarms occurrence but also due to degassing flux of magmatic origin occurring in natural moffettes and mineral springs. While monitoring of earthquakes is done by a standard local seismic network, monitoring of amount of CO2 is at its initial stage. Despite lack of data, the 2014 earthquake swarm showed also very interesting increase in CO2 flow. This correlation with seismicity motivated us to develop robust and reliable methods of CO2 flow measurement, which would be sufficient to create denser monitoring network. Standard usage of gas-flowmeter for the purpose of gas flow measurement is dependent on the weather and device conditions, which makes the measurement instable in time and unreliable. Although gas-flowmeter is also accompanied with measurement of the gas pressure in the well to check flow rate value, reliability of this method is still low. This problematic behavior of the flow measurement was the reason to test new methods to measure CO2 amount - the first is based on measuring the density water with bubbles in the well by differential pressure gauge. The second one utilizes electric conductivity measurement to determine the density of bubbles in the water-gas mixture. Advantage of these methods is that their probes are directly in the well or moffette, where the concentration is measured. This approach is free of the influence of moving parts and assures the independence of measurements of environmental conditions. In this paper we show examples of obtained data series from selected sites and compare the trend of the curves, the mutual relations of the measured quantities and the influence of environmental conditions.

  1. Active flow control of subsonic flow in an adverse pressure gradient using synthetic jets and passive micro flow control devices

    NASA Astrophysics Data System (ADS)

    Denn, Michael E.

    Several recent studies have shown the advantages of active and/or passive flow control devices for boundary layer flow modification. Many current and future proposed air vehicles have very short or offset diffusers in order to save vehicle weight and create more optimal vehicle/engine integration. Such short coupled diffusers generally result in boundary layer separation and loss of pressure recovery which reduces engine performance and in some cases may cause engine stall. Deployment of flow control devices can alleviate this problem to a large extent; however, almost all active flow control devices have some energy penalty associated with their inclusion. One potential low penalty approach for enhancing the diffuser performance is to combine the passive flow control elements such as micro-ramps with active flow control devices such as synthetic jets to achieve higher control authority. The goal of this dissertation is twofold. The first objective is to assess the ability of CFD with URANS turbulence models to accurately capture the effects of the synthetic jets and micro-ramps on boundary layer flow. This is accomplished by performing numerical simulations replicating several experimental test cases conducted at Georgia Institute of Technology under the NASA funded Inlet Flow Control and Prediction Technologies Program, and comparing the simulation results with experimental data. The second objective is to run an expanded CFD matrix of numerical simulations by varying various geometric and other flow control parameters of micro-ramps and synthetic jets to determine how passive and active control devices interact with each other in increasing and/or decreasing the control authority and determine their influence on modification of boundary layer flow. The boundary layer shape factor is used as a figure of merit for determining the boundary layer flow quality/modification and its tendency towards separation. It is found by a large number of numerical experiments and

  2. Effect of Activating Agent on the Preparation of Bamboo-Based High Surface Area Activated Carbon by Microwave Heating

    NASA Astrophysics Data System (ADS)

    Xia, Hongying; Wu, Jian; Srinivasakannan, Chandrasekar; Peng, Jinhui; Zhang, Libo

    2016-06-01

    The present work attempts to convert bamboo into a high surface area activated carbon via microwave heating. Different chemical activating agents such as KOH, NaOH, K2CO3 and Na2CO3 were utilized to identify a most suitable activating agent. Among the activating agents tested KOH was found to generate carbon with the highest porosity and surface area. The effect of KOH/C ratio on the porous nature of the activated carbon has been assessed. An optimal KOH/C ratio of 4 was identified, beyond which the surface area as well as the pore volume were found to decrease. At the optimized KOH/C ratio the surface area and the pore volume were estimated to be 3,441 m2/g and 2.093 ml/g, respectively, with the significant proportion of which being microporous (62.3%). Activated carbon prepared under the optimum conditions was further characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Activated carbons with so high surface area and pore volume are very rarely reported, which could be owed to the nature of the precursor and the optimal conditions of mixture ratio adopted in the present work.

  3. The impact of mining activities on Mongolia's protected areas: a status report with policy recommendations.

    PubMed

    Farrington, John D

    2005-07-01

    Mongolia's protected areas cover 20.5 million ha or 13.1% of its national territory. Existing and proposed protected areas, however, are threatened by mining. Mining impacts on Mongolia's protected areas are diverse and include licensed and unlicensed mineral activities in protected areas, buffer zone disturbance, and prevention of the establishment of proposed protected areas. Review of United States, Canadian, and Australian policies revealed 9 basic approaches to resolving conflicts between protected areas and mining. Four approaches suitable for Mongolia are granting land trades and special dispensations in exchange for mineral licenses in protected areas; granting protected status to all lapsed mineral licenses in protected areas; voluntary forfeiting of mineral licenses in protected areas in exchange for positive corporate publicity; and prohibiting all new mineral activities in existing and proposed protected areas. Mining is Mongolia's most important industry, however, and the long-term benefits of preserving Mongolia's natural heritage must be considered and weighed against the economic benefits and costs of mining activities.

  4. Prediction of prognosis of ALS: Importance of active denervation findings of the cervical-upper limb area and trunk area.

    PubMed

    Sato, Yoko; Nakatani, Eiji; Watanabe, Yasuhiro; Fukushima, Masanori; Nakashima, Kenji; Kannagi, Mari; Kanatani, Yasuhiro; Mizushima, Hiroshi

    2015-11-01

    Amyotrophic lateral sclerosis (ALS) is a motor neuron disease characterized by serious muscle atrophy and weakness. The purpose of this study was to find prognostic factors in patients with mild ALS using application forms for the Specified Disease Treatment Research Program in Japan. We classified ALS as mild, moderate and severe. The subjects consisted of 363 patients with mild ALS who underwent needle electromyography at registration and were followed for more than one year. Time to progression to severe ALS and time to deterioration of activities of daily living such as speech dysfunction, upper limb dysfunction, and walking disability were used as outcomes. Cox proportional hazards model analysis was performed to identify prognostic factors. Of the patients with initially mild ALS, 38.3% (139/363) had progressed severe ALS at the last follow-up. In multivariate analysis of time to progression to severe ALS, bulbar onset (hazard ratio [95% confidence interval]: 1.68 [1.13-2.49], p = 0.010), tongue atrophy (1.69 [1.14-2.51], p = 0.009), dyspnea (1.57 [1.02-2.41], p = 0.042) and active denervation findings (ADFs) of the cervical-upper limb area (1.81 [1.25-2.63], p = 0.002) emerged as prognostic factors. Furthermore ADFs in the trunk area were prognostic factors for upper limb dysfunction and walking disability (1.72 [1.05-2.81], p = 0.031, and 1.97 [1.09-3.59], p = 0.026). In conclusion ADFs of the cervical-upper limb area and trunk area were prognostic factors in ALS patients.

  5. Prediction of prognosis of ALS: Importance of active denervation findings of the cervical-upper limb area and trunk area

    PubMed Central

    Sato, Yoko; Nakatani, Eiji; Watanabe, Yasuhiro; Fukushima, Masanori; Nakashima, Kenji; Kannagi, Mari; Kanatani, Yasuhiro; Mizushima, Hiroshi

    2015-01-01

    Summary Amyotrophic lateral sclerosis (ALS) is a motor neuron disease characterized by serious muscle atrophy and weakness. The purpose of this study was to find prognostic factors in patients with mild ALS using application forms for the Specified Disease Treatment Research Program in Japan. We classified ALS as mild, moderate and severe. The subjects consisted of 363 patients with mild ALS who underwent needle electromyography at registration and were followed for more than one year. Time to progression to severe ALS and time to deterioration of activities of daily living such as speech dysfunction, upper limb dysfunction, and walking disability were used as outcomes. Cox proportional hazards model analysis was performed to identify prognostic factors. Of the patients with initially mild ALS, 38.3% (139/363) had progressed severe ALS at the last follow-up. In multivariate analysis of time to progression to severe ALS, bulbar onset (hazard ratio [95% confidence interval]: 1.68 [1.13–2.49], p = 0.010), tongue atrophy (1.69 [1.14–2.51], p = 0.009), dyspnea (1.57 [1.02–2.41], p = 0.042) and active denervation findings (ADFs) of the cervical-upper limb area (1.81 [1.25–2.63], p = 0.002) emerged as prognostic factors. Furthermore ADFs in the trunk area were prognostic factors for upper limb dysfunction and walking disability (1.72 [1.05–2.81], p = 0.031, and 1.97 [1.09–3.59], p = 0.026). In conclusion ADFs of the cervical-upper limb area and trunk area were prognostic factors in ALS patients. PMID:26668778

  6. IEEE 802.15.4 MAC with GTS transmission for heterogeneous devices with application to wheelchair body-area sensor networks.

    PubMed

    Shrestha, Bharat; Hossain, Ekram; Camorlinga, Sergio

    2011-09-01

    In wireless personal area networks, such as wireless body-area sensor networks, stations or devices have different bandwidth requirements and, thus, create heterogeneous traffics. For such networks, the IEEE 802.15.4 medium access control (MAC) can be used in the beacon-enabled mode, which supports guaranteed time slot (GTS) allocation for time-critical data transmissions. This paper presents a general discrete-time Markov chain model for the IEEE 802.15.4-based networks taking into account the slotted carrier sense multiple access with collision avoidance and GTS transmission phenomena together in the heterogeneous traffic scenario and under nonsaturated condition. For this purpose, the standard GTS allocation scheme is modified. For each non-identical device, the Markov model is solved and the average service time and the service utilization factor are analyzed in the non-saturated mode. The analysis is validated by simulations using network simulator version 2.33. Also, the model is enhanced with a wireless propagation model and the performance of the MAC is evaluated in a wheelchair body-area sensor network scenario.

  7. Method of testing active latent-heat storage devices based on thermal performance. (ASHRAE standard)

    SciTech Connect

    1985-01-26

    The purpose of this standard is to provide a standard procedure for determining the thermal performance of latent heat thermal energy storage devices used in heating, air-conditioning, and service hot water systems.

  8. PARduino: a simple and inexpensive device for logging photosynthetically active radiation.

    PubMed

    Barnard, Holly R; Findley, Matthew C; Csavina, Janae

    2014-06-01

    Photosynthetically active radiation (PAR, 400-700 nm) is one of the primary controls of forest carbon and water relations. In complex terrain, PAR has high spatial variability. Given the high cost of commercial datalogging equipment, spatially distributed measurements of PAR have been typically modeled using geographic coordinates and terrain indices. Here, we present a design for a low-cost, field-deployable device for measuring and recording PAR built around an Arduino microcontroller-named PARduino. PARduino provides for widely distributed sensor arrays and tests the feasibility of using open-source, hobbyist-grade electronics for collecting scientific data. PARduino components include a quantum sensor, an EME Systems signal converter/amplifier and an Arduino Pro Mini microcontroller. Additional components include a real-time clock, a microSD Flash memory card and a custom printed circuit board. The components were selected for ease of assembly. We found strong agreement between the PARduino datalogger system and National Institute of Standards and Technology traceable sensors logged by an industry standard datalogger (slope = 0.99, SE < 0.01, P < 0.01; intercept = - 14.84, SE = 0.78, P < 0.01). The average difference between the two systems was 22.0 µmol m(-2) s(-1) with PARduino typically underestimating PAR. The average percentage difference between systems was 3.49%. On average, PARduino performed within the factory absolute calibration of the PAR sensor; however, larger errors occurred at low PAR levels. Using open-source technologies such as this can make it possible to develop a spatially distributed sensor network within the constraints of a typical research budget.

  9. MIDAS prototype Multispectral Interactive Digital Analysis System for large area earth resources surveys. Volume 2: Charge coupled device investigation

    NASA Technical Reports Server (NTRS)

    Kriegler, F.; Marshall, R.; Sternberg, S.

    1976-01-01

    MIDAS is a third-generation, fast, low cost, multispectral recognition system able to keep pace with the large quantity and high rates of data acquisition from large regions with present and projected sensors. MIDAS, for example, can process a complete ERTS frame in forty seconds and provide a color map of sixteen constituent categories in a few minutes. A principal objective of the MIDAS Program is to provide a system well interfaced with the human operator and thus to obtain large overall reductions in turn-around time and significant gains in throughput. The need for advanced onboard spacecraft processing of remotely sensed data is stated and approaches to this problem are described which are feasible through the use of charge coupled devices. Tentative mechanizations for the required processing operations are given in large block form. These initial designs can serve as a guide to circuit/system designers.

  10. Somatotopical relationships between cortical activity and reflex areas in reflexology: a functional magnetic resonance imaging study.

    PubMed

    Nakamaru, Tomomi; Miura, Naoki; Fukushima, Ai; Kawashima, Ryuta

    2008-12-19

    We examined the somatotopical relationship between cortical activity and sensory stimulation of reflex areas in reflexology using functional magnetic resonance imaging. Three reflex areas on the left foot, relating to the eye, shoulder, and small intestine were stimulated during the experiment. A statistical analysis showed that reflexological stimulation of the foot reflex areas corresponding to the eye, shoulder, and small intestine activated not only the somatosensory areas corresponding to the foot, but also the somatosensory areas corresponding to the eye, shoulder, and small intestine or neighboring body parts. Thus, the findings showed that reflexological stimulation induced a somatosensory process corresponding to the stimulated reflex area and that a neuroimaging approach can be used to examine the basis of reflexology effects.

  11. Nematic and blue phase liquid crystals for temperature stabilization and active optical tuning of silicon photonic devices (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Ptasinski, Joanna N.; Khoo, Iam Choon; Fainman, Yeshaiahu

    2015-10-01

    We describe the underlying theories and experimental demonstrations of passive temperature stabilization of silicon photonic devices clad in nematic liquid crystal mixtures, and active optical tuning of silicon photonic resonant structures combined with dye-doped nematic and blue phase liquid crystals. We show how modifications to the resonator device geometry allow for not only enhanced tuning of the resonator response, but also aid in achieving complete athermal operations of silicon photonic circuits. [Ref.: I.C. Khoo, "DC-field-assisted grating formation and nonlinear diffractions in methyl-red dye-doped blue phase liquid crystals," Opt. Lett. 40, 60-63 (2015); J. Ptasinski, I.C. Khoo, and Y. Fainman, "Enhanced optical tuning of modified-geometry resonators clad in blue phase liquid crystals," Opt. Lett. 39, 5435-5438 (2014); J. Ptasinski, I.C. Khoo, and Y. Fainman, "Passive Temperature Stabilization of Silicon Photonic Devices Using Liquid Crystals," Materials 7(3), 2229-2241 (2014)].

  12. Use of Activation Technique and MCNP Calculations for Measurement of Fast Neutron Spatial Distribution at the MJ Plasma Focus Device.

    NASA Astrophysics Data System (ADS)

    Bienkowska, B.; Scholz, M.; Wincel, K.; Zaręba, B.

    2008-03-01

    In this paper Plasma-Focus (PF) neutron emission properties have been studied using Monte Carlo calculations for neutron and photon transport. A Thermal Neutron Scaling Factor as a function of angular position of silver activation detectors placed around MJ Plasma Focus (PF-1000) device has been calculated. Detector responses calculated for 2.5 MeV neutrons and neutrons produced by Am-Be calibration source have been obtained .The results have shown the detector response dependence on the kind of calibration neutron source and on local geometrical/structural characteristics of the PF-1000 devices. Thus the proper calibration procedure ought to be performed for correct measurement of neutron yield within Plasma-Focus devices.

  13. Estimating Accuracy at Exercise Intensities: A Comparative Study of Self-Monitoring Heart Rate and Physical Activity Wearable Devices

    PubMed Central

    Dooley, Erin E; Golaszewski, Natalie M

    2017-01-01

    Background Physical activity tracking wearable devices have emerged as an increasingly popular method for consumers to assess their daily activity and calories expended. However, whether these wearable devices are valid at different levels of exercise intensity is unknown. Objective The objective of this study was to examine heart rate (HR) and energy expenditure (EE) validity of 3 popular wrist-worn activity monitors at different exercise intensities. Methods A total of 62 participants (females: 58%, 36/62; nonwhite: 47% [13/62 Hispanic, 8/62 Asian, 7/62 black/ African American, 1/62 other]) wore the Apple Watch, Fitbit Charge HR, and Garmin Forerunner 225. Validity was assessed using 2 criterion devices: HR chest strap and a metabolic cart. Participants completed a 10-minute seated baseline assessment; separate 4-minute stages of light-, moderate-, and vigorous-intensity treadmill exercises; and a 10-minute seated recovery period. Data from devices were compared with each criterion via two-way repeated-measures analysis of variance and Bland-Altman analysis. Differences are expressed in mean absolute percentage error (MAPE). Results For the Apple Watch, HR MAPE was between 1.14% and 6.70%. HR was not significantly different at the start (P=.78), during baseline (P=.76), or vigorous intensity (P=.84); lower HR readings were measured during light intensity (P=.03), moderate intensity (P=.001), and recovery (P=.004). EE MAPE was between 14.07% and 210.84%. The device measured higher EE at all stages (P<.01). For the Fitbit device, the HR MAPE was between 2.38% and 16.99%. HR was not significantly different at the start (P=.67) or during moderate intensity (P=.34); lower HR readings were measured during baseline, vigorous intensity, and recovery (P<.001) and higher HR during light intensity (P<.001). EE MAPE was between 16.85% and 84.98%. The device measured higher EE at baseline (P=.003), light intensity (P<.001), and moderate intensity (P=.001). EE was not

  14. 78 FR 35612 - Agency Information Collection Activities; Comment Request; Targeted Teacher Shortage Areas...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-13

    ... Agency Information Collection Activities; Comment Request; Targeted Teacher Shortage Areas Nationwide... to this notice will be considered public records. Title of Collection: Targeted Teacher Shortage... Family Education Loan Programs (FFELP) regulations, which address the targeted teacher...

  15. Occurrence of polycyclic aromatic hydrocarbons in urban streams as assessed using semipermeable membrane devices, Dallas-Fort Worth metropolitan area, Texas

    USGS Publications Warehouse

    Moring, J. Bruce

    1996-01-01

    The objectives of this fact sheet are to summarize the occurrence of water-borne PAHs in three urban streams in the Dallas- Fort Worth metropolitan area and to assess the use of semipermeable membrane devices (SPMDs) as PAH samplers. One site on each of three streams was selected for monitoring the occurrence of PAHs (fig. 1). The sites were chosen to reflect varied urban land uses and the influences of point- and nonpointsource pollution. The monitoring was done using SPMDs during a 30-day period in late May and June 1994.

  16. COMPARISON OF TRUNK AND LOWER EXTREMITY MUSCLE ACTIVITY AMONG FOUR STATIONARY EQUIPMENT DEVICES: UPRIGHT BIKE, RECUMBENT BIKE, TREADMILL, AND ELLIPTIGO®

    PubMed Central

    Baker, Ryan; Gibson, Chris; Kearney, Andrew; Busemeyer, Tommy

    2016-01-01

    Background Stationary equipment devices are often used to improve fitness. The ElliptiGO® was recently developed that blends the elements of an elliptical trainer and bicycle, allowing reciprocal lower limb pedaling in an upright position. However, it is unknown whether the muscle activity used for the ElliptiGO® is similar to walking or cycling. To date, there is no information comparing muscle activity for exercise on the treadmill, stationary upright and recumbent bikes, and the ElliptiGO®. Purpose/Hypothesis The purpose of this study was to assess trunk and lower extremity muscle activity among treadmill walking, cycling (recumbent and upright) and the ElliptiGO® cycling. It was hypothesized that the ElliptiGO® and treadmill would elicit similar electromyographic muscle activity responses compared to the stationary bike and recumbent bike during an exercise session. Study Design Cohort, repeated measures Methods Twelve recreationally active volunteers participated in the study and were assigned a random order of exercise for each of the four devices (ElliptiGO®, stationary upright cycle ergometer, recumbent ergometer, and a treadmill). Two-dimensional video was used to monitor the start and stop of exercise and surface electromyography (SEMG) were used to assess muscle activity during two minutes of cycling or treadmill walking at 40-50% heart rate reserve (HRR). Eight muscles on the dominant limb were used for analysis: gluteus maximus (Gmax), gluteus medius (Gmed), biceps femoris (BF), lateral head of the gastrocnemius (LG), tibialis anterior (TA), rectus femoris (RF). Two trunk muscles were assessed on the same side; lumbar erector spinae at L3-4 level (LES) and rectus abdominus (RA). Maximal voluntary isometric contractions (MVIC) were determined for each muscle and SEMG data were expressed as %MVIC in order to normalize outputs. Results The %MVIC for RF during ElliptiGO® cycling was higher than recumbent cycling. The LG muscle activity was highest

  17. High surface area microporous activated carbons prepared from Fox nut (Euryale ferox) shell by zinc chloride activation

    NASA Astrophysics Data System (ADS)

    Kumar, Arvind; Mohan Jena, Hara

    2015-11-01

    High surface area microporous activated carbon has been prepared from Fox nutshell (Euryale ferox) by chemical activation with ZnCl2 as an activator. The process has been conducted at different impregnation (ZnCl2/Fox nutshell) ratios (1-2.5) and carbonization temperatures (500-700 °C). The thermal decomposition behavior of Fox nutshell and impregnated Fox nutshell has been carried out by thermogravimetric analysis. The pore properties including the BET surface area, micropore surface area, micropore volume, and pore size distribution of the activated carbons have been determined by nitrogen adsorption-desorption isotherms at -196 °C using the BET, t-plot method, DR, and BJH methods. The BET surface area, the microporous surface area, total pore volume, and micropore volume have been obtained as 2869 m2/g, 2124 m2/g, 1.96 cm3/g, and 1.68 cm3/g, respectively, and the microporosity percentage of the prepared activated carbon is 85.71%. The prepared activated carbons have been also characterized with instrumental methods such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM).

  18. 32 CFR Appendix C to Part 552 - Authorized Activities for Fort Lewis Maneuver Area Access

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Area Access C Appendix C to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF.... 552, App. C Appendix C to Part 552—Authorized Activities for Fort Lewis Maneuver Area Access Military... vehicle tracks Walking, distance running Model airplane and rocket flying Model boating Orienteering...

  19. 32 CFR Appendix C to Part 552 - Authorized Activities for Fort Lewis Maneuver Area Access

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Area Access C Appendix C to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF.... 552, App. C Appendix C to Part 552—Authorized Activities for Fort Lewis Maneuver Area Access Military... vehicle tracks Walking, distance running Model airplane and rocket flying Model boating Orienteering...

  20. 32 CFR Appendix C to Part 552 - Authorized Activities for Fort Lewis Maneuver Area Access

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Area Access C Appendix C to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF.... 552, App. C Appendix C to Part 552—Authorized Activities for Fort Lewis Maneuver Area Access Military... vehicle tracks Walking, distance running Model airplane and rocket flying Model boating Orienteering...

  1. 32 CFR Appendix D to Part 552 - Unauthorized Activities in Fort Lewis Maneuver Areas

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Areas D Appendix D to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Pt. 552, App. D Appendix D to Part 552—Unauthorized Activities in Fort Lewis Maneuver Areas Civilian...

  2. 32 CFR Appendix D to Part 552 - Unauthorized Activities in Fort Lewis Maneuver Areas

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Areas D Appendix D to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Pt. 552, App. D Appendix D to Part 552—Unauthorized Activities in Fort Lewis Maneuver Areas Civilian...

  3. 32 CFR Appendix D to Part 552 - Unauthorized Activities in Fort Lewis Maneuver Areas

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Areas D Appendix D to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Pt. 552, App. D Appendix D to Part 552—Unauthorized Activities in Fort Lewis Maneuver Areas Civilian...

  4. 32 CFR Appendix D to Part 552 - Unauthorized Activities in Fort Lewis Maneuver Areas

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Areas D Appendix D to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Pt. 552, App. D Appendix D to Part 552—Unauthorized Activities in Fort Lewis Maneuver Areas Civilian...

  5. Rx for Formula Poetry in the Content Area: An Activities Book.

    ERIC Educational Resources Information Center

    Pino, Cynthia L.

    Intended for teachers in all content areas, this guide provides activities for teaching formula poetry (poetry written according to a defined format) in all subject areas. First, a rationale for why teachers should include writing in their classrooms is presented. Next, the stages of the writing process are explained and the benefits of formula…

  6. 32 CFR Appendix D to Part 552 - Unauthorized Activities in Fort Lewis Maneuver Areas

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Areas D Appendix D to Part 552 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY MILITARY RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Pt. 552, App. D Appendix D to Part 552—Unauthorized Activities in Fort Lewis Maneuver Areas Civilian...

  7. Evaluation of a bedside device to assess the activated partial thromboplastin time for heparin monitoring in infants.

    PubMed

    Klein, Richard H; van der Vorst, Marja M J; de Wilde, Rob B P; Hogenbirk, Karin; de Kam, Marieke L; Burggraaf, Jacobus

    2013-04-01

    To determine the relationship between the activated partial thromboplastin time (aPTT) measured with a standard laboratory assay and the aPTT measured with a bedside device in infants on heparin therapy after cardiothoracic surgery. Twenty infants aged below 1 year who were on heparin therapy were included. Exclusion criteria were prematurity, dysmaturity and the use of anticoagulants other than heparin. Nineteen samples were obtained from four adults in intensive care who were on heparin. The aPTT values were analyzed with the Coaguchek Pro/DM bedside device (aPTTbed) and compared with the aPTT values obtained from the laboratory Electra 1800C coagulation analyzer (aPTTlab). Correlation analysis was performed by linear regression. The agreement was calculated using Bland-Altman analysis. The correlation coefficient of samples obtained from infants was lower (r = 0.48) compared with samples from adults (r = 0.85). A substantial positive bias (27 s) and scatter [95% confidence interval (CI) -11; +65 s) was found. The bias showed a genuine trend to increase at higher aPTT values (r = 0.90; P < 0.001). The bedside device overestimates the aPTT in infants treated with heparin. The disagreement between the bedside device and laboratory increases at higher aPTTs. Bedside devices should not be used to monitor heparin therapy in infants in intensive care.

  8. A new way towards high-efficiency thermally activated delayed fluorescence devices via external heavy-atom effect

    NASA Astrophysics Data System (ADS)

    Zhang, Wenzhi; Jin, Jiangjiang; Huang, Zhi; Zhuang, Shaoqing; Wang, Lei

    2016-07-01

    Thermally activated delayed fluorescence (TADF) mechanism is a significant method that enables the harvesting of both triplet and singlet excitons for emission. However, up to now most efforts have been devoted to dealing with the relation between singlet-triplet splitting (ΔEST) and fluorescence efficiency, while the significance of spin-orbit coupling (SOC) is usually ignored. In this contribution, a new method is developed to realize high-efficiency TADF-based devices through simple device-structure optimizations. By inserting an ultrathin external heavy-atom (EHA) perturber layer in a desired manner, it provides useful means of accelerating the T1 → S1 reverse intersystem crossing (RISC) in TADF molecules without affecting the corresponding S1 → T1 process heavily. Furthermore, this strategy also promotes the utilization of host triplets through Förster mechanism during host → guest energy transfer (ET) processes, which helps to get rid of the solely dependence upon Dexter mechanism. Based on this strategy, we have successfully raised the external quantum efficiency (EQE) in 4CzPN-based devices by nearly 38% in comparison to control devices. These findings provide keen insights into the role of EHA played in TADF-based devices, offering valuable guidelines for utilizing certain TADF dyes which possess high radiative transition rate but relatively inefficient RISC.

  9. Coupled variability in primary sensory areas and the hippocampus during spontaneous activity

    PubMed Central

    de Vasconcelos, Nivaldo A. P.; Soares-Cunha, Carina; Rodrigues, Ana João; Ribeiro, Sidarta; Sousa, Nuno

    2017-01-01

    The cerebral cortex is an anatomically divided and functionally specialized structure. It includes distinct areas, which work on different states over time. The structural features of spiking activity in sensory cortices have been characterized during spontaneous and evoked activity. However, the coordination among cortical and sub-cortical neurons during spontaneous activity across different states remains poorly characterized. We addressed this issue by studying the temporal coupling of spiking variability recorded from primary sensory cortices and hippocampus of anesthetized or freely behaving rats. During spontaneous activity, spiking variability was highly correlated across primary cortical sensory areas at both small and large spatial scales, whereas the cortico-hippocampal correlation was modest. This general pattern of spiking variability was observed under urethane anesthesia, as well as during waking, slow-wave sleep and rapid-eye-movement sleep, and was unchanged by novel stimulation. These results support the notion that primary sensory areas are strongly coupled during spontaneous activity. PMID:28393914

  10. Installation and commissioning of a large area coating system for neutron and X-ray optical devices

    SciTech Connect

    Biswas, A. Haque, Sk. Maidul Misal, J. Sampathkumar, R.; Ajaykumar,; Bhattacharyya, D.; Sahoo, N. K.; Lagoo, K. D.; Veerapur, R. D.; Padmanabhan, M.; Puri, R. K.; Bhattacharya, Debarati

    2014-04-24

    A 9 meter long DC/RF sputtering cylindrical coating system which is designed and built indigenously for coating of neutron supermirrors and grazing incidence hard X-ray mirrors on large area substrates has been installed and commissioned recently. The performance of the system has been tested by depositing Ti films on glass substrate of 1500mm X 150mm size. By depositing Ti films on several small area c-Si substrates placed over the length and breadth of the substrate holder, and by subsequent characterization by GIXR measurement, it has been observed that films with bulk-like density and very low surface roughness can be obtained in the above system. The thickness uniformity achieved in the deposited films is within ±3.5% over the 1500mm length and within ±4.8% over the 150mm width.

  11. Aspirin Has Limited Ability to Modulate Shear-Mediated Platelet Activation Associated with Elevated Shear Stress of Ventricular Assist Devices

    PubMed Central

    Valerio, Lorenzo; Tran, Phat L.; Sheriff, Jawaad; Brengle, William; Ghosh, Ram; Chiu, Wei-Che; Redaelli, Alberto; Fiore, Gianfranco B.; Pappalardo, Federico; Bluestein, Danny; Slepian, Marvin J.

    2016-01-01

    Continuous flow ventricular assist devices (cfVADs) while effective in advanced heart failure, remain plagued by thrombosis related to abnormal flows and elevated shear stress. To limit cfVAD thrombosis, patients utilize complex anti-thrombotic regimens built upon a foundation of aspirin (ASA). While much data exists on ASA as a modulator of biochemically-mediated platelet activation, limited data exists as to the efficacy of ASA as a means of limiting shear-mediated platelet activation, particularly under elevated shear stress common within cfVADs. We investigated the ability of ASA (20, 25 and 125 μM) to limit shear-mediated platelet activation under conditions of: 1) constant shear stress (30 dyne/cm2 and 70 dyne/cm2); 2) dynamic shear stress, and 3) initial high shear exposure (70 dyne/cm2) followed by low shear exposure – i.e. a platelet sensitization protocol, utilizing a hemodynamic shearing device providing uniform shear stress in vitro. The efficacy of ASA to limit platelet activation mediated via passage through a clinical cfVAD system (DeBakey Micromed) in vitro was also studied. ASA reduced platelet activation only under conditions of low shear stress (38% reduction compared to control, n = 10, p < 0.004), with minimal protection at higher shear stress and under dynamic conditions (n = 10, p > 0.5) with no limitation of platelet sensitization. ASA had limited ability (25.6% reduction in platelet activation rate) to modulate shear-mediated platelet activation induced via cfVAD passage. These findings, while performed under “deconstructed” non-clinical conditions by utilizing purified platelets alone in vitro, provide a potential contributory mechanistic explanation for the persistent thrombosis rates experienced clinically in cfVAD patients despite ASA therapy. An opportunity exists to develop enhanced pharmacologic strategies to limit shear-mediated platelet activation at elevated shear levels associated with mechanical circulatory support

  12. Overview of the Tank Focus Area HLW Tank Retrieval Activities (Remote Operations)

    SciTech Connect

    GIBBONS, P.W.

    2001-01-01

    Several U.S. Department of Energy (DOE) sites are currently retrieving or preparing to retrieve radioactive waste from underground storage tanks with technical assistance from the Tanks Focus Area. The Tanks Focus Area is a national program that provides information and technologies to safely and effectively remediate radioactive waste stored in DOE's underground tanks. Funding for the Tanks Focus Area is provided by the DOE Offices of Science and Technology, Environmental Restoration, and Waste Management. This paper provides an overview of recent remote waste retrieval activities as well as recent successes sponsored by the Tanks Focus Area.

  13. 50 CFR 218.110 - Specified activity and specified geographical area.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... paragraph (c) of this section. (b) The taking of marine mammals by the Navy is only authorized if it occurs... not included in the Offshore area). (c) The taking of marine mammals by the Navy is only authorized if... the following mid-frequency active sonar (MFAS) sources, high frequency active sonar (HFAS)...

  14. Natural Environments, Obesity, and Physical Activity in Nonmetropolitan Areas of the United States

    ERIC Educational Resources Information Center

    Michimi, Akihiko; Wimberly, Michael C.

    2012-01-01

    Purpose: To assess the associations of the natural environment with obesity and physical activity in nonmetropolitan areas of the United States among representative samples by using 2 indices of outdoor activity potential (OAP) at the county level. Methods: We used the data from 457,820 and 473,296 noninstitutionalized adults aged over 18 years…

  15. A photovoltaic device based on a poly(phenyleneethynylene)/SWNT composite active layer.

    PubMed

    Liu, Qian; Mao, Jie; Liu, Zunfeng; Zhang, Nan; Wang, Yu; Yang, Liying; Yin, Shougen; Chen, Yongsheng

    2008-03-19

    Although research on the use of single walled carbon nanotubes (SWNTs) as the acceptor in polymer photovoltaic cells is currently making great progress, their poor dispersion in a polymer matrix has greatly hindered the overall performance of the devices. Here a novel bulk heterojunction structure based on a poly(phenyleneethynylene)/SWNT composite was designed to improve the dispersion of SWNTs in the composite based on their structural similarity and strong interaction. Better dispersion and higher performance are achieved compared with a common control device based on a poly(3-octylthiophene)/SWNT composite layer.

  16. The Resonating Arm Exerciser: design and pilot testing of a mechanically passive rehabilitation device that mimics robotic active assistance

    PubMed Central

    2013-01-01

    Background Robotic arm therapy devices that incorporate actuated assistance can enhance arm recovery, motivate patients to practice, and allow therapists to deliver semi-autonomous training. However, because such devices are often complex and actively apply forces, they have not achieved widespread use in rehabilitation clinics or at home. This paper describes the design and pilot testing of a simple, mechanically passive device that provides robot-like assistance for active arm training using the principle of mechanical resonance. Methods The Resonating Arm Exerciser (RAE) consists of a lever that attaches to the push rim of a wheelchair, a forearm support, and an elastic band that stores energy. Patients push and pull on the lever to roll the wheelchair back and forth by about 20 cm around a neutral position. We performed two separate pilot studies of the device. In the first, we tested whether the predicted resonant properties of RAE amplified a user’s arm mobility by comparing his or her active range of motion (AROM) in the device achieved during a single, sustained push and pull to the AROM achieved during rocking. In a second pilot study designed to test the therapeutic potential of the device, eight participants with chronic stroke (35 ± 24 months since injury) and a mean, stable, initial upper extremity Fugl-Meyer (FM) score of 17 ± 8 / 66 exercised with RAE for eight 45 minute sessions over three weeks. The primary outcome measure was the average AROM measured with a tilt sensor during a one minute test, and the secondary outcome measures were the FM score and the visual analog scale for arm pain. Results In the first pilot study, we found people with a severe motor impairment after stroke intuitively found the resonant frequency of the chair, and the mechanical resonance of RAE amplified their arm AROM by a factor of about 2. In the second pilot study, AROM increased by 66% ± 20% (p = 0.003). The mean FM score increase was 8.5 ± 4 pts (p = 0

  17. Drainage basin morphometry controls on the active depositional area of debris flow fans

    NASA Astrophysics Data System (ADS)

    Mihir, Monika; Wasklewicz, Thad; Malamud, Bruce

    2015-04-01

    A majority of the research on understanding the connection between alluvial fans and drainage basins to date has focused on coarse-scale relations between total fan area and drainage basin area. Here we take a new approach where we assess relationships between active fan depositional area and drainage basin morphometry using 52 debris flow fans (32 from the White Mountains and 20 from the Inyo Mountains) on the eastern side of Owens Valley, California, USA. The boundaries for fans, drainage basin and active depositional areas were delineated from 10m digital elevation models and 1 m aerial photographs. We examined the relationships between the normalised active depositional area of the fan (Afad/Af, where Afad is the fan active depositional area and Af the entire fan area) and the following four variables for drainage basin: (i) area (Adb), (ii) total stream length (Ls), (iii) relief (BHH), (iv) roughness (R). We find a statistically significant (r2 > 0.40) inverse power-law relationship between recent sediment contribution to the fan and drainage basin area (Afad/Af = 0.29Adb-0.167) drainage network length (Afad/Af = 0.39Ls-0.161) and basin relief (Afad/Af = 3.90BHH-0.401), and a statistically weak (r2 = 0.22) inverse power law with basin roughness (Afad/Af = 0.32R0.5441). Drainage basin size combined with other morphometric variables may largely determine efficiency in sediment transport and delivery to the fan surface. A large proportion of the total fan area of smaller fans are flooded by debris flow indicating less sediment storage in the drainage basins and greater efficiency in sediment delivery. The findings signify the importance of coarse-scale relationships to both long- and short-term fan evolution.

  18. Improved Reproducibility for Perovskite Solar Cells with 1 cm(2) Active Area by a Modified Two-Step Process.

    PubMed

    Shen, Heping; Wu, Yiliang; Peng, Jun; Duong, The; Fu, Xiao; Barugkin, Chog; White, Thomas P; Weber, Klaus; Catchpole, Kylie R

    2017-02-22

    With rapid progress in recent years, organohalide perovskite solar cells (PSC) are promising candidates for a new generation of highly efficient thin-film photovoltaic technologies, for which up-scaling is an essential step toward commercialization. In this work, we propose a modified two-step method to deposit the CH3NH3PbI3 (MAPbI3) perovskite film that improves the uniformity, photovoltaic performance, and repeatability of large-area perovskite solar cells. This method is based on the commonly used two-step method, with one additional process involving treating the perovskite film with concentrated methylammonium iodide (MAI) solution. This additional treatment is proved to be helpful for tailoring the residual PbI2 level to an optimal range that is favorable for both optical absorption and inhibition of recombination. Scanning electron microscopy and photoluminescence image analysis further reveal that, compared to the standard two-step and one-step methods, this method is very robust for achieving uniform and pinhole-free large-area films. This is validated by the photovoltaic performance of the prototype devices with an active area of 1 cm(2), where we achieved the champion efficiency of ∼14.5% and an average efficiency of ∼13.5%, with excellent reproducibility.

  19. Transparent organic bistable memory device with pure organic active material and Al/indium tin oxide electrode

    NASA Astrophysics Data System (ADS)

    Yook, Kyoung Soo; Lee, Jun Yeob; Kim, Sung Hyun; Jang, Jyongsik

    2008-06-01

    Transparent organic bistable memory devices (OBDs) were developed by employing indium tin oxide (ITO) as an anode and a cathode for OBD. A cathode structure of aluminum (Al)/ITO was used and bistability could be realized with pure polyphenylenevilylene based polymer active material without any metal nanoparticle. Transmittance of over 50% could be obtained in Al/ITO based OBD at an Al thickness of 10nm, and an average on/off ratio around 100 was observed.

  20. Biocompatibility Analysis of an Electrically-Activated Silver-Based Antibacterial Surface System for Medical Device Applications

    DTIC Science & Technology

    2012-12-16

    unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 non -infected patients, and in some cases these...antibacterial activity of silver and silver products has been widely investigated and implemented into medical devices in various forms for thousands of years...P. Developing an engineered antimicrobial/prophylactic system using electrically acti- vated bactericidal metals. J Mater Sci-Mater M. 2010;21(7):2103

  1. Relationship between Porcine Sperm Motility and Sperm Enzymatic Activity using Paper-based Devices.

    PubMed

    Matsuura, Koji; Huang, Han-Wei; Chen, Ming-Cheng; Chen, Yu; Cheng, Chao-Min

    2017-04-07

    Mammalian sperm motility has traditionally been analyzed to determine fertility using computer-assisted semen analysis (CASA) systems. To develop low-cost and robust male fertility diagnostics, we created a paper-based MTT assay and used it to estimate motile sperm concentration. When porcine sperm motility was inhibited using sperm enzyme inhibitors for sperm enzymes related to mitochondrial activity and glycolysis, we simultaneously recorded sperm motility and enzymatic reactivity using a portable motility analysis system (iSperm) and a paper-based MTT assay, respectively. When using our paper-based MTT-assay, we calculated the area mean value signal intensity (AMV) to evaluate enzymatic reactivity. Both sperm motility and AMV decreased following treatment with iodoacetamide (IODO) and 3-bromopyruvic acid (3BP), both of which are inhibitors of glycolytic enzymes including glyceraldehyde-3-phosphate dehydrogenase (GAPDH). We found a correlation between recorded motility using iSperm and AMV from our paper-based assay (P < 0.05), suggesting that a sperm-related enzymatic reaction is involved in sperm motility. Under this protocol, MTT reduction was coupled with catalysis of GAPDH and was promoted by electron transfer from NADH. Based on this inhibitor study, sperm motility can be estimated using our paper-based MTT-assay.

  2. Relationship between Porcine Sperm Motility and Sperm Enzymatic Activity using Paper-based Devices

    PubMed Central

    Matsuura, Koji; Huang, Han-Wei; Chen, Ming-Cheng; Chen, Yu; Cheng, Chao-Min

    2017-01-01

    Mammalian sperm motility has traditionally been analyzed to determine fertility using computer-assisted semen analysis (CASA) systems. To develop low-cost and robust male fertility diagnostics, we created a paper-based MTT assay and used it to estimate motile sperm concentration. When porcine sperm motility was inhibited using sperm enzyme inhibitors for sperm enzymes related to mitochondrial activity and glycolysis, we simultaneously recorded sperm motility and enzymatic reactivity using a portable motility analysis system (iSperm) and a paper-based MTT assay, respectively. When using our paper-based MTT-assay, we calculated the area mean value signal intensity (AMV) to evaluate enzymatic reactivity. Both sperm motility and AMV decreased following treatment with iodoacetamide (IODO) and 3-bromopyruvic acid (3BP), both of which are inhibitors of glycolytic enzymes including glyceraldehyde-3-phosphate dehydrogenase (GAPDH). We found a correlation between recorded motility using iSperm and AMV from our paper-based assay (P < 0.05), suggesting that a sperm-related enzymatic reaction is involved in sperm motility. Under this protocol, MTT reduction was coupled with catalysis of GAPDH and was promoted by electron transfer from NADH. Based on this inhibitor study, sperm motility can be estimated using our paper-based MTT-assay. PMID:28387379

  3. White-light emitting thin film electroluminescent devices with stacked SrS:Ce/CaS:Eu active layers

    NASA Astrophysics Data System (ADS)

    Ono, Yoshimasa A.; Fuyama, Moriaki; Onisawa, Ken-ichi; Tamura, Katsumi; Ando, Masahiko

    1989-12-01

    By stacking blue-green emitting SrS:Ce and red-emitting CaS:Eu active layers, white-light emitting electroluminescent (EL) devices were fabricated. Luminance improvement and EL characteristics of SrS:Ce and CaS:Eu EL devices were discussed. The electrooptical characteristics of white-light emitting EL devices with stacked SrS:Ce/CaS:Eu active layers were presented. Color changed from blue-green to white by changing the voltage or frequency. Finally, feasibility of multicolor EL devices by using the fabricated white-light emitting EL devices with color filters were discussed. UFpg5523,5527 UFid992922JAP UFttIn situ ac magnetic susceptibility of gadolinium thin films UFauF. H. SalasSUPa),b) and M. Mirabal-GarciaaSUPc) UFloInstitut fuur Atom- und Festkourperphysik, Freie Universitaut Berlin, D-1000 Berlin 33, ufquadFederal Republic of Germany UFsd(Received 27 April 1989; accepted for publication 3 August 1989) UFabWe report measurements of the ac magnetic susceptibility on Gd(0001)/W(110) thin films grown in ultrahigh vacuum. The measurements were made by using a pickup coil, in which the geometry and the number of turns were optimized. We applied an alternating magnetic field of about 2 Grms at frequencies of 180 and 340 Hz. The growth mode and the deposition rate of the Gd films were determined by performing conventional Auger electron spectroscopy during film growth. In films with thickness larger than 10 nm our technique is sensitive up to 1016 atoms/Grms , which allowed us to study the critical behavior of the magnetic susceptibility as the Curie temperature is approached from above, TT+C . A sharp maximum, which may be related to the Hopkinson effect, is observed at a temperature TH 289 K.

  4. 75 FR 57801 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-22

    ... Division of Dockets Management (HFA- 305), Food and Drug Administration, 5630 Fishers Lane, rm. 1061...-party reviewers have the ability to review a manufacturer's 510(k) of the act (21 U.S.C. 360) submission for selected devices. After reviewing a submission, the reviewer will forward a copy of the...

  5. Areas of activity in biofilms through the biospeckle and the spectral domain

    NASA Astrophysics Data System (ADS)

    Marques, J. K.; Braga, R. A.; Pereira, J.

    2010-09-01

    The dynamic laser speckle or biospeckle laser has been used to analyze the activity of biological and non-biological material by means of various statistical techniques and image processing. However, a challenge to adopt this technique is the ability to identify, in the same material, an area of low activity immersed in an environment of a higher activity. This work was carried out to evaluate the spectral approach associated to biospeckle laser technique as an alternative to identify distinct activities areas in the same material. Biofilm samples, which present well known protocols to be prepared, and a simpler structure than vegetal and animal tissues, were prepared with potato starch and corn starch with areas of different levels of moisture and were analyzed using the biospeckle laser associated with the wavelets transform in order to evaluate the data in the spectral domain. The effect of a black or white background below the samples was also tested. The image analysis was conducted using Generalized Difference and Fujii techniques before and after the implementation of the wavelets transform producing the filtration of the data. The results allowed the visualization of different activities areas in different frequency bands. The areas of activity were presented clearer than the traditional procedures without filtering. A new way to present the results of the biospeckle and the frequency domain information was proposed to enhance the visualization of a whole picture. It was also noted that the greatest contrast between areas of different activity were promoted by materials of different compositions. In some experimental configurations there were possible to tag the relationship between the frequency and depth of the active or inactive material. The influence of the color, black or white, of the background was also noticed in the results, but with white background better in some configurations and with the black better in others.

  6. Extraterritorial reach of the FCPA: recommendations for U.S. medical device companies with activities in Europe.

    PubMed

    Vollebregt, Erik

    2010-01-01

    Traditionally medical devices companies manage business compliance with anti-corruption and anti-fraud rules in a document-oriented way that does not always yield optimal results for the company. As a result, compliance issues are not optimally managed by the companies. Now that medical devices companies become ever more internationally active, they must also take into account the international dimensions of business compliance. This article intends to provide U.S. medical devices companies with activities in Europe with an insight in business compliance risks in the European Union (EU) and the risks related to U.S. statutes that may be applicable to a U.S. company's activities overseas. The article proposes a process-oriented and IT-supported way of structuring an international business compliance program, resulting in increased effectiveness of the program and increased competitiveness and risk management of the company as well as a high degree of acceptance of the procedures by the company's employees.

  7. P-Them Response for Geologically Active and Non-Active Areas

    NASA Astrophysics Data System (ADS)

    Vetrov, A.

    2011-12-01

    Time Domain Electromagnetic air-borne systems are widely used in geological exploration for minerals associated with conductive rocks, underground water resources and geological underground mapping. The newly designed P-THEM system has been test-flown at the Reid Mahaffy geological test site in Northern Ontario, Canada; and then over an area near Newmarket, north of Toronto. While the flight in Reid Mahaffy was made to verify real characteristics of the system: stability and repeatability of results, the flight over the Newmarket area was made to verify correct operation of the EM system with a magnetometer and gamma-ray spectrometer. Interesting and significant response of the TDEM observations to geological, agricultural and engineering objects were observed during the test flights. These results demonstrate a possibility of TDEM method for mineral research and environmental tasks. The Reid Mahaffy Test Site is located in the Abitibi Subprovince, immediately east of the Mattagami River Fault in Ontario, Canada. The test site was created in 1999 by the Ontario Geological Survey, initially to enable various airborne geophysical systems to demonstrate their basic performance capabilities. The general geology of the site contains known overburden thickness based on almost 50 diamond drill holes, with geological logs available for these. The survey flights over Reid Mahaffy test site were performed in April 2010. The altitude and direction tests were flown on three lines over the test survey area. The response of early times represents overburden and correlates with its known thickness. The conductive body appears on later time channels and remains detectable over noise level. The electrical inversion of the results allows distinguishing a structure of several vertical conductor slices, forming the conductive body. The Newmarket area selected for tests in June 2010 is a highly developed urban zone in the Greater Toronto Area, Ontario, Canada. Geologically, the area is

  8. Odours stimulate neuronal activity in the dorsolateral area of the hippocampal formation during path integration

    PubMed Central

    Jorge, P. E.; Phillips, J. B.; Gonçalves, A.; Marques, P. A. M.; Nĕmec, P.

    2014-01-01

    The dorsolateral area of the hippocampal formation of birds is commonly assumed to play a central role in processing information needed for geographical positioning and homing. Previous work has interpreted odour-induced activity in this region as evidence for an ‘olfactory map’. Here, we show, using c-Fos expression as a marker, that neuronal activation in the dorsolateral area of the hippocampal formation of pigeons is primarily a response to odour novelty, not to the spatial distribution of odour sources that would be necessary for an olfactory map. Pigeons exposed to odours had significantly more neurons activated in this area of the brain than pigeons exposed to filtered air with odours removed. This increased activity was observed only in response to unfamiliar odours. No change in activity was observed when pigeons were exposed to home odours. These findings are consistent with non-home odours activating non-olfactory components of the pigeon's navigation system. The pattern of neuronal activation in the triangular and dorsomedial areas of the hippocampal formation was, by contrast, consistent with the possibility that odours play a role in providing spatial information. PMID:24671977

  9. Odours stimulate neuronal activity in the dorsolateral area of the hippocampal formation during path integration.

    PubMed

    Jorge, P E; Phillips, J B; Gonçalves, A; Marques, P A M; Nĕmec, P

    2014-05-22

    The dorsolateral area of the hippocampal formation of birds is commonly assumed to play a central role in processing information needed for geographical positioning and homing. Previous work has interpreted odour-induced activity in this region as evidence for an 'olfactory map'. Here, we show, using c-Fos expression as a marker, that neuronal activation in the dorsolateral area of the hippocampal formation of pigeons is primarily a response to odour novelty, not to the spatial distribution of odour sources that would be necessary for an olfactory map. Pigeons exposed to odours had significantly more neurons activated in this area of the brain than pigeons exposed to filtered air with odours removed. This increased activity was observed only in response to unfamiliar odours. No change in activity was observed when pigeons were exposed to home odours. These findings are consistent with non-home odours activating non-olfactory components of the pigeon's navigation system. The pattern of neuronal activation in the triangular and dorsomedial areas of the hippocampal formation was, by contrast, consistent with the possibility that odours play a role in providing spatial information.

  10. Sustained attention to spontaneous thumb sensations activates brain somatosensory and other proprioceptive areas.

    PubMed

    Bauer, Clemens C C; Díaz, José-Luis; Concha, Luis; Barrios, Fernando A

    2014-06-01

    The present experiment was designed to test if sustained attention directed to the spontaneous sensations of the right or left thumb in the absence of any external stimuli is able to activate corresponding somatosensory brain areas. After verifying in 34 healthy volunteers that external touch stimuli to either thumb effectively activate brain contralateral somatosensory areas, and after subtracting attention mechanisms employed in both touch and spontaneous-sensation conditions, fMRI evidence was obtained that the primary somatosensory cortex (specifically left BA 3a/3b) becomes active when an individual is required to attend to the spontaneous sensations of either thumb in the absence of external stimuli. In addition, the left superior parietal cortex, anterior cingulate gyrus, insula, motor and premotor cortex, left dorsolateral prefrontal cortex, Broca's area, and occipital cortices were activated. Moreover, attention to spontaneous-sensations revealed an increased connectivity between BA 3a/3b, superior frontal gyrus (BA 9) and anterior cingulate cortex (BA 32), probably allowing top-down activations of primary somatosensory cortex. We conclude that specific primary somatosensory areas in conjunction with other left parieto-frontal areas are involved in processing proprioceptive and interoceptive bodily information that underlies own body-representations and that these networks and cognitive functions can be modulated by top-down attentional processes.

  11. Decoding Target Distance and Saccade Amplitude from Population Activity in the Macaque Lateral Intraparietal Area (LIP)

    PubMed Central

    Bremmer, Frank; Kaminiarz, Andre; Klingenhoefer, Steffen; Churan, Jan

    2016-01-01

    Primates perform saccadic eye movements in order to bring the image of an interesting target onto the fovea. Compared to stationary targets, saccades toward moving targets are computationally more demanding since the oculomotor system must use speed and direction information about the target as well as knowledge about its own processing latency to program an adequate, predictive saccade vector. In monkeys, different brain regions have been implicated in the control of voluntary saccades, among them the lateral intraparietal area (LIP). Here we asked, if activity in area LIP reflects the distance between fovea and saccade target, or the amplitude of an upcoming saccade, or both. We recorded single unit activity in area LIP of two macaque monkeys. First, we determined for each neuron its preferred saccade direction. Then, monkeys performed visually guided saccades along the preferred direction toward either stationary or moving targets in pseudo-randomized order. LIP population activity allowed to decode both, the distance between fovea and saccade target as well as the size of an upcoming saccade. Previous work has shown comparable results for saccade direction (Graf and Andersen, 2014a,b). Hence, LIP population activity allows to predict any two-dimensional saccade vector. Functional equivalents of macaque area LIP have been identified in humans. Accordingly, our results provide further support for the concept of activity from area LIP as neural basis for the control of an oculomotor brain-machine interface. PMID:27630547

  12. High-Tc superconducting quantum interference device recordings of spontaneous brain activity: Towards high-Tc magnetoencephalography

    NASA Astrophysics Data System (ADS)

    Öisjöen, F.; Schneiderman, J. F.; Figueras, G. A.; Chukharkin, M. L.; Kalabukhov, A.; Hedström, A.; Elam, M.; Winkler, D.

    2012-03-01

    We have performed single- and two-channel high transition temperature (high-Tc) superconducting quantum interference device (SQUID) magnetoencephalography (MEG) recordings of spontaneous brain activity in two healthy human subjects. We demonstrate modulation of two well-known brain rhythms: the occipital alpha rhythm and the mu rhythm found in the motor cortex. We further show that despite higher noise-levels compared to their low-Tc counterparts, high-Tc SQUIDs can be used to detect and record physiologically relevant brain rhythms with comparable signal-to-noise ratios. These results indicate the utility of high-Tc technology in MEG recordings of a broader range of brain activity.

  13. Burned area, active fires and biomass burning - approaches to account for emissions from fires in Tanzania

    NASA Astrophysics Data System (ADS)

    Ruecker, Gernot; Hoffmann, Anja; Leimbach, David; Tiemann, Joachim; Ng'atigwa, Charles

    2013-04-01

    Eleven years of data from the globally available MODIS burned area and the MODS Active Fire Product have been analysed for Tanzania in conjunction with GIS data on land use and cover to provide a baseline for fire activity in this East African country. The total radiated energy (FRE) emitted by fires that were picked up by the burned area and active fire product is estimated based on a spatio-temporal clustering algorithm over the burned areas, and integration of the fire radiative power from the MODIS Active Fires product over the time of burning and the area of each burned area cluster. Resulting biomass combusted by unit area based on Woosteŕs scaling factor for FRE to biomass combusted is compared to values found in the literature, and to values found in the Global Fire Emissions Database (GFED). Pyrogenic emissions are then estimated using emission factors. According to our analysis, an average of 11 million ha burn annually (ranging between 8.5 and 12.9 million ha) in Tanzania corresponding to between 10 and 14 % of Tanzaniás land area. Most burned area is recorded in the months from May to October. The land cover types most affected are woodland and shrubland cover types: they comprise almost 70 % of Tanzania's average annual burned area or 6.8 million ha. Most burning occurs in gazetted land, with an annual average of 3.7 million ha in forest reserves, 3.3 million ha in game reserves and 1.46 million ha in national parks, totalling close to 8.5 million ha or 77 % of the annual average burned area of Tanzania. Annual variability of burned area is moderate for most of the analysed classes, and in most cases there is no clear trend to be detected in burned area, except for the Lindi region were annual burned area appears to be increasing. Preliminary results regarding emissions from fires show that for larger fires that burn over a longer time, biomass burned derived through the FRP method compares well to literature values, while the integration over

  14. Underground Test Area Activity Communication/Interface Plan, Nevada National Security Site, Nevada, Revision 0

    SciTech Connect

    Farnham, Irene; Rehfeldt, Kenneth

    2016-10-01

    The purpose of this plan is to provide guidelines for effective communication and interfacing between Underground Test Area (UGTA) Activity participants, including the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) and its contractors. This plan specifically establishes the following: • UGTA mission, vision, and core values • Roles and responsibilities for key personnel • Communication with stakeholders • Guidance in key interface areas • Communication matrix

  15. [Preparation, characterization and adsorption performance of high surface area biomass-based activated carbons].

    PubMed

    Li, Kun-Quan; Li, Ye; Zheng, Zheng; Sang, Da-Zhi

    2013-01-01

    High surface area activated carbons were prepared with Spartina alterniflora and cotton stalk as raw materials and KOH as activating agent. Effects of materials type, impregnation ratio, activation temperature and heat preservation time on the yield, elemental composition and adsorptive capacity of activated carbon were studied. The properties and pore structure of the carbons were characterized with nitrogen adsorption, powder X-ray diffractometry (XRD), infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Main pore characteristics of activated carbons were analyzed by BET equation, Horvath-Kawazoe BET method and DFT method. The considerable preparation conditions are obtained as follows: impregnation ratio of 3: 1, an activation temperature of 800 degrees C and an activation time of 1.5 h. The BET surface area of activated carbon prepared from Spartina alterniflora reached 2 825 m2 x g(-1) when its total pore volume, yield, iodine number and methylene blue adsorption were 1.374 cm3 x g(-1), 16.36%, 1797 mg x g(-1) and 495 mg x g(-1) respectively under above conditions. The activated carbon from cotton stalk was prepared with BET surface area of 2 135 m2 x g(-1), total pore volume of 1.038 cm3 x g(-1), yield of 11.22%, methylene blue adsorption of 1 251 mg x g(-1), and iodine number of 478 mg x g(-1), respectively. The methylene blue adsorption and iodine number are much higher than the national first level for activated carbon. The Langmuir maximum adsorption capacities of 2,4-dinitrophenol on the two carbons were 932 mg x g(-1) and 747 mg x g(-1), respectively, which are superior to ordinary activated carbon and activated carbon fiber.

  16. Effect of Copolymer Chain Architecture on Active Layer Morphology and Device Performance

    NASA Astrophysics Data System (ADS)

    Amonoo, Jojo; Li, Anton; Sykes, Matthew; Huang, Bingyuan; Palermo, Edmund; McNeil, Anne; Shtein, Max; Green, Peter

    2014-03-01

    The optimum morphological structure that determines the device performance of bulk heterojunction thin film polymer solar cells is greatly influenced by the extent of phase separation between the polymer and fullerene components, which ultimately defines the length scales and purity of the donor- and acceptor-rich phases. Block copolymer thin films have been widely studied for their ability to microphase separate into well-defined nanostructures. Nickel-catalyzed chain-growth copolymerizations of thiophene and selenophene derivatives afforded well-defined π-conjugated copolymers of poly(3-hexylthiophene) (P3HT) and poly(3-hexylselenophene) (P3HS) to achieve diblock, random and gradient copolymer chain architectures. This allowed us to study the effect of copolymer sequence and nanoscale morphology of P3HT-P3HS copolymer/[6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) on device performance. With the use of energy-filtered transmission electron microscopy and conductive and photoconductive atomic force microscopy we found that copolymer sequence strongly influences the phase separation capabilities of the copolymer-fullerene blend in bulk heterojunction organic photovoltaic devices.

  17. Creation of cavitation activity in a microfluidic device through acoustically driven capillary waves.

    PubMed

    Tandiono; Ohl, Siew-Wan; Ow, Dave Siak-Wei; Klaseboer, Evert; Wong, Victor V T; Camattari, Andrea; Ohl, Claus-Dieter

    2010-07-21

    We present a study on achieving intense acoustic cavitation generated by ultrasonic vibrations in polydimethylsiloxane (PDMS) based microfluidic devices. The substrate to which the PDMS is bonded was forced into oscillation with a simple piezoelectric transducer attached at 5 mm from the device to a microscopic glass slide. The transducer was operated at 100 kHz with driving voltages ranging between 20 V and 230 V. Close to the glass surface, pressure and vibration amplitudes of up to 20 bar and 400 nm were measured respectively. It is found that this strong forcing leads to the excitation of nonlinear surface waves when gas-liquid interfaces are present in the microfluidic channels. Also, it is observed that nuclei leading to intense inertial cavitation are generated by the entrapment of gas pockets at those interfaces. Subsequently, cavitation bubble clusters with void fractions of more than 50% are recorded with high-speed photography at up to 250,000 frames/s. The cavitation clusters can be sustained through the continuous injection of gas using a T-junction in the microfluidic device.

  18. Coherent Bremsstrahlung effect observed during STEM analysis of dopant distribution in silicon devices using large area silicon drift EDX detectors and high brightness electron source.

    PubMed

    Pantel, R

    2011-11-01

    In this paper, during dopant analysis of silicon devices, we have observed a phenomenon generally neglected in EDX analysis: the coherent Bremsstrahlung (CB). We discussed the reason why and came to the conclusion that the analytical TEM used for these experiments presents a configuration and performances, which makes this equipment very sensitive to the CB effect. This is due to large collection solid angle and high counting rate of the four silicon drift EDX detectors (SDD), a high brightness electron source providing large probe current and moreover a geometry favorable to on axis crystal observations. We analyzed silicon devices containing Si [110] and Si [100] crystal areas at different energies (80-120-200keV). We also observed relaxed SiGe (27 and 40at% of Ge). The CB effect, whose intensity is maximum near zone axis beam alignment, manifests as characteristic broad peaks present in the X-ray spectrum background. The peak energies are predicted by a simple formula deduced for the CB models found in the literature and that we present simply. We evaluate also the CB peak intensities and discuss the importance of this effect on the detection and quantification traces of impurities. The CB peaks also give information on the analyzed crystal structure (measurement of the periodicity along the zone axis) and allow, in every particular experiment or system, to determine the median take off angle of the EDX detectors.

  19. Terahertz generation and detection with InGaAs-based large-area photoconductive devices excited at 1.55 μm

    SciTech Connect

    Xu, Ming; Mittendorff, Martin; Helm, Manfred; Dietz, Roman J. B.; Künzel, Harald; Sartorius, Bernd; Göbel, Thorsten; Schneider, Harald; Winnerl, Stephan

    2013-12-16

    We report on scalable large-area terahertz emitters and detectors based on In{sub 0.53}Ga{sub 0.47}As/In{sub 0.52}Al{sub 0.48}As heterostructures for excitation with 1.55 μm radiation. Different geometries involving three different electrode gap sizes are compared with respect to terahertz (THz) emission, bias field distribution, and Joule heating. The field distribution becomes more favorable for THz emission as gap size increases, while Joule heating exhibits the opposite dependence. Devices with three different gap sizes, namely 3 μm, 5 μm, and 7.5 μm, have been investigated experimentally, the emitter with a gap size of 7.5 μm showed the best performance. The scalable devices are furthermore employed as detectors. The scalable electrode geometry enables spatially integrated detection, which is attractive for specific applications, e.g., where an unfocused THz beam has to be used.

  20. Active layers of high-performance lead zirconate titanate at temperatures compatible with silicon nano- and microeletronic [corrected] devices.

    PubMed

    Bretos, Iñigo; Jiménez, Ricardo; Tomczyk, Monika; Rodríguez-Castellón, Enrique; Vilarinho, Paula M; Calzada, M Lourdes

    2016-02-03

    Applications of ferroelectric materials in modern microelectronics will be greatly encouraged if the thermal incompatibility between inorganic ferroelectrics and semiconductor devices is overcome. Here, solution-processable layers of the most commercial ferroelectric compound--morphotrophic phase boundary lead zirconate titanate, namely Pb(Zr0.52Ti0.48)O3 (PZT)--are grown on silicon substrates at temperatures well below the standard CMOS process of semiconductor technology. The method, potentially transferable to a broader range of Zr:Ti ratios, is based on the addition of crystalline nanoseeds to photosensitive solutions of PZT resulting in perovskite crystallization from only 350 °C after the enhanced decomposition of metal precursors in the films by UV irradiation. A remanent polarization of 10.0 μC cm(-2) is obtained for these films that is in the order of the switching charge densities demanded for FeRAM devices. Also, a dielectric constant of ~90 is measured at zero voltage which exceeds that of current single-oxide candidates for capacitance applications. The multifunctionality of the films is additionally demonstrated by their pyroelectric and piezoelectric performance. The potential integration of PZT layers at such low fabrication temperatures may redefine the concept design of classical microelectronic devices, besides allowing inorganic ferroelectrics to enter the scene of the emerging large-area, flexible electronics.

  1. Active layers of high-performance lead zirconate titanate at temperatures compatible with silicon nano- and microelecronic devices

    NASA Astrophysics Data System (ADS)

    Bretos, Iñigo; Jiménez, Ricardo; Tomczyk, Monika; Rodríguez-Castellón, Enrique; Vilarinho, Paula M.; Calzada, M. Lourdes

    2016-02-01

    Applications of ferroelectric materials in modern microelectronics will be greatly encouraged if the thermal incompatibility between inorganic ferroelectrics and semiconductor devices is overcome. Here, solution-processable layers of the most commercial ferroelectric compound – morphotrophic phase boundary lead zirconate titanate, namely Pb(Zr0.52Ti0.48)O3 (PZT) – are grown on silicon substrates at temperatures well below the standard CMOS process of semiconductor technology. The method, potentially transferable to a broader range of Zr:Ti ratios, is based on the addition of crystalline nanoseeds to photosensitive solutions of PZT resulting in perovskite crystallization from only 350 °C after the enhanced decomposition of metal precursors in the films by UV irradiation. A remanent polarization of 10.0 μC cm‑2 is obtained for these films that is in the order of the switching charge densities demanded for FeRAM devices. Also, a dielectric constant of ~90 is measured at zero voltage which exceeds that of current single-oxide candidates for capacitance applications. The multifunctionality of the films is additionally demonstrated by their pyroelectric and piezoelectric performance. The potential integration of PZT layers at such low fabrication temperatures may redefine the concept design of classical microelectronic devices, besides allowing inorganic ferroelectrics to enter the scene of the emerging large-area, flexible electronics.

  2. Active layers of high-performance lead zirconate titanate at temperatures compatible with silicon nano- and microelecronic devices

    PubMed Central

    Bretos, Iñigo; Jiménez, Ricardo; Tomczyk, Monika; Rodríguez-Castellón, Enrique; Vilarinho, Paula M.; Calzada, M. Lourdes

    2016-01-01

    Applications of ferroelectric materials in modern microelectronics will be greatly encouraged if the thermal incompatibility between inorganic ferroelectrics and semiconductor devices is overcome. Here, solution-processable layers of the most commercial ferroelectric compound ─ morphotrophic phase boundary lead zirconate titanate, namely Pb(Zr0.52Ti0.48)O3 (PZT) ─ are grown on silicon substrates at temperatures well below the standard CMOS process of semiconductor technology. The method, potentially transferable to a broader range of Zr:Ti ratios, is based on the addition of crystalline nanoseeds to photosensitive solutions of PZT resulting in perovskite crystallization from only 350 °C after the enhanced decomposition of metal precursors in the films by UV irradiation. A remanent polarization of 10.0 μC cm−2 is obtained for these films that is in the order of the switching charge densities demanded for FeRAM devices. Also, a dielectric constant of ~90 is measured at zero voltage which exceeds that of current single-oxide candidates for capacitance applications. The multifunctionality of the films is additionally demonstrated by their pyroelectric and piezoelectric performance. The potential integration of PZT layers at such low fabrication temperatures may redefine the concept design of classical microelectronic devices, besides allowing inorganic ferroelectrics to enter the scene of the emerging large-area, flexible electronics. PMID:26837240

  3. Progress of Systematic Hands on Devices for Active Learning Methods by Visualizing ICT Tools in Physics with Milliseconds Resolution

    NASA Astrophysics Data System (ADS)

    Kobayashi, Akizo; Okiharu, Fumiko

    We are developing various systematic hands on devices for progress of active learning (AL) to improve students' conceptual understanding in physics laws. We are promoting AL methods in physics education for getting deeper conceptual understanding by using various ICT-based hands on devices and using visualizing ICT tools with milliseconds resolution. Here we investigate AL modules on collisions of big balloon pendulum with another known mass pendulum to get directly the air mass in the big balloon. We also discuss on Newton's laws of blowgun darts systems by using tapioca straws where we get definite works and energy just proportional to the length of the pipes of connected tapioca straws. These AL plans by using modules of big balloon system and blowgun-darts system are shown to be very effective for deeper conceptual understanding of Newton's Laws in almost frictionless worlds.

  4. Seasonal Variability in Boreal Wildfire Activity Associated with Landscape Patterns of Burned Area

    NASA Astrophysics Data System (ADS)

    Barrett, K. M.; Kasischke, E. S.

    2012-12-01

    Wildfire is the most prominent disturbance in the boreal forest, effecting changes in stand age and vegetation composition often over thousands of square kilometers. The effect of wildfire on ecosystem structure and function depends heavily on the seasonality of the burn, and periods of seasonally high fire activity are highly sporadic. The majority of area in Alaska that burns in a fire season does so during relatively short periods of high fire activity. These periods, which can be determined from active fire detections or fire management agency data records, are caused by elevated air temperatures and low precipitation which decrease fuel moisture and encourage the spread of fire. While fire fronts dominate during periods of low fire activity, more active periods have a higher proportion of residual burning which remains after a front has passed through. Residual burning is likely responsible for the extensive combustion of surface organic materials in the boreal forest, which can lead to post-fire changes in dominant vegetation type. Seasonal variations in fire activity are therefore an important factor in the mosaic of severity conditions across large burned areas and shifts in land cover over successional time scales. The purpose of this study is to characterize the temporal and spatial variability in periods of seasonal high fire activity that influence patterns of burned area. In large burns, unburned areas within a fire scar may serve as an important seed stock during post-fire recruitment. These areas may also feedback to future fire regimes through the preservation of more fire-resistant vegetation in unburned "islands".

  5. Occurrence and concentrations of polycyclic aromatic hydrocarbons in semipermeable membrane devices and clams in three urban streams of the Dallas-Fort Worth Metropolitan Area, Texas

    USGS Publications Warehouse

    Moring, J.B.; Rose, D.R.

    1997-01-01

    Semipermeable membrane devices (SPMDs) and Asiatic clams, Corbicula fluminea (MuLLER), were deployed at stream sites in the Dallas-Fort Worth Metropolitan Area to assess the presence of bioavailable, dissolved polycyclic aromatic hydrocarbons (PAHs). Twenty-four PAHs were detected in SPMDs, 20 of which occurred at all sites. Only three PAHs were detected in the co-deployed clams. Throughout all sites, non-alkylated PAHs were found at greater levels in SPMDs than alkylated forms. Nine of 16 Priority Pollutant PAHs were detected in SPMDs. Estimated concentrations of PAHs in water were generally two to three orders of magnitude less than standard minimum analytical reporting levels; however, for bent (a) anthracene, benzo (a) pyrene, and chrysene, estimated concentrations in water exceeded the U.S. Environmental Protection Agency's human health criteria for these carcinogens in water and aquatic organisms.

  6. Effect of hypoxia and pharmacological treatment on some enzyme activities in dog brain areas.

    PubMed

    Arrigoni, E; Benzi, G; Curti, D; Dagani, F; Gallico, S; Gorini, A; Mandelli, V; Marzatico, F; Moretti, A; Villa, R F

    1984-05-01

    The effects of nicergoline on changes in enzymatic activities induced by hypoxia and post-hypoxic recovery were studied in various brain areas of young-adult and mature Beagle dogs. In different fractions (homogenate in toto, purified mitochondria, crude synaptosomes, SM1 and SM2 synaptic mitochondria) the maximal rate (Vmax) was investigated of the more representative enzymatic activities of: a) glycolysis, b) Krebs' cycle, c) electron transfer chain, d) amino acid and acetylcholine metabolism, e) lysosomal function. The physiopathological conditions caused alterations in different enzymatic activities depending on the area and subfraction investigated. Nicergoline tended to antagonize some of these alterations. Its action was mainly on non-synaptic mitochondria by a "braking" effect on some key enzyme activities of mitochondrial metabolism (i.e. citrate synthase, cytochrome oxidase and glutamate dehydrogenase) which suggests a sparing action in the brain.

  7. Task-modulated activation and functional connectivity of the temporal and frontal areas during speech comprehension.

    PubMed

    Yue, Q; Zhang, L; Xu, G; Shu, H; Li, P

    2013-05-01

    There is general consensus in the literature that a distributed network of temporal and frontal brain areas is involved in speech comprehension. However, how active versus passive tasks modulate the activation and the functional connectivity of the critical brain areas is not clearly understood. In this study, we used functional magnetic resonance imaging (fMRI) to identify intelligibility and task-related effects in speech comprehension. Participants performed a semantic judgment task on normal and time-reversed sentences, or passively listened to the sentences without making an overt response. The subtraction analysis demonstrated that passive sentence comprehension mainly engaged brain areas in the left anterior and posterior superior temporal sulcus and middle temporal gyrus (aSTS/MTG and pSTS/MTG), whereas active sentence comprehension recruited bilateral frontal regions in addition to the aSTS/MTG and pSTS/MTG regions. Functional connectivity analysis revealed that during passive sentence comprehension, the left aSTS/MTG was functionally connected with the left Heschl's gyrus (HG) and bilateral superior temporal gyrus (STG) but no area was functionally connected with the left pSTS/MTG; during active sentence comprehension, however, both the left aSTS/MTG and pSTS/MTG were functionally connected with bilateral superior temporal and inferior frontal areas. While these results are consistent with the view that the ventral stream of the temporo-frontal network subserves semantic processing, our findings further indicate that both the activation and the functional connectivity of the temporal and frontal areas are modulated by task demands.

  8. PLASMA DEVICE

    DOEpatents

    Baker, W.R.; Brathenahl, A.; Furth, H.P.

    1962-04-10

    A device for producing a confined high temperature plasma is described. In the device the concave inner surface of an outer annular electrode is disposed concentrically about and facing the convex outer face of an inner annular electrode across which electrodes a high potential is applied to produce an electric field there between. Means is provided to create a magnetic field perpendicular to the electric field and a gas is supplied at reduced pressure in the area therebetween. Upon application of the high potential, the gas between the electrodes is ionized, heated, and under the influence of the electric and magnetic fields there is produced a rotating annular plasma disk. The ionized plasma has high dielectric constant properties. The device is useful as a fast discharge rate capacitor, in controlled thermonuclear research, and other high temperature gas applications. (AEC)

  9. Assessment of heart rate variability based on mobile device for planning physical activity

    NASA Astrophysics Data System (ADS)

    Svirin, I. S.; Epishina, E. V.; Voronin, V. V.; Semenishchev, E. A.; Solodova, E. N.; Nabilskaya, N. V.

    2015-05-01

    In this paper we present a method for the functional analysis of human heart based on electrocardiography (ECG) signals. The approach using the apparatus of analytical and differential geometry and correlation and regression analysis. ECG contains information on the current condition of the cardiovascular system as well as on the pathological changes in the heart. Mathematical processing of the heart rate variability allows to obtain a great set of mathematical and statistical characteristics. These characteristics of the heart rate are used when solving research problems to study physiological changes that determine functional changes of an individual. The proposed method implemented for up-to-date mobile Android and iOS based devices.

  10. Modeling of Power Combining in Microstrips with Active Devices for THz Applications

    DTIC Science & Technology

    2005-08-29

    Brest, F’rance, May 1999. [12] M. Shur, GaAs Devices and Circuits, Plenum Press, London, 1987. [13] E. Alekseev and D . Pavlidis , "GaN Gunn Diodes for THz...schematically in Fig. 1. Extended sections of the transmission lines (microstrips) of length d , provide the time-delayed coupling between the lumped...radiated towards the infinity x = -oo, thus, simulating the radiation of the electromagnetic waves by the antennas in three-dimensional space. d n "sd 0

  11. Noble metal nanowires: from plasmon waveguides to passive and active devices.

    PubMed

    Lal, Surbhi; Hafner, Jason H; Halas, Naomi J; Link, Stephan; Nordlander, Peter

    2012-11-20

    Using chemical synthesis, researchers can produce noble metal nanowires with highly regular, crystalline properties unachievable by alternative, top-down nanofabrication methods. Sitting at the intersection of nanochemistry and nanooptics, noble metal nanowires have generated intense and growing research interest. These nanostructures combine subwavelength transverse dimensions (50-100 nm) and longitudinal dimensions that can reach tens of micrometers or more, which makes them an ideal platform to launch surface plasmon waves by direct illumination of one end of the structure. Because of this property, researchers are using noble metal nanowires as a tool for fundamental studies of subwavelength plasmon-based optics and the properties of surface plasmon guided wave propagation in highly confined geometries below the classical optical diffraction limit. In this Account, we review some of the recent developments in plasmonic nanowire fabrication, nanowire plasmon imaging, and nanowire optical components and devices. The addition of an adjacent nanowire, substrate, or other symmetry-breaking defect can enable the direct coupling of light to and from free space to the guided waves on a nanowire structure. Such structures lead to more complex nanowire-based geometries with multiple optical inputs and outputs. Additional nanowire imaging methods are also possible: plasmon propagation on nanowires produces intense near-field diffraction, which can induce fluorescence in nearby quantum dots or photobleach adjacent molecules. When the nanowire is deposited on a dielectric substrate, the plasmon propagation along chemically synthesized nanowires exceeds 10 μm, which makes these structures useful in nonlocal applications such as remote surface-enhanced Raman spectroscopy (SERS) sensing. Nanowires can be used as passive optical devices, which include, for example, polarization manipulators, linear polarization rotators, or even broadband linear-to-circular polarization

  12. Public Parks in Hong Kong: Characteristics of Physical Activity Areas and Their Users

    PubMed Central

    Chow, Bik C.; McKenzie, Thomas L.; Sit, Cindy H. P.

    2016-01-01

    Public parks, salient locations for engaging populations in health promoting physical activity, are especially important in high-density cities. We used the System for Observing Physical Activity in Communities (SOPARC) to conduct the first-ever surveillance study of nine public parks in Hong Kong (288 observation sessions during 36 weekdays and 36 weekend days) and observed 28,585 visitors in 262 diverse areas/facilities. Parks were widely used throughout the day on weekdays and weekend days and across summer and autumn; visitor rates were among the highest seen in 24 SOPARC studies. In contrast to other studies where teens and children dominated park use, most visitors (71%) were adults and seniors. More males (61%) than females used the parks, and they dominated areas designed for sports. Over 60% of visitors were observed engaging in moderate-to-vigorous physical activity, a rate higher than other SOPARC studies. Facilities with user fees were less accessible than non-fee areas, but they provided relatively more supervised and organized activities. Assessing parks by age, gender, and physical activity can provide useful information relative to population health. This study not only provides information useful to local administrators for planning and programming park facilities relative to physical activity, but it also provides a baseline for comparison by other high-density cities. PMID:27367709

  13. 50 CFR 218.110 - Specified activity and specified geographical area.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... paragraph (c) of this section. (b) The taking of marine mammals by the Navy is only authorized if it occurs... not included in the Offshore area). (c) The taking of marine mammals by the Navy is only authorized if it occurs incidental to the following activities: (1) The use of the following mid-frequency...

  14. 36 CFR 294.26 - Other activities in Idaho Roadless Areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Other activities in Idaho Roadless Areas. 294.26 Section 294.26 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF... mechanical transport. Nothing in this subpart shall be construed as affecting the use of motorized...

  15. 36 CFR 294.26 - Other activities in Idaho Roadless Areas.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Other activities in Idaho Roadless Areas. 294.26 Section 294.26 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF... mechanical transport. Nothing in this subpart shall be construed as affecting the use of motorized...

  16. Radiomic Texture Analysis Mapping Predicts Areas of True Functional MRI Activity

    PubMed Central

    Hassan, Islam; Kotrotsou, Aikaterini; Bakhtiari, Ali Shojaee; Thomas, Ginu A.; Weinberg, Jeffrey S.; Kumar, Ashok J.; Sawaya, Raymond; Luedi, Markus M.; Zinn, Pascal O.; Colen, Rivka R.

    2016-01-01

    Individual analysis of functional Magnetic Resonance Imaging (fMRI) scans requires user-adjustment of the statistical threshold in order to maximize true functional activity and eliminate false positives. In this study, we propose a novel technique that uses radiomic texture analysis (TA) features associated with heterogeneity to predict areas of true functional activity. Scans of 15 right-handed healthy volunteers were analyzed using SPM8. The resulting functional maps were thresholded to optimize visualization of language areas, resulting in 116 regions of interests (ROIs). A board-certified neuroradiologist classified different ROIs into Expected (E) and Non-Expected (NE) based on their anatomical locations. TA was performed using the mean Echo-Planner Imaging (EPI) volume, and 20 rotation-invariant texture features were obtained for each ROI. Using forward stepwise logistic regression, we built a predictive model that discriminated between E and NE areas of functional activity, with a cross-validation AUC and success rate of 79.84% and 80.19% respectively (specificity/sensitivity of 78.34%/82.61%). This study found that radiomic TA of fMRI scans may allow for determination of areas of true functional activity, and thus eliminate clinician bias. PMID:27151623

  17. A Process of Environmental Education Communication through Community Cultural Activity Area

    ERIC Educational Resources Information Center

    Wongpaibool, Duangporn; Rawang, Wee; Supapongpichate, Ratchanont; Pichayapibool, Pataraboon

    2016-01-01

    The purpose of this research was: 1. To investigate social context, environment, way of life and community culture. 2. To gather the views and opinions regarding environmental conservation and restoration. 3. To synthesize a process of environmental education communication based on community cultural activity area. 4. To evaluate the efficacy of…

  18. 36 CFR 294.25 - Mineral activities in Idaho Roadless Areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Grassland. (1) For mineral leases, contracts, permits, and other associated activities authorized after..., and Grassland theme; except such road construction or reconstruction may be authorized by the... Roadless Areas designated as General Forest, Rangeland, and Grassland only if the use of these...

  19. 36 CFR 294.25 - Mineral activities in Idaho Roadless Areas.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Grassland. (1) For mineral leases, contracts, permits, and other associated activities authorized after..., and Grassland theme; except such road construction or reconstruction may be authorized by the... Roadless Areas designated as General Forest, Rangeland, and Grassland only if the use of these...

  20. 36 CFR 294.25 - Mineral activities in Idaho Roadless Areas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Grassland. (1) For mineral leases, contracts, permits, and other associated activities authorized after..., and Grassland theme; except such road construction or reconstruction may be authorized by the... Roadless Areas designated as General Forest, Rangeland, and Grassland only if the use of these...

  1. 36 CFR 294.25 - Mineral activities in Idaho Roadless Areas.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Grassland. (1) For mineral leases, contracts, permits, and other associated activities authorized after..., and Grassland theme; except such road construction or reconstruction may be authorized by the... Roadless Areas designated as General Forest, Rangeland, and Grassland only if the use of these...

  2. 36 CFR 294.25 - Mineral activities in Idaho Roadless Areas.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Grassland. (1) For mineral leases, contracts, permits, and other associated activities authorized after..., and Grassland theme; except such road construction or reconstruction may be authorized by the... Roadless Areas designated as General Forest, Rangeland, and Grassland only if the use of these...

  3. Stress shifts brain activation towards ventral 'affective' areas during emotional distraction.

    PubMed

    Oei, Nicole Y L; Veer, Ilya M; Wolf, Oliver T; Spinhoven, Philip; Rombouts, Serge A R B; Elzinga, Bernet M

    2012-04-01

    Acute stress has been shown to impair working memory (WM), and to decrease prefrontal activation during WM in healthy humans. Stress also enhances amygdala responses towards emotional stimuli. Stress might thus be specifically detrimental to WM when one is distracted by emotional stimuli. Usually, emotional stimuli presented as distracters in a WM task slow down performance, while evoking more activation in ventral 'affective' brain areas, and a relative deactivation in dorsal 'executive' areas. We hypothesized that after acute social stress, this reciprocal dorsal-ventral pattern would be shifted towards greater increase of ventral 'affective' activation during emotional distraction, while impairing WM performance. To investigate this, 34 healthy men, randomly assigned to a social stress or control condition, performed a Sternberg WM task with emotional and neutral distracters inside an MRI scanner. Results showed that WM performance after stress tended to be slower during emotional distraction. Brain activations during emotional distraction was enhanced in ventral affective areas, while dorsal executive areas tended to show less deactivation after stress. These results suggest that acute stress shifts priority towards processing of emotionally significant stimuli, at the cost of WM performance.

  4. Interspecies activity correlations reveal functional correspondence between monkey and human brain areas.

    PubMed

    Mantini, Dante; Hasson, Uri; Betti, Viviana; Perrucci, Mauro G; Romani, Gian Luca; Corbetta, Maurizio; Orban, Guy A; Vanduffel, Wim

    2012-02-05

    Evolution-driven functional changes in the primate brain are typically assessed by aligning monkey and human activation maps using cortical surface expansion models. These models use putative homologous areas as registration landmarks, assuming they are functionally correspondent. For cases in which functional changes have occurred in an area, this assumption prohibits to reveal whether other areas may have assumed lost functions. Here we describe a method to examine functional correspondences across species. Without making spatial assumptions, we assessed similarities in sensory-driven functional magnetic resonance imaging responses between monkey (Macaca mulatta) and human brain areas by temporal correlation. Using natural vision data, we revealed regions for which functional processing has shifted to topologically divergent locations during evolution. We conclude that substantial evolution-driven functional reorganizations have occurred, not always consistent with cortical expansion processes. This framework for evaluating changes in functional architecture is crucial to building more accurate evolutionary models.

  5. Regulatory perspectives and research activities at the FDA on the use of phantoms with in vivo diagnostic devices

    NASA Astrophysics Data System (ADS)

    Agrawal, Anant; Gavrielides, Marios A.; Weininger, Sandy; Chakrabarti, Kish; Pfefer, Joshua

    2008-02-01

    For a number of years, phantoms have been used to optimize device parameters and validate performance in the primary medical imaging modalities (CT, MRI, PET/SPECT, ultrasound). Furthermore, the FDA under the Mammography Quality Standards Act (MQSA) requires image quality evaluation of mammography systems using FDA-approved phantoms. The oldest quantitative optical diagnostic technology, pulse oximetry, also benefits from the use of active phantoms known as patient simulators to validate certain performance characteristics under different clinically-relevant conditions. As such, guidance provided by the FDA to its staff and to industry on the contents of pre-market notification and approval submissions includes suggestions on how to incorporate the appropriate phantoms in establishing device effectiveness. Research at the FDA supports regulatory statements on the use of phantoms by investigating how phantoms can be designed, characterized, and utilized to determine critical device performance characteristics. These examples provide a model for how novel techniques in the rapidly growing field of optical diagnostics can use phantoms during pre- and post-market regulatory testing.

  6. Integrated device for optical stimulation and spatiotemporal electrical recording of neural activity in light-sensitized brain tissue

    PubMed Central

    Zhang, Jiayi; Laiwalla, Farah; Kim, Jennifer A; Urabe, Hayato; Van Wagenen, Rick; Song, Yoon-Kyu; Connors, Barry W; Zhang, Feng; Deisseroth, Karl; Nurmikko, Arto V

    2010-01-01

    Neural stimulation with high spatial and temporal precision is desirable both for studying the real-time dynamics of neural networks and for prospective clinical treatment of neurological diseases. Optical stimulation of genetically targeted neurons expressing the light sensitive channel protein Channelrhodopsin (ChR2) has recently been reported as a means for millisecond temporal control of neuronal spiking activities with cell-type selectivity. This offers the prospect of enabling local delivery of optical stimulation and the simultaneous monitoring of the neural activity by electrophysiological means, both in the vicinity of and distant to the stimulation site. We report here a novel dual-modality hybrid device, which consists of a tapered coaxial optical waveguide (‘optrode’) integrated into a 100 element intra-cortical multi-electrode recording array. We first demonstrate the dual optical delivery and electrical recording capability of the single optrode in in vitro preparations of mouse retina, photo-stimulating the native retinal photoreceptors while recording light-responsive activities from ganglion cells. The dual-modality array device was then used in ChR2 transfected mouse brain slices. Specifically, epileptiform events were reliably optically triggered by the optrode and their spatiotemporal patterns were simultaneously recorded by the multi-electrode array. PMID:19721185

  7. The Importance of Landscape Elements for Bat Activity and Species Richness in Agricultural Areas

    PubMed Central

    Heim, Olga; Treitler, Julia T.; Tschapka, Marco; Knörnschild, Mirjam; Jung, Kirsten

    2015-01-01

    Landscape heterogeneity is regarded as a key factor for maintaining biodiversity and ecosystem function in production landscapes. We investigated whether grassland sites at close vicinity to forested areas are more frequently used by bats. Considering that bats are important consumers of herbivorous insects, including agricultural pest, this is important for sustainable land management. Bat activity and species richness were assessed using repeated monitoring from May to September in 2010 with acoustic monitoring surveys on 50 grassland sites in the Biosphere Reserve Schorfheide-Chorin (North-East Germany). Using spatial analysis (GIS), we measured the closest distance of each grassland site to potentially connecting landscape elements (e.g., trees, linear vegetation, groves, running and standing water). In addition, we assessed the distance to and the percent land cover of forest remnants and urban areas in a 200 m buffer around the recording sites to address differences in the local landscape setting. Species richness and bat activity increased significantly with higher forest land cover in the 200 m buffer and at smaller distance to forested areas. Moreover, species richness increased in proximity to tree groves. Larger amount of forest land cover and smaller distance to forest also resulted in a higher activity of bats on grassland sites in the beginning of the year during May, June and July. Landscape elements near grassland sites also influenced species composition of bats and species richness of functional groups (open, edge and narrow space foragers). Our results highlight the importance of forested areas, and suggest that agricultural grasslands that are closer to forest remnants might be better buffered against outbreaks of agricultural pest insects due to higher species richness and higher bat activity. Furthermore, our data reveals that even for highly mobile species such as bats, a very dense network of connecting elements within the landscape is

  8. The Importance of Landscape Elements for Bat Activity and Species Richness in Agricultural Areas.

    PubMed

    Heim, Olga; Treitler, Julia T; Tschapka, Marco; Knörnschild, Mirjam; Jung, Kirsten

    2015-01-01

    Landscape heterogeneity is regarded as a key factor for maintaining biodiversity and ecosystem function in production landscapes. We investigated whether grassland sites at close vicinity to forested areas are more frequently used by bats. Considering that bats are important consumers of herbivorous insects, including agricultural pest, this is important for sustainable land management. Bat activity and species richness were assessed using repeated monitoring from May to September in 2010 with acoustic monitoring surveys on 50 grassland sites in the Biosphere Reserve Schorfheide-Chorin (North-East Germany). Using spatial analysis (GIS), we measured the closest distance of each grassland site to potentially connecting landscape elements (e.g., trees, linear vegetation, groves, running and standing water). In addition, we assessed the distance to and the percent land cover of forest remnants and urban areas in a 200 m buffer around the recording sites to address differences in the local landscape setting. Species richness and bat activity increased significantly with higher forest land cover in the 200 m buffer and at smaller distance to forested areas. Moreover, species richness increased in proximity to tree groves. Larger amount of forest land cover and smaller distance to forest also resulted in a higher activity of bats on grassland sites in the beginning of the year during May, June and July. Landscape elements near grassland sites also influenced species composition of bats and species richness of functional groups (open, edge and narrow space foragers). Our results highlight the importance of forested areas, and suggest that agricultural grasslands that are closer to forest remnants might be better buffered against outbreaks of agricultural pest insects due to higher species richness and higher bat activity. Furthermore, our data reveals that even for highly mobile species such as bats, a very dense network of connecting elements within the landscape is

  9. Large-area flexible monolithic ITO/WO3/Nb2O5/NiVOχ/ITO electrochromic devices prepared by using magnetron sputter deposition

    NASA Astrophysics Data System (ADS)

    Tang, Chien-Jen; Ye, Jia-Ming; Yang, Yueh-Ting; He, Ju-Liang

    2016-05-01

    Electrochromic devices (ECDs) have been applied in smart windows to control the transmission of sunlight in green buildings, saving up to 40-50% electricity consumption and ultimately reducing carbon dioxide emissions. However, the high manufacturing costs and difficulty of transportation of conventional massive large area ECDs has limited widespread applications. A unique design replacing the glass substrate commonly used in the ECD windows with inexpensive, light-weight and flexible polymeric substrate materials would accelerate EC adoption allowing them to be supplemented for regular windows without altering window construction. In this study, an ITO/WO3/Nb2O5/NiVOχ/ITO all-solid-state monolithic ECD with an effective area of 24 cm × 18 cm is successfully integrated on a PET substrate by using magnetron sputter deposition. The electrochromic performance and bending durability of the resultant material are also investigated. The experimental results indicate that the ultimate response times for the prepared ECD is 6 s for coloring at an applied voltage of -3 V and 5 s for bleaching at an applied voltage of +3 V, respectively. The optical transmittances for the bleached and colored state at a wavelength of 633 nm are 53% and 11%, respectively. The prepared ECD can sustain over 8000 repeated coloring and bleaching cycles, as well as tolerate a bending radius of curvature of 7.5 cm.

  10. Compensatory activity in the extrastriate body area of Parkinson's disease patients.

    PubMed

    van Nuenen, Bart F L; Helmich, Rick C; Buenen, Noud; van de Warrenburg, Bart P C; Bloem, Bastiaan R; Toni, Ivan

    2012-07-11

    Compensatory mechanisms are a crucial component of the cerebral changes triggered by neurodegenerative disorders. Identifying such compensatory mechanisms requires at least two complementary approaches: localizing candidate areas using functional imaging, and showing that interference with these areas has behavioral consequences. Building on recent imaging evidence, we use this approach to test whether a visual region in the human occipito-temporal cortex-the extrastriate body area-compensates for altered dorsal premotor activity in Parkinson's disease (PD) during motor-related processes. We separately inhibited the extrastriate body area and dorsal premotor cortex in 11 PD patients and 12 healthy subjects, using continuous theta burst stimulation. Our goal was to test whether these areas are involved in motor compensatory processes. We used motor imagery to isolate a fundamental element of motor planning, namely subjects' ability to incorporate the current state of their body into a motor plan (mental hand rotation). We quantified this ability through a posture congruency effect (i.e., the improvement in subjects' performance when their current body posture is congruent to the imagined movement). Following inhibition of the right extrastriate body area, the posture congruency effect was lost in PD patients, but not in healthy subjects. In contrast, inhibition of the left dorsal premotor cortex reduced the posture congruency effect in healthy subjects, but not in PD patients. These findings suggest that the right extrastriate body area plays a compensatory role in PD by supporting a function that is no longer performed by the dorsal premotor cortex.

  11. Cerebellar theta burst stimulation modulates the neural activity of interconnected parietal and motor areas

    PubMed Central

    Casula, Elias Paolo; Pellicciari, Maria Concetta; Ponzo, Viviana; Stampanoni Bassi, Mario; Veniero, Domenica; Caltagirone, Carlo; Koch, Giacomo

    2016-01-01

    Voluntary movement control and execution are regulated by the influence of the cerebellar output over different interconnected cortical areas, through dentato-thalamo connections. In the present study we applied transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to directly assess the effects of cerebellar theta-burst stimulation (TBS) over the controlateral primary motor cortex (M1) and posterior parietal cortex (PPC) in a group of healthy volunteers. We found a TBS-dependent bidirectional modulation over TMS-evoked activity; specifically, cTBS increased whereas iTBS decreased activity between 100 and 200 ms after TMS, in a similar manner over both M1 and PPC areas. On the oscillatory domain, TBS induced specific changes over M1 natural frequencies of oscillation: TMS-evoked alpha activity was decreased by cTBS whereas beta activity was enhanced by iTBS. No effects were observed after sham stimulation. Our data provide novel evidence showing that the cerebellum exerts its control on the cortex likely by impinging on specific set of interneurons dependent on GABA-ergic activity. We show that cerebellar TBS modulates cortical excitability of distant interconnected cortical areas by acting through common temporal, spatial and frequency domains. PMID:27796359

  12. On the abundance and activity pattern of zoobenthos inhabiting a tropical reef area, Cebu, Philippines

    NASA Astrophysics Data System (ADS)

    Faubel, A.

    1984-12-01

    A benthic faunal study was carried out in the tidal area of Mactan Island (Cebu, Philippines). The area was subdivided along a transect from the beach to the reef according to benthic assemblages. The sediments are largely composed of calcareous skeletal remains of the indigenous biota and surrounding calcareous rocks. The content of protein and carbohydrates of the sediment was estimated, providing an approximation of organic matter in terms of feeding efficiency. Total number of zoobenthos, both as regards the sediment samples and as to the epifaunal communities associated with seaweeds, is rather uniformly distributed justifying the 95% confidence level ( P>0.05). Distinct differences are apparent in abundance values of individual taxa. Although the study area showed the expected distribution pattern, with dominance of Nematoda (39%) living in sediment and Harpacticoida (36 66%) dwelling on Thalassia and algae, Polychaeta reveal a dominant attraction to both these habitats. The reasons for this phenomenon are discussed in relation to the absolute lack of macrofaunal predators The zoobenthos adjust their distribution and activity to fluctuating conditions of the environment. Light is mainly suggested as stimulating diel migration activities of the benthic fauna, moving upwards from the sediment to the algae and Thalassia during daytime. In a field experiment the zoobenthos was investigated for digestion activity over a diurnal cycle. The results reveal that feeding activity of zoobenthos follows a diel cycle showing maximum activity during the morning and evening obviously influenced by changes of light.

  13. Comparison of the locomotor activating effects of bicuculline infusions into the preoptic area and ventral pallidum

    PubMed Central

    Zahm, Daniel S.; Schwartz, Zachary M.; Lavezzi, Heather N.; Yetnikoff, Leora; Parsley, Kenneth P.

    2013-01-01

    Ambulatory locomotion in the rodent is robustly activated by unilateral infusions into the basal forebrain of type A gamma-aminobutyric acid (GABAA) receptor antagonists, such as bicuculline and picrotoxin. The present study was carried out to better localize the neuroanatomical substrate(s) underlying this effect. To accomplish this, differences in total locomotion accumulated during a 20 minute test period following bicuculline versus saline infusions in male Sprague-Dawley rats were calculated, rank ordered and mapped on a diagram of basal forebrain transposed from immunoprocessed sections. The most robust locomotor activation was elicited by bicuculline infusions clustered in rostral parts of the preoptic area. Unilateral infusions of bicuculline into the ventral pallidum produced an unanticipatedly diminutive activation of locomotion, which led us to evaluate bilateral ventral pallidal infusions, and these also produced only a small activation of locomotion, and, interestingly, a non-significant trend toward suppression of rearing. Subjects with bicuculline infused bilaterally into the ventral pallidum also exhibited persistent bouts of abnormal movements. Bicuculline infused unilaterally into other forebrain structures, including the bed nucleus of stria terminalis, caudate-putamen, globus pallidus, sublenticular extended amygdala and sublenticular substantia innominata, did not produce significant locomotor activation. Our data identify the rostral preoptic area as the main substrate for the locomotor activating effects of basal forebrain bicuculline infusions. In contrast, slight activation of locomotion and no effect on rearing accompanied unilateral and bilateral ventral pallidal infusions. Implications of these findings for forebrain processing of reward are discussed. PMID:23423460

  14. Brain stimulation used as biofeedback in neuronal activation of the temporal lobe area in autistic children.

    PubMed

    Silva, Vernon Furtado da; Calomeni, Mauricio Rocha; Nunes, Rodolfo Alkmim Moreira; Pimentel, Carlos Elias; Martins, Gabriela Paes; Oliveira, Patrícia da Cruz Araruna; Silva, Patrícia Bagno; Silva, Alair Pedro Ribeiro de Souza E

    2016-08-01

    This study focused upon the functional capacity of mirror neurons in autistic children. 30 individuals, 10 carriers of the autistic syndrome (GCA), 10 with intellectual impairments (GDI), and 10 non-autistics (GCN) had registered eletroencephalogram from the brain area theoretically related to mirror neurons. Data collection procedure occurred prior to brain stimulation and after the stimulation session. During the second session, participants had to alternately process figures evoking neutral, happy, and/or sorrowful feelings. Results proved that, for all groups, the stimulation process in fact produced additional activation in the neural area under study. The level of activation was related to the format of emotional stimuli and the likelihood of boosting such stimuli. Since the increase of activation occurred in a model similar to the one observed for the control group, we may suggest that the difficulty people with autism have at expressing emotions is not due to nonexistence of mirror neurons.

  15. Optoelectronic device

    DOEpatents

    Bonekamp, Jeffrey E.; Boven, Michelle L.; Gaston, Ryan S.

    2014-09-09

    The invention is an optoelectronic device comprising an active portion which converts light to electricity or converts electricity to light, the active portion having a front side for the transmittal of the light and a back side opposite from the front side, at least two electrical leads to the active portion to convey electricity to or from the active portion, an enclosure surrounding the active portion and through which the at least two electrical leads pass wherein the hermetically sealed enclosure comprises at the front side of the active portion a barrier material which allows for transmittal of light, one or more getter materials disposed so as to not impede the transmission of light to or from the active portion, and a contiguous gap pathway to the getter material which pathway is disposed between the active portion and the barrier material.

  16. Imaging of Active Microwave Devices at Cryogenic Temperatures using Scanning Near-Field Microwave Microscopy

    NASA Astrophysics Data System (ADS)

    Thanawalla, Ashfaq S.; Dutta, S. K.; Vlahacos, C. P.; Steinhauer, D. E.; Feenstra, B. J.; Anlage, Steven M.; Wellstood, F. C.

    1998-03-01

    The ability to image electric fields in operating microwave devices is interesting both from the fundamental point of view and for diagnostic purposes. To that end we have constructed a scanning near-field microwave microscope which uses an open-ended coaxial probe and operates at cryogenic temperatures.(For related publications see: C. P. Vlahacos, R. C. Black, S. M. Anlage, A. Amar and F. C. Wellstood, Appl. Phys. Lett. 69), 3274 (1996) and S. M. Anlage, C. P. Vlahacos, Sudeep Dutta and F. C. Wellstood, IEEE Trans. Appl. Supercond. 7, 3686 (1997). Using this system we have imaged electric fields generated by both normal metal and superconducting microstrip resonators at temperatures ranging from 77 K to 300 K. We will present images and discuss our results including observations of clear standing wave patterns at the fundamental resonant frequency and an increased quality factor of the resonators at low temperatures.

  17. Device and programming abstractions for spatiotemporal control of active micro-particle swarms.

    PubMed

    Lam, Amy T; Samuel-Gama, Karina G; Griffin, Jonathan; Loeun, Matthew; Gerber, Lukas C; Hossain, Zahid; Cira, Nate J; Lee, Seung Ah; Riedel-Kruse, Ingmar H

    2017-03-21

    We present a hardware setup and a set of executable commands for spatiotemporal programming and interactive control of a swarm of self-propelled microscopic agents inside a microfluidic chip. In particular, local and global spatiotemporal light stimuli are used to direct the motion of ensembles of Euglena gracilis, a unicellular phototactic organism. We develop three levels of programming abstractions (stimulus space, swarm space, and system space) to create a scripting language for directing swarms. We then implement a multi-level proof-of-concept biotic game using these commands to demonstrate their utility. These device and programming concepts will enhance our capabilities for manipulating natural and synthetic swarms, with future applications for on-chip processing, diagnostics, education, and research on collective behaviors.

  18. Multiferroic domain boundaries as active memory devices: trajectories towards domain boundary engineering.

    PubMed

    Salje, Ekhard K H

    2010-04-06

    Twin boundaries in ferroelastics and curved interfaces between crystalline and amorphous zircon can, in principle, act as multiferroic structural elements and lead the way to the discovery of novel multiferroic devices which are based on structurally heterogeneous materials. While this paradigm has not yet been explored in full, this review shows that physical and chemical properties can vary dramatically inside twin boundaries and interfaces. Properties that have been already been explored include electric dipoles in a non-polar matrix, the appearance of superconductivity in twin boundaries and the catalytic reaction of hydrous species in interfaces of radiation damaged material. Some of the fundamental physical and chemical properties of twin boundaries and related interfaces are described and possible applications are outlined.

  19. Process effects on activated carbon with large specific surface area from corn cob.

    PubMed

    Cao, Qing; Xie, Ke-Chang; Lv, Yong-Kang; Bao, Wei-Ren

    2006-01-01

    The main factors that affect the large specific surface area (SSA) of the activated carbon from agricultural waste corn cobs were studied by chemically activated method with solution of KOH and soap which acted as surfactant. The experiment showed that not only the activation temperature, activation time and the mass ratio of KOH to the carbonized material, but also the activated methods using activator obviously influenced the SSA of activated carbon. The experimental operating conditions were as follows: the carbonized temperature being 450 degrees C and keeping time being 4 h using N2 as protective gas; the activation temperature being 850 degrees C and holding time being 1.2 h; the mass ratio of KOH to carbonized material being 4.0; the time of soaking carbonized material in the solution of KOH and soap being 30 min. Under the optimal conditions, the SSA of activated carbon from corn cobs reached 2700 m2/g. And the addition of the soap as surfactant may shorten the soaking time. The structure of the activated carbon prepared had narrow distribution of pore size and the micro-pores accounted for 78%. The advantages of the method described were easy and feasible.

  20. One-step fabrication of single-crystalline ZnS nanotubes with a novel hollow structure and large surface area for photodetector devices

    NASA Astrophysics Data System (ADS)

    An, Qinwei; Meng, Xianquan; Xiong, Ke; Qiu, Yunlei; Lin, Weihua

    2017-03-01

    ZnS nanotubes (NTs) were successfully prepared via a one-step thermal evaporation process without using any templates. The resulting NTs were single crystalline and structurally uniform. Based on experimental analysis, a tube-growth vapor–liquid–solid process was proposed as the growth mechanism of ZnS NTs. A metal–semiconductor–metal full-nanostructured ultraviolet (UV) photodetector with ZnS NTs as the active layer, and Ag nanowires of low resistivity and high transmissivity as electrodes, was fabricated and characterized. The ZnS NT-based device displayed a high I on/I off ratio of up to ∼1.56 × 105 with a high response to UV incident light at low operation voltage. This work is a meaningful exploration for preparing other one-dimensional semiconductor NTs, and developing a high-performance and power-saving UV sensor.

  1. Endoscopic hemostasis with an ultrasonically activated device for hemorrhage from a branch of the maxillary artery during endoscopically assisted reduction of condylar neck fracture.

    PubMed

    Iwai, Toshinori; Matsui, Yoshiro; Omura, Susumu; Tohnai, Iwai

    2013-03-01

    We describe here a case in which sudden hemorrhage from a branch of the maxillary artery during endoscopically assisted transoral reduction of condylar neck fracture was successfully controlled by endoscopic hemostasis with an ultrasonically activated device.

  2. Seasonal variation of activity patterns in roe deer in a temperate forested area.

    PubMed

    Pagon, Nives; Grignolio, Stefano; Pipia, Anna; Bongi, Paolo; Bertolucci, Cristiano; Apollonio, Marco

    2013-07-01

    We investigated the activity patterns of a European roe deer (Capreolus capreolus) population living in a forested Apennine area in central Italy, in order to shed light on the environmental and biological factors that were expected to account for the observed activity patterns on daily and yearly bases. Daily and seasonal activity patterns of 31 radio-collared roe deer were assessed through sessions of radio tracking for a total period of 18 consecutive months. Roe deer showed bimodal activity patterns throughout the year, with the two highest peaks of activity recorded at dawn and dusk. Activity patterns of males and females differed during the territorial period (from early spring to late summer), whereas they did not during the nonterritorial period. Most likely, behavioral thermoregulation can be held responsible for variation of daily activity patterns in different seasons. In winter, for instance, activity during the dawn period was significantly higher than in other seasons and daylight activity was significantly higher than at night. Nocturnal activity was highest in summer and lowest in winter. During the hunting season, moreover, roe deer showed lower activity levels than during the rest of the year. The prediction that roe deer would show lower activity levels during full moon nights, when the predation risk was assumed to be higher, was not confirmed by our data. Activity rhythms in roe deer were thus subjected to both endogenous and environmental factors, the latter working as exogenous synchronization cues. Accordingly, in changing environmental and ecological conditions, a circadian cycle of activity could be seen as the result of complex interactions among daily behavioral rhythm, digestive physiology, and external modifying factors.

  3. 78 FR 13712 - U.S. Nuclear Regulatory Commission Planned Monitoring Activities for F-Area Tank Farm at the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-28

    ... COMMISSION U.S. Nuclear Regulatory Commission Planned Monitoring Activities for F-Area Tank Farm at the... Savannah River Site F-Area Tank Farm Facility in Accordance with the National Defense Authorization Act for... DOE's waste disposal activities at the F-Area Tank Farm at the Savannah River Site, in accordance...

  4. On the area expansion of magnetic flux tubes in solar active regions

    SciTech Connect

    Dudík, Jaroslav; Dzifčáková, Elena; Cirtain, Jonathan W. E-mail: elena@asu.cas.cz

    2014-11-20

    We calculated the three-dimensional (3D) distribution of the area expansion factors in a potential magnetic field, extrapolated from the high-resolution Hinode/SOT magnetogram of the quiescent active region NOAA 11482. Retaining only closed loops within the computational box, we show that the distribution of area expansion factors show significant structure. Loop-like structures characterized by locally lower values of the expansion factor are embedded in a smooth background. These loop-like flux tubes have squashed cross-sections and expand with height. The distribution of the expansion factors show an overall increase with height, allowing an active region core characterized by low values of the expansion factor to be distinguished. The area expansion factors obtained from extrapolation of the Solar Optical Telescope magnetogram are compared to those obtained from an approximation of the observed magnetogram by a series of 134 submerged charges. This approximation retains the general flux distribution in the observed magnetogram, but removes the small-scale structure in both the approximated magnetogram and the 3D distribution of the area expansion factors. We argue that the structuring of the expansion factor can be a significant ingredient in producing the observed structuring of the solar corona. However, due to the potential approximation used, these results may not be applicable to loops exhibiting twist or to active regions producing significant flares.

  5. When Action Observation Facilitates Visual Perception: Activation in Visuo-Motor Areas Contributes to Object Recognition.

    PubMed

    Sim, Eun-Jin; Helbig, Hannah B; Graf, Markus; Kiefer, Markus

    2015-09-01

    Recent evidence suggests an interaction between the ventral visual-perceptual and dorsal visuo-motor brain systems during the course of object recognition. However, the precise function of the dorsal stream for perception remains to be determined. The present study specified the functional contribution of the visuo-motor system to visual object recognition using functional magnetic resonance imaging and event-related potential (ERP) during action priming. Primes were movies showing hands performing an action with an object with the object being erased, followed by a manipulable target object, which either afforded a similar or a dissimilar action (congruent vs. incongruent condition). Participants had to recognize the target object within a picture-word matching task. Priming-related reductions of brain activity were found in frontal and parietal visuo-motor areas as well as in ventral regions including inferior and anterior temporal areas. Effective connectivity analyses suggested functional influences of parietal areas on anterior temporal areas. ERPs revealed priming-related source activity in visuo-motor regions at about 120 ms and later activity in the ventral stream at about 380 ms. Hence, rapidly initiated visuo-motor processes within the dorsal stream functionally contribute to visual object recognition in interaction with ventral stream processes dedicated to visual analysis and semantic integration.

  6. SU-E-T-557: Measuring Neutron Activation of Cardiac Devices Irradiated During Proton Therapy Using Indium Foils

    SciTech Connect

    Avery, S; Christodouleas, J; Delaney, K; Diffenderfer, E; Brown, K

    2014-06-01

    Purpose: Measuring Neutron Activation of Cardiac devices Irradiated during Proton Therapy using Indium Foils Methods: The foils had dimensions of 25mm x 25mm x 1mm. After being activated, the foils were placed in a Canberra Industries well chamber utilizing a NaI(Tl) scintillation detector. The resulting gamma spectrum was acquired and analyzed using Genie 2000 spectroscopy software. One activation foil was placed over the upper, left chest of RANDO where a pacemaker would be. The rest of the foils were placed over the midline of the patient at different distances, providing a spatial distribution over the phantom. Using lasers and BBs to align the patient, 200 MU square fields were delivered to various treatment sites: the brain, the pancreas, and the prostate. Each field was shot at least a day apart, giving more than enough time for activity of the foil to decay (t1=2 = 54.12 min). Results: The net counts (minus background) of the three aforementioned peaks were used for our measurements. These counts were adjusted to account for detector efficiency, relative photon yields from decay, and the natural abundance of 115-In. The average neutron flux for the closed multi-leaf collimator irradiation was measured to be 1.62 x 106 - 0.18 x 106 cm2 s-1. An order of magnitude estimate of the flux for neutrons up to 1 keV from Diffenderfer et al. gives 3 x 106 cm2 s-1 which does agree on the order of magnitude. Conclusion: Lower energy neutrons have higher interaction cross-sections and are more likely to damage pacemakers. The thermal/slow neutron component may be enough to estimate the overall risk. The true test of the applicability of activation foils is whether or not measurements are capable of predicting cardiac device malfunction. For that, additional studies are needed to provide clinical evidence one way or the other.

  7. Site-specific characterization of Castromil Brownfield area related to gold mining activities.

    PubMed

    Ferreira da Silva, Eduardo; Serrano Pinto, Luís; Patinha, Carla; Cardoso Fonseca, Edmundo

    2004-03-01

    Castromil is one of the gold mining areas in Portugal that has been abandoned since 1940. This area, which was first mined in Roman times, is located within a Hercynian granite body near the contact with Silurian metasediments. Gold is essentially disseminated along veins in the silicified granite, running NW-SE, related with a shear zone and frequently associated with sulphides (arsenopyrite and basically pyrite). In paragenetic terms, three stages of mineralization are considered: ferro-arseniferous (quartz + arsenopyrite I + pyrite I + pyrrhotite + bismuth), zinciferous (sphalerite + chalcopyrite), and remobilization (arsenopyrite II + galena + gold). Due to the lack of laws and environmental education, Castromil is today a gold mining heritage site where we can detect the consequences of an incautious exploration (tailings, wells and adits located in the old explored zone) and where a residential area is located. In order to characterize the actual state of the old mining area the trace metal contamination of soils and waters by mining activities was investigated. In the studied area 106 soil samples, 15 waters and 20 plants were sampled and analysed. The soil samples were analysed for 32 elements by ICP-AES. Waters were analysed by ionic chromatography and ICP-MS for major and trace elements. Plants were analysed for As, Fe and Pb by AAS. The results are discussed taking into account the risk-based standards for soils and groundwater's (target and intervention values) proposed by Swartjes (1999). The results show elevated concentration of As and Pb which were found in soils collected from agricultural areas. Foodstuff plants species collected in the Castromil agricultural area show high concentrations of As in the leaves (cabbage and lettuce) and in the tubers (potatoes). Groundwaters in the mining area contain high concentrations of As that exceeds the intervention values. The area must to be subject to a remediation process, considering the actual risks to

  8. MELANOPHORE BANDS AND AREAS DUE TO NERVE CUTTING, IN RELATION TO THE PROTRACTED ACTIVITY OF NERVES

    PubMed Central

    Parker, G. H.

    1941-01-01

    1. When appropriate chromatic nerves are cut caudal bands, cephalic areas, and the pelvic fins of the catfish Ameiurus darken. In pale fishes all these areas will sooner or later blanch. By recutting their nerves all such blanched areas will darken again. 2. These observations show that the darkening of caudal bands, areas, and fins on cutting their nerves is not due to paralysis (Brücke), to the obstruction of central influences such as inhibition (Zoond and Eyre), nor to vasomotor disturbances (Hogben), but to activities emanating from the cut itself. 3. The chief agents concerned with the color changes in Ameiurus are three: intermedin from the pituitary gland, acetylcholine from the dispersing nerves (cholinergic fibers), and adrenalin from the concentrating nerves (adrenergic fibers). The first two darken the fish; the third blanches it. In darkening the dispersing nerves appear to initiate the process and to be followed and substantially supplemented by intermedin. 4. Caudal bands blanch by lateral invasion, cephalic areas by lateral invasion and internal disintegration, and pelvic fins by a uniform process of general loss of tint equivalent to internal disintegration. 5. Adrenalin may be carried in such an oil as olive oil and may therefore act as a lipohumor; it is soluble in water and hence may act as a hydrohumor. In lateral invasion (caudal bands, cephalic areas) it probably acts as a lipohumor and in internal disintegration (cephalic areas, pelvic fins) it probably plays the part of a hydrohumor. 6. The duration of the activity of dispersing nerves after they had been cut was tested by means of the oscillograph, by anesthetizing blocks, and by cold-blocks. The nerves of Ameiurus proved to be unsatisfactory for oscillograph tests. An anesthetizing block, magnesium sulfate, is only partly satisfactory. A cold-block, 0°C., is successful to a limited degree. 7. By means of a cold-block it can be shown that dispersing autonomic nerve fibers in Ameiurus can

  9. Cometary activity, active areas, and a mechanism for collimated outflows on 1P, 9P, 19P, and 81P

    NASA Astrophysics Data System (ADS)

    Belton, Michael J. S.

    2010-12-01

    The properties of 50 jet and jet-filament outflows from 27 active areas observed on the four comet nuclei that have been visited by spacecraft (1P/Halley, 19P/Borrelly, 81P/Wild 2, and 9P/Tempel 1) are investigated and we propose a taxonomic categorization in which there are three types of active areas: Type I that is dominated by the sublimation of H 2O through the porous mantle; Type II that is controlled by the localized and persistent effusion of super-volatiles from the interior; and Type III that is characterized by episodic releases of super-volatiles. The zonally averaged distribution of active area locations associated with Type II outflows over the four comets is calculated and we find that they are distributed randomly in latitude. In longitude, the distribution shows a marginal tendency for active areas to occur more frequently in the region near the ends of the long axis or, alternatively, a tendency to avoid the region close to the ends of the intermediate axis. Combining observations of filamentary structure with exploratory hydrodynamic calculations we find that Type II outflows are likely to be relatively cold laminar flows (Re < 1000) of a mixture of CO 2, CO and H 2O that are highly collimated (6-10° full-cone angle) during the daytime as a result of being constrained by the ambient H 2O atmosphere. We propose that they become visible as a result of the turbulent momentum flux at the base of the filamentary structure that causes the friable surface to release dust at a higher rate than in surrounding areas. We present evidence that indicates that geophysical flows occur on cometary nuclei other than 9P/Tempel 1 and discuss a possible scenario for the long-term evolution of cometary surfaces near the Sun. We conclude with an exposition of a cometary activity paradigm brought up-to-date with discoveries made with recent space missions, associated Earth-based investigations, and the results of this work.

  10. Effects of Active and Passive Hearing Protection Devices on Sound Source Localization, Speech Recognition, and Tone Detection

    PubMed Central

    Brown, Andrew D.; Beemer, Brianne T.; Greene, Nathaniel T.; Argo, Theodore; Meegan, G. Douglas; Tollin, Daniel J.

    2015-01-01

    Hearing protection devices (HPDs) such as earplugs offer to mitigate noise exposure and reduce the incidence of hearing loss among persons frequently exposed to intense sound. However, distortions of spatial acoustic information and reduced audibility of low-intensity sounds caused by many existing HPDs can make their use untenable in high-risk (e.g., military or law enforcement) environments where auditory situational awareness is imperative. Here we assessed (1) sound source localization accuracy using a head-turning paradigm, (2) speech-in-noise recognition using a modified version of the QuickSIN test, and (3) tone detection thresholds using a two-alternative forced-choice task. Subjects were 10 young normal-hearing males. Four different HPDs were tested (two active, two passive), including two new and previously untested devices. Relative to unoccluded (control) performance, all tested HPDs significantly degraded performance across tasks, although one active HPD slightly improved high-frequency tone detection thresholds and did not degrade speech recognition. Behavioral data were examined with respect to head-related transfer functions measured using a binaural manikin with and without tested HPDs in place. Data reinforce previous reports that HPDs significantly compromise a variety of auditory perceptual facilities, particularly sound localization due to distortions of high-frequency spectral cues that are important for the avoidance of front-back confusions. PMID:26313145

  11. 77 FR 8260 - Agency Information Collection Activities; Proposed Collection; Comment Request; Medical Device...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... HUMAN SERVICES Food and Drug Administration Agency Information Collection Activities; Proposed... Reporting AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug... (HFA- 305), Food and Drug Administration, 5630 Fishers Lane, rm. 1061, Rockville, MD 20852....

  12. Monitoring Animal Activity Rhythms in the Laboratory: Four Easily Assembled Devices.

    ERIC Educational Resources Information Center

    Merritt, Sheridan V.

    1989-01-01

    The use of actographs for studying animal activity is discussed. Described are running recorders for rodents, perching and feeding recorders for birds, and tilting box recorders for studying the movement of reptiles, amphibians, and arthropods. (CW)

  13. New methodology to assess activity status of occlusal caries in primary teeth using laser fluorescence device

    NASA Astrophysics Data System (ADS)

    Braga, Mariana Minatel; Saveriano de Benedetto, Monique; Imparato, Jose Carlos Pettorossi; Mendes, Fausto Medeiros

    2010-07-01

    An in vivo study was conducted to verify the ability of laser fluorescence (LF) to assess the activity status of occlusal caries in primary teeth, using different air-drying times. Occlusal sites (707) were examined using LF (DIAGNOdent) after air-drying for 3 s and 15 s, and the difference between readings (DIF15 s-3 s) was calculated. For concurrent validation of LF, visual criteria-Nyvad (NY) and Lesion Activity Assessment associated with the International Caries Detection and Assessment System (LAA-ICDAS)-were the reference standards for lesion activity. Histological exam using a pH-indicator dye (0.1% methyl red) was performed in 46 exfoliated/extracted teeth for criterion validation. LF readings and DIF15 s-3 s were compared using Kruskall-Wallis and Mann-Whitney tests. Receiver operating characteristic analyses were performed and validity parameters calculated, considering the caries activity assessment. Using NY, active lesions (3 s: 30.0+/-29.3 15 s: 34.2+/-30.6) presented higher LF readings than inactive lesions (3 s: 17.0+/-16.3 15 s: 19.2+/-17.3 p<0.05), different from LAA-ICDAS. Active cavitated caries resulted in higher LF readings (3 s: 50.3+/-3.5 15 s: 54.7+/-30.2) than inactive cavitated caries (3 s: 19.9+/-16.3 15 s: 22.8+/-16.8). Therefore, LF can distinguish cavitated active and inactive lesions classified by NY, but not by LAA-ICDAS; however, this difference might be related to the visual system rather than to LF. The air-drying time could be an alternative to improve the caries activity assessment; however, longer air-drying time is suggested to be tested subsequently.

  14. New methodology to assess activity status of occlusal caries in primary teeth using laser fluorescence device.

    PubMed

    Braga, Mariana Minatel; de Benedetto, Monique Saveriano; Imparato, Jose Carlos Pettorossi; Mendes, Fausto Medeiros

    2010-01-01

    An in vivo study was conducted to verify the ability of laser fluorescence (LF) to assess the activity status of occlusal caries in primary teeth, using different air-drying times. Occlusal sites (707) were examined using LF (DIAGNOdent) after air-drying for 3 s and 15 s, and the difference between readings (DIF15 s-3 s) was calculated. For concurrent validation of LF, visual criteria-Nyvad (NY) and Lesion Activity Assessment associated with the International Caries Detection and Assessment System (LAA-ICDAS)-were the reference standards for lesion activity. Histological exam using a pH-indicator dye (0.1% methyl red) was performed in 46 exfoliated/extracted teeth for criterion validation. LF readings and DIF15 s-3 s were compared using Kruskall-Wallis and Mann-Whitney tests. Receiver operating characteristic analyses were performed and validity parameters calculated, considering the caries activity assessment. Using NY, active lesions (3 s: 30.0+/-29.3; 15 s: 34.2+/-30.6) presented higher LF readings than inactive lesions (3 s: 17.0+/-16.3; 15 s: 19.2+/-17.3; p<0.05), different from LAA-ICDAS. Active cavitated caries resulted in higher LF readings (3 s: 50.3+/-3.5; 15 s: 54.7+/-30.2) than inactive cavitated caries (3 s: 19.9+/-16.3; 15 s: 22.8+/-16.8). Therefore, LF can distinguish cavitated active and inactive lesions classified by NY, but not by LAA-ICDAS; however, this difference might be related to the visual system rather than to LF. The air-drying time could be an alternative to improve the caries activity assessment; however, longer air-drying time is suggested to be tested subsequently.

  15. Underwater Sound Levels at a Wave Energy Device Testing Facility in Falmouth Bay, UK.

    PubMed

    Garrett, Joanne K; Witt, Matthew J; Johanning, Lars

    2016-01-01

    Passive acoustic monitoring devices were deployed at FaBTest in Falmouth Bay, UK, a marine renewable energy device testing facility during trials of a wave energy device. The area supports considerable commercial shipping and recreational boating along with diverse marine fauna. Noise monitoring occurred during (1) a baseline period, (2) installation activity, (3) the device in situ with inactive power status, and (4) the device in situ with active power status. This paper discusses the preliminary findings of the sound recording at FabTest during these different activity periods of a wave energy device trial.

  16. Complex-envelope alternating-direction-implicit FDTD method for simulating active photonic devices with semiconductor/solid-state media.

    PubMed

    Singh, Gurpreet; Ravi, Koustuban; Wang, Qian; Ho, Seng-Tiong

    2012-06-15

    A complex-envelope (CE) alternating-direction-implicit (ADI) finite-difference time-domain (FDTD) approach to treat light-matter interaction self-consistently with electromagnetic field evolution for efficient simulations of active photonic devices is presented for the first time (to our best knowledge). The active medium (AM) is modeled using an efficient multilevel system of carrier rate equations to yield the correct carrier distributions, suitable for modeling semiconductor/solid-state media accurately. To include the AM in the CE-ADI-FDTD method, a first-order differential system involving CE fields in the AM is first set up. The system matrix that includes AM parameters is then split into two time-dependent submatrices that are then used in an efficient ADI splitting formula. The proposed CE-ADI-FDTD approach with AM takes 22% of the time as the approach of the corresponding explicit FDTD, as validated by semiconductor microdisk laser simulations.

  17. Enhanced Performance of Organic Thin Film Transistor Devices Using Hydroxyethyl-Terminated P3HT as the Active Layer.

    PubMed

    Yeh, Je-Yuan; Tsiang, Raymond Chien-Chao

    2015-05-01

    Hydroxyethyl-terminated poly(3-hexylthiophene) (P3HT-OH) have been synthesized via a catalyst-transfer polycondensation using Grignard metathesis mediated by a nickel-based catalyst. This hydrophilic P3HT-OH is compared against the hydrophobic P3HT when used as an active layer on silicon dioxide (SiO2) wafer for organic thin-film-transistor (OTFT) fabrication. Hydroxyl groups at a 7.5% weight content lead to more chain regularity when polymer is bonded to SiO2 wafer surface and thus enhance the performance of OTFT Device, such as an 114.2% increase in ON/OFF ratio, an 12.4% increase in mobility, a 23.3% decrease in threshold voltage and a 30.1% decrease in surface roughness. Analysis and measurements reported in this paper have illustrated for the first time the feasibility of imparting hydrophilicity to the active layer for improving the OTFT performance.

  18. Active Flash: Performance-Energy Tradeoffs for Out-of-Core Processing on Non-Volatile Memory Devices

    SciTech Connect

    Boboila, Simona; Kim, Youngjae; Vazhkudai, Sudharshan S; Desnoyers, Peter; Shipman, Galen M

    2012-01-01

    In this abstract, we study the performance and energy tradeoffs involved in migrating data analysis into the flash device, a process we refer to as Active Flash. The Active Flash paradigm is similar to 'active disks', which has received considerable attention. Active Flash allows us to move processing closer to data, thereby minimizing data movement costs and reducing power consumption. It enables true out-of-core computation. The conventional definition of out-of-core solvers refers to an approach to process data that is too large to fit in the main memory and, consequently, requires access to disk. However, in Active Flash, processing outside the host CPU literally frees the core and achieves real 'out-of-core' analysis. Moving analysis to data has long been desirable, not just at this level, but at all levels of the system hierarchy. However, this requires a detailed study on the tradeoffs involved in achieving analysis turnaround under an acceptable energy envelope. To this end, we first need to evaluate if there is enough computing power on the flash device to warrant such an exploration. Flash processors require decent computing power to run the internal logic pertaining to the Flash Translation Layer (FTL), which is responsible for operations such as address translation, garbage collection (GC) and wear-leveling. Modern SSDs are composed of multiple packages and several flash chips within a package. The packages are connected using multiple I/O channels to offer high I/O bandwidth. SSD computing power is also expected to be high enough to exploit such inherent internal parallelism within the drive to increase the bandwidth and to handle fast I/O requests. More recently, SSD devices are being equipped with powerful processing units and are even embedded with multicore CPUs (e.g. ARM Cortex-A9 embedded processor is advertised to reach 2GHz frequency and deliver 5000 DMIPS; OCZ RevoDrive X2 SSD has 4 SandForce controllers, each with 780MHz max frequency

  19. Encapsulation of single cells on a microfluidic device integrating droplet generation with fluorescence-activated droplet sorting.

    PubMed

    Wu, Liang; Chen, Pu; Dong, Yingsong; Feng, Xiaojun; Liu, Bi-Feng

    2013-06-01

    Encapsulation of single cells is a challenging task in droplet microfluidics due to the random compartmentalization of cells dictated by Poisson statistics. In this paper, a microfluidic device was developed to improve the single-cell encapsulation rate by integrating droplet generation with fluorescence-activated droplet sorting. After cells were loaded into aqueous droplets by hydrodynamic focusing, an on-flight fluorescence-activated sorting process was conducted to isolate droplets containing one cell. Encapsulation of fluorescent polystyrene beads was investigated to evaluate the developed method. A single-bead encapsulation rate of more than 98 % was achieved under the optimized conditions. Application to encapsulate single HeLa cells was further demonstrated with a single-cell encapsulation rate of 94.1 %, which is about 200 % higher than those obtained by random compartmentalization. We expect this new method to provide a useful platform for encapsulating single cells, facilitating the development of high-throughput cell-based assays.

  20. Active Feedback Control of a Web Flutter Using Flow Control Devices

    NASA Astrophysics Data System (ADS)

    Hayashi, Yusuke; Watanabe, Masahiro; Hara, Kensuke

    This paper develops a non-contact active feedback control of web flutter in a narrow passage by using movable plates set at inlet and outlet of the passage. The strategy of this active feedback control is based on the flow-control which cancels the exciting fluid force acting on the web, i.e., cancels the self-excited feedback mechanism. In this paper, suppression of the web flutter by the active feedback control is demonstrated experimentally. In the experiments, a web (film), as a controlled object, is subjected to air flow in a narrow passage. The web flutter occurs to the web in the translational motion over the critical flow velocity. And the web flutter is actively controlled and suppressed by the movable plate motion which changes the air flow in the passage. The critical flow velocity under controlled condition is examined with changing the controller gain and phase-shift between the web motion and the movable plate motion. As a result, it is indicated that the active feedback control increases the critical flow velocity, and suppress the web flutter effectively. Moreover, the control performance is examined experimentally, and stabilization mechanism by the active feedback control is discussed.

  1. Social safety, self-rated general health and physical activity: changes in area crime, area safety feelings and the role of social cohesion.

    PubMed

    Ruijsbroek, Annemarie; Droomers, Mariël; Groenewegen, Peter P; Hardyns, Wim; Stronks, Karien

    2015-01-01

    The aim of this study was to examine whether changes over time in reported area crime and perceived area safety were related to self-rated general health and physical activity (PA), in order to provide support for a causal relationship between social safety and health. Additionally, we investigated whether social cohesion protects the residents against the negative impact of unsafe areas on health and PA. Multilevel logistic regression analyses were performed on Dutch survey data, including 47,926 respondents living in 2974 areas. An increase in area level unsafety feelings between 2009 and 2011 was associated with more people reporting poor general health in 2012 in that area, but was not related to PA. Changes in reported area crime were not related to either poor general health or PA. The social cohesion in the area did not modify the effect of changes in social safety on health and PA. The results suggest that tackling feelings of unsafety in an area might contribute to the better general health of the residents. Because changes in area social safety were not associated with PA, we found no leads that such health benefits were achieved through an increase in physical activity.

  2. Design of a computer game using an eye-tracking device for eye's activity rehabilitation

    NASA Astrophysics Data System (ADS)

    Lin, Chern-Sheng; Huan, Chia-Chin; Chan, Chao-Ning; Yeh, Mau-Shiun; Chiu, Chuang-Chien

    2004-07-01

    An eye mouse interface that can be used to operate a computer using the movement of the eyes is described. We developed this eye-tracking system for eye motion disability rehabilitation. When the user watches the screen of a computer, a charge-coupled device will catch images of the user's eye and transmit it to the computer. A program, based on a new cross-line tracking and stabilizing algorithm, will locate the center point of the pupil in the images. The calibration factors and energy factors are designed for coordinate mapping and blink functions. After the system transfers the coordinates of pupil center in the images to the display coordinate, it will determine the point at which the user gazed on the display, then transfer that location to the game subroutine program. We used this eye-tracking system as a joystick to play a game with an application program in a multimedia environment. The experimental results verify the feasibility and validity of this eye-game system and the rehabilitation effects for the user's visual movement.

  3. A multimodal optical and electrochemical device for monitoring surface reactions: redox active surfaces in porous silicon Rugate filters.

    PubMed

    Ciampi, Simone; Guan, Bin; Darwish, Nadim A; Zhu, Ying; Reece, Peter J; Gooding, J Justin

    2012-12-21

    Herein, mesoporous silicon (PSi) is configured as a single sensing device that has dual readouts; as a photonic crystal sensor in a Rugate filter configuration, and as a high surface area porous electrode. The as-prepared PSi is chemically modified to provide it with stability in aqueous media and to allow for the subsequent coupling of chemical species, such as via Cu(I)-catalyzed cycloaddition reactions between 1-alkynes and azides ("click" reactions). The utility of the bimodal capabilities of the PSi sensor for monitoring surface coupling procedures is demonstrated by the covalent coupling of a ferrocene derivative, as well as by demonstrating ligand-exchange reactions (LER) at the PSi surface. Both types of reactions were monitored through optical reflectivity measurements, as well as electrochemically via the oxidation/reduction of the surface tethered redox species.

  4. Evaluation of antimicrobial activity of Malus domestica fruit extract from Kashan area

    PubMed Central

    Jelodarian, Sara; Haghir Ebrahimabadi, Abdolrasoul; Jookar Kashi, Fereshteh

    2013-01-01

    Objective: Many species of plants present noticeable potency against human bacterial and fungal pathogens. Materials and Methods: In the current study, antimicrobial activity of the fresh fruits of 4 cultivars (A to D) of Malus domestica cultivated in the Qamsar area of Kashan, Iran was investigated. The disk diffusion and minimal inhibitory concentration (MIC) evaluation antimicrobial activity tests were performed. Results: The samples showed moderate antimicrobial activities with inhibition zones from 11 to 16 mm in these tests. Cultivar D with inhibition zones of 16, 14, and 12 mm for E. coli, S. epidermidis and K. pneumoniae, respectively exhibited the best results in these tests. Cultivar A also showed a zone of inhibition of 11 mm against P. aerouginosa. Conclusion: Moderate antimicrobial activities were observed for the studied apple cultivars. PMID:25050254

  5. Epileptiform activity in the mouse visual cortex interferes with cortical processing in connected areas

    PubMed Central

    Petrucco, L.; Pracucci, E.; Brondi, M.; Ratto, G. M.; Landi, S.

    2017-01-01

    Epileptiform activity is associated with impairment of brain function even in absence of seizures, as demonstrated by failures in various testing paradigm in presence of hypersynchronous interictal spikes (ISs). Clinical evidence suggests that cognitive deficits might be directly caused by the anomalous activity rather than by its underlying etiology. Indeed, we seek to understand whether ISs interfere with neuronal processing in connected areas not directly participating in the hypersynchronous activity in an acute model of epilepsy. Here we cause focal ISs in the visual cortex of anesthetized mice and we determine that, even if ISs do not invade the opposite hemisphere, the local field potential is subtly disrupted with a modulation of firing probability imposed by the contralateral IS activity. Finally, we find that visual processing is altered depending on the temporal relationship between ISs and stimulus presentation. We conclude that focal ISs interact with normal cortical dynamics far from the epileptic focus, disrupting endogenous oscillatory rhythms and affecting information processing. PMID:28071688

  6. The analysis of interseismic GPS observation and its implication to seismic activity in Taiwan area

    NASA Astrophysics Data System (ADS)

    Tsai, M. C.; Yu, S. B.; Shin, T. C.

    2015-12-01

    Taiwan is an active tectonic area with about 80 mm/yr plate convergence rate. To understand the crustal deformation and seismic potential in Taiwan area. We derived 2009-2014 interseismic GPS velocity field and strain rate, implicate to seismic activity of 2005-2014. Data collected by 281 sites of Taiwan Continuous GPS (cGPS) Array and processed with GAMIT/GLOBK software. Stacking of power spectral densities from cGPS data in Taiwan, we found the errors type can be described as a combination of white noise and flicker noise. The common errors are removed by stacking 50 cGPS sites with data period larger than 5 years. By removing the common errors, the precision of GPS data has been further improved to 2.3 mm, 1.9 mm, and 6.9 mm in the E, N, U components, respectively. After strictly data quality control, time series analysis and noise analysis, we derive an interseismic ITRF2008 velocity field from 2009 to 2014 in the Taiwan area. The general pattern is quite similar with previous studies, but the station density is much larger and spatial coverage better. Based on this interseismic velocity field, we estimate the crustal strain rate in Taiwan area. Approximately half of plate convergence strain rate is accommodated on the fold and thrust belt of western Taiwan and another half is taken up in the Longitudinal Valley and the Coastal Range in eastern Taiwan. The maximum dilatation rates is about -0.75~-0.9 μstrain/yr in WNW-ESE direction. The velocities in western Taiwan generally show a fan-shaped pattern, consistent with the direction of maximum compression tectonic stress. Extension in the E-W direction is observed at the Central Range area, the focal mechanism results also indicate the earthquake type here most are normal faults. In northern Taiwan, the velocity vectors reveal clockwise rotation, indicating the on-going extensional deformation related to the back-arc extension of the Okinawa Trough. In southern Taiwan, the horizontal velocity increases from

  7. Increasing Hydrogen Ion Activity of Water in Two Reservoirs Supplying the San Francisco Bay Area, California

    NASA Astrophysics Data System (ADS)

    McColl, J. G.

    1981-10-01

    The hydrogen ion activity (H+) of water in two Sierra Nevada reservoirs (Pardee and Hetch Hetchy) that supply the San Francisco Bay area has been increasing with time over the period 1954-1979. This conclusion is based on weekly measurements ofpH at the two reservoirs and is supported by measurements of alkalinity which decreased at Pardee over the period 1944-1979. Based on linear models, the rate of the increasing (H+) was the same at both reservoirs, and (H+) varied concomitantly from year to year, suggesting a common, general cause. Mean monthly variation in (H+) corresponded to mean monthly variation in atmospheric pollution from a nine-county area around San Francisco Bay. The most likely cause of the increasing (H+) of reservoir waters is NOx from automobile exhausts primarily from the San Francisco Bay area.

  8. Mesopore control of high surface area NaOH-activated carbon.

    PubMed

    Tseng, Ru-Ling

    2006-11-15

    Activated carbon with BET surface areas in a narrow range from 2318 to 2474 m2/g was made by soaking the char made from corncob in a concentrated NaOH solution at NaOH/char ratios from 3 to 6; the mesopore volumes of the activated carbon were significantly changed from 21 to 58%. The relationships between pore properties (Sp, Vpore, Vmicro/Vpore, Dp) and NaOH dosage were investigated. Comparisons between the methods of NaOH and KOH activation revealed that NaOH activation can suitably control the mesopore specific volume of the activated carbon. Elemental analysis revealed that the H/C and O/C values of the activated carbons of NaOH/char ratios from 3 to 6 were significantly lower. SEM observation of surface hole variation of the activated carbon ascertained that the reaction process was inner pore etching. Based on the above three measurements and experimental investigations, the assumption made by previous researchers, namely that NaOH and KOH produce similar results, was challenged. Furthermore, the adsorption kinetics was used to investigate the adsorption rate of an Elovich equation to determine the relationships between the adsorption behavior on larger molecules (dyes) and smaller molecules (phenols) and the pore structure of the activated carbon.

  9. [Experience of DMAT rescue activity by doctor-helicopter in Tohoku Area after the earthquake].

    PubMed

    Otsuka, Naomi; Yamashita, Ako; Kimura, Yoshinobu; Aimono, Mako; Kobayashi, Iwao; Nanba, Hitoshi; Watanabe, Akihiko; Sumita, Shinzou

    2012-07-01

    We operated rescue activities in Tohoku area after the earthquake of March 11th, 2011. From our hospital, a doctor-helicopter flew to the staging care unit at Hanamaki airport with two members of the disaster medical assistance team (DMAT), one of whom was an anesthesiologist. The helicopter carried ten patients by nine flight missions, who were the victims of tsunami after the earthquake. There were seven doctor-helicopters from all over Japan and did the missions based at Hanamaki airport. The missions was quite different from our usual job as an anesthesiologist, but we could transfer the patients safely by using some knowledge of stabilizing the unstable patients as flight doctors. We report the details of our activities by our doctor-helicopters in Tohoku area.

  10. Activated barrier for protection of special nuclear materials in vital areas

    SciTech Connect

    Timm, R.E.; Miranda, J.E.; Reigle, D.L.; Valente, A.D.

    1984-07-15

    The Argonne National Laboratory and Sandia National Laboratory have recently installed an activated barrier, the Access Denial System (ADS) for the upgrade of safeguards of special nuclear materials. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The installation was the first for the Department of Energy. Subsequently, two additional installations have been completed. The Access Denial System, combined with physical restraints, provide the system delay. The principal advantages of the activated barrier are: (1) it provides an order of magnitude improvement in delay over that of a fixed barrier, (2) it can be added to existing vital areas with a minimum of renovations, (3) existing operations are minimally impacted, and (4) health and safety risks are virtually nonexistent. Hardening of the vital areas using the ADS was accomplished in a cost-effective manner. 3 references, 1 figure, 1 table.

  11. Preliminary results of systematic sampling of gas manifestations in geodynamically active areas of Greece

    NASA Astrophysics Data System (ADS)

    Daskalopoulou, Kyriaki; D'Alessandro, Walter; Calabrese, Sergio; Kyriakopoulos, Konstantinos

    2016-04-01

    Greece is located on a convergent plate boundary comprising the subduction of the African Plate beneath the Eurasian, while the Arabian plate approaches the Eurasian in a northwestward motion. It is considered to be one of the most tectonically active regions of Earth with a complex geodynamic setting, deriving from a long and complicated geological history. Due to this specific geological background, conditions for the formation of many thermal springs are favoured. In the past years, almost all the already known sites of degassing (fumaroles, soil gases, mofettes, gas bubbling in cold and thermal waters) located in the Hellenic area were sampled at least one time. Collected samples were analysed for their chemical (He, Ne, Ar, O2, N2, H2, H2S, CO, CH4 and CO2) and isotopic composition (He, C and N). Some of these sites have been selected for systematic sampling. Four of them have records longer than 10 years with tens of samplings also considering some literature data. Two of the sites are located in active volcanic areas (Santorini and Nisyros) while the other two are close to actively spreading graben structures with intense seismic activity (Gulf of Korinth and Sperchios basin). Results allowed to define long term background values and also some interesting variation related to seismic or volcanic activity.

  12. From Data Acquisition to Data Fusion: A Comprehensive Review and a Roadmap for the Identification of Activities of Daily Living Using Mobile Devices.

    PubMed

    Pires, Ivan Miguel; Garcia, Nuno M; Pombo, Nuno; Flórez-Revuelta, Francisco

    2016-02-02

    This paper focuses on the research on the state of the art for sensor fusion techniques, applied to the sensors embedded in mobile devices, as a means to help identify the mobile device user's daily activities. Sensor data fusion techniques are used to consolidate the data collected from several sensors, increasing the reliability of the algorithms for the identification of the different activities. However, mobile devices have several constraints, e.g., low memory, low battery life and low processing power, and some data fusion techniques are not suited to this scenario. The main purpose of this paper is to present an overview of the state of the art to identify examples of sensor data fusion techniques that can be applied to the sensors available in mobile devices aiming to identify activities of daily living (ADLs).

  13. From Data Acquisition to Data Fusion: A Comprehensive Review and a Roadmap for the Identification of Activities of Daily Living Using Mobile Devices

    PubMed Central

    Pires, Ivan Miguel; Garcia, Nuno M.; Pombo, Nuno; Flórez-Revuelta, Francisco

    2016-01-01

    This paper focuses on the research on the state of the art for sensor fusion techniques, applied to the sensors embedded in mobile devices, as a means to help identify the mobile device user’s daily activities. Sensor data fusion techniques are used to consolidate the data collected from several sensors, increasing the reliability of the algorithms for the identification of the different activities. However, mobile devices have several constraints, e.g., low memory, low battery life and low processing power, and some data fusion techniques are not suited to this scenario. The main purpose of this paper is to present an overview of the state of the art to identify examples of sensor data fusion techniques that can be applied to the sensors available in mobile devices aiming to identify activities of daily living (ADLs). PMID:26848664

  14. Cleaning devices

    NASA Technical Reports Server (NTRS)

    Schneider, Horst W. (Inventor)

    1981-01-01

    Cleaning devices are described which include a vacuum cleaner nozzle with a sharp rim for directing incoming air down against the floor; a vacuum cleaner wherein electrostatically charged brushes that brush dirt off a floor, are electrically grounded to remove charges that could tend to hold dirt to the brushes; a vacuum cleaner head having slots that form a pair of counter-rotating vortices, and that includes an outlet that blows a stream of air at the floor region which lies between the vortices; a cleaning device that sweeps a group of brushes against the ground along a first direction, and then sweeps them along the same ground area but in a second direction angled from the first by an amount such as 90.degree., to sweep up particles lying in crevices extending along any direction; a device that gently cleans a surface to remove bacteria for analysis, including an inclined wall along which cleaning fluid flows onto the surface, a vacuum chamber for drawing in the cleaning fluid, and a dividing wall spaced slightly from the surface to separate the fluid source from the vacuum cleaner chamber; and a device for providing pulses of pressured air including a chamber to which pressured air is supplied, a ball that circulates around the chamber to repeatedly close an outlet, and an air source that directs air circumferentially to move the ball around the chamber.

  15. Hierarchically nanoporous ceria nanoparticles with a high-surface area: synthesis, characterization, and their catalytic activity.

    PubMed

    Ge, Jiechao; Zhong, Liangshu; Zhuo, Linhai; Tang, Bo; Song, Weiguo

    2011-01-01

    A redox route based on ethylene glycol mediated process was developed to synthesize hierarchically nanoporpous ceria nanoparticles (ceria HNPNPs). The synthesized ceria HNPNPs are composed of building blocks fabricated with cubic ceria nanocrystals of several nanometers in diameter. Scanning electron microscopy was performed to investigate the evolution process of ceria precursor, and a two-step growth process was suggested for the morphology evolution. The synthesized ceria HNPNPs exhibit high surface area, which lead to high catalytic activity for CO oxidation.

  16. Effect of particle surface area on ice active site densities retrieved from droplet freezing spectra

    NASA Astrophysics Data System (ADS)

    Beydoun, Hassan; Polen, Michael; Sullivan, Ryan C.

    2016-10-01

    Heterogeneous ice nucleation remains one of the outstanding problems in cloud physics and atmospheric science. Experimental challenges in properly simulating particle-induced freezing processes under atmospherically relevant conditions have largely contributed to the absence of a well-established parameterization of immersion freezing properties. Here, we formulate an ice active, surface-site-based stochastic model of heterogeneous freezing with the unique feature of invoking a continuum assumption on the ice nucleating activity (contact angle) of an aerosol particle's surface that requires no assumptions about the size or number of active sites. The result is a particle-specific property g that defines a distribution of local ice nucleation rates. Upon integration, this yields a full freezing probability function for an ice nucleating particle. Current cold plate droplet freezing measurements provide a valuable and inexpensive resource for studying the freezing properties of many atmospheric aerosol systems. We apply our g framework to explain the observed dependence of the freezing temperature of droplets in a cold plate on the concentration of the particle species investigated. Normalizing to the total particle mass or surface area present to derive the commonly used ice nuclei active surface (INAS) density (ns) often cannot account for the effects of particle concentration, yet concentration is typically varied to span a wider measurable freezing temperature range. A method based on determining what is denoted an ice nucleating species' specific critical surface area is presented and explains the concentration dependence as a result of increasing the variability in ice nucleating active sites between droplets. By applying this method to experimental droplet freezing data from four different systems, we demonstrate its ability to interpret immersion freezing temperature spectra of droplets containing variable particle concentrations. It is shown that general

  17. Areas activated during naturalistic reading comprehension overlap topological visual, auditory, and somatotomotor maps

    PubMed Central

    2016-01-01

    Abstract Cortical mapping techniques using fMRI have been instrumental in identifying the boundaries of topological (neighbor‐preserving) maps in early sensory areas. The presence of topological maps beyond early sensory areas raises the possibility that they might play a significant role in other cognitive systems, and that topological mapping might help to delineate areas involved in higher cognitive processes. In this study, we combine surface‐based visual, auditory, and somatomotor mapping methods with a naturalistic reading comprehension task in the same group of subjects to provide a qualitative and quantitative assessment of the cortical overlap between sensory‐motor maps in all major sensory modalities, and reading processing regions. Our results suggest that cortical activation during naturalistic reading comprehension overlaps more extensively with topological sensory‐motor maps than has been heretofore appreciated. Reading activation in regions adjacent to occipital lobe and inferior parietal lobe almost completely overlaps visual maps, whereas a significant portion of frontal activation for reading in dorsolateral and ventral prefrontal cortex overlaps both visual and auditory maps. Even classical language regions in superior temporal cortex are partially overlapped by topological visual and auditory maps. By contrast, the main overlap with somatomotor maps is restricted to a small region on the anterior bank of the central sulcus near the border between the face and hand representations of M‐I. Hum Brain Mapp 37:2784–2810, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27061771

  18. Procedure for recording the simultaneous activity of single neurons distributed across cortical areas during sensory discrimination

    PubMed Central

    Hernández, Adrián; Nácher, Verónica; Luna, Rogelio; Alvarez, Manuel; Zainos, Antonio; Cordero, Silvia; Camarillo, Liliana; Vázquez, Yuriria; Lemus, Luis; Romo, Ranulfo

    2008-01-01

    We report a procedure for recording the simultaneous activity of single neurons distributed across five cortical areas in behaving monkeys. The procedure consists of a commercially available microdrive adapted to a commercially available neural data collection system. The critical advantage of this procedure is that, in each cortical area, a configuration of seven microelectrodes spaced 250–500 μm can be inserted transdurally and each can be moved independently in the z axis. For each microelectrode, the data collection system can record the activity of up to five neurons together with the local field potential (LFP). With this procedure, we normally monitor the simultaneous activity of 70–100 neurons while trained monkeys discriminate the difference in frequency between two vibrotactile stimuli. Approximately 20–60 of these neurons have response properties previously reported in this task. The neuronal recordings show good signal-to-noise ratio, are remarkably stable along a 1-day session, and allow testing several protocols. Microelectrodes are removed from the brain after a 1-day recording session, but are reinserted again the next day by using the same or different x-y microelectrode array configurations. The fact that microelectrodes can be moved in the z axis during the recording session and that the x-y configuration can be changed from day to day maximizes the probability of studying simultaneous interactions, both local and across distant cortical areas, between neurons associated with the different components of this task. PMID:18946031

  19. Areas activated during naturalistic reading comprehension overlap topological visual, auditory, and somatotomotor maps.

    PubMed

    Sood, Mariam R; Sereno, Martin I

    2016-08-01

    Cortical mapping techniques using fMRI have been instrumental in identifying the boundaries of topological (neighbor-preserving) maps in early sensory areas. The presence of topological maps beyond early sensory areas raises the possibility that they might play a significant role in other cognitive systems, and that topological mapping might help to delineate areas involved in higher cognitive processes. In this study, we combine surface-based visual, auditory, and somatomotor mapping methods with a naturalistic reading comprehension task in the same group of subjects to provide a qualitative and quantitative assessment of the cortical overlap between sensory-motor maps in all major sensory modalities, and reading processing regions. Our results suggest that cortical activation during naturalistic reading comprehension overlaps more extensively with topological sensory-motor maps than has been heretofore appreciated. Reading activation in regions adjacent to occipital lobe and inferior parietal lobe almost completely overlaps visual maps, whereas a significant portion of frontal activation for reading in dorsolateral and ventral prefrontal cortex overlaps both visual and auditory maps. Even classical language regions in superior temporal cortex are partially overlapped by topological visual and auditory maps. By contrast, the main overlap with somatomotor maps is restricted to a small region on the anterior bank of the central sulcus near the border between the face and hand representations of M-I. Hum Brain Mapp 37:2784-2810, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

  20. The Role of Mechanically Activated Area on Tribocorrosion of CoCrMo

    NASA Astrophysics Data System (ADS)

    Arenas, Maria Angeles; Conde, Ana; de Damborenea, Juan J.

    2013-09-01

    Co-Cr-Mo alloys are among the most used alloys for orthopedic implants because of their excellent corrosion resistance, mechanical properties, and biocompatibility. Although there is extensive literature on corrosion properties of Co-Cr-Mo alloys, fewer articles are focused on the synergistic effect of corrosion and wear in a simulated physiological solution. It is generally assumed that the current density measured during wear conditions for passive materials comes from the active area. However, there are no clear data supporting this statement. The current article correlates electrochemical measurements with the active area generated during sliding wear tests. Open circuit potential and current measurements, potentiodynamic scans, and electrochemical impedance spectroscopy were carried out on samples under static and sliding wear conditions. These measurements showed the importance of the active area, where the current coming from the surface not being abraded is negligible. Finally, by combining the sliding wear and electrochemical tests, the synergistic effect of wear and corrosion was characterized for this alloy, documenting the metal carbide's detachment from the cobalt alloy matrix, which leads to a significant increase of total wear volume.

  1. Are Currently Available Wearable Devices for Activity Tracking and Heart Rate Monitoring Accurate, Precise, and Medically Beneficial?

    PubMed Central

    El-Amrawy, Fatema

    2015-01-01

    Objectives The new wave of wireless technologies, fitness trackers, and body sensor devices can have great impact on healthcare systems and the quality of life. However, there have not been enough studies to prove the accuracy and precision of these trackers. The objective of this study was to evaluate the accuracy, precision, and overall performance of seventeen wearable devices currently available compared with direct observation of step counts and heart rate monitoring. Methods Each participant in this study used three accelerometers at a time, running the three corresponding applications of each tracker on an Android or iOS device simultaneously. Each participant was instructed to walk 200, 500, and 1,000 steps. Each set was repeated 40 times. Data was recorded after each trial, and the mean step count, standard deviation, accuracy, and precision were estimated for each tracker. Heart rate was measured by all trackers (if applicable), which support heart rate monitoring, and compared to a positive control, the Onyx Vantage 9590 professional clinical pulse oximeter. Results The accuracy of the tested products ranged between 79.8% and 99.1%, while the coefficient of variation (precision) ranged between 4% and 17.5%. MisFit Shine showed the highest accuracy and precision (along with Qualcomm Toq), while Samsung Gear 2 showed the lowest accuracy, and Jawbone UP showed the lowest precision. However, Xiaomi Mi band showed the best package compared to its price. Conclusions The accuracy and precision of the selected fitness trackers are reasonable and can indicate the average level of activity and thus average energy expenditure. PMID:26618039

  2. Bat mortality and activity at a Northern Iowa wind resource area

    USGS Publications Warehouse

    Jain, A.A.; Koford, Rolf R.; Hancock, A.W.; Zenner, G.G.

    2011-01-01

    We examined bat collision mortality, activity and species composition at an 89-turbine wind resource area in farmland of north-central Iowa from mid-Apr. to mid-Dec., 2003 and mid-Mar. to mid-Dec., 2004. We found 30 bats beneath turbines on cleared ground and gravel access areas in 2003 and 45 bats in 2004. After adjusting for search probability, search efficiency and scavenging rate, we estimated total bat mortality at 396 ?? 72 (95 ci) in 2003 and 636 ?? 112 (95 ci) in 2004. Although carcasses were mostly migratory tree bats, we found a considerable proportion of little brown bats (Myotis lucifugus). We recorded 1465 bat echolocation call files at turbine sites ( 34.88 call files/detector-night) and 1536 bat call files at adjacent non-turbine sites ( 36.57 call files/detector-night). Bat activity did not differ significantly between turbine and non-turbine sites. A large proportion of recorded call files were made by Myotis sp. but this may be because we detected activity at ground level only. There was no relationship between types of turbine lights and either collision mortality or echolocation activity. The highest levels of bat echolocation activity and collision mortality were recorded during Jul. and Aug. during the autumn dispersal and migration period. The fatality rates for bats in general and little brown bats in particular were higher at the Top of Iowa Wind Resource Area than at other, comparable studies in the region. Future efforts to study behavior of bats in flight around turbines as well as cumulative impact studies should not ignore non-tree dwelling bats, generally regarded as minimally affected. ?? 2011, American Midland Naturalist.

  3. Influence of vegetation spatial heterogeneity on soil enzyme activity in burned Mediterranean areas

    NASA Astrophysics Data System (ADS)

    Mayor, Á. G.; Goirán, S.; Bautista, S.

    2009-04-01

    Mediterranean ecosystems are commonly considered resilient to wildfires. However, depending on fire severity and recurrence, post-fire climatic conditions and plant community type, the recovery rate of the vegetation can greatly vary. Often, the post-fire vegetation cover remains low and sparsely distributed many years after the wildfire, which could have profound impacts on ecosystem functioning. In this work, we studied the influence of vegetation patchiness on soil enzyme activity (acid phosphatase, β-glucosidase and urease), at the patch and landscape scales, in degraded dry Mediterranean shrublands affected by wildfires. At the patch scale, we assessed the variation in soil enzyme between bare soils and vegetation patches. At the landscape scale, we studied the relationships between soil enzyme activity and various landscape metrics (total patch cover, average interpatch length, average patch width, and patch density). The study was conducted in 19 sites in the Valencia Region (eastern Spain), which had been affected by large wildfires in 1991. Site selection aimed at capturing a wide range of the variability of post-fire plant recovery rates in Mediterranean areas. The activities of the three enzymes were significantly higher in soils under the vegetation canopies than in adjacent bare areas, which we attributed to the effect of plants on the soil amount of both enzyme substrates and enzymes. The differences between bare and plant microsites were larger in the case of the acid phosphatase and less marked for urease. The activity of acid phosphatase was also higher under patches of resprouter species than under patches of seeder species, probably due to the faster post-fire recovery and older age of resprouter patches in fire-prone ecosystems. Soil enzyme activities of β-glucosidase and urease in both bare soils and vegetation patches showed no relationships with any of the landscape metrics analysed. However, the activity of acid phosphatase increased

  4. Active Travel by Built Environment and Lifecycle Stage: Case Study of Osaka Metropolitan Area.

    PubMed

    Waygood, E Owen D; Sun, Yilin; Letarte, Laurence

    2015-12-15

    Active travel can contribute to physical activity achieved over a day. Previous studies have examined active travel associated with trips in various western countries, but few studies have examined this question for the Asian context. Japan has high levels of cycling, walking and public transport, similar to The Netherlands. Most studies have focused either on children or on adults separately, however, having children in a household will change the travel needs and wants of that household. Thus, here a household lifecycle stage approach is applied. Further, unlike many previous studies, the active travel related to public transport is included. Lastly, further to examining whether the built environment has an influence on the accumulation of active travel minutes, a binary logistic regression examines the built environment's influence on the World Health Organization's recommendations of physical activity. The findings suggest that there is a clear distinction between the urbanized centers and the surrounding towns and unurbanized areas. Further, active travel related to public transport trips is larger than pure walking trips. Females and children are more likely to achieve the WHO recommendations. Finally, car ownership is a strong negative influence.

  5. Active Travel by Built Environment and Lifecycle Stage: Case Study of Osaka Metropolitan Area

    PubMed Central

    Waygood, E. Owen D.; Sun, Yilin; Letarte, Laurence

    2015-01-01

    Active travel can contribute to physical activity achieved over a day. Previous studies have examined active travel associated with trips in various western countries, but few studies have examined this question for the Asian context. Japan has high levels of cycling, walking and public transport, similar to The Netherlands. Most studies have focused either on children or on adults separately, however, having children in a household will change the travel needs and wants of that household. Thus, here a household lifecycle stage approach is applied. Further, unlike many previous studies, the active travel related to public transport is included. Lastly, further to examining whether the built environment has an influence on the accumulation of active travel minutes, a binary logistic regression examines the built environment’s influence on the World Health Organization’s recommendations of physical activity. The findings suggest that there is a clear distinction between the urbanized centers and the surrounding towns and unurbanized areas. Further, active travel related to public transport trips is larger than pure walking trips. Females and children are more likely to achieve the WHO recommendations. Finally, car ownership is a strong negative influence. PMID:26694429

  6. Smart phone: a popular device supports amylase activity assay in fisheries research.

    PubMed

    Thongprajukaew, Karun; Choodum, Aree; Sa-E, Barunee; Hayee, Ummah

    2014-11-15

    Colourimetric determinations of amylase activity were developed based on a standard dinitrosalicylic acid (DNS) staining method, using maltose as the analyte. Intensities and absorbances of red, green and blue (RGB) were obtained with iPhone imaging and Adobe Photoshop image analysis. Correlation of green and analyte concentrations was highly significant, and the accuracy of the developed method was excellent in analytical performance. The common iPhone has sufficient imaging ability for accurate quantification of maltose concentrations. Detection limits, sensitivity and linearity were comparable to a spectrophotometric method, but provided better inter-day precision. In quantifying amylase specific activity from a commercial source (P>0.02) and fish samples (P>0.05), differences compared with spectrophotometric measurements were not significant. We have demonstrated that iPhone imaging with image analysis in Adobe Photoshop has potential for field and laboratory studies of amylase.

  7. Coherent phonon optics in a chip with an electrically controlled active device.

    PubMed

    Poyser, Caroline L; Akimov, Andrey V; Campion, Richard P; Kent, Anthony J

    2015-02-05

    Phonon optics concerns operations with high-frequency acoustic waves in solid media in a similar way to how traditional optics operates with the light beams (i.e. photons). Phonon optics experiments with coherent terahertz and sub-terahertz phonons promise a revolution in various technical applications related to high-frequency acoustics, imaging, and heat transport. Previously, phonon optics used passive methods for manipulations with propagating phonon beams that did not enable their external control. Here we fabricate a phononic chip, which includes a generator of coherent monochromatic phonons with frequency 378 GHz, a sensitive coherent phonon detector, and an active layer: a doped semiconductor superlattice, with electrical contacts, inserted into the phonon propagation path. In the experiments, we demonstrate the modulation of the coherent phonon flux by an external electrical bias applied to the active layer. Phonon optics using external control broadens the spectrum of prospective applications of phononics on the nanometer scale.

  8. Coherent phonon optics in a chip with an electrically controlled active device

    PubMed Central

    Poyser, Caroline L.; Akimov, Andrey V.; Campion, Richard P.; Kent, Anthony J.

    2015-01-01

    Phonon optics concerns operations with high-frequency acoustic waves in solid media in a similar way to how traditional optics operates with the light beams (i.e. photons). Phonon optics experiments with coherent terahertz and sub-terahertz phonons promise a revolution in various technical applications related to high-frequency acoustics, imaging, and heat transport. Previously, phonon optics used passive methods for manipulations with propagating phonon beams that did not enable their external control. Here we fabricate a phononic chip, which includes a generator of coherent monochromatic phonons with frequency 378 GHz, a sensitive coherent phonon detector, and an active layer: a doped semiconductor superlattice, with electrical contacts, inserted into the phonon propagation path. In the experiments, we demonstrate the modulation of the coherent phonon flux by an external electrical bias applied to the active layer. Phonon optics using external control broadens the spectrum of prospective applications of phononics on the nanometer scale. PMID:25652241

  9. An Exploratory Simulator Study on the Use of Active Control Devices in Car Driving

    DTIC Science & Technology

    1992-05-04

    system to the driver and therefore concurrently serve as a proprioceptive -tactual display (RPihmann, 1981). The term "tactual" is used in the meaning of...displayed proprioceptive -tactual cues (see common coding approach in information processing, Prinz, 1990). The control loop for an active control...KlMckner & St6cker; 1990). In its present form the accelerator hardly pvrode- any systematic proprioceptive - tactual feedback to the driver abot.t the

  10. LOADING DEVICE

    DOEpatents

    Ohlinger, L.A.

    1958-10-01

    A device is presented for loading or charging bodies of fissionable material into a reactor. This device consists of a car, mounted on tracks, into which the fissionable materials may be placed at a remote area, transported to the reactor, and inserted without danger to the operating personnel. The car has mounted on it a heavily shielded magazine for holding a number of the radioactive bodies. The magazine is of a U-shaped configuration and is inclined to the horizontal plane, with a cap covering the elevated open end, and a remotely operated plunger at the lower, closed end. After the fissionable bodies are loaded in the magazine and transported to the reactor, the plunger inserts the body at the lower end of the magazine into the reactor, then is withdrawn, thereby allowing gravity to roll the remaining bodies into position for successive loading in a similar manner.

  11. [The influence of proficiency level of foreign language on the activation patterns of language areas].

    PubMed

    Bryll, Amira; Binder, Marek; Urbanik, Andrzej

    2013-01-01

    The of aim of the present study was the estimation of the influence of proficiency level of the second language on activation patterns of language areas. 30 volunteers participated in the experiment (15 females and 15 males) from 18 to 40 years of age. Mean age was 28 years. All participants were divided by linguist into two groups according to their proficiency level of the foreign language: high proficiency group (HP) and low proficiency group (LP). Block design method was used in the performed experiment. The experimental task was speech production in the form of sentences, the control tusk was silence. The experiment was performed using 1,5 T MR system. Functional data analysis was performed using SPM2 software (Wellcome Department of Cognitive Neurology, Great Britain). In low proficiency group (LP) stronger activation was found in right inferior frontal gyrus (pars tiangulris) incuding insula and in the left hemisphere on the border of supramarginal and superior temporal gyrus. In high proficiency group (HP) more activated in second language (L2) was the left inferior frontal gyrus (pars tiangulris), and a small part of left middle frontal gyrus. Proficiency level of the second language influences the pattern of activation of language areas.

  12. Geology is the Key to Explain Igneous Activity in the Mediterranean Area

    NASA Astrophysics Data System (ADS)

    Lustrino, M.

    2014-12-01

    Igneous activity in tectonically complex areas can be interpreted in many different ways, producing completely different petrogenetic models. Processes such as oceanic and continental subduction, lithospheric delamination, changes in subduction polarity, slab break-off and mantle plumes have all been advocated as causes for changes in plate boundaries and magma production, including rate and temporal distribution, in the circum-Mediterranean area. This region thus provides a natural laboratory to investigate a range of geodynamic and magmatic processes. Although many petrologic and tectonic models have been proposed, a number of highly controversial questions still remain. No consensus has yet been reached about the capacity of plate-tectonic processes to explain the origin and style of the magmatism. Similarly, there is still not consensus on the ability of geochemical and petrological arguments to reveal the geodynamic evolution of the area. The wide range of chemical and mineralogical magma compositions produced within and around the Mediterranean, from carbonatites to strongly silica-undersaturated silico-carbonatites and melilitites to strongly silica-oversaturated rhyolites, complicate models and usually require a large number of unconstrained assumptions. Can the calcalkaline-sodic alkaline transition be related to any common petrogenetic point? Is igneous activity plate-tectonic- (top-down) or deep-mantle-controlled (bottom-up)? Do the rare carbonatites and carbonate-rich igneous rocks derive from the deep mantle or a normal, CO2-bearing upper mantle? Do ultrapotassic compositions require continental subduction? Understanding chemically complex magmas emplaced in tectonically complex areas require open minds, and avoiding dogma and assumptions. Studying the geology and shallow dynamics, not speculating about the deep lower mantle, is the key to understanding the igneous activity.

  13. Design of Large Area PLEDs on Flexible Substrates: Highly Efficient Flexible Devices Using a Statistical Copolymer of Oxadiazole-Containing PPV

    DTIC Science & Technology

    2004-12-01

    Films and had a sheet resistance of 100 Ω per square. Multiple layer devices were made using PEDOT /PSS, poly(3,4-ethylenedioxythiophene) poly(styrene...polymer shows good performance. When PEDOT /PSS was coated on the ITO and LiF was evaporated between the emissive layer and Al, device efficiency is...the exciton decays back down to the ground state, hoton of light is emitted. To enhance device ormance, additional hole- and electron- cting

  14. Alpha-2 noradrenergic receptor activation inhibits the hyperpolarization-activated cation current (Ih ) in neurons of the ventral tegmental area

    PubMed Central

    Inyushin, Mikhail U.; Arencibia-Albite, Francisco; Vázquez-Torres, Rafael; Vélez-Hernández, María E.; Jiménez-Rivera, Carlos A.

    2010-01-01

    The ventral tegmental area (VTA) is the source of dopaminergic projections innervating cortical structures and ventral forebrain. Dysfunction of this mesocorticolimbic system is critically involved in psychiatric disorders such as addiction and schizophrenia. Changes in VTA dopamine (DA) neuronal activity can alter neurotransmitter release at target regions which modify information processing in the reward circuit. Here we studied the effect of α-2 noradrenergic receptor activation on the hyperpolarization-activated cation current (Ih ) in DA neurons of the rat VTA. Brain slice preparations using whole-cell current and voltage-clamp techniques were employed. Clonidine and UK14304 (α-2 receptor selective agonists) were found to decrease Ih amplitude and to slow its rate of activation indicating a negative shift in the current’s voltage dependence. Two non-subtype-selective α-2 receptor antagonists, yohimbine and RS79948, prevented the effects of α-2 receptor activation. RX821002, a noradrenergic antagonist specific for α-2A and α-2D did not prevent Ih inhibition. This result suggests that clonidine might be acting via an α-2C subtype since this receptor is the most abundant variant in the VTA. Analysis of a second messenger system associated with the α-2 receptor revealed that Ih inhibition is independent of cyclic adenosine monophosphate (cAMP) and resulted from the activation of protein kinase C. It is suggested that the α-2 mediated hyperpolarizing shift in Ih voltage dependence can facilitate the transition from pacemaker firing to afferent-driven burst activity. This transition may play a key role on the changes in synaptic plasticity that occurs in the mesocorticolimbic system under pathological conditions. PMID:20122999

  15. Cognitive conflict in a syllable identification task causes transient activation of speech perception area.

    PubMed

    Sætrevik, Bjørn; Specht, Karsten

    2012-04-01

    It has previously been shown that task performance and frontal cortical activation increase after cognitive conflict. This has been argued to support a model of attention where the level of conflict automatically adjusts the amount of cognitive control applied. Conceivably, conflict could also modulate lower-level processing pathways, which would be evident as trial-to-trial changes in domain specific activation. The present fMRI experiment used a syllable identification task where conflict is manipulated by presenting recently ignored syllables. Results showed that on trials following a high conflict trial, activation increased primarily in the planum temporale region of the left temporal cortex, an area believed to be involved in syllable discrimination. The experiment thus showed a transient, domain specific attention effect that was modulated on a trial-to-trial basis. We argue that this indicates a self-regulating system where increased levels of conflict directs resources in order to improve performance.

  16. Wireless device monitoring systems and monitoring devices, and associated methods

    DOEpatents

    McCown, Steven H; Derr, Kurt W; Rohde, Kenneth W

    2014-05-27

    Wireless device monitoring systems and monitoring devices include a communications module for receiving wireless communications of a wireless device. Processing circuitry is coupled with the communications module and configured to process the wireless communications to determine whether the wireless device is authorized or unauthorized to be present at the monitored area based on identification information of the wireless device. Methods of monitoring for the presence and identity of wireless devices are also provided.

  17. Support chemistry, surface area, and preparation effects on sulfided NiMo catalyst activity

    SciTech Connect

    Gardner, T.J.; McLaughlin, L.I.; Sandoval, R.S.

    1996-06-01

    Hydrous Metal Oxides (HMOs) are chemically synthesized materials which contain a homogeneous distribution of ion exchangeable alkali cations that provide charge compensation to the metal-oxygen framework. In terms of the major types of inorganic ion exchangers defined by Clearfield, these amorphous HMO materials are similar to both hydrous oxides and layered oxide ion exchangers (e.g., alkali metal titanates). For catalyst applications, the HMO material serves as an ion exchangeable support which facilitates the uniform incorporation of catalyst precursor species. Following catalyst precursor incorporation, an activation step is required to convert the catalyst precursor to the desired active phase. Considerable process development activities at Sandia National Laboratories related to HMO materials have resulted in bulk hydrous titanium oxide (HTO)- and silica-doped hydrous titanium oxide (HTO:Si)-supported NiMo catalysts that are more active in model reactions which simulate direct coal liquefaction (e.g., pyrene hydrogenation) than commercial {gamma}-Al{sub 2}O{sub 3}-supported NiMo catalysts. However, a fundamental explanation does not exist for the enhanced activity of these novel catalyst materials; possible reasons include fundamental differences in support chemistry relative to commercial oxides, high surface area, or catalyst preparation effects (ion exchange vs. incipient wetness impregnation techniques). The goals of this paper are to identify the key factors which control sulfided NiMo catalyst activity, including those characteristics of HTO- and HTO:Si-supported NiMo catalysts which uniquely set them apart from conventional oxide supports.

  18. Task-load-dependent activation of dopaminergic midbrain areas in the absence of reward.

    PubMed

    Boehler, Carsten N; Hopf, Jens-Max; Krebs, Ruth M; Stoppel, Christian M; Schoenfeld, Mircea A; Heinze, Hans-Jochen; Noesselt, Toemme

    2011-03-30

    Dopamine release in cortical and subcortical structures plays a central role in reward-related neural processes. Within this context, dopaminergic inputs are commonly assumed to play an activating role, facilitating behavioral and cognitive operations necessary to obtain a prospective reward. Here, we provide evidence from human fMRI that this activating role can also be mediated by task-demand-related processes and thus extends beyond situations that only entail extrinsic motivating factors. Using a visual discrimination task in which varying levels of task demands were precued, we found enhanced hemodynamic activity in the substantia nigra (SN) for high task demands in the absence of reward or similar extrinsic motivating factors. This observation thus indicates that the SN can also be activated in an endogenous fashion. In parallel to its role in reward-related processes, reward-independent activation likely serves to recruit the processing resources needed to meet enhanced task demands. Simultaneously, activity in a wide network of cortical and subcortical control regions was enhanced in response to high task demands, whereas areas of the default-mode network were deactivated more strongly. The present observations suggest that the SN represents a core node within a broader neural network that adjusts the amount of available neural and behavioral resources to changing situational opportunities and task requirements, which is often driven by extrinsic factors but can also be controlled endogenously.

  19. Morphine withdrawal enhances constitutive μ-opioid receptor activity in the ventral tegmental area.

    PubMed

    Meye, Frank J; van Zessen, Ruud; Smidt, Marten P; Adan, Roger A H; Ramakers, Geert M J

    2012-11-14

    μ-Opioid receptors (MORs) in the ventral tegmental area (VTA) are pivotally involved in addictive behavior. While MORs are typically activated by opioids, they can also become constitutively active in the absence of any agonist. In the current study, we present evidence that MOR constitutive activity is highly relevant in the mouse VTA, as it regulates GABAergic input to dopamine neurons. Specifically, suppression of MOR constitutive activity with the inverse agonist KC-2-009 enhanced GABAergic neurotransmission onto VTA dopamine neurons. This inverse agonistic effect was fully blocked by the specific MOR neutral antagonist CTOP, which had no effect on GABAergic transmission itself. We next show that withdrawal from chronic morphine further increases the magnitude of inverse agonistic effects at the MOR, suggesting enhanced MOR constitutive activity. We demonstrate that this increase can be an adaptive response to the detrimental elevation in cAMP levels known to occur during morphine withdrawal. These findings offer important insights in the physiological occurrence and function of MOR constitutive activity, and have important implications for therapeutic strategies aimed at normalizing MOR signaling during addiction and opioid overdose.

  20. Physical Activity, Sedentary Behavior and Substance Use among Adolescents in Slovenian Urban Area

    PubMed Central

    LESJAK, Vesna; STANOJEVIĆ-JERKOVIĆ, Olivera

    2015-01-01

    Background Studies of the relationship between leisure time physical activity, sedentary behaviour and substance use among adolescents report contradictory results. The aim of our study was to examine the association between self-reported leisure time physical activity, sedentary behaviour and alcohol, tobacco and cannabis use among adolescents in Slovenia. Methods Subjects consisted of 822 school children aged from 14 to 16 years, living in urban area of Ljubljana and Maribor. The data was collected using the EURO URHIS 2 survey. Logistic regressions were conducted to assess the correlation between the independent variables of physical activity; time spent watching television and using the computer, and each of the five substance use dependent variables. Results Frequency of daily smoking was significantly associated with leisure time physical activity, while alcohol and cannabis use were not. Watching TV ≥ 2 hours per day was associated with heavy episodic drinking in the past month, no associations were found for smoking and cannabis use. Using the computer ≥ 2 hours per day was positively associated with daily smoking, drinking alcohol in the past month, heavy episodic drinking in the past month and ever being intoxicated, while cannabis use was not. Conclusions These findings suggest that leisure time physical activity is associated with daily cigarette smoking, and leisure time sedentary behaviour is associated with alcohol and tobacco use among adolescents. The results of our study show the need for the formation of suitable preventive measures concerning reduced sitting time as well as leisure time physical activity targeted to adolescents. PMID:27646724